Efficiency of antigen presentation to T cell clones by (B cell × B cell lymphoma) hybridomas correlates quantitatively with cell surface Ia antigen expression

摘要

AbstractA series of B cell hybridomas was used as a model system to assess quantitatively the role of Ia molecules in antigen presentation to allo‐ or soluble antigen‐reactive T cell clones. These hybrid cell lines were established by fusion between the HGPRT−BALB/c B cell lymphoma M12.4.1 and LPS‐stimulated spleen blasts from B10.BR (H‐2k) mice. Quantitative cellular absorption of appropriate anti‐Ia monoclonal antibodies and flow cytofluorometric analyses revealed that the B cell hybridomas examined herein expressed constitutively a number of surface I‐Akor I‐Ekmolecules that varied in an order of magnitude of 1 to 5. Such quantitative differences could be correlated precisely with (a) the capacity of B cell hybridomas to activate T cell clones to proliferate and/or to produce interleukin 2 in response to Eβkallodeterminant or to poly(Glu60Ala30Tyr10) presented in the context of I‐Akrestriction element, and (b) the amount of monoclonal anti‐I‐Akantibody required to inhibit antigen presentation to T cell clones. The possible implications of these data are discussed in the context of current models of regulation of Ia antigen expression by an