Abstract: | Anti-DNA antibody responses by cultured circulating lymphocytes from SLE patients and by the tonsillar lymphoid cells of normal donors were detected and enumerated by a sensitive specific ELISA of culture supernatants, or by a hemolytic anti-DNA PFC assay. Although spontaneous IgM and IgG anti-DNA and anti-ssDNA responses were characteristic of SLE lymphocytes and spontaneous IgM anti-ssDNA responses were characteristic of tonsillar lymphocytes, the circulating lymphocytes of normal controls never produced anti-DNA antibodies spontaneously, and rarely after PWM stimulation. The anti-DNA antibody PFC response of tonsil lymphocytes correlated directly with the total number of immunoglobulin-producing cells measured by a reverse hemolytic PFC assay. Mixing experiments in which we employed cultures of comparable numbers of separately enriched autologous circulating and tonsillar B and T cells revealed that tonsillar tissue contained an enriched population of anti-DNA antibody precursor B cells and/or helper T cells. |