5 doctors weighed in:

Why and how does the body reject a heart transplant?

5 doctors weighed in
3 doctors agree

In brief: Organs are foreign

Transplanted organs are treated by the body like foreign invaders (infections).
All solid organs transferred between humans are rejected by the immune system of the host. The one exception is identical twins. The rejection process can be halted in most cases with the use of powerful anti-rejection drugs that recipients are given for the life of the graft.

In brief: Organs are foreign

Transplanted organs are treated by the body like foreign invaders (infections).
All solid organs transferred between humans are rejected by the immune system of the host. The one exception is identical twins. The rejection process can be halted in most cases with the use of powerful anti-rejection drugs that recipients are given for the life of the graft.
Dr. Stuart Flechner
Dr. Stuart Flechner
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Dr. Robert Vogt Lowell
Pediatrics - Cardiology

In brief: It's "foreign"

Every cell in your body has a "label" (antigens) that identifies it as a part of you.
A transplanted organ has cells with different "labels" (the donors') so your immune system does not recognize those cells as being part of you and assumes that they are a threat to you (bacteria, virus, cancer cell, etc.) and destroys them by use of chemicals (anti-bodies) or by literally consuming them.

In brief: It's "foreign"

Every cell in your body has a "label" (antigens) that identifies it as a part of you.
A transplanted organ has cells with different "labels" (the donors') so your immune system does not recognize those cells as being part of you and assumes that they are a threat to you (bacteria, virus, cancer cell, etc.) and destroys them by use of chemicals (anti-bodies) or by literally consuming them.
Dr. Robert Vogt Lowell
Dr. Robert Vogt Lowell
Thank
Dr. Mary Callahan
Internal Medicine - Cardiology

In brief: Rejection

Your body rejects the heart transplant because it recognizes the tissue as foreign.
Immune cells invade the foreign tissue and can start to destroy it which can weaken the heart and make it fail. After the transplant you take special medicines to help prevent rejection, however, these medicines can also weaken your immune system.

In brief: Rejection

Your body rejects the heart transplant because it recognizes the tissue as foreign.
Immune cells invade the foreign tissue and can start to destroy it which can weaken the heart and make it fail. After the transplant you take special medicines to help prevent rejection, however, these medicines can also weaken your immune system.
Dr. Mary Callahan
Dr. Mary Callahan
Thank
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