Oligoclonal Expansion and CD1 Recognition by Human Intestinal Intraepithelial Lymphocytes

A human intestinal intraepithelial lymphocyte (IEL) T cell line was established from jejunum to characterize the structure and function of the αβ T cell antigen receptors (TCRs) expressed by this population. Single-sided polymerase chain reaction (PCR) amplification cloning and quantitative PCR amplification of the TCR chains from the cell line and from fresh IELs demonstrated that IELs were oligoclonal. The IEL T cell line exhibited CD1-specific cytotoxicity and a dominant IEL T cell clone was CD1c-specific. Thus, human jejunal intraepithelial lymphocytes are oligoclonal and recognize members of the CD1 gene family.