September 30, 2015 - T Cell Physiology Flashcards
Variable Region
Binds the antigen.
T Cell Selection
Occurs in the Thymus.
Very few cells actually “graduate” the thymus. TCRs that can’t interact with self MHC molecules are destroyed, and TCRs that are too attracted to self MHC are destroyed.
Subsets of CD4 T Cells
TH1 - Intracellular microorganisms
TH2 - Parasitic infections
TH17 - Extracellular bacteria and fungi
Treg - Tolerance
TH1 Cells
Important for stimulating macrophages and stimulating antibody production.
Important for the ingestion and killing of INTRAcellular microbes.
TH2 Cells
Stimulates the production of IgE antibodies as well as activating eosinophils.
Helpful for fighting helminth parasites.
TH17 Cells
Capable of recruiting neutrophils and causing inflammation. Also are implicated for their role in autoimmune diseases.
Treg Cells
Immunosuppressive cells.
Central Tolerance
Learned in Thymus.
Peripheral Tolerance
When mature T cells recognize self-antigens in peripheral tissues (that weren’t in the Thymus). Inactivation of the cell occurs normally.
Autoimmunity
The loss of immunological tolerance.