Question

What type of immune response typically leads to acute rejection of transplanted tissues, such as a kidney transplant?

A. Humoral immune response against MHC antigens
B. Polyclonal T-cell response against donor MHC antigens
C. Chronic rejection involving donor endothelial cells
D. Activation of memory B cells against donor epitopes

Answer 1

Acute rejection of transplanted tissues is typically caused by a polyclonal T-cell response against donor MHC antigens, which leads to a cytotoxic T-cell response and organ rejection. The correct option is B.

Step-by-step explanation:

The type of immune response that typically leads to acute rejection of transplanted tissues, such as a kidney transplant, is a polyclonal T-cell response against donor MHC antigens.

Specifically, when a donor organ expresses MHC molecules that are different from the recipient, the recipient's immune system often mounts a cytotoxic T-cell response to the organ and rejects it.

This response is due to MHC polygeny and MHC polymorphism, which cause a diversity of MHC molecules and alleles. Therefore, the correct answer is B. Polyclonal T-cell response against donor MHC antigens.