title: Selective immunomodulatory activity of SK&F 106615, a macrophage-targeting antiarthritic compound, on antibody and cellular responses in rats and mice.
abstract: The azaspiranes are novel immunomodulators which are effective in a variety of animal models of autoimmune disease and transplantation. The compounds appear to target macrophages and alter their functional activity. One of these compounds, SK&F 106615 (N,N-diethyl-8,8-dipropyl-2-azaspiro[4.5]decane-2-propanamine++ + dihydrochloride), is now in phase II clinical trials for rheumatoid arthritis. As many drugs/compounds effective in autoimmune disease and transplantation are overtly immunosuppressive, we designed studies to show that SK&F 106615 has selective immunomodulatory effects and that it does not perform in a manner characteristic of classical immunosuppressive agents on immune function. SK&F 106615 inhibited mouse and rat spleen cell and rat peripheral blood mononuclear cell proliferation in vitro with an IC50 of 500 nM. In vivo, treatment of C57BL/6 mice (15 mg/kg/day, i.p.) or rats (20 mg/kg/day, p.o.) for 2 weeks had no effects on specific antibody synthesis to ovalbumin (OVA) compared to rapamycin (RAP) which completely suppressed the antibody response. Compared to cyclosporin A (CsA), FK 506 and RAP which suppressed the antibody (plaque forming) response to particulate (sheep red blood cells) antigen in a dose responsive manner, SK&F 106615 administered at a dose of 50 mg/kg was inactive. There was an inhibition of the proliferative response of lymph node cells from treated mice and rats to mitogen and antigen in ex vivo assays. SK&F 106615, but not RAP, induced cells in the spleens of mice that could inhibit normal spleen cell proliferation in a co-culture assay. Thus, a selective immunomodulatory effect can be shown for SK&F 106615 in the absence of generalized immunosuppression.
authors.affiliation: Department of Cellular Biochemistry, SmithKline Beecham Pharmaceuticals, King of Prussia, PA 19406-0939, USA.
authors.forename: A M
authors.initials: AM
authors.lastname: Badger
authors.forename: T M
authors.initials: TM
authors.lastname: Newman-Tarr
authors.forename: J L
authors.initials: JL
authors.lastname: Satterfield
mesh_terms: D000276:Adjuvants, Immunologic / Q000494:pharmacology*; D000818:Animals; D000894:Anti-Inflammatory Agents, Non-Steroidal / Q000494:pharmacology*; D000917:Antibody Formation / Q000187:drug effects; D018501:Antirheumatic Agents / Q000494:pharmacology*; D002478:Cells, Cultured; D005260:Female; D007963:Leukocytes, Mononuclear / Q000187:drug effects / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects; D008264:Macrophages / Q000187:drug effects; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010047:Ovalbumin / Q000494:pharmacology; D051381:Rats; D011917:Rats, Inbred Lew; D013141:Spiro Compounds / Q000494:pharmacology*; D013154:Spleen / Q000166:cytology / Q000187:drug effects / Q000276:immunology
chemical_list: D000276:Adjuvants, Immunologic; D000894:Anti-Inflammatory Agents, Non-Steroidal; D018501:Antirheumatic Agents; D013141:Spiro Compounds; C099015:azaspirane; D010047:Ovalbumin