The Development of T Lymphocytes

These flashcards cover key concepts related to the development of T lymphocytes as discussed in the lecture notes.

Thymocytes

Developing T cells found in the thymus.

Positive selection

Process where developing T cells that recognize self-MHC are selected for survival.

Negative selection

Process where T cells that bind too tightly to self-antigens are eliminated.

MHC

Major Histocompatibility Complex; responsible for presenting self and non-self peptides to T cells.

Pre-TCR

Formed by the rearrangement of the β-chain gene and the pTα chain, guiding further T cell development.

Double-negative thymocytes

Thymocytes that do not express CD4 or CD8 and undergo TCR gene rearrangement.

Gene rearrangement

Process by which T cell receptor genes are altered to create functional receptors.

AIRE

Autoimmune Regulator; transcription factor important for negative selection by expressing non-thymic proteins in thymic epithelial cells.

Regulatory CD4 T cells

A subset of CD4 T cells that help maintain tolerance to self-antigens.

αβ T cells

A type of T cell characterized by the presence of α and β chains in their TCRs.

γδ T cells

A type of T cell characterized by the presence of γ and δ chains in their TCRs.

Thymic stroma

The supportive tissue in the thymus that provides a necessary environment for T cell development.

Receptor editing

Process allowing T cells to rearrange their TCR to prevent autoimmunity.

T cell progenitors

Immature cells originating from bone marrow that migrate to the thymus to develop into T cells.

Self-tolerance

The ability of the immune system to recognize self-antigens and avoid attacking them.

Thymic involution

The process where thymus size decreases and fatty tissue replaces thymic tissue after puberty.

Peripheral lymphoid organs

Organs where mature T cells encounter antigens and become activated.

CD4 T cells

A type of T cell that typically helps other immune cells by producing cytokines.

CD8 T cells

A type of T cell that typically kills infected or cancerous cells.

Clonal selection

The process by which specific T cells are selected for proliferation and differentiation based on their TCR's affinity for antigens.