Enhancement of Antibody Production by Anti-Delta Antibodies

摘要

The abilities of four stimuli to activate B lymphocytes in vivo and induce B cells to proliferate and differentiate into antibody secreting cells were studied. A goat antibody to mouse IgD (GaM Delta) stimulates T independent increases in B cell DNA synthesis and T dependent increases in spleen cell number and IgG1 secretion. Serum IgG1 levels increase to 50-100 times control levels, and 5-15% of the Ig secreted is goat IgG specific. Autoantibody production is not detectable. Injection of GaM Delta plus a toxin - normal goat IgG conjugate stimulates rapid production of large quantities of IgG1 anti-toxin antibody, and facilitiates the generation of anti-toxin secreting monoclonal antibodies. A second agent, 8-mercaptoguanosine (8MG) stimulates neither B cell proliferation nor antibody production by itself, but enhances antigen specific antibody responses, particularly IgG2 responses. A third agent, lipid A, stimulates B cell proliferation but fails in vivo to increase serum IgM or IgG levels. Combinations of GaM Delta, lipid A, and 8MG synergistically induce large increases in spleen cell number and polyclonal IgG2 secretion but fail to stimulate a polyclonal IgG1 response or a specific anti-goat IgG response.