1 00:00:01,591 --> 00:00:02,700 (gasps) Daddy! 2 00:00:02,700 --> 00:00:04,290 We love you. You're going to beat this. 3 00:00:04,290 --> 00:00:06,080 We need you. 4 00:00:06,080 --> 00:00:09,130 Over 21 million people infected. 5 00:00:09,130 --> 00:00:12,110 We lost three people within an hour. 6 00:00:12,110 --> 00:00:14,653 {\an8}You don't get time to like pause. 7 00:00:16,219 --> 00:00:19,283 700,000 have lost their lives. 8 00:00:20,610 --> 00:00:23,730 As the pandemic, tightens its grip on the world, 9 00:00:23,730 --> 00:00:25,880 there are important unanswered questions 10 00:00:25,880 --> 00:00:27,793 about the novel coronavirus. 11 00:00:28,760 --> 00:00:31,680 Why does this infection spread so rapidly 12 00:00:31,680 --> 00:00:33,533 from people with no symptoms? 13 00:00:34,830 --> 00:00:38,323 Why do some people become critical while others don't? 14 00:00:40,670 --> 00:00:42,873 {\an8}Will a definitive treatment be found? 15 00:00:45,080 --> 00:00:47,640 {\an8}The underlying key to these questions 16 00:00:47,640 --> 00:00:50,563 {\an8}lie in our immune system. 17 00:00:53,470 --> 00:00:56,710 Immune cells are microscopic warriors, 18 00:00:56,710 --> 00:01:00,150 combating viruses, which invade our bodies. 19 00:01:00,150 --> 00:01:02,693 {\an8}And we have two trillion of them. 20 00:01:07,780 --> 00:01:11,920 Immune cells rapidly detect and devour the enemy, 21 00:01:11,920 --> 00:01:14,620 {\an8}inject toxins to destroy them 22 00:01:14,620 --> 00:01:18,263 {\an8}and even release a sticky web to ensnare them. 23 00:01:23,780 --> 00:01:27,810 {\an8}The latest scientific discoveries are starting to shed light 24 00:01:27,810 --> 00:01:30,943 {\an8}on the enigmatic mechanism behind immunity. 25 00:01:34,290 --> 00:01:36,710 As for the novel coronavirus, 26 00:01:36,710 --> 00:01:40,400 it's become clear that it can break down our immune defenses 27 00:01:40,400 --> 00:01:42,283 with its formidable powers. 28 00:01:45,240 --> 00:01:50,240 It slips through, suppresses and unleashes chaos. 29 00:01:57,800 --> 00:02:00,900 {\an8}In this program, state-of-the-art microscopy 30 00:02:00,900 --> 00:02:04,920 {\an8}and extensive CGI will reveal a battleground, 31 00:02:04,920 --> 00:02:09,870 never seen before: the war between the novel coronavirus 32 00:02:09,870 --> 00:02:11,513 and our immune system. 33 00:02:14,290 --> 00:02:18,230 Research taking place around the world about our immunity 34 00:02:18,230 --> 00:02:20,840 is helping to find potential new treatments 35 00:02:20,840 --> 00:02:22,633 to combat the coronavirus. 36 00:02:24,360 --> 00:02:27,003 Vaccines are being rapidly developed, 37 00:02:28,870 --> 00:02:32,370 {\an8}and it's been found that even blood from recovered patients 38 00:02:32,370 --> 00:02:34,100 {\an8}can be used to save the lives 39 00:02:34,100 --> 00:02:36,723 {\an8}of patients suffering from severe symptoms. 40 00:02:39,400 --> 00:02:41,363 Aided by cutting edge science, 41 00:02:42,630 --> 00:02:45,210 we'll unveil the astonishing powers 42 00:02:45,210 --> 00:02:47,173 of this novel coronavirus, 43 00:02:50,360 --> 00:02:53,520 as well as the ways in which we may be able to overcome 44 00:02:53,520 --> 00:02:55,529 this formidable enemy. 45 00:02:55,529 --> 00:02:58,862 (dramatic dreamy music) 46 00:03:10,370 --> 00:03:15,133 Cases of COVID-19 continue to surge around the world. 47 00:03:18,710 --> 00:03:21,380 The virus spreads from tiny droplets 48 00:03:21,380 --> 00:03:24,213 that are released from an infected person's mouth. 49 00:03:30,800 --> 00:03:34,350 {\an8}A special camera system has been used to film droplets 50 00:03:34,350 --> 00:03:37,163 {\an8}that are exhaled from our mouths as we talk. 51 00:03:38,480 --> 00:03:40,280 {\an8}They are tiny, 52 00:03:40,280 --> 00:03:43,823 {\an8}smaller than a thousandth of a millimeter in diameter. 53 00:03:46,890 --> 00:03:51,590 {\an8}A droplet around one millimeter across can in fact contain 54 00:03:51,590 --> 00:03:54,690 {\an8}as much as seven million virus particles 55 00:03:59,550 --> 00:04:03,503 {\an8}So if you get infected, what happens to your body? 56 00:04:06,900 --> 00:04:11,540 Advanced microscopic technologies are powerful tools 57 00:04:11,540 --> 00:04:14,753 that help us visualize this world within. 58 00:04:16,950 --> 00:04:20,800 For instance, this next generation microscope 59 00:04:20,800 --> 00:04:24,293 {\an8}enables us to observe living cells at work. 60 00:04:25,230 --> 00:04:29,113 {\an8}It captures our immune cells in attack mode in 3D. 61 00:04:33,830 --> 00:04:38,830 {\an8}Other tools such as ultra high resolution 8K microscopy, 62 00:04:39,790 --> 00:04:43,533 {\an8}3D reconstructions of electron microscope images, 63 00:04:44,640 --> 00:04:47,990 {\an8}as well as the latest CGI techniques 64 00:04:47,990 --> 00:04:52,130 {\an8}will allow us to see the battles between viruses 65 00:04:52,130 --> 00:04:53,883 {\an8}and our body's cells. 66 00:04:57,740 --> 00:05:00,680 Now let's dive in to take a look 67 00:05:00,680 --> 00:05:03,933 at this microscopic universe within our body. 68 00:05:05,680 --> 00:05:07,659 Carried by these droplets, the novel coronavirus 69 00:05:07,659 --> 00:05:11,523 gets into our body through the mouth. 70 00:05:13,880 --> 00:05:16,280 But it can't just keep going. 71 00:05:16,280 --> 00:05:19,830 The first barrier it meets is our respiratory tract, 72 00:05:19,830 --> 00:05:21,803 the airway that leads to the lungs. 73 00:05:24,120 --> 00:05:26,300 This image of the respiratory tract 74 00:05:26,300 --> 00:05:29,050 {\an8}magnified by more than 10,000 times 75 00:05:29,050 --> 00:05:32,990 {\an8}by an electron microscope shows many hairlike structures 76 00:05:32,990 --> 00:05:35,863 {\an8}growing on the surface called cilia. 77 00:05:37,400 --> 00:05:40,930 They are about a hundredth of a strand of human hair 78 00:05:40,930 --> 00:05:43,290 and make tiny rapid movements 79 00:05:43,290 --> 00:05:45,403 over a thousand times per minute. 80 00:05:47,020 --> 00:05:49,990 These movements allow foreign matters such as viruses 81 00:05:49,990 --> 00:05:51,243 to be pushed away. 82 00:05:52,910 --> 00:05:55,390 However, the novel coronavirus 83 00:05:55,390 --> 00:05:58,950 can also infect these celia cells. 84 00:05:58,950 --> 00:06:01,400 By stopping their sweeping movements, 85 00:06:01,400 --> 00:06:02,983 it definitely slips through. 86 00:06:04,170 --> 00:06:06,540 It then passes through the airways 87 00:06:06,540 --> 00:06:10,193 and finally works its way deep into the lungs. 88 00:06:11,510 --> 00:06:13,953 The infection is about to begin. 89 00:06:17,640 --> 00:06:20,210 The virus particle approaches a lung cell 90 00:06:22,580 --> 00:06:25,360 It's target is a strange looking protrusion 91 00:06:25,360 --> 00:06:26,760 on the cell surface 92 00:06:26,760 --> 00:06:29,993 measuring only 100,000th of a millimeter. 93 00:06:35,410 --> 00:06:38,360 The novel coronavirus attaches its spike 94 00:06:38,360 --> 00:06:41,063 onto this protrusion on the cell surface. 