One type of bare lymphocyte syndrome is caused by a genetic defect in MHC class II transactivator (CIITA),which results in the inability to synthesize MHC class II and display it on the cell surface.The consequence of this would be that

Question

Quizplus · Accepted Answer

MHC class II is required for CD4 T cells to respond to extracellular pathogens. Without MHC class II, CD4 T cells cannot function properly and the immune response to extracellular pathogens is greatly compromised. B cells can still develop and CD8 T cells are not affected because they respond to intracellular pathogens that are presented on MHC class I molecules, not MHC class II. Intracellular infections can still be eradicated by CD8 T cells and other immune cells. The inability to synthesize MHC class II also means that peptides cannot be loaded onto MHC molecules in the lumen of the endoplasmic reticulum, but this is not the most significant consequence of the defect.

One Type of Bare Lymphocyte Syndrome Is Caused by a Genetic