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NASA NTRS · 20040142162

Complex high affinity interactions occur between MHCI and superantigens

Chapes, S. K.·Herpich, A. R.·Spooner, B. S.
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Abstract

Staphylococcal enterotoxins A and C1 (SEA or SEC1) bound to major histocompatibility-I (MHCI) molecules with high affinity (binding constants ranging from 1.1 microM to 79 nM). SEA and SEC1 directly bound MHCI molecules that had been captured by monoclonal antibodies specific for H-2Kk, H-2Dk, or both. In addition, MHCI-specific antibodies inhibited the binding of SEC1 to LM929 cells and SEA competitively inhibited SEC1 binding; indicating that the superantigens bound to MHCI on the cell surface. The affinity and number of superantigen binding sites differed depending on whether MHCI was expressed in the membrane of LM929 cells or whether it was captured. These data support the hypothesis that MHCI molecules can serve as superantigen receptors.

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NASA Discipline Cell BiologyNon-NASA CenterSuperantigens/metabolismAntigens, Bacterial/immunology/metabolismEnterotoxins/immunology/metabolismH-2 Antigens/immunology/metabolismSupport, U.S. Gov't, Non-P.H.SProtein BindingAntibodies, Monoclonal/immunologyAnimalsSupport, Non-U.S. Gov'tCell LineMice

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Chapes, S. K., Herpich, A. R., Spooner, B. S.. 1998-11-01. Complex high affinity interactions occur between MHCI and superantigens. https://ntrs.nasa.gov/citations/20040142162

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