Evidence of T cell receptor beta-chain patterns in inflammatory and noninflammatory bowel disease states

T cell activation, as defined by expression of relevant cell surface molecu les, such as the interleukin-2 receptor (CD25), is increased in many chroni c relapsing diseases, including inflammatory bowel disease (IBD). These T c ells are generally activated through contact of their clonotypic T cell rec eptor (TCR) with a peptide antigen presented by a major histocompatibility complex molecule. One of the putative antigenic contact sites for the TCR i s the third complementarity determining region (CDR3) of the TCR beta-chain variable region (TCRBV). Therefore, analysis of the TCRBV CDR3 provides in sight into the diversity of antigens encountered by a given T cell populati on. This study evaluated the TCRBV CDR3 usage of the activated intestinal l ymphocytes from human subjects with IBD, diverticulitis (inflammatory contr ol), and a normal tissue control. Public patterns, as demonstrated by share d TCRBV CDRS amino acid sequences of activated intestinal T cell subpopulat ions, were observed. In particular, a public pattern of TCRBV22, a conserve d valine in the fifth position, and use of TCRBJ2S1 or TCRBJ2S5 was present in three of four Crohn's disease subjects while not present in the ulcerat ive colitis subjects. However, the private patterns of TCRBV CDR3 region am ino acid sequences were far more striking and easily demonstrated in all in dividuals studied, including a normal noninflammatory control. Thus we conc lude that selective antigenic pressures are prevalent among an individual's activated intestinal lymphocytes.