A method of purifying feline T lymphocytes from peripheral blood using the plant lectin from Pisum sativum.

The binding properties of several plant lectins on feline peripheral blood lymphocytes (PBL) were examined by flow cytometry to reveal if any could serve as probes for identifying specific lymphocyte subclasses. Most of the lectins bound > or = 90% of PBL in a uniform manner. The exceptions were the lectins from Glycine max, Phaseolus limensis, and Dolichos biflorus, which bound only a proportion of the PBL. The differential binding of the lectins to lymphocyte subclasses was examined by comparing the staining of control PBL to T cell-depleted PBL. The lectins from Pisum sativum, Lens culinaris, succinylated Triticum vulgaris, and Dolichos biflorus stained T-depleted PBL more brightly than control PBL. Extensive cytofluorometric analyses of the binding properties of Pisum sativum agglutinin (PSA) on feline PBL and mesenteric lymph node cells indicated that feline B lymphocytes express more higher affinity surface receptors for PSA than do T lymphocytes. The higher affinity binding of PSA to B lymphocytes was further demonstrated by PSA-mediated cellular affinity chromatography. With this procedure it was possible to deplete PBL of B lymphocytes and to obtain pure populations of feline T lymphocytes.