An analytical module of the ImmunoID NeXT Platform

Comprehensive Profiling of the TCR Repertoire

T-cells are one of two types of lymphocytes (the other being B-cells) that are active cellular participants in the adaptive immune system. T-cells express T-cell receptors (TCRs) on their surface, and these receptors function to recognize and bind to antigens that are presented by host cells. Since humans come into contact with a multitude of endogenous and exogenous antigens throughout their lives, the human immune system has had to evolve to match the structural diversity of these antigenic peptides to maintain health. This ability is facilitated by genetic rearrangements that occur in gene regions, known as variable (V), diversity (D), and joining (J) gene segments, that combine to form the complementarity determining region 3 (CDR3) responsible for the expression of specific TCR clonotypes. Variations in the particular V, D, and J gene segments used, precise points of recombination, and random nucleotide additions (N-diversity mechanisms) all contribute to the length and expansive sequence heterogeneity of CDR3 regions. Every TCR clonotype has a unique CDR3, which largely determines the antigen specificity of each TCR, and the total number of TCR CDR3 variations in a host is referred to as the TCR repertoire.