Hormones Of Heart Kidney And Gastrointestinal Tract

The question asks which immune response is responsible for the rejection of a kidney graft. To answer this, we need to understand the different types of immune responses and their roles:

1. Auto-immune response: This occurs when the body's immune system mistakenly attacks its own cells and tissues as if they were foreign invaders. It is not directly involved in the rejection of transplanted organs like a kidney graft.
2. Humoral immune response: This involves antibodies produced by B-cells that target free-floating pathogens in body fluids. While antibodies can be involved in graft rejection, the primary mechanism is the activation of T-cells, which is part of cell-mediated immunity.
3. Inflammatory immune response: This response is part of the innate immune system, involving the recruitment of various immune cells to sites of tissue injury or infection. It helps contain an infection but is not specific to the rejection of transplanted tissues.
4. Cell-mediated immune response: This involves T-cells, particularly cytotoxic T-lymphocytes, which directly attack and destroy cells identified as foreign, such as those from a transplanted organ. This response is the primary cause of transplant rejection because donor tissues often present antigens that the recipient's immune system recognizes as foreign.

Given this information, the correct answer is the cell-mediated immune response because it is primarily responsible for the recognition and rejection of foreign tissues, including kidney grafts.