Changes in the protein pattern of murine B cells after mitogenic stimulation

The technique of two‐dimensional gel electrophoresis has been applied to study the changes in protein patterns occurring in murine B lymphocytes after activation with the synergistic B cell mitogens lipopolysaccharide and dextran sulfate. Whole cell lysates from [³⁵S]methionine‐labeled mitogen‐activated B cells were analyzed and radiofluorographs of the gels compared. We found that a large number of proteins appear and disappear during the 5‐day activation period (74/206 spots of a nonimmunoglobulin region of the gel). The B cell pattern (in the nonimmunoglobulin region) was also compared with that of mitogen‐activated T cells. We identified 19 T cell‐specific and 29 B cell‐specific proteins, the remaining 1000 or so proteins being common.