Tolerance and Self-Reactivity in Vγ1.1Cγ4 Transgenic Mice

Abstract

Immunological tolerance is the process of inhibiting or eliminating lymphocytes that recognize self-derived antigens. By removing potentially harmful self-reactive clones, this mechanism allows for the random generation of a diverse repertoire of T-cells capable of responding to foreign pathogens. Although all self-reactive T-cells should be removed from the repertoire, it is quite clear from many recent studies that a significant fraction of T-cells bearing γδ T-cell receptors (TCR) recognize self-derived antigens in normal healthy mice. The presence of self-reactive T-cells in healthy animals presents a paradox which may be explained by understanding the transient expression of the antigens (e.g., MHC class 1b, Heat Shock Proteins) that have been identified for γδ T-cells thus far. Data from experiments with VγI. 1C-γ4 transgenic mice demonstrating the presence of self-reactive 78 T-cells and their influence on lymphoid development and immune surveillance will be examined in this review.

Key Words:

• T-cell
• thymus
• transgenic
• tolerance
• self-reactivity