| mmune complexes (IC) composed of antibody and antigen are potent regulators of the humoral response capable of augmenting or inhibiting antibody production. A critical factor in determining the type of response elicited depends upon the accessory cell which first presents IC. Initial studies demonstrated that IC-pulsed macrophages inhibited the differentiation of murine B cells into IgM secreting plasma cells. Since antigen-specific IgM responses were never totally inhibited, it was theorized that splenic B cells were heterogeneous in their sensitivity to IC. Following fractionation on Percoll density gradients, resting B cells incubated with 10 ;It was theorized that the IC-mediated decrease in IgM antibody responses was not due to a block in differentiation, but was a preliminary event in immunoglobulin class switching which required critical T lymphocyte cytokines such as ;These findings support the concept that... |
