Preparation, purification and characterization of bovine Peyer's patch leukocytes.

An enzymatic technique for isolating bovine Peyer's patch leukocytes was developed. Enzymatic dissociation of Peyer's patches yielded a cell population rich in T and B lymphocytes containing 6-10% adherent accessory cells, as defined by morphology and nonspecific esterase staining. Analysis of Peyer's patch lymphocytes, using sheep erythrocyte rosetting and immunofluorescence with conventional antisera and monoclonal antibodies, showed that leukocytes were approximately 45% T cells and 25% Ig-positive B cells. The cell population contained functionally active T and B lymphocytes which proliferated in response to T and B cell mitogens and to exogenous human recombinant interleukin-2. The observed differences in patterns of Peyer's patch leukocyte responsiveness to these mitogens suggest some cellular heterogeneity of the bovine Peyer's patch.