Recognition of antigens by T lymphocytes

Area of Science:

• Immunology
• Molecular Biology
• Transplantation Science

Background:

• Mammalian B lymphocytes utilize monomeric IgM and IgD as antigen-specific receptors, composed of conventional immunoglobulin heavy and light chains.
• The precise structure of the T lymphocyte antigen receptor remains incompletely defined, suggesting novel components beyond conventional chains.

Purpose of the Study:

• To review current knowledge on B and T lymphocyte receptors.
• To discuss the characterization of the T cell receptor, including the proposed Tau-chain.
• To explore methods for inducing specific transplantation tolerance in adult animals.

Main Methods:

• Literature review of antigen-specific lymphocyte receptors.
• Discussion of the structural components of B and T cell receptors.
• Description of two methods for inducing specific transplantation tolerance.

Main Results:

• B cell receptors comprise conventional immunoglobulin heavy and light chains.
• T cell receptors likely involve a novel heavy chain, termed Tau-chain, and do not appear to use conventional light chains.
• Shared idiotypic determinants exist between B and T lymphocyte receptors.
• Potential links between T cell idiotypes, Tau-chains, and Major Histocompatibility Complex genes are discussed.

Conclusions:

• T cell receptors possess unique structural features, including the Tau-chain, differentiating them from B cell receptors.
• Understanding these receptor structures is crucial for developing strategies like transplantation tolerance induction.
• Targeting T cell idiotypic determinants offers a pathway for initiating specific autoimmune responses to achieve tolerance.