CELLULAR DISTRIBUTION OF THE
MHC ANTIGENS
Class I MHC molecules (HLA-A, B, and C alleles
in humans and H2-K, D, and L alleles in mice) are expressed on all nucleated
cells with only two exceptions: neurons and striated muscle cells. They are
particularly abundant on the surface of lymphocytes (1,000–10,000
molecules/cell).
Class II MHC molecules (the I-A and I-E alleles
of the mouse H2 complex and the DP, DQ, and DR alleles of the human HLA system)
are exclusively expressed in two groups of leukocytes: B lymphocytes and cells
of the monocyte-macrophage family, which includes all antigen-presenting cells
(Langerhans cells in the skin, Kupffer cells in the liver, microglial cells in
the central nervous system, and dendritic cells in the spleen and lymph nodes).
While resting T lymphocytes do not express MHC-II molecules, these antigens can
be detected after cell activation. Several other types of cells have been shown
to express MHC after activation. It must be stressed that all cells expressing
class II MHC simultane-ously express class I MHC.
Related Topics
Privacy Policy, Terms and Conditions, DMCA Policy and Compliant
Copyright © 2018-2024 BrainKart.com; All Rights Reserved. Developed by Therithal info, Chennai.