While many cell types in the thymus are able to induce negative selection of developing self-reactive thymocytes, bone marrow-derived antigen-presenting cells, such as macrophages and dendritic cells, appear to be the most important for this process. One likely reason for the prominent role of bone marrow-derived antigen-presenting cells in inducing negative selection of developing thymocytes is:
A) Bone marrow-derived antigen-presenting cells are the most abundant stromal cells in the thymus.
B) Bone marrow-derived antigen-presenting cells are very good at inducing mature T cell activation.
C) Bone marrow-derived antigen-presenting cells are highly phagocytic and have specialized mechanisms for presenting peptides on both MHC class I and class II.
D) Bone marrow-derived antigen-presenting cells are concentrated in the thymic medulla where negative selection is most prominent.
E) Bone marrow-derived antigen-presenting cells are hematopoietic in origin, so share the same genetic make-up as the developing thymocytes.

Question

Quizplus · Accepted Answer

Bone marrow-derived antigen-presenting cells, such as macrophages and dendritic cells, have specialized mechanisms for presenting peptides on both MHC class I and class II, allowing them to present a wide range of self-antigens to developing thymocytes. This, along with their high phagocytic capacity, makes them the most important cell type for inducing negative selection of self-reactive thymocytes.

While Many Cell Types in the Thymus Are Able to Induce