95 00:06:42,090 --> 00:06:46,243 Then the virus slowly burrows into the cell. 96 00:06:48,470 --> 00:06:50,893 The infection is now complete. 97 00:06:53,942 --> 00:06:58,053 This is a cunning trick, unique to viruses. 98 00:07:00,350 --> 00:07:02,640 The protrusions on the cell surface 99 00:07:02,640 --> 00:07:04,450 normally act like a keyhole 100 00:07:06,270 --> 00:07:09,853 only letting in essential substances, such as cholesterol. 101 00:07:12,260 --> 00:07:15,823 Only those who have the right key can enter the cell. 102 00:07:16,823 --> 00:07:19,323 (tense music) 103 00:07:26,370 --> 00:07:30,250 But the novel coronavirus has a fake key 104 00:07:30,250 --> 00:07:33,640 that fits perfectly with the cell's keyhole. 105 00:07:33,640 --> 00:07:35,430 It basically tricks the cell 106 00:07:35,430 --> 00:07:37,873 into letting an intruder inside. 107 00:07:42,020 --> 00:07:45,060 {\an8}Image taken by an electron microscope 108 00:07:45,060 --> 00:07:47,000 {\an8}shows the inside of a cell 109 00:07:47,000 --> 00:07:50,490 {\an8}that's been infected by the novel coronavirus. 110 00:07:50,490 --> 00:07:53,710 {\an8}The red dots are all virus particles 111 00:07:56,240 --> 00:08:00,210 {\an8}Once inside a cell, the virus can replicate itself 112 00:08:00,210 --> 00:08:03,683 {\an8}as much as a thousand times before breaking out. 113 00:08:06,930 --> 00:08:08,680 {\an8}This is a microscopic image 114 00:08:08,680 --> 00:08:10,970 {\an8}taken by the U.S. National Institute 115 00:08:10,970 --> 00:08:13,483 {\an8}of Allergy and Infectious Diseases. 116 00:08:14,850 --> 00:08:19,850 {\an8}It captures the moment where coronavirus particles in red 117 00:08:19,880 --> 00:08:22,563 {\an8}have burst out of an infected cell. 118 00:08:27,080 --> 00:08:31,060 Vast amounts of viral particles scatter all around, 119 00:08:31,060 --> 00:08:33,723 looking for new cells to infect. 120 00:08:35,370 --> 00:08:37,253 {\an8}let's see what happens next. 121 00:08:39,350 --> 00:08:43,280 {\an8}This is an X-ray image of a COVID-19 patient, 122 00:08:43,280 --> 00:08:45,303 {\an8}and the lungs are shown in black. 123 00:08:47,160 --> 00:08:50,450 {\an8}These wWhite spots indicate areas of inflammation 124 00:08:50,450 --> 00:08:53,110 {\an8}caused by the viral infection. 125 00:08:53,110 --> 00:08:56,603 {\an8}As these spread, symptoms of pneumonia worsen. 126 00:09:00,030 --> 00:09:04,670 {\an8}Our immune cells, the defense corps that protect our bodies 127 00:09:04,670 --> 00:09:07,593 {\an8}are mobilized to prevent such a crisis. 128 00:09:09,720 --> 00:09:12,460 A cell infected with a novel coronavirus 129 00:09:12,460 --> 00:09:15,853 starts to release large amounts of blue particles. 130 00:09:17,640 --> 00:09:21,710 This substance called interferon is an alarm 131 00:09:21,710 --> 00:09:24,513 that warns immune cells of danger. 132 00:09:29,940 --> 00:09:33,683 {\an8}It is a message alerting them to the presence of an enemy. 133 00:09:34,810 --> 00:09:37,700 The alert is carried all across the body 134 00:09:37,700 --> 00:09:39,670 {\an8}through the bloodstream. 135 00:09:39,670 --> 00:09:43,260 {\an8}Messages are received by round cells like these 136 00:09:43,260 --> 00:09:45,163 {\an8}roaming in our blood vessels. 137 00:09:46,140 --> 00:09:48,913 {\an8}These immune cells are called phagocytes. 138 00:09:52,060 --> 00:09:55,573 {\an8}This is a video of an inside of a blood vessel. 139 00:09:56,570 --> 00:10:00,890 {\an8}Normally phagocytes are on patrol inside these blood vessels 140 00:10:00,890 --> 00:10:02,453 {\an8}all around our bodies. 141 00:10:03,540 --> 00:10:05,170 And when they receive a message, 142 00:10:05,170 --> 00:10:07,990 alerting them of an enemy incursion, 143 00:10:07,990 --> 00:10:09,930 {\an8}they head out from the blood vessel 144 00:10:09,930 --> 00:10:11,313 {\an8}to the site of infection. 145 00:10:13,060 --> 00:10:15,880 {\an8}When phagocytes locate their target, 146 00:10:15,880 --> 00:10:18,190 {\an8}foreign matter, such as viruses, 147 00:10:18,190 --> 00:10:21,010 {\an8}they move in and devour it whole 148 00:10:23,120 --> 00:10:26,673 even if their targets are larger than themselves. 149 00:10:36,080 --> 00:10:39,270 People who are infected with the novel coronavirus, 150 00:10:39,270 --> 00:10:41,410 but remain asymptomatic, 151 00:10:41,410 --> 00:10:44,963 are thought to have very active phagocytes in their bodies. 152 00:10:46,690 --> 00:10:50,350 These powerful defense units, which engulf their enemy 153 00:10:50,350 --> 00:10:52,933 are known as our innate immunity. 154 00:10:53,820 --> 00:10:57,103 A part of our immune system that's been with us since birth. 155 00:11:04,960 --> 00:11:08,100 {\an8}But why do symptoms keep getting worse in some people, 156 00:11:08,100 --> 00:11:11,093 {\an8}even though they are protected by innate immunity? 157 00:11:13,160 --> 00:11:16,763 The latest research has uncovered an intriguing possibility. 158 00:11:18,400 --> 00:11:22,040 The novel coronavirus may be evading such attacks 159 00:11:22,040 --> 00:11:24,003 from our innate immune system. 160 00:11:25,840 --> 00:11:28,970 {\an8}This was discovered by dr. Kei Sato 161 00:11:28,970 --> 00:11:32,163 {\an8}at the Tokyo university Medical Research Institute. 162 00:11:34,710 --> 00:11:37,790 Dr. Sato looked at the genetic information 163 00:11:37,790 --> 00:11:40,713 stored inside the novel coronavirus. 164 00:11:45,460 --> 00:11:48,670 {\an8}When he compared these with other types of viruses, 165 00:11:48,670 --> 00:11:52,653 {\an8}he discovered that the novel coronavirus had a unique gene. 166 00:11:54,390 --> 00:11:57,250 He conducted experiments to find out the function 167 00:11:57,250 --> 00:11:58,703 of this particular gene. 168 00:12:00,060 --> 00:12:03,020 And it became clear that it gave the virus 169 00:12:03,020 --> 00:12:06,753 the ability to deceive our innate immunity. 170 00:12:09,710 --> 00:12:13,520 Remember, a cell infected with the virus 171 00:12:13,520 --> 00:12:16,350 releases masses of alert messages 172 00:12:16,350 --> 00:12:19,063 to warn others of the presence of an enemy. 173 00:12:23,100 --> 00:12:26,200 But when this special gene in the novel coronavirus 174 00:12:26,200 --> 00:12:30,870 is activated, these alerts are suppressed. 175 00:12:30,870 --> 00:12:34,243 So only about a 10th of these warnings get out. 176 00:12:41,610 --> 00:12:45,510 If this happens, alerts of an enemy invasion 177 00:12:45,510 --> 00:12:48,420 failed to get through to the phagocytes, 178 00:12:48,420 --> 00:12:51,090 so they can't be mobilized. 179 00:12:51,090 --> 00:12:55,873 The virus is left at large, free to replicate at will. 180 00:12:58,010 --> 00:12:59,560 {\an8}Another study has found 181 00:12:59,560 --> 00:13:02,870 {\an8}that in the absence of these warning substances, 182 00:13:02,870 --> 00:13:05,050 {\an8}the novel coronavirus can replicate 183 00:13:05,050 --> 00:13:09,603 {\an8}by as many as 10,000 times in just two days. 184 00:13:12,510 --> 00:13:13,343 Research has shown 185 00:13:13,343 --> 00:13:14,870 that people with severe symptoms 186 00:13:14,870 --> 00:13:17,203 produce lower levels of interferons. 