A patient undergoes a successful kidney transplant but is prescribed immunosuppressants for the rest of their life to prevent graft rejection. Which specific type of immune response is primarily responsible for this rejection, and to which broader category of immunity does it belong?

Step-by-step solution

Graft rejection in organ transplantation is primarily mediated by T-lymphocytes, which are responsible for the cell-mediated immune response (CMI). Cell-mediated immunity is a highly specific immune response that develops during an individual's lifetime and is characterised by immunological memory. Therefore, it is a sub-type of acquired immunity, not innate immunity. Humoral immunity, mediated by B-lymphocytes (antibodies), is not the primary cause of graft rejection. Answer: Cell-mediated immunity; Acquired immun