current position:Home>Pig heart transplant the first person died, pig heart hidden pig virus

Pig heart transplant the first person died, pig heart hidden pig virus

2022-05-07 13:19:4836kr

This year, 3 month 8 Japan , The world's first patient to receive a pig heart transplant died two months after the operation , No definite cause of death was found at that time .

5 month 4 Japan 《 MIT technology review 》 reports , Transplant experts say the pig heart carries a swine virus , This may be the reason for the deterioration of the patient's condition .

Map technologyreview

“ Rock stars ” Two months later

It's a transplant called David · Bennett (David Bennett) Of 57 Year old male , He has end-stage heart disease , It does not meet the conditions for human heart transplantation and the use of cardiac assist devices . therefore , Xenotransplantation became Bennett's only hope for survival , According to a statement provided by the University of Maryland School of Medicine , He said the day before the operation :“ Or die , Or a transplant . I want to live .”

Surgery this year 1 month 7 day , when 7 Hours . The pig that provided the heart during the operation came from a biotechnology company in Virginia Revivicor, What's special is , The pig was genetically edited to avoid rejection .

A few days later , Bennett can sit up in bed . Surgeon Bartley · Griffith (Bartley Griffith) Indicates that the new heart is working well , Like a “ Rock stars ”, This shows that the heart of gene editing animals can play a role in the human body and does not immediately cause rejection .

The next few weeks , The transplanted heart works well in Bennett , No rejection . During that time , Bennett can spend time with his family 、 Receive rehabilitation treatment , I also sat up and watched the super bowl with physiotherapists , And often talk about wanting to go home and take care of his dog Lucky.

But after operation 40 Days or so , Bennett's condition began to deteriorate , And finally died two months after operation . A hospital spokesman said , No definite cause of death was found , The researchers plan to conduct a detailed analysis and publish the results .

Bennett after surgery | UMSOM /Handout via REUTERS

Pigs have a pig virus in their hearts

4 month 20 Japan , At the American Transplant Society webinar , Surgeon Griffith described the process of discovering and fighting the pig virus .

Postoperative 20 days , Doctors found signs of porcine cytomegalovirus in Bennett's blood test , But the value was very low , And pigs that provide organs should not carry pathogens , So doctors think the test results may be inaccurate . After operation 43 days , Bennett's state has deteriorated , Having difficulty breathing and unwilling to talk to a doctor .

At this time , Doctors think Bennett is infected , Decided to use the antiviral drug cidofovir , And inject human immunoglobulin to resist infection .24 Hours later, , Bennett is getting better , But a week later, it worsened again and no longer improved .

Griffith thinks , Porcine cytomegalovirus entered Bennett's body with the pig heart , The viral infection then worsened and triggered a severe inflammatory reaction in the patient , This leads to edema in the pig heart 、 Fibrosis , Eventually irreversible heart failure .

What problems does the pig virus bring ?

Pathogens carried by pigs are transmitted to humans through transplanted organs , This has always been a concern in xenotransplantation .

The most worrying situation is , Porcine virus has adaptive changes in patients , Then spread it to doctors and nurses , Then it caused a pandemic .

however , In Bennett's case , Transplant infection expert Jay · Fishman (Jay Fishman) It is believed that the cytomegalovirus found in pig heart will not infect human cells , There is no need to worry about further transmission between humans .

The problem is that porcine cytomegalovirus may damage transplanted organs and patients . Two years ago. , Researchers have reported , If a pig heart transplanted to a baboon carries the virus , Baboons die a few weeks after surgery , The heart without virus can last for more than half a year . Researchers believe , After the pig's heart leaves the pig's body , The virus in it is no longer suppressed by the pig immune system , The baboon's immune system is inhibited by drugs and can't work , So the virus will replicate in large numbers . In theory , A similar situation may occur in humans .

Avoid pigs carrying pathogens that affect patients , Strict microbiological monitoring and reporting are required 、 Development of infectious diagnostic analysis 、 Reproduction and Quarantine of animals of transplant origin , Including the detection and selection of pigs 、 Control breeding conditions 、 Early weaning and embryo transfer .

