Abstract: | The in vitro production of anti-double stranded DNA antibodies (anti-DNA) by peripheral blood mononuclear cells (PBMC) was investigated in 19 patients with systemic lupus erythematosus (SLE) and in 12 normal individuals, using a micro solid phase enzyme immunoassay. PBMC from SLE patients spontaneously produced anti-DNA with a higher frequency (16 of 19) than did PBMC of controls (three of 12). In addition SLE patients produced predominantly IgG antibodies. PWM and DNA enhanced anti-DNA synthesis is spontaneously low and non-producers, but acted as inhibitors in spontaneously high producers. The partial removal of T cells decreased or abolished anti-DNA synthesis in four of nine SLE patients. In contrast the B cell enriched fractions of five of nine SLE and five of seven normal patients produced the same or higher anti-DNA levels than did the corresponding unseparated PBMC. These results suggest evidence for autoreactive B cells in SLE as well as in normals, and therefore the combination of these autoreactive B cells with helper and/or suppressor T cell disorders could lead to the over production of anti-DNA seen in different patients with SLE. |