Abstract: | Wistar-Furth (W-F) rats were given 10(9) syngeneic spleen cells, suspended in Hanks' balanced salt solution (HBSS), intravenously on Day 0 to investigate the mechanisms involved in antigen-specific suppression of collagen arthritis. These cells were pooled from W-F donors which had been injected iv on Days -21, -14, and -7 with rat red blood cells (RBC) coupled with glutaraldehyde to either native chick type II collagen, denatured type II collagen, or native type I collagen. All recipients were immunized with an emulsion of native type II collagen in incomplete Freund's adjuvant on Day 1 to induce collagen arthritis. There was a decreased incidence of arthritis, by clinical and radiographic assessments, in rats receiving spleen cells from donors previously administered native type II collagen-coupled RBC compared to those given spleen cells obtained from donors treated with denatured type II or native type I collagen-coupled RBC [18 of 30 (60%) arthritic vs 20 of 20 (100%) and 19 of 20 (95%) arthritic, for the three groups, respectively, P less than 0.01 for both comparisons]. The incidence of arthritis in 35 rats administered HBSS iv 1 day prior to immunization (83%) and 10 immunized rats given no iv injections (100%) was also significantly higher (P less than 0.05) than the incidence in the antigen-relevant experimental group. Hemagglutinating antibody titers and delayed-type hypersensitivity (DTH) to collagen were lower in the recipients of cells from donors administered native type II collagen-coupled RBC, whereas IgG antibody titers to collagen were unaltered. These results demonstrate that passively transferred spleen cells can attenuate collagen arthritis and sensitization in an antigen-specific manner. |