T Cells Lecture Notes

Vocabulary flashcards about T Cells. These flashcards are designed to help you review the key terms and concepts related to T cells, their development, and function.

SCID (Severe Combined Immunodeficiency)

A type of primary immunodeficiency where patients lack T cells, making them highly susceptible to infections.

Cell-Mediated Immunity

Immunity mediated by T cells, involving cell-to-cell interactions.

Helper T Cells

T cells that help other cells, such as B cells and macrophages, by producing cytokines and facilitating cell-to-cell interactions; also known as CD4 T cells.

Cytotoxic T Cells

Also known as CD8 T cells, directly kill infected cells, particularly those infected with intracellular pathogens like viruses and bacteria.

T Cell Receptor (TCR)

The receptor on T cells that recognizes peptides presented by MHC molecules.

MHC Restriction

The phenomenon where T cells can only recognize antigens presented by the body's own MHC molecules.

Co-receptors (CD4, CD8)

Molecules that bind to MHC molecules and help initiate signaling in T cells; examples include CD4 and CD8.

ITAMs (Immunoreceptor Tyrosine-Based Activation Motifs)

Regions within the CD3 molecules and zeta chains of the TCR complex that are crucial for cellular signaling.

Thymocytes

Developing T cells in the thymus.

Positive Selection

Process in T cell development where T cells are tested for their ability to recognize self-MHC molecules.

Negative Selection

Process in T cell development where T cells that react strongly to self-antigens are eliminated to prevent autoimmunity.

mTECs

Medullary thymic epithelial cells; specialized cells in the thymus that express tissue-restricted antigens to test T cells for self-reactivity.