Question

A recipient’s body rejects grafts due to the following type of immunity:

• A. Innate immunity
• B. Humoral immunity
• C. Cell-mediated immunity
• D. Either b or c

Answer 1

Answer:

C. Cell-mediated immunity

• The type of immunity responsible for graft rejection by a recipient body is primarily cell-mediated immunity.

• The immune system of a recipient recognizes transplanted cells as foreign and initiates an immune response to eliminate them.

• This immune response involves the activation of T cells, specifically cytotoxic T lymphocytes (CTLs), which directly attack and destroy the transplanted cells.

• Cell-mediated immunity, which is a component of adaptive immunity, plays a significant role in graft rejection.

• CTLs recognize and target the foreign antigens present in the transplanted cells, leading to their destruction.

• This process involves the activation of T cells, antigen presentation by major histocompatibility complex (MHC) molecules and the release of cytotoxic molecules by the activated T cells.