187 00:13:18,320 --> 00:13:20,840 It's very likely that this is allowing viruses 188 00:13:20,840 --> 00:13:24,963 to spread throughout the body, resulting in severe symptoms. 189 00:13:29,520 --> 00:13:32,250 {\an8}Suppressing the human body's red alerts 190 00:13:32,250 --> 00:13:34,763 is one weapon in the viruses arsenal. 191 00:13:36,690 --> 00:13:39,810 {\an8}This may also be the reason why COVID-19 192 00:13:39,810 --> 00:13:42,433 {\an8}has become such a global emergency. 193 00:13:47,280 --> 00:13:48,890 Countries around the world 194 00:13:48,890 --> 00:13:50,800 have been taking desperate measures, 195 00:13:50,800 --> 00:13:53,880 such as lockdowns at the cost of their economy 196 00:13:53,880 --> 00:13:56,343 in a bid to halt the spread of infection. 197 00:13:58,730 --> 00:14:01,720 But the difficulty is that in many cases, 198 00:14:01,720 --> 00:14:04,853 there is a delay before any symptoms appear. 199 00:14:06,210 --> 00:14:09,530 So if people are unaware that they'd been infected, 200 00:14:09,530 --> 00:14:11,673 they can go on to infect others. 201 00:14:15,470 --> 00:14:18,750 Usually when we are infected by a virus, 202 00:14:18,750 --> 00:14:21,563 an alert substance is released in our bodies. 203 00:14:22,910 --> 00:14:25,290 This causes our body temperature to rise 204 00:14:25,290 --> 00:14:28,033 in order to activate the immune response. 205 00:14:29,180 --> 00:14:31,650 However, since the novel coronavirus 206 00:14:31,650 --> 00:14:34,280 is suppressing these warning signals, 207 00:14:34,280 --> 00:14:36,120 there are still no fever, 208 00:14:36,120 --> 00:14:38,983 even though the viral load keeps increasing. 209 00:14:42,370 --> 00:14:46,510 So due to this superficially asymptomatic state, 210 00:14:46,510 --> 00:14:49,630 people may not realize that they're infected 211 00:14:49,630 --> 00:14:53,063 and this could be how the virus is going unchecked. 212 00:14:58,400 --> 00:15:01,983 New studies have shown something even more disturbing. 213 00:15:03,680 --> 00:15:08,060 The virus's ability to suppress these warning signals 214 00:15:08,060 --> 00:15:10,003 may be getting stronger. 215 00:15:14,440 --> 00:15:17,560 {\an8}This diagram shows the different genetic types 216 00:15:17,560 --> 00:15:19,300 {\an8}of the novel coronavirus 217 00:15:19,300 --> 00:15:21,600 {\an8}that have been spreading throughout the world. 218 00:15:23,370 --> 00:15:28,343 {\an8}You can see how new types appear as each branch splits away. 219 00:15:33,340 --> 00:15:36,103 Let's look at this strain found in Ecuador. 220 00:15:37,870 --> 00:15:40,390 There is a slight alteration in the gene 221 00:15:40,390 --> 00:15:42,373 that suppresses the alarm substance. 222 00:15:47,110 --> 00:15:50,923 In Ecuador the virus has been spreading rapidly since April. 223 00:15:59,540 --> 00:16:03,110 {\an8}Dr. Paul Cardenas has been studying COVID-19 patients 224 00:16:03,110 --> 00:16:05,423 at a hospital in the capital of Quito. 225 00:16:08,067 --> 00:16:10,200 The two patients are brothers. 226 00:16:10,200 --> 00:16:15,040 They are young, all of them and develop the symptoms 227 00:16:15,040 --> 00:16:16,550 almost at the same time. 228 00:16:16,550 --> 00:16:19,490 And the whole family went to the intensive care unit. 229 00:16:19,490 --> 00:16:21,662 In terms of infectious diseases 230 00:16:21,662 --> 00:16:25,600 in our respiratory infection, it's very rare. 231 00:16:25,600 --> 00:16:27,660 I mean, usually you have young people 232 00:16:27,660 --> 00:16:30,273 developing those symptoms that week. 233 00:16:31,380 --> 00:16:33,210 After collecting virus samples 234 00:16:33,210 --> 00:16:35,920 from the brothers and analyzing their genes, 235 00:16:35,920 --> 00:16:38,783 a mutation was found in that special gene. 236 00:16:41,690 --> 00:16:44,950 Experiments confirmed that because of this change, 237 00:16:44,950 --> 00:16:47,250 {\an8}the quantity of alarm substances made 238 00:16:47,250 --> 00:16:51,003 {\an8}was being reduced even further - to one 20th. 239 00:16:53,340 --> 00:16:55,930 If this powerful strain spreads, 240 00:16:55,930 --> 00:16:58,600 our immune systems defense corps will be forced 241 00:16:58,600 --> 00:17:01,923 to fight even tougher battles against the coronavirus. 242 00:17:05,890 --> 00:17:09,133 {\an8}There are many other variants of the novel coronavirus, 243 00:17:09,133 --> 00:17:12,693 {\an8}a new types keep emerging due to genetic changes. 244 00:17:14,570 --> 00:17:17,470 {\an8}Such changes may create further variants 245 00:17:17,470 --> 00:17:20,750 {\an8}that could even be resistant to vaccines or drugs 246 00:17:20,750 --> 00:17:22,987 {\an8}that are currently being developed. 247 00:17:29,170 --> 00:17:33,370 If the novel coronavirus manages to successfully evade 248 00:17:33,370 --> 00:17:37,820 our innate immune system and continues to multiply, 249 00:17:37,820 --> 00:17:40,853 {\an8}let's see what happens next in our bodies. 250 00:17:44,620 --> 00:17:48,010 {\an8}In most cases, patients remain asymptomatic 251 00:17:48,010 --> 00:17:51,030 for around five after infection, 252 00:17:51,030 --> 00:17:55,000 but when the viral load in the body exceeds a certain limit, 253 00:17:55,000 --> 00:17:56,680 they begin to develop symptoms 254 00:17:56,680 --> 00:17:59,643 {\an8}such as fever, cough, and fatigue. 255 00:18:01,266 --> 00:18:03,849 {\an8}(man coughing) 256 00:18:05,700 --> 00:18:10,240 Having overrun our innate immunity, the novel coronavirus 257 00:18:10,240 --> 00:18:12,287 is now replicating itself (indistinct). 258 00:18:14,310 --> 00:18:18,163 However, our immune system hasn't given up yet. 259 00:18:19,020 --> 00:18:21,780 This is when our secondary defense force, 260 00:18:21,780 --> 00:18:25,133 our adaptive immune system, is deployed. 261 00:18:29,640 --> 00:18:32,580 One of the phagocytes that had been fighting the virus 262 00:18:32,580 --> 00:18:35,630 is moving off to a different location. 263 00:18:35,630 --> 00:18:39,693 It's now acting as a messenger, seeking reinforcements. 264 00:18:44,360 --> 00:18:48,313 The messenger attaches itself to a blue immune cell. 265 00:18:51,100 --> 00:18:52,503 Let's look closer. 266 00:18:56,260 --> 00:18:58,980 The messenger cell is holding out a fragment 267 00:18:58,980 --> 00:19:02,760 of the novel coronavirus it had devoured earlier 268 00:19:02,760 --> 00:19:04,783 on something that looks like clasp. 269 00:19:08,030 --> 00:19:12,263 The blue immune cell accepts it. This is enemy intel. 270 00:19:14,590 --> 00:19:17,063 The immune cell is now activated. 271 00:19:26,130 --> 00:19:29,793 This is a killer T cell ready to attack. 272 00:19:30,910 --> 00:19:34,280 These killer T cells specifically target cells, 273 00:19:34,280 --> 00:19:37,193 which are infected with the novel coronavirus. 