Positive selection of lymphocytes refers to the
A) processing of an antigen by a macrophage.
B) proliferation of natural killer cells.
C) production of antigen-specific antibodies.
D) survival of pre-B and pre-T cells that are capable of an immune response.
E) replication of memory cells.

Question

Quizplus · Accepted Answer

Positive selection of lymphocytes, particularly in the context of T cells, occurs in the thymus and ensures that only those pre-T cells (and similarly for B cells in their respective organs) that can recognize self-MHC molecules while also being capable of responding to foreign antigens survive and mature. This process is crucial for developing a functional adaptive immune system that can distinguish between self and non-self. Choices A, B, C, and E describe other aspects of immune function but not the specific process of positive selection.

Positive Selection of Lymphocytes Refers to the