Isolation and characterization of intraepithelial lymphocytes from rat small intestine.

A modified procedure for isolation of intraepithelial lymphocytes (IEL) from rat small intestine was developed which makes use of a protease inhibitor-phenyl methyl sulfonyl fluoride (PMSF) in the isolation medium. Yield and viability of IEL isolated in presence of PMSF were significantly higher as compared to those isolated in absence of PMSF. IEL isolated in presence PMSF demonstrated a significantly higher proliferative response to concanavalin A (con A) compared to those isolated in absence of PMSF. The natural killer cell activity of IEL population isolated in presence of PMSF using YAC-1 lymphoma cells as targets was also significantly higher compared to those isolated in absence of PMSF. Phenotypic analysis using monoclonal antibodies specific for rat T lymphocyte subsets revealed that majority of IEL were cytotoxic/suppressor phenotype with a minor subset of helper/inducer phenotype. The method described yielded a population of IEL which is suitable for further functional studies in vitro.