274 00:19:46,580 --> 00:19:49,360 Fragments of the virus can be seen protruding 275 00:19:49,360 --> 00:19:51,883 from the surfaces of infected cells. 276 00:19:54,100 --> 00:19:57,010 Killer T cells compare these fragments 277 00:19:57,010 --> 00:20:00,090 with the intel they'd received earlier. 278 00:20:00,090 --> 00:20:03,310 If they match and their target is confirmed, 279 00:20:03,310 --> 00:20:05,093 they commence their attack. 280 00:20:06,170 --> 00:20:10,413 The virus, as well as the cell are completely obliterated. 281 00:20:18,300 --> 00:20:21,570 {\an8}A cutting edge microscope has caught this moment of attack 282 00:20:21,570 --> 00:20:23,023 {\an8}by a killer T cell. 283 00:20:24,030 --> 00:20:26,253 {\an8}In green is the killer T cell. 284 00:20:27,570 --> 00:20:32,000 {\an8}Once it attaches itself to its target cell in blue, 285 00:20:32,000 --> 00:20:35,453 it injects a toxic substance shown in red. 286 00:20:38,110 --> 00:20:43,013 It destroys the infected cell along with the viruses inside. 287 00:20:49,920 --> 00:20:54,150 {\an8}However, it now appears that the novel coronavirus 288 00:20:54,150 --> 00:20:58,223 {\an8}may even be able to dodge a killer T cell attack. 289 00:21:02,100 --> 00:21:03,770 Recent findings from China 290 00:21:03,770 --> 00:21:06,100 suggest that the novel coronavirus 291 00:21:06,100 --> 00:21:10,223 has a unique quality setting it apart from other viruses. 292 00:21:12,960 --> 00:21:17,400 It seems to target those clasps on an infected cell, 293 00:21:17,400 --> 00:21:19,323 which hold out viral fragments. 294 00:21:21,760 --> 00:21:24,210 Their research has suggested that the virus 295 00:21:24,210 --> 00:21:26,820 {\an8}is breaking down these clasps 296 00:21:26,820 --> 00:21:30,310 {\an8}even before they can reach out of the cell surface, 297 00:21:30,310 --> 00:21:33,713 {\an8}reducing their numbers by 60%. 298 00:21:35,740 --> 00:21:38,850 This makes it much harder for the killer T cells 299 00:21:38,850 --> 00:21:41,123 to locate infected cells. 300 00:21:44,520 --> 00:21:47,360 The infection remains unchecked, 301 00:21:47,360 --> 00:21:49,893 and the virus continues to multiply. 302 00:21:52,560 --> 00:21:57,340 In retaliation, our immune system sends out another unit: 303 00:21:57,340 --> 00:21:58,523 the B cells. 304 00:22:02,620 --> 00:22:05,200 B cells also get their enemy intel 305 00:22:05,200 --> 00:22:07,880 through the contact with viral fragments 306 00:22:07,880 --> 00:22:11,033 and they produce powerful projectile weapons. 307 00:22:14,800 --> 00:22:17,070 See how the B cell starts to release 308 00:22:17,070 --> 00:22:19,680 those small yellow particles? 309 00:22:19,680 --> 00:22:22,633 These projectiles are called antibodies. 310 00:22:25,760 --> 00:22:28,030 When magnified under a microscope, 311 00:22:28,030 --> 00:22:29,763 it looks like the letter Y. 312 00:22:30,990 --> 00:22:32,223 How do they work? 313 00:22:38,220 --> 00:22:40,590 Antibodies released from B cells 314 00:22:40,590 --> 00:22:43,263 close in on the novel coronavirus. 315 00:22:48,530 --> 00:22:53,300 They bind to those spikes, the fake keys that viruses use 316 00:22:53,300 --> 00:22:55,083 to invade human cells. 317 00:22:59,830 --> 00:23:02,690 Once the cell is covered with antibodies, 318 00:23:02,690 --> 00:23:05,943 the virus can no longer infect or replicate. 319 00:23:08,480 --> 00:23:10,070 With nowhere to go, 320 00:23:10,070 --> 00:23:13,653 they are devoured one by one by phagocytes. 321 00:23:20,520 --> 00:23:24,450 {\an8}Once you've reached this stage, you're out of the woods. 322 00:23:24,450 --> 00:23:27,113 {\an8}Your body will start recovering slowly. 323 00:23:30,370 --> 00:23:35,350 But the work of T cells and B cells doesn't end here: 324 00:23:35,350 --> 00:23:38,070 they retain their memories about the virus 325 00:23:38,070 --> 00:23:41,333 and continue to stay alert in our bodies. 326 00:23:42,990 --> 00:23:45,950 So if there is another coronavirus invasion, 327 00:23:45,950 --> 00:23:48,093 they will be ready to fight back. 328 00:23:55,400 --> 00:23:58,620 These special units study the enemy, 329 00:23:58,620 --> 00:24:02,980 launch an intensive attack, and even after repelling them, 330 00:24:02,980 --> 00:24:06,523 they remain vigilant to protect our bodies from harm. 331 00:24:08,620 --> 00:24:11,963 It's our adaptive immune system in action. 332 00:24:19,190 --> 00:24:22,660 Vaccines being developed against COVID-19 333 00:24:22,660 --> 00:24:24,840 are attempting to enhance the power 334 00:24:24,840 --> 00:24:26,973 of this adaptive immune system. 335 00:24:28,840 --> 00:24:31,050 Fragments from an attenuated virus 336 00:24:31,050 --> 00:24:33,240 are injected into the body. 337 00:24:33,240 --> 00:24:35,840 So that information on the novel coronavirus 338 00:24:35,840 --> 00:24:40,143 can be passed on safely to T cells and B cells. 339 00:24:42,960 --> 00:24:46,000 In this way, the adaptive immune system 340 00:24:46,000 --> 00:24:49,900 can learn about the enemy before any infection occurs 341 00:24:49,900 --> 00:24:51,863 and be prepared to attack. 342 00:24:54,370 --> 00:24:57,410 Researchers are working as quickly as they can 343 00:24:57,410 --> 00:25:00,070 to ensure the safety of these vaccines 344 00:25:00,070 --> 00:25:02,653 and maximize their effectiveness. 345 00:25:05,500 --> 00:25:10,500 While vaccine trials continue, the virus spreads worldwide. 346 00:25:11,150 --> 00:25:14,490 It has infected more than 21 million people 347 00:25:14,490 --> 00:25:18,043 and taken the lives of over 760,000. 348 00:25:20,400 --> 00:25:23,080 So what may have happened in the bodies of patients 349 00:25:23,080 --> 00:25:26,823 who became critical and ultimately lost their lives? 350 00:25:30,380 --> 00:25:34,390 The University Medical Center Hamburg-Eppendorf in Germany 351 00:25:34,390 --> 00:25:38,226 {\an8}has conducted more than 150 autopsies. 352 00:25:38,226 --> 00:25:40,809 {\an8}(somber music) 353 00:25:46,070 --> 00:25:49,560 {\an8}Scientists here discovered something unusual 354 00:25:49,560 --> 00:25:52,253 {\an8}in the lungs of COVID-19 patients. 355 00:25:56,340 --> 00:25:59,260 {\an8}From our past studies, where we learned 356 00:25:59,260 --> 00:26:03,550 {\an8}that with every new disease, there are new findings. 357 00:26:03,550 --> 00:26:06,373 {\an8}When you do autopsy on a regular basis, 358 00:26:08,100 --> 00:26:11,310 {\an8}we thought it might be very interesting 359 00:26:11,310 --> 00:26:14,310 from a scientific point of view, 360 00:26:14,310 --> 00:26:18,480 to get it more into detail in COVID-19. 361 00:26:18,480 --> 00:26:21,140 We were really, really surprised 362 00:26:21,140 --> 00:26:23,950 about the very, very high incidents 363 00:26:23,950 --> 00:26:28,110 of venous thromboembolisms and pulmonary embolisms. 364 00:26:28,110 --> 00:26:32,108 We discovered that within the first 12 patients, 365 00:26:32,108 --> 00:26:35,490 we had about one third of patients 366 00:26:35,490 --> 00:26:38,233 who died from pulmonary embolism. 