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NASA NTRS · 20050000170

Staphylococcal enterotoxins bind H-2Db molecules on macrophages

Beharka, A. A.·Iandolo, J. J.·Chapes, S. K.·Spooner, B. S.
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Abstract

We screened a panel of monoclonal antibodies against selected macrophage cell surface molecules for their ability to inhibit enterotoxin binding to major histocompatibility complex class II-negative C2D (H-2b) macrophages. Two monoclonal antibodies, HB36 and TIB126, that are specific for the alpha 2 domain of major histocompatibility complex class I, blocked staphylococcal enterotoxins A and B (SEA and SEB, respectively) binding to C2D macrophages in a specific and concentration-dependent manner. Inhibitory activities were haplotype-specific in that SEA and SEB binding to H-2k or H-2d macrophages was not inhibited by either monoclonal antibody. HB36, but not TIB126, inhibited enterotoxin-induced secretion of cytokines by H-2b macrophages. Lastly, passive protection of D-galactosamine-sensitized C2D mice by injection with HB36 antibody prevented SEB-induced death. Therefore, SEA and SEB binding to the alpha 2 domain of the H-2Db molecule induces biological activity and has physiological consequences.

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Non-NASA CenterNASA Discipline Cell BiologyEnterotoxins/immunologyH-2 Antigens/chemistry/immunologyMacrophages/immunologyComparative StudyMolecular Sequence DataHistocompatibility Antigens Class II/geneticsSupport, Non-U.S. Gov'tMice, TransgenicAnimalsSupport, U.S. Gov't, P.H.SKineticsSupport, U.S. Gov't, Non-P.H.SAntibodies, Monoclonal/pharmacologyAmino Acid SequenceMiceStaphylococcus aureusProtein BindingInterleukin-6/biosynthesisTumor Necrosis Factor/biosynthesisMice, Inbred C57BL

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Beharka, A. A., Iandolo, J. J., Chapes, S. K., Spooner, B. S.. 1995-07-03. Staphylococcal enterotoxins bind H-2Db molecules on macrophages. https://ntrs.nasa.gov/citations/20050000170

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