Delineation and quantitation of human peripheral blood lymphocyte subpopulations by electrophoretic mobility and role of surface charge in cell to cell interaction.

A modified procedure is proposed for determination of electrophoretic mobility (EPM) of lymphocytes which enables readings on 200 cells from a sample size of 5 x 106 lymphocytes. In normal human peripheral blood, B lymphocytes (bearing surface immunoglobulin and receptor for activated C3) were found to carry the lowest charge (0.94 +/- 0.05 mu/sec/V/cm). Their number on the EPM basis was 16.9 +/- 4.2%. Two subpopulations of T lymphocytes, one carrying high charge (TH) with a mean EPM of 1.26 +/- 0.04 mu/sec/V/cm and the other carrying lower charge (TL) with a mean EPM of 1.11 +/- 0.03 mu/sec/V/cm were discernible. The former subpopulation of T cells formed spontaneous rosettes with SRBC in 10 min and the latter represented the remaining T lymphocytes which formed rosettes with 24 hr of incubation with SRBC. The number of early rosette-forming cells increases from 69 to 89% when T cells were incubated with neuraminidase-treated SRBC. These observations suggest that complementary electrostatic charge on T cells and SRBC are among the forces facilitating formation of rosettes between these cells.