Electrokinetic properties of lymphocytes separated from mouse Peyer's patches.

The aim of the present study was to characterize the electrophoretic mobility (EPM) of lymphocyte populations isolated from murine Peyer's patches (PP). Electrokinetic properties were investigated using both analytical and preparative cell electrophoresis and conventional serologic and mitogenic markers for B and T cells were determined in parallel. In CBA mice, PP cells which included 44% surface-immunoglobulin positive (sIg +) cells and 23% Thy-1-2-positive cells, were found to be composed of two distinct electrophoretic populations. The major one (66% of PP cells) with a mean EPM = 0.70 μms V cm was designated as the low-mobility (LM) population, the other one with a mean EPM = 1.16 μmsaV cm was designated as the high-mobility (HM) population. LM cells were encountered in lower frequency (9%) in B lymphocyte-depleted, PP (5% sIg +) from cyclophosphamide-treated CBA mice but were preponderant (92%) in the B lymphocyte-enriched (80% sIg +) nylon-adherent PP cells. In contrast, HM cells made up the majority of cyclophosphamide-resistant PP cells and of nylon-non adherent PP cells which were shown to be enriched in T lymphocytes (70 and 63% Thy-1-2 cells respectively). On the other hand, following fractionation of CBA PP cells by free-flow preparative electrophoresis, sIg + cells were distributed in the LM region and Thy-1-2 cells in the HM region. Moreover, in T lymphocyte-deficient athymic nude mice, PP cells which were 70% sIg +, were found to be exclusively of LM type (mean EPM = 0.77 μm s V cm). Thus, although both electrophoretic populations included sIg and Thy-1-2-negative elements, it appears that in murine PP as in spleen, most B lymphocytes are endowed with a low EPM and T lymphocytes with a higher EPM.