367 00:26:39,720 --> 00:26:42,030 {\an8}Pulmonary embolism is a disease 368 00:26:42,030 --> 00:26:44,743 {\an8}where blood clots form in the lungs. 369 00:26:50,950 --> 00:26:53,840 {\an8}This is a blood clot that was found in the lung 370 00:26:53,840 --> 00:26:56,160 {\an8}of a COVID-19 patient. 371 00:26:56,160 --> 00:26:59,030 It caused their blood circulation to fail. 372 00:26:59,030 --> 00:27:02,193 And the resulting lack of oxygen led to their death. 373 00:27:04,240 --> 00:27:06,533 What could have caused these blood clots? 374 00:27:09,930 --> 00:27:12,850 {\an8}A closer look shows many of these blue dots 375 00:27:12,850 --> 00:27:14,993 {\an8}amongst the red clots of blood. 376 00:27:15,900 --> 00:27:19,000 {\an8}They are the dead remains of a type of phagocyte 377 00:27:19,000 --> 00:27:22,503 {\an8}called neutrophils, that had caused the clots. 378 00:27:28,970 --> 00:27:31,440 Clotting is triggered when our immune system 379 00:27:31,440 --> 00:27:36,143 goes into overdrive, a phenomenon called a cytokine storm. 380 00:27:39,830 --> 00:27:42,810 When viruses replicate in huge numbers, 381 00:27:42,810 --> 00:27:46,043 our immune cells can become overly activated. 382 00:27:47,790 --> 00:27:51,960 Researchers had long suspected that hyperactive immune cells 383 00:27:51,960 --> 00:27:54,923 {\an8}were inadvertently damaging our blood vessels. 384 00:27:56,100 --> 00:27:58,320 {\an8}And in order to close the wound, 385 00:27:58,320 --> 00:28:00,740 {\an8}platelets in the blood would come together 386 00:28:02,260 --> 00:28:05,441 {\an8}to form blood clots, becoming bigger 387 00:28:05,441 --> 00:28:08,683 and ultimately blocking circulation. 388 00:28:14,530 --> 00:28:17,140 {\an8}But here's the important point: 389 00:28:17,140 --> 00:28:18,980 {\an8}Recent research has shed light 390 00:28:18,980 --> 00:28:21,540 {\an8}on an even more disturbing mechanism 391 00:28:21,540 --> 00:28:25,603 {\an8}where a cytokine storm can trigger blood clot formation. 392 00:28:28,410 --> 00:28:31,660 {\an8}When neutrophils start to detect 393 00:28:31,660 --> 00:28:33,230 {\an8}that there are these pathogens 394 00:28:33,230 --> 00:28:34,860 {\an8}circulating in the bloodstream, 395 00:28:34,860 --> 00:28:39,090 {\an8}they will start to take their DNA inside of the cell 396 00:28:39,090 --> 00:28:41,930 {\an8}and they expel it outside the cell. 397 00:28:41,930 --> 00:28:43,880 {\an8}They spit it out to form something 398 00:28:43,880 --> 00:28:46,650 {\an8}called a neutrophil extracellular trap. 399 00:28:46,650 --> 00:28:48,980 {\an8}We know that certain cytokines that are released 400 00:28:48,980 --> 00:28:52,597 {\an8}in the setting of COVID-19 can prime the neutrophil 401 00:28:52,597 --> 00:28:56,200 {\an8}and make the neutrophil more likely to form NETs. 402 00:28:56,200 --> 00:29:01,160 {\an8}Neutrophil extracellular traps called NETs 403 00:29:01,160 --> 00:29:03,800 {\an8}is essentially a suicide attack. 404 00:29:03,800 --> 00:29:06,643 {\an8}And it was first discovered in 2004. 405 00:29:07,870 --> 00:29:12,230 This image captured by the Max Planck Institute in Germany 406 00:29:12,230 --> 00:29:14,283 shows the moment of attack. 407 00:29:15,410 --> 00:29:19,690 The yellow phagocyte is a 100th of a millimeter wide, 408 00:29:19,690 --> 00:29:22,870 it's self detonates hurling its contents 409 00:29:22,870 --> 00:29:24,733 toward the enemy in red. 410 00:29:26,240 --> 00:29:30,720 This weblike structure is the phagocyte's DNA. 411 00:29:30,720 --> 00:29:34,590 The cells sacrifices itself in a desperate effort, 412 00:29:34,590 --> 00:29:38,110 {\an8}taking advantage of its DNAs, sticky texture 413 00:29:38,110 --> 00:29:39,673 {\an8}to trap the enemy. 414 00:29:41,250 --> 00:29:45,870 {\an8}This video shows a phagocyte releasing its DNA. 415 00:29:45,870 --> 00:29:50,053 {\an8}You can see it in orange, just bursting out from that cell. 416 00:29:56,390 --> 00:30:00,530 Normally such attacks will not cause any clotting, 417 00:30:00,530 --> 00:30:03,020 but if there is a cytokine storm, 418 00:30:03,020 --> 00:30:06,080 overly active phagocytes in our bloodstream 419 00:30:06,080 --> 00:30:08,713 {\an8}self detonate in huge numbers. 420 00:30:10,340 --> 00:30:13,007 {\an8}(pensive music) 421 00:30:20,260 --> 00:30:23,410 {\an8}If too many DNA NETs have been cast, 422 00:30:23,410 --> 00:30:26,833 {\an8}they can even scatter blood components in the vicinity. 423 00:30:28,220 --> 00:30:32,080 {\an8}Lumps from these blood components form clots 424 00:30:32,080 --> 00:30:36,200 {\an8}and bind to each other to become larger and larger 425 00:30:36,200 --> 00:30:39,983 {\an8}to the point where they can completely block blood vessels. 426 00:30:44,630 --> 00:30:46,920 {\an8}Despite trying to save us, 427 00:30:46,920 --> 00:30:50,630 {\an8}these extreme suicidal attacks backfire. 428 00:30:50,630 --> 00:30:54,470 {\an8}By forming blood clots they can cause death. 429 00:30:54,470 --> 00:30:55,340 {\an8}COVID-19, as you know, 430 00:30:55,340 --> 00:30:57,530 {\an8}is caused by the SARS-2 coronavirus. 431 00:30:57,530 --> 00:30:58,850 {\an8}And this is a novel virus 432 00:30:58,850 --> 00:31:01,500 {\an8}that our bodies have not encountered before. 433 00:31:01,500 --> 00:31:02,610 {\an8}As a result of that, 434 00:31:02,610 --> 00:31:04,640 {\an8}the bodies don't know how to respond to it. 435 00:31:04,640 --> 00:31:07,610 {\an8}And so they are pulling out every tool 436 00:31:07,610 --> 00:31:10,200 {\an8}that we have in the toolbox to try and fight this infection. 437 00:31:10,200 --> 00:31:13,090 {\an8}What this means is the infection results 438 00:31:13,090 --> 00:31:16,400 {\an8}in unregulated amounts of inflammation. 439 00:31:16,400 --> 00:31:19,410 {\an8}And so inflammation can be very helpful in the beginning 440 00:31:19,410 --> 00:31:23,890 {\an8}to try and fight off infection and help to repair organs. 441 00:31:23,890 --> 00:31:25,680 {\an8}But if the inflammation is unregulated 442 00:31:25,680 --> 00:31:28,580 {\an8}and continues at high levels for long periods of time, 443 00:31:28,580 --> 00:31:31,760 {\an8}that inflammation can actually be damaging to the body. 444 00:31:31,760 --> 00:31:33,570 {\an8}Autopsy results have shown 445 00:31:33,570 --> 00:31:36,810 {\an8}that blood clots were the direct cause of death 446 00:31:36,810 --> 00:31:39,823 for a third of those who lost their lives. 447 00:31:42,560 --> 00:31:46,420 In order to prevent such excessive self detonations, 448 00:31:46,420 --> 00:31:49,343 cytokine storms must be suppressed. 449 00:31:51,800 --> 00:31:55,250 This is why drugs to dampen the immune response 450 00:31:55,250 --> 00:31:59,133 are being trialed as a potential treatment for COVID-19. 451 00:32:01,980 --> 00:32:06,490 Armed with a new strategy, hope is now on the horizon 452 00:32:06,490 --> 00:32:09,453 to help patients with the severest symptoms. 