title: Evidence for an interaction between leptin, T cell costimulatory antigens CD28, CTLA-4 and CD26 (dipeptidyl peptidase IV) in BCG-induced immune responses of leptin- and leptin receptor-deficient mice.
abstract: We assessed changes of the enzyme dipeptidyl peptidase IV (DPP IV, CD26) in the context of leptin or leptin receptor deficiency. C57BL/6 mice, Leptin-deficient mice (ob/ob mice, B6.V-Lep<ob>) and Leptin-receptor-deficient mice (db/db mice, B6.Cg-m+/+Lepr) were infected with B. Calmette-Guerin (BCG) and sacrificed three days later. DPP IV activity in serum was higher in ob/ob mice and in db/db mice than in wild-type mice. The expression of DPP IV/CD26 on splenocytes was higher in ob/ob mice than in wild-type animals, and lower in db/db mice, and decreased upon stimulation with BCG in ob/ob mice only. Several T cell antigens including CTLA-4 were expressed aberrantly in ob/ob and in db/db mice. Our observations provide evidence for a relationship between DPP IV and leptin.
authors.affiliation: Department of Internal Medicine, Division of Psychosomatic Medicine and Psychotherapy, Charité University Hospital, Schumannstrasse 20/21, D-10117 Berlin, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Rüter
authors.forename: Torsten
authors.initials: T
authors.lastname: Hoffmann
authors.forename: Hans-Ulrich
authors.initials: HU
authors.lastname: Demuth
authors.forename: Petra
authors.initials: P
authors.lastname: Moschansky
authors.forename: Burghard F
authors.initials: BF
authors.lastname: Klapp
authors.forename: Martin
authors.initials: M
authors.lastname: Hildebrandt
mesh_terms: D000818:Animals; D015703:Antigens, CD; D000943:Antigens, Differentiation / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D001500:BCG Vaccine / Q000276:immunology; D018106:CD28 Antigens / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D060908:CTLA-4 Antigen; D018819:Dipeptidyl Peptidase 4 / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D005260:Female; D015971:Gene Expression Regulation, Enzymologic; D020738:Leptin / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009163:Mycobacterium bovis / Q000276:immunology* / Q000378:metabolism; D011956:Receptors, Cell Surface / Q000235:genetics / Q000276:immunology* / Q000378:metabolism; D054411:Receptors, Leptin
chemical_list: D015703:Antigens, CD; D000943:Antigens, Differentiation; D001500:BCG Vaccine; D018106:CD28 Antigens; D060908:CTLA-4 Antigen; C556707:Ctla4 protein, mouse; D020738:Leptin; D011956:Receptors, Cell Surface; D054411:Receptors, Leptin; C515447:leptin receptor, mouse; D018819:Dipeptidyl Peptidase 4