STUDIES ON J CHAIN AND BINDING-SITE FOR SECRETORY COMPONENT IN CIRCULATING HUMAN B CELLS .2. CYTOPLASM

  • 1 January 1976
    • journal article
    • research article
    • Vol. 25  (1) , 59-66
Abstract
About 0.3-1.1% of the lymphoid cells from peripheral blood of healthy adults contained cytoplasmic immunoglobulin (Ig). The class distribution of these B [bone marrow-derived] cells varied greatly among individuals, with a preponderate of the IgA (26-65%) or the IgG (15-66%) class. A remarkably high percentage of the Ig-containing cells were positive for cytoplasmic J chain regardless of the class (100% for IgM, 87-97% for IgA, 50-100% for IgD and 43-88% for IgG cells). This feature probably reflects the fact that the cells represent circulating blasts derived from the early expansion phase of B-cell clones. The antigenic determinants of the J chain were considerably masked in most IgA-containing cells, indicating that this subunit was correctly arranged in the IgA dimers at the cytoplasmic level in the manner demonstrated for intestinal IgA plasma cells.