DIFFERENTIATION OF LYMPHOCYTES-B IN SHEEP .1. PHENOTYPIC ANALYSIS OF ILEAL PEYERS PATCH CELLS AND THE DEMONSTRATION OF A PRECURSOR POPULATION FOR SIG+ CELLS IN THE ILEAL PEYERS PATCHES

  • 1 January 1984
    • journal article
    • research article
    • Vol. 53  (3) , 515-523
Abstract
The ileal Peyer''s patches(IPP) of sheep may be a primary lymphoid organ for B cells since they have several important features in common with the bursa of Fabricius of chickens. The surface phenotype of IPP cells was examined. Approximately 90-95% of IPP cells are low sIgM+, i.e., they have surface IgM, but in much smaller amounts than peripheral B cells, which are high sIgM+. IPP cells with sIgG or sIgA are very rare. On exposure to a tumor promotor, phorbol myristate acetate (PMA), in vitro, low sIgM+ cells differentiated into high sIgM+ cells. The amount of Ia-like antigens on the surface also increased after PMA treatment. Approximately 5% of IPP cells bore no identifiable markers. However, these cells could also be induced into high sIgM+ cells on exposure to PMA; this may indicate the presence of precursors of sIgM+ cells within the IPP. While PNA (peanut agglutinin) binds strongly to the vast majority of IPP cells, it binds very little if at all, to B cells obtained from the periphery, unless they have been treated with neuraminidase; this suggests that cells in the B lineage retain their PNA receptors, but that these become masked by sialic acid on mature B cells.