The following are some types of GvHD:
- Hyperacute rejection: A hyperacute rejection is caused by preformed HLA antibodies or naturally occurring ABO antibodies, resulting in immediate rejection.
- Acute rejection: An acute rejection is caused by primary immune responses that occur within days to weeks post-transplant. The main cause of failure here is CD8 T lymphocytes that are directed toward the donor. Potential mismatches of HLA antigens are found by the recipient's immune system, and eventually, the humoral response will be activated.
- Chronic rejection: A chronic rejection results in the thickening of blood vessels that restrict the lumen and decreased blood flow to and from the organ. This occurs months to years after transplantation.
Graft versus leukemia (
GvL effect) is a potential outcome where the graft recognizes host tumor cells as foreign and kills the cancerous cells and tissue. This prevents relapse and allows donor tissues to grow, which is generally beneficial and does not turn into GvHD.
