Part 2 Flashcards
Effective on endogenous Ag or Ag that attack from the inside like tumor, virus and intracellular pathogens.
Class I HLA
Example: Adenovirus and Herpes simplex block antigen presentation making it undetected by the immune system.
Class I HLA
Expressed in all nucleated cells (highest in lymphocytes and undetected in liver hepatocytes).
Class I HLA
Synthesized in the endoplasmic reticulum
Class I HLA
Each class I antigen is a glycoprotein dimer made up by two non-covalently linked polypeptide chains.
Class I HLA
For protection against viruses and parasites
Class I HLA
MHC Class I deficient diseased cells trigger and activate NK cells.
Class I HLA
Nonclassical Class I antigens: E, F, G (not expressed in cell surface and do not function of antigen recognition, Grantigens is expressed in trophoblast cells during 1st trimester or pregnancy to ensure tolerance for the fetus by protecting placental tissue from NK cells.
Class I HLA
HLA-B8-increased resistance to HIV infection.
Class I HLA
Altered cell
Tumor cell
Virally infected cell
T cell (CD8)
TnF- Beta -
Lymphotoxin
МНС Class I
can not respond to virus cell. It must be complexed with HLA
T-cell
Effective on exogenous Ag (exist outside the host cell and are engulfed by phagocytosis) like bacteria.
Class II HLA
Found in APCs: B- lymphocytes, monocytes ,macrophages and dendritic cells.
Class II HLA
Synthesized in the endoplasmic reticulum
Class II HLA
MHC Class II genes: HLA-DP,DQ and DR
Class II HLA
Non-Classical 11 genes: DM, DN and DO (play a role in regulation by antigen processing).
Class II HLA
HLA- A, B & C
Class I
HLA-DN, DO, DP, DQ, & DR
Class II
Nucleated cells
Class I
B cells, macrophages, other antigen presenting cells, activated T cell
Class II
To present Endogenous antigen to CYTOTOXIC T cell
Class I
To present Endogenous antigen to HELPER T
Class II
Target cell - Cytotoxic T cell.
Class I
APCs - Helper T cell
Class II
