Presentation of antigen by mixed isotype class II molecules in normal H-2d mice.

• Published in: Journal of Experimental Medicine
• Main Authors: Ruberti, G, Sellins, K S, Hill, C M, Germain, R N, Fathman, C G, Livingstone, A
• Format: Article in Journal/Newspaper
• Language: English
• Published: Rockefeller University Press 1992
• Subjects: Sperm whale
• Online Access: http://dx.doi.org/10.1084/jem.175.1.157; https://rupress.org/jem/article-pdf/175/1/157/1672764/157.pdf

A panel of DBA/2 T cell hybridomas specific for the sperm whale myoglobin epitