Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0153470 (Spleen)
 4,015 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The role of various subpopulations of antigen-presenting macrophages in the induction of T-lymphocyte subpopulations has been difficult to study in the past. We have used an in vitro system of bone marrow cell culture both to induce T-effector (TDH) and T-suppressor (Ts) cells active in delayed-type hypersensitivity. Bone marrow-derived macrophages (BM-MA) grown in Teflon bag cultures were allowed to attach to culture dishes and were pulse-labeled with 2,4-dinitrobenzene sulfonate (DNBSO3). Spleen cell lymphocytes from nonsensitized BALB/c mice were cocultured with antigen-pulsed or control BM-MA for 3 days. The lymphocytes were harvested, and injected iv into BALB/c mice which were challenged within 1 hr after injection by painting the right ear with 2,4-dinitrofluorobenzene (DNFB, effector test) or sensitized with DNFB on 2 days following iv injection of the cells and challenged 5 days later (suppressor test). Ear swelling was measured 24 hr later to assess the effector or suppressor function of the in vitro educated lymphocytes. BM-MA grown for 5 days (BM-MA 5) in L-cell conditioned medium induced only TDH cells (Thy 1+, Lyt 1+2-) whereas BM-MA grown for 10 days in conditioned medium induced only Ts cells (Thy 1+, Lyt 1-2+). In both cases, induced TDH and Ts cells were antigen specific. Functionally, induced Ts cells suppressed the afferent limb of the delayed response. When DNP-BM-MA 5 and DNP-BM-MA 10 were used to induce TDH or Ts cells in vivo by subcutaneous or intravenous injection respectively, only BM-MA 5 were able to sensitize recipient mice. Both 5- and 10-day macrophage populations induced Ts cells in vivo. Functionally, these Ts cells appeared to act on the efferent limb of the delayed reaction. We conclude that different populations of antigen-presenting macrophages can preferentially induce TDH or Ts cells, perhaps depending on antigen presentation in association with class II antigens or on the functional state of the antigen-presenting cell.
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PMID:Selective induction of delayed hypersensitivity T-effector and T-suppressor lymphocytes in vitro by haptenized bone marrow-derived macrophages. 623 31

Hapten specific lymphocyte proliferative assay was used to measure systemic immunization induced by epicutaneously applied hapten, instead of the assay measured by ear swelling or footpad swelling. DNFB was painted on the shaved back of C 57 BL/6 on two consecutive days and 4 days later. DNFB sensitized lymph node cells (LNC) were obtained from the regional lymph nodes. Spleen cells were pulsed with an antigen after irradiation and used as antigen presenting cells (APC). Various numbers of LNC were cultured with various number of APC to determine the highest lymphocyte proliferation. This was observed when 2 x 10(5) cells/well APC were cultured 4 x 10(5) cells/well LNC. In next step, this assay was used to investigate whether contact dermatitis is a required subject or not to sensitize. FB could not induce contact dermatitis on the painted region not only clinically but also histologically. FB, however, was able to induce hapten specific lymphocyte proliferation. This fact demonstrates that contact dermatitis is not always necessary in sensitization through epicutaneous application of hapten.
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PMID:[Whether allergic contact dermatitis is necessary to induce systemic immunization by applied hapten]. 921 68