Transplanted pig kidney works in US man's body for record 271 days

Fonte da imagem, Kate Flock/Massachusetts General Hospital. Legenda da imagem, Paciente Tim Andrews (centro) com Dr. Tatsuo Kawai (esquerda) e Dr. Leonardo Riella (direita).

• Are pigs the future of organ transplants?Published13 March 2022.

Homem que recebeu primeiro rim de porco em transplante morre Publicado 12 de maio de 2024.

Health and science correspondent A kidney transplanted from a pig has worked inside a patient for 271 days – the longest on record, say US doctors.

Tim Andrews said the transplant gave him "hope" and spared him months of needing to go to hospital to have his blood filtered by a dialysis machine.

A equipe do hospital Mass General Brigham diz que seu trabalho mostra que órgãos de porco podem ser usados como uma “ponte” até que um transplante humano esteja disponível.

Mas o órgão de porco acabou falhando e foi retirado, obrigando Andrews a passar por um curto período de diálise antes de encontrar um doador.

Doctors and scientists are exploring xenotransplantation – using organs from other species – due to shortages of organs for transplants.

In the US, around 100,000 people are waiting for a kidney while only 25,000 transplants occur each year. More than 7,000 people in the UK are on the kidney transplant list.

Andrews foi informado de que poderia levar sete anos para chegar ao topo da lista, mas que as pessoas vivem apenas cinco anos, em média, em diálise.

I had a little bit of a shortage of time… it becomes very depressing," he said.

Mas ele descreveu a ideia de um transplante de porco como 'esperança' e a 'luz no fim do túnel.

Hope is the biggest thing, the chance to be free from the [dialysis] machine and live your life.

Image source, Kate Flock/Massachusetts General HospitalImage caption, Tim Andrews preparing for surgery in January 2025.

Fonte da imagem, Kate Flock/Massachusetts General Hospital Legenda da imagem, O rim do doador havia sido colhido de um porco geneticamente modificado para torná-lo adequado à doação humana.

Image source, Kate Flock/Massachusetts General HospitalImage caption, Surgeons attached the pig kidney to the blood vessels inside Tim Andrews' body so the organ could filter the blood.

Fonte da imagem, Kate Flock/Massachusetts General HospitalLegenda da imagem, Um emocional Tim Andrews e sua esposa Karen compartilham um abraço enquanto saem do Massachusetts General Hospital em 1 de fevereiro de 2025.

Pigs are seen as the ideal animal for xenotransplantation. Their organs are roughly the right size and there have been years of experience farming them.

But you cannot just pop down to the farm and take a kidney from a pig and put it into a person. The human body would immediately identify the organ as foreign and launch a devastating immune assault that would destroy the kidney.

Ele se tornaria preto em minutos, enquanto buracos são rasgados em cada célula e o órgão coagula de dentro.

So researchers have developed Yucatan miniature pigs that have gone through 69 genomic modifications to "humanise" their organs.

These modifications strip out some features of pig cells that our immune system spots and attacks; add some human DNA that acts like camouflage netting to help hide the pig tissue from the immune system and further tweaks disable viruses that hide inside pig DNA to prevent infection.

Andrews had end stage kidney disease as a result of type 2 diabetes and his kidney's were failing.

Ele tinha 66 anos quando realizou o xenotransplante em 25 de janeiro de 2025.

O rim de porco transplantado funcionou imediatamente, segundo detalhes recém‑publicados na revista médica Lancet, externo.

The kidney continued to function for 271 days until it was removed in October that year. Tim then needed dialysis for 82 days until he had an organ from a donor in January of this year.

Dr Leonardo Riella, from the centre for transplantation sciences at Mass General Brigham said the shortage of organs available for transplant meant " we are in a crisis.

We are working really hard to bring hope and we truly feel that xenotransplantation can be an alternative for patients who don't have a living donor where we could potentially bypass dialysis and get them to a transplant," he said.

Houve sinais precoces de que o órgão de Andrews estava sendo rejeitado pelo sistema imunológico, mas isso foi tratado com sucesso ajustando sua medicação.

However, after around six months the blood vessels in the kidney started to become damaged and the organ inflamed and then it started to fail.

Não está claro exatamente por que, pois não havia sinais de anticorpos atacando o rim do porco.

Este caso ilustra tanto a promessa quanto os desafios restantes da xenotransplante renal clínico.