453 00:32:14,800 --> 00:32:18,060 Our immune system is our ultimate weapon 454 00:32:18,060 --> 00:32:20,303 in the fight against pathogens. 455 00:32:22,450 --> 00:32:25,280 And its presence can be traced way back 456 00:32:25,280 --> 00:32:27,823 in the evolutionary history of life. 457 00:32:30,560 --> 00:32:34,320 Approximately 550 million years ago, 458 00:32:34,320 --> 00:32:37,930 the Cambrian explosion created a diverse range 459 00:32:37,930 --> 00:32:39,423 of living organisms. 460 00:32:42,160 --> 00:32:45,490 Viruses were already in existence back then 461 00:32:45,490 --> 00:32:49,620 and are believed to have had spikes on their surfaces: 462 00:32:49,620 --> 00:32:54,133 the fake keys used to infect their hosts. 463 00:32:55,810 --> 00:32:59,703 Our evolutionary kin back then looked like this. 464 00:33:00,820 --> 00:33:04,990 It's believed that cells from our adaptive immune system, 465 00:33:04,990 --> 00:33:08,760 such as T cells and B cells came about 466 00:33:08,760 --> 00:33:11,570 as they endured these viral attacks 467 00:33:11,570 --> 00:33:15,093 with the ability to remember the enemies they encountered. 468 00:33:19,510 --> 00:33:24,160 {\an8}Although the coronavirus continues to cause havoc worldwide, 469 00:33:24,160 --> 00:33:27,440 studies have shown that viruses and hosts 470 00:33:27,440 --> 00:33:30,983 weren't always antagonistic during the course of evolution. 471 00:33:33,330 --> 00:33:36,350 There have been times when they co-existed, 472 00:33:36,350 --> 00:33:38,903 mutually taking advantage of one another. 473 00:33:42,840 --> 00:33:46,470 Some viruses are known to have embedded their genes 474 00:33:46,470 --> 00:33:49,183 into the DNA of cells they've infected. 475 00:33:55,900 --> 00:33:59,890 Viruses had, in fact, infected our ancestors 476 00:33:59,890 --> 00:34:02,703 and permanently left their mark in our DNA. 477 00:34:03,900 --> 00:34:08,900 As much as 8% of the human genome comes from viruses. 478 00:34:11,490 --> 00:34:15,800 And our bodies may have taken advantage of those viral genes 479 00:34:15,800 --> 00:34:18,683 to gain various important functions. 480 00:34:21,840 --> 00:34:23,293 {\an8}Here's an example. 481 00:34:24,450 --> 00:34:28,743 {\an8}The process of fertilization where sperm binds to an egg. 482 00:34:32,810 --> 00:34:35,640 The sperm carrying the father's DNA 483 00:34:35,640 --> 00:34:38,043 is about to enter the mother's egg. 484 00:34:39,400 --> 00:34:43,010 Because sperm is a foreign substance to the egg, 485 00:34:43,010 --> 00:34:46,133 it uses a special key to gain entry. 486 00:34:48,620 --> 00:34:53,133 It looks remarkably similar to how a virus enters a cell. 487 00:34:55,910 --> 00:34:59,260 Researchers believe that the fertilization process 488 00:34:59,260 --> 00:35:01,970 {\an8}may have taken advantage of viral genes 489 00:35:01,970 --> 00:35:04,937 {\an8}that had infected our ancestors long ago. 490 00:35:10,670 --> 00:35:13,360 Other functions are also thought to have evolved 491 00:35:13,360 --> 00:35:16,063 from viral genes picked up along the way, 492 00:35:17,510 --> 00:35:22,510 like the placenta, which enables babies inside the womb 493 00:35:23,430 --> 00:35:26,880 to get nutrition and oxygen from their mother, 494 00:35:26,880 --> 00:35:30,773 and some brain functions, which relate to longterm memory. 495 00:35:32,608 --> 00:35:35,191 (dreamy music) 496 00:35:39,590 --> 00:35:42,380 Through the long process of evolution, 497 00:35:42,380 --> 00:35:46,293 our immune system became stronger and more sophisticated. 498 00:35:52,600 --> 00:35:56,150 {\an8}Today, more than 40 different kinds of immune cells 499 00:35:56,150 --> 00:35:58,880 are working together in our bodies, 500 00:35:58,880 --> 00:36:01,523 {\an8}forming an elaborate defense network. 501 00:36:03,930 --> 00:36:08,060 {\an8}On the other hand, viruses have also been evolving, 502 00:36:08,060 --> 00:36:10,330 {\an8}gaining even more powerful traits 503 00:36:10,330 --> 00:36:12,543 {\an8}to break through our defenses. 504 00:36:14,890 --> 00:36:18,050 This current war between our immune network 505 00:36:18,050 --> 00:36:22,090 and the novel coronavirus is at its most intense 506 00:36:22,090 --> 00:36:24,513 in our shared evolutionary history. 507 00:36:31,150 --> 00:36:33,270 And new insights into the workings 508 00:36:33,270 --> 00:36:35,970 of our immune system and viruses 509 00:36:35,970 --> 00:36:40,143 are helping to uncover effective measures against COVID-19. 510 00:36:47,340 --> 00:36:48,173 Daddy! 511 00:36:48,173 --> 00:36:50,230 Baby, yes! 512 00:36:50,230 --> 00:36:52,910 {\an8}We love you. You're gonna beat this, okay? 513 00:36:52,910 --> 00:36:54,230 {\an8}We need you. 514 00:36:54,230 --> 00:36:55,640 {\an8}We can't wait for you to come home, Dad. 515 00:36:55,640 --> 00:36:56,850 {\an8}We love you. Kisses! 516 00:36:56,850 --> 00:36:58,223 {\an8}Love you, daddy! 517 00:36:59,770 --> 00:37:01,420 Michael Kevin was infected 518 00:37:01,420 --> 00:37:05,513 by the novel coronavirus and was in a coma for eight days. 519 00:37:09,040 --> 00:37:11,860 The first signs were similar to the flu, 520 00:37:11,860 --> 00:37:14,950 but within five days he had trouble breathing 521 00:37:14,950 --> 00:37:17,270 and was admitted to hospital. 522 00:37:17,270 --> 00:37:21,103 He was then transferred to the ICU and put on a ventilator. 523 00:37:23,280 --> 00:37:25,180 He was given three different drugs 524 00:37:25,180 --> 00:37:26,910 as part of a clinical trial, 525 00:37:26,910 --> 00:37:29,710 but his condition did not improve. 526 00:37:29,710 --> 00:37:31,313 He was running out of options. 527 00:37:35,240 --> 00:37:39,540 At that point, he was given a special treatment. 528 00:37:39,540 --> 00:37:41,230 Baby, how are you? 529 00:37:41,230 --> 00:37:42,470 You're looking good. 530 00:37:42,470 --> 00:37:45,400 He regained consciousness in four days 531 00:37:45,400 --> 00:37:48,089 and started recovering very quickly. 532 00:37:48,089 --> 00:37:52,172 (people cheering and applauding) 533 00:37:55,952 --> 00:37:59,014 {\an8}I'm so glad to be out of the coma. 534 00:37:59,014 --> 00:38:02,350 {\an8}So glad to be out of the hospital room. 535 00:38:02,350 --> 00:38:03,804 {\an8}I was ecstatic. 536 00:38:03,804 --> 00:38:07,407 It really (indistinct), where we were, it was our miracle. 537 00:38:10,190 --> 00:38:11,840 {\an8}Michael was saved by blood 538 00:38:11,840 --> 00:38:14,743 {\an8}from an individual who possessed special powers. 539 00:38:18,730 --> 00:38:19,660 {\an8}This is the man 540 00:38:19,660 --> 00:38:23,513 {\an8}who donated his blood to Michael - James Crocker. 541 00:38:24,680 --> 00:38:27,603 {\an8}He himself is a COVID-19 survivor. 542 00:38:29,290 --> 00:38:31,580 {\an8}Antibodies contained in James's blood 543 00:38:31,580 --> 00:38:34,543 were collected and injected into Michael's body. 544 00:38:35,770 --> 00:38:36,980 This special treatment 545 00:38:36,980 --> 00:38:39,913 is called convalescent plasma therapy. 