Induction of anti-ssDNA antibodies in normal and preautoimmune mice in vivo.

Splenic lymphoid cells of normal and preautoimmune mice escape normal regulatory mechanisms in vitro and spontaneously synthesize anti-ssDNA antibody in the absence of any exogenous antigen. In addition, both the cultured cells and their cell-free supernatants were capable of inducing specific anti-ssDNA responses in vivo upon their injection into syngeneic recipients. The response was host-derived, required the participation of B and T cells, and was not due to polyclonal activation. The immunogen responsible for this response appeared to be membrane-associated, was found predominantly on cultured T cells, and was sensitive to DNase and proteolysis.