The pig that provided Bennett with the heart , Seems to have been tested for a virus in the nose , The results were negative . But the virus usually lurks deeper in pigs , It suggests that more stringent testing is needed in the future . Regarding this , Biotechnology companies that provide pigs Revivicor Declined to comment .

It's failure , Or success ?

For the exact cause of Bennett's death , It's too early to make a conclusion . Doctors think there are other possibilities , For example, human immunoglobulin injected during treatment may also damage the pig heart , Because later tests showed , This contains anti pig antibodies .

The discovery of the swine virus is not necessarily entirely bad news , Because virus infection can be prevented , Transplantation rejection is the biggest obstacle of animal organ transplantation . The main difficulty is that pigs and humans have very different genes , Xenotransplantation across species can lead to severe immune rejection .

A variety of antibodies against foreign bodies are stored in the human body , It also includes anti porcine antibodies , Within minutes to hours after the pig heart enters the human body , These antibodies bind to antigens on pig cells , Activate a series of factors , Quickly lead to pig cell damage and vascular damage , The pig's heart is out of function , Finally, the migration failed . This process is also known as hyperacute xenograft rejection .

The next few days to weeks , Immune cells in the body are also involved in attacks , Directly lead to pig cell death and inflammatory reaction ( Cell xenograft rejection ), Then there is a longer-term chronic rejection . As opposed to human to human allografts , Human rejection of pig organs is more intense .

This time to avoid rejection , Researchers knocked out the genes that cause human rejection in pigs , And added genes that help the human immune system accept the pig heart . Bennett's postoperative examination showed , The pig heart basically did not cause serious rejection .

in other words , If virus infection can be avoided in the future , Maybe transplants can work for years . This may advance relevant research , Let researchers explore pig organ transplantation again in the near future .

Bennett's operation | UMSOM /Handout via REUTERS

Many new treatments have gone through a long trial phase , For patients who are the first to try a new treatment , Their own lives may not change dramatically , But in the end, their contribution may change the whole direction of medical development . The details provided by Bennett , It will remind us how far we are from alleviating organ shortage .

Dr Griffith called Bennett a brave volunteer , And said :“ Like any transplant in the world , The operation brought valuable insights , It is expected to support transplant surgeons to improve surgical prognosis , And may help save the lives of future patients .”

Bennett's son also hopes that his father's experience will eventually help patients with transplanted pig organs prolong their lives :“ We hope this story can be the beginning of hope , Not the end .”

reference

[1]https://www.technologyreview.com/2022/05/04/1051725/xenotransplant-patient-died-received-heart-infected-with-pig-virus/

[2]https://www.theguardian.com/us-news/2022/jan/10/maryland-pig-heart-transplant-human-medical-first

[3]https://apnews.com/article/pig-heart-transplant-6651614cb9d73bada8eea2ecb6449aef

[4]https://edition.cnn.com/2022/01/10/health/genetically-modified-pig-heart-transplant/index.html

[5]Lu T, Yang B, Wang R, Qin C. Xenotransplantation: Current Status in Preclinical Research. Front Immunol. 2020;10:3060.

[6]Platt JL, Piedrahita JA, Cascalho M. Clinical xenotransplantation of the heart: At the watershed. J Heart Lung Transplant. 2020;39(8):758-760.

[7]Reichart B, Längin M, Radan J, et al. Pig-to-non-human primate heart transplantation: The final step toward clinical xenotransplantation? J Heart Lung Transplant. 2020;39(8):751-757.

[8]Cooper DKC, Gaston R, Eckhoff D, Ladowski J, Yamamoto T, Wang L, Iwase H, Hara H, Tector M, Tector AJ. Xenotransplantation-the current status and prospects. Br Med Bull. 2018;125(1):5-14.

[9]https://www.bbc.com/news/health-58993696

[10]https://www.usatoday.com/story/news/health/2022/03/09/human-pig-heart-transplant-patient-dies/9437650002/

[11]https://www.medschool.umaryland.edu/news/2022/IN-MEMORIAM-David-Bennett-Sr.html

This article is from WeChat official account. “ The nut ”(ID:Guokr42), author : Doctor Dai 、 Li Xiaoqiu , edit :odette,36 Krypton authorized release .

copyright notice
author[36kr],Please bring the original link to reprint, thank you.
https://en.fheadline.com/2022/127/202205071307462592.html

Random recommended