The Capping of Surface Immunoglobulin on Mouse Myeloma Cells

[摘要] Immunoglobulin determinants have been found on the surface of mouse plasmacytoma cells producing molecules of various classes and types (1–4). In some cases the surface immunoglobulins have been shown to share the antibody activity of the immunoglobulin secreted by these cells (5, 6). However, it is not completely clear whether the immunoglobulin determinants detected on the surface of the myeloma cell are comparable to surface immunoglobulins found on the surface of B lymphocytes or are molecules in the act of being secreted. In studies on the P3 (MOPC 21) mouse myeloma cells, Knopf (7) has shown that surface immunoglobulin determinants turn over much more slowly than secreted immunoglobulin. However it has been difficult to demonstrate efficient capping of plasma cells in general, and of mouse myeloma cells in particular. In order to examine this further, we have studied the surface immunofluorescence of two established mouse plasmacytoma cell lines and shown that capping does occur if the secreted immunoglobulin is first removed from the cell.

[学科分类] 生物科学（综合）