title: C1-esterase inhibitor blocks T lymphocyte proliferation and cytotoxic T lymphocyte generation in vitro.
abstract: We have previously shown that activated C1s complement and activated T cells cleave beta2-microglobulin (beta2m) in vitro leading to the formation of desLys58 beta2m. This process can specifically be inhibited by C1-esterase inhibitor (C1-inh). Furthermore we showed that exogenously added desLys58 beta2m in nanomolar amounts to a one-way allogenic mixed lymphocyte culture (MLC) increased the endogenous production of IL-2 and the generation of allo-specific cytotoxic T lymphocytes. C1-inh was purified from fresh human plasma and added to human or murine MLC and mitogen-stimulated lymphocyte cultures grown in the presence of complement-inactivated serum. Read-outs were cell proliferation, lymphokine production and development of T cell-mediated cytotoxicity. We found that addition of C1-inh to MLC and mitogen-exposed murine and human lymphocyte cultures inhibited proliferation, the development of allospecific cytotoxic activity, and changed the endogenous production of IL-2, IL-4, IL-10, IL-12 and IFN-gamma. These data clearly demonstrate a regulatory function of C1-inh on T cell-mediated immune functions.
authors.affiliation: Department of Medical Anatomy, The Panum Institute, University of Copenhagen, Denmark.
authors.forename: M H
authors.initials: MH
authors.lastname: Nissen
authors.forename: S
authors.initials: S
authors.lastname: Bregenholt
authors.forename: J A
authors.initials: JA
authors.lastname: Nording
authors.forename: M H
authors.initials: MH
authors.lastname: Claesson
mesh_terms: D000818:Animals; D002478:Cells, Cultured; D003174:Complement C1 Inactivator Proteins / Q000494:pharmacology*; D003173:Complement C1s / Q000378:metabolism*; D006801:Humans; D008213:Lymphocyte Activation / Q000187:drug effects*; D007959:Lymphocyte Culture Test, Mixed; D051379:Mice; D008807:Mice, Inbred BALB C; D008810:Mice, Inbred C57BL; D011480:Protease Inhibitors / Q000494:pharmacology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology*
chemical_list: D003174:Complement C1 Inactivator Proteins; D011480:Protease Inhibitors; D003173:Complement C1s