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Updated: Nov 23, 2025

Visualizing Antigen Specific CD4+ T Cells using MHC Class II Tetramers
Published on: March 6, 2009
The Many Faces of CD4+ T Cells: Immunological and Structural Characteristics
Demetra S M Chatzileontiadou1, Hannah Sloane1, Andrea T Nguyen1
1Department of Biochemistry and Molecular Biology, Biomedicine Discovery Institute, Monash University, Clayton, VIC 3800, Australia.
Abstract:
As a major arm of the cellular immune response, CD4+ T cells are important in the control and clearance of infections. Primarily described as helpers, CD4+ T cells play an integral role in the development and activation of B cells and CD8+ T cells. CD4+ T cells are incredibly heterogeneous, and can be divided into six main lineages based on distinct profiles, namely T helper 1, 2, 17 and 22 (Th1, Th2, Th17, Th22), regulatory T cells (Treg) and T follicular helper cells (Tfh). Recent advances in structural biology have allowed for a detailed characterisation of the molecular mechanisms that drive CD4+ T cell recognition. In this review, we discuss the defining features of the main human CD4+ T cell lineages and their role in immunity, as well as their structural characteristics underlying their detection of pathogens.
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