546 00:38:41,170 --> 00:38:43,880 Antibodies are projectile weapons 547 00:38:43,880 --> 00:38:46,300 tailor-made by immune cells 548 00:38:46,300 --> 00:38:48,823 based on information from the virus. 549 00:38:49,930 --> 00:38:53,380 It is a powerful weapon that can specifically target 550 00:38:53,380 --> 00:38:55,963 the novel coronavirus to disable it. 551 00:38:57,710 --> 00:39:02,710 James's body was able to produce vast amounts of antibodies. 552 00:39:02,720 --> 00:39:05,800 When his antibodies were injected into Michael, 553 00:39:05,800 --> 00:39:08,623 they successfully eliminated the virus. 554 00:39:10,640 --> 00:39:13,200 This treatment is expected to save the lives 555 00:39:13,200 --> 00:39:14,920 of critically ill patients 556 00:39:14,920 --> 00:39:17,880 until a vaccine becomes available. 557 00:39:17,880 --> 00:39:21,200 And in August the U.S. Food and Drug Administration 558 00:39:21,200 --> 00:39:23,520 issued an emergency authorization 559 00:39:23,520 --> 00:39:26,593 for its use on hospitalized COVID patients. 560 00:39:28,550 --> 00:39:31,160 {\an8}After being discharged from the hospital, 561 00:39:31,160 --> 00:39:32,670 {\an8}Michael met up with James 562 00:39:32,670 --> 00:39:35,053 {\an8}to express his gratitude personally. 563 00:39:36,450 --> 00:39:38,350 I'm very grateful. 564 00:39:38,350 --> 00:39:41,479 It's really nice (indistinct) you came all the way here 565 00:39:41,479 --> 00:39:42,880 in South Florida. 566 00:39:42,880 --> 00:39:46,170 You have an opportunity to give, 567 00:39:46,170 --> 00:39:48,930 to help save the life of another person. 568 00:39:48,930 --> 00:39:51,453 Why wouldn't you want to do that? 569 00:39:52,510 --> 00:39:55,273 It feels so wonderful to give back. 570 00:39:58,040 --> 00:40:00,970 {\an8}The latest research has shown that some people 571 00:40:00,970 --> 00:40:04,540 {\an8}are able to produce vast amounts of antibodies, 572 00:40:04,540 --> 00:40:06,750 {\an8}enough to save the lives of patients 573 00:40:06,750 --> 00:40:08,313 {\an8}with very severe Simmons. 574 00:40:11,900 --> 00:40:16,403 Blood was collected from 149 COVID-19 survivors. 575 00:40:21,950 --> 00:40:24,630 This graph shows the levels of antibodies 576 00:40:24,630 --> 00:40:26,910 found in their blood samples. 577 00:40:26,910 --> 00:40:28,933 They vary from patient to patient. 578 00:40:34,610 --> 00:40:38,400 Some are able to produce 10 times more antibodies 579 00:40:38,400 --> 00:40:39,423 than the average. 580 00:40:42,330 --> 00:40:44,350 {\an8}I strongly believe it would help us 581 00:40:44,350 --> 00:40:48,940 {\an8}to understand exactly what happens in a person's body. 582 00:40:48,940 --> 00:40:50,530 {\an8}Why some people get really sick, 583 00:40:50,530 --> 00:40:52,270 {\an8}why others don't get really sick. 584 00:40:52,270 --> 00:40:55,480 {\an8}Some people did have higher levels 585 00:40:55,480 --> 00:40:57,520 {\an8}of neutralizing antibodies. 586 00:40:57,520 --> 00:41:01,490 {\an8}They're making really good antibodies. 587 00:41:01,490 --> 00:41:03,920 {\an8}They really are. They work very well. 588 00:41:07,026 --> 00:41:09,460 What is the difference between people 589 00:41:09,460 --> 00:41:12,570 who are able to produce large amounts of antibodies 590 00:41:12,570 --> 00:41:16,433 when infected by the novel coronavirus and those who don't? 591 00:41:18,150 --> 00:41:21,060 We don't know the exact answer yet, 592 00:41:21,060 --> 00:41:23,223 but scientists have a theory. 593 00:41:28,190 --> 00:41:31,543 Remember the moment when antibody production is triggered? 594 00:41:32,830 --> 00:41:37,470 Immune cells, holding viral fragments, handover enemy intel 595 00:41:37,470 --> 00:41:39,983 two units from our adaptive immune system. 596 00:41:43,810 --> 00:41:48,303 B cells then produce antibodies based on this information. 597 00:41:53,840 --> 00:41:56,960 The key here is the shape of the clasp 598 00:41:56,960 --> 00:41:59,333 jutting out from the messenger immune cell. 599 00:42:04,490 --> 00:42:05,670 We now know that there are 600 00:42:05,670 --> 00:42:09,110 more than 10,000 types of these clasps 601 00:42:09,110 --> 00:42:11,583 and we all have differently shaped ones. 602 00:42:19,320 --> 00:42:22,300 For example, some clasps are able to hold 603 00:42:22,300 --> 00:42:26,430 onto the fragment of the novel coronavirus perfectly, 604 00:42:26,430 --> 00:42:28,520 so they can keep sending out intel 605 00:42:28,520 --> 00:42:31,903 to allow large amounts of antibodies to be made. 606 00:42:33,120 --> 00:42:37,410 But in people who have differently shaped clasps, 607 00:42:37,410 --> 00:42:40,423 these can't grip the viral fragments as well. 608 00:42:41,410 --> 00:42:44,740 Unable to precisely pass on their message, 609 00:42:44,740 --> 00:42:48,093 only small amounts of antibodies can be made. 610 00:42:53,840 --> 00:42:57,230 Interestingly, we are beginning to understand 611 00:42:57,230 --> 00:42:59,920 that these differences may be associated 612 00:42:59,920 --> 00:43:02,363 with geography and ethnicity. 613 00:43:07,000 --> 00:43:12,000 {\an8}For example, in Africa, you can find many people with clasps 614 00:43:12,330 --> 00:43:14,110 {\an8}that are well suited for holding 615 00:43:14,110 --> 00:43:16,763 {\an8}onto fragments of the malaria parasite. 616 00:43:21,660 --> 00:43:24,000 Meanwhile, in Southeast Asia, 617 00:43:24,000 --> 00:43:27,510 there are lots of people who have the best kinds of clasps 618 00:43:27,510 --> 00:43:31,403 to grip fragments of bacteria, responsible for leprosy. 619 00:43:39,210 --> 00:43:41,530 Scientists believe that these differences 620 00:43:41,530 --> 00:43:45,370 come from variations in a gene called HLA, 621 00:43:45,370 --> 00:43:48,380 responsible for forming the shape of these clasps 622 00:43:48,380 --> 00:43:49,833 in our immune cells. 623 00:43:54,709 --> 00:43:56,150 {\an8}The middle door pathogens 624 00:43:56,150 --> 00:43:57,950 {\an8}have emerged throughout our history. 625 00:43:59,690 --> 00:44:01,690 {\an8}In different regions, in different ages. 626 00:44:04,510 --> 00:44:07,943 {\an8}That is why mankind has acquired different HLA types, 627 00:44:10,730 --> 00:44:12,543 to fight off different pathogens. 628 00:44:16,461 --> 00:44:19,044 (somber music) 629 00:44:21,980 --> 00:44:25,020 About 200,000 years ago, 630 00:44:25,020 --> 00:44:28,300 mankind born in Africa began to migrate 631 00:44:28,300 --> 00:44:30,253 to different parts of the world. 632 00:44:37,490 --> 00:44:41,040 {\an8}Wherever they went, our ancestors were attacked 633 00:44:41,040 --> 00:44:43,483 {\an8}by different viruses and pathogens. 634 00:44:47,250 --> 00:44:49,340 And after each attack, 635 00:44:49,340 --> 00:44:52,383 it's thought that the HLA gene adapted. 636 00:44:54,960 --> 00:44:57,760 So, the clasps suitable for new enemies 637 00:44:57,760 --> 00:44:59,843 can be created in us. 638 00:45:05,480 --> 00:45:07,100 The diversity of HLAs 639 00:45:07,100 --> 00:45:09,613 is our defense against the range of pathogens. 640 00:45:13,000 --> 00:45:15,930 So only those who excelled in the fight against them 641 00:45:15,930 --> 00:45:18,663 left their HLA types as a legacy to us. 642 00:45:24,400 --> 00:45:26,550 {\an8}We still don't know when or how 643 00:45:26,550 --> 00:45:29,330 {\an8}people like James managed to acquire 644 00:45:29,330 --> 00:45:31,410 {\an8}these kinds of special clasps 645 00:45:31,410 --> 00:45:33,913 {\an8}that can combat the novel coronavirus. 646 00:45:35,770 --> 00:45:38,580 Maybe their ancestors experienced infections 647 00:45:38,580 --> 00:45:41,090 from similar viruses in the past, 648 00:45:41,090 --> 00:45:42,970 so had acquired clasps, 649 00:45:42,970 --> 00:45:45,830 that just happened to be a perfect fit 650 00:45:45,830 --> 00:45:47,493 to the novel coronavirus. 651 00:45:49,990 --> 00:45:54,090 Each one of us has inherited a differently shaped clasp 652 00:45:54,090 --> 00:45:57,760 within our immune cells to fight viruses. 653 00:45:57,760 --> 00:46:00,130 It's a testament to our ancestors 654 00:46:00,130 --> 00:46:03,040 who had fought and survived an incredible variety 655 00:46:03,040 --> 00:46:05,883 of infectious diseases throughout evolution. 656 00:46:08,530 --> 00:46:11,780 And now cutting-edge medicine is attempting 657 00:46:11,780 --> 00:46:14,410 to harness this power from the few, 658 00:46:14,410 --> 00:46:17,913 so that lives all over the world can be saved. 659 00:46:21,600 --> 00:46:23,670 {\an8}At this research institute, 660 00:46:23,670 --> 00:46:27,710 {\an8}scientists are culturing immune cells collected from people 661 00:46:27,710 --> 00:46:32,023 who produce large amounts of novel coronavirus antibodies. 662 00:46:34,510 --> 00:46:38,200 They are hoping to produce antibodies in vast quantities, 663 00:46:38,200 --> 00:46:40,500 so they can be used to treat patients 664 00:46:40,500 --> 00:46:43,603 suffering from severe symptoms worldwide. 665 00:46:48,390 --> 00:46:51,580 Clinical studies are already underway, 666 00:46:51,580 --> 00:46:54,310 and researchers are hopeful that these treatments 667 00:46:54,310 --> 00:46:57,453 will be commercially available by the end of the year. 668 00:46:58,800 --> 00:47:03,250 These may become available earlier than vaccines. 669 00:47:03,250 --> 00:47:07,040 {\an8}I think it would make things in the laboratory 670 00:47:07,040 --> 00:47:09,430 {\an8}that would work better than what people are making. 671 00:47:09,430 --> 00:47:13,310 {\an8}And maybe those would work at very low concentrations 672 00:47:13,310 --> 00:47:16,290 {\an8}and make a practical way of delivering to people 673 00:47:16,290 --> 00:47:19,820 to protect them or help them if they're actually sick. 674 00:47:19,820 --> 00:47:21,960 This is definitely a possibility. 675 00:47:21,960 --> 00:47:24,300 And I think it's a very hopeful one, too. 676 00:47:24,300 --> 00:47:26,430 If anyone was sick and they were willing 677 00:47:26,430 --> 00:47:29,680 to donate their plasma to help other people 678 00:47:29,680 --> 00:47:33,143 and to help science, then yes, they are definitely heroes. 679 00:47:37,270 --> 00:47:40,380 The battle against COVID-19 continues 680 00:47:40,380 --> 00:47:42,293 with no end in sight. 681 00:47:43,870 --> 00:47:45,880 However our immune networks 682 00:47:45,880 --> 00:47:48,360 have been supporting us since birth 683 00:47:48,360 --> 00:47:51,933 and will do so until we take our last breath. 684 00:47:54,820 --> 00:47:57,923 {\an8}A woman is in labor in a hospital delivery room. 685 00:47:58,870 --> 00:48:01,330 {\an8}To prevent the spread of COVID-19, 686 00:48:01,330 --> 00:48:06,330 {\an8}her husband waits outside, watching the birth on screen. 687 00:48:06,335 --> 00:48:11,335 (gentle music) (nurses chattering) 688 00:48:15,320 --> 00:48:18,393 A new life joined the world today. 689 00:48:22,840 --> 00:48:25,870 Right from birth babies are exposed 690 00:48:25,870 --> 00:48:29,763 to many different pathogens like viruses and bacteria. 691 00:48:30,820 --> 00:48:35,070 But the baby's immune cells are not yet ready to fight back. 692 00:48:35,070 --> 00:48:38,103 What protects them is the mother's breast milk. 693 00:48:41,150 --> 00:48:43,840 For the first few days after birth 694 00:48:43,840 --> 00:48:47,280 breast milk contains large amounts of immune cells 695 00:48:47,280 --> 00:48:49,873 and antibodies, belonging to the mother. 696 00:48:50,900 --> 00:48:55,400 These all help the baby's own immune cells to develop 697 00:48:55,400 --> 00:48:59,373 and protects it from various bacteria and viruses. 698 00:49:00,390 --> 00:49:03,990 After several months, the baby's own immune network 699 00:49:03,990 --> 00:49:05,353 begins to kick in. 700 00:49:07,960 --> 00:49:10,810 In the years that follow, through exposure 701 00:49:10,810 --> 00:49:13,940 to different types of viruses and bacteria, 702 00:49:13,940 --> 00:49:18,083 our immune system continues to develop and grow stronger. 703 00:49:21,360 --> 00:49:23,430 It had been thought that our immunity 704 00:49:23,430 --> 00:49:27,673 reaches its peak in our 20s and then flattens out, 705 00:49:28,850 --> 00:49:31,233 gradually declining in our 70s. 706 00:49:35,210 --> 00:49:38,480 But during the current pandemic, 707 00:49:38,480 --> 00:49:40,690 remarkable recoveries have been observed 708 00:49:40,690 --> 00:49:42,753 in people across the world. 709 00:49:46,192 --> 00:49:48,870 {\an8}(group applauding) 710 00:49:48,870 --> 00:49:51,340 {\an8}In South Yorkshire in the UK, 711 00:49:51,340 --> 00:49:54,890 {\an8}Albert Chambers has recovered from COVID-19 712 00:49:54,890 --> 00:49:56,973 {\an8}and is being discharged from hospital. 713 00:49:59,550 --> 00:50:02,240 {\an8}He just turned 100 this year. 714 00:50:04,999 --> 00:50:09,373 What would you love to say to the nurses? 715 00:50:09,373 --> 00:50:13,473 There's nothing I can say but thank you very much, 716 00:50:13,473 --> 00:50:18,223 And I appreciate every bit of what they have done for me. 717 00:50:19,420 --> 00:50:21,900 Many places around the world 718 00:50:21,900 --> 00:50:23,740 have been reporting centenarians 719 00:50:23,740 --> 00:50:26,053 making astonishing recoveries. 720 00:50:27,031 --> 00:50:29,948 (group applauding) 721 00:50:32,260 --> 00:50:35,670 Recent studies suggest that in their bodies, 722 00:50:35,670 --> 00:50:39,333 something special is keeping their immune cells young. 723 00:50:46,410 --> 00:50:50,120 The human body is a remarkable and elaborate system 724 00:50:50,120 --> 00:50:51,453 full of mystery. 725 00:50:56,580 --> 00:51:00,840 Supported by specialist cells that protect our lives 726 00:51:00,840 --> 00:51:02,640 with their unique skills honed 727 00:51:02,640 --> 00:51:05,653 {\an8}over four billion years of evolution. 728 00:51:12,480 --> 00:51:15,320 The keys to overcoming this pandemic 729 00:51:15,320 --> 00:51:18,650 may be locked away in our bodies, 730 00:51:18,650 --> 00:51:21,367 and it could be hidden in you. 731 00:51:22,625 --> 00:51:25,458 (uplifting music)