TZellUntergruppen

TZellUntergruppen, or T cell subgroups, are distinct functional lineages of T lymphocytes that arise from naive T cells after antigen exposure. They shape adaptive immunity through specialized cytokine production and effector functions. Subset differentiation is guided by antigen-presenting cells, cytokines, and co-stimulatory signals, yielding diverse roles in infection, autoimmunity, and cancer.

Major CD4+ helper subsets include Th1 (IFN-γ), Th2 (IL-4), Th17 (IL-17), and Tfh (IL-21); regulatory T cells (Treg, FOXP3) enforce tolerance. CD8+ T cells become cytotoxic lymphocytes that kill infected or malignant cells and form memory cells. Other subsets such as γδ T cells and invariant NKT cells provide rapid responses.

Lineage decisions hinge on transcription factors and cytokines: Th1/T-bet and IFN-γ; Th2/GATA3 and IL-4; Th17/RORγt and IL-17; Tfh/Bcl6 and IL-21; Treg/FOXP3 and TGF-β/IL-10. T cells express CD4 or CD8, with Tregs often CD25+. The T cell receptor (CD3) recognizes peptide antigens on MHC, aided by CD28 co-stimulation. Activated cells proliferate and populate tissues.

Clinically, T cell subgroups influence infection outcomes, cancer surveillance, autoimmunity, and allergy. Therapies that modulate T cell responses, such as checkpoint inhibitors and adoptive T cell transfer, illustrate the translational importance of TZellUntergruppen.