The ability of peripheral blood lymphocytes (PBL), T cells, B cells, and monocytes from normal volunteers as well as from patients with SLE, chronic lymphocytic leukemia (CLL), and Sezary syndrome to function as effector cells in a lymphocyte-dependent antibody-mediated cytolytic (LDAMC) process, using DNA-anti-DNA-coated sheep red blood cells as targets, was studied. Both normal peripheral blood B cells and monocytes functioned well in this assay at an effector to target ratio of 10:1 using as little as a 10-5 dilution of antibody. In contrast, peripheral blood T cells as well as cells from patients with CLL and Sezary syndrome were ineffective. PBL derived from patients with inactive SLE were similar to normal PBL in this assay. However, PBL from patients with active SLE had little effector activity at low effector to target cell ratios. At high effector to target cell ratios this decreased efficiency was less marked. Unlike human PBL, spleen cells from New Zealand and BALB/c mice functioned only at effector to target cell ratios of > 50:1. Moreover, with age, a significant decrease in the ability of New Zealand, but not BALB/c, spleen cells to function in this assay was noted. As with other LDAMC systems, the reaction was mediated by IgG antibody and was inhibited by aggregated human γ-globulin. Although LDAMC appears depressed in both patients and mice with active SLE, we suggest the possibility that LDAMC of immune complex-coated cells/tissue may be an additional mediator of tissue injury.
ASJC Scopus subject areas
- Immunology and Allergy
- Pathology and Forensic Medicine