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Which cells display class I major histocompatibility complex molecules?
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immune system
Stimulation of immune response by activated helper T cells. Activated by complex interaction with molecules on the surface of a macrophage or some other antigen-presenting cell, a helper T cell proliferates into two general subtypes, TH1 and TH2. These in turn stimulate the complex pathways of the cell-mediated immune response and the humoral immune response, respectively.
Class I major histocompatibility complex (MHC) molecules are expressed on the surface of almost every nucleated cell in an organism.12
These molecules play a critical role in the immune system by displaying peptide fragments for recognition by T lymphocytes, specifically aiding in the distinction between self and nonself. While class I molecules are found on nearly all nucleated cells, class II MHC molecules are restricted to specific antigen-presenting cells, such as macrophages and certain lymphocytes.12