MULTIPLE HEAVY-CHAIN ISOTYPES ON THE MEMBRANE OF THE SMALL LYMPHOCYTES-B IN HUMAN-BLOOD

  • 1 January 1981
    • journal article
    • research article
    • Vol. 43  (1) , 149-156
Abstract
Small lymphocytes from adult human blood were examined for the presence of membrane-associated .alpha., .gamma., .delta. and .mu. Ig isotypes by means of a direct immunofluorescence technique. Since less than 10% of the small lymphocytes in blood are B cells as defined by positive reactivity with an anti-Fab conjugate, experiments were performed on a T cell-depleted fraction in which about 80% of the small lymphocytes were B cells. With the 2-wavelength immunofluorescence method, all of the double-isotype combinations were found. The percentage of cells bearing more than 2 isotypes was deduced. The .delta..mu. and the .alpha..delta..mu. combinations were the most common, as previously found on tonsillar lymphocytes. In contrast with the tonsils, no lymphocytes bearing only .delta. were observed; the proportions of .alpha..gamma. and .alpha..gamma..mu.-bearing lymphocytes were very small. The presence of lymphocytes bearing 4 isotypes could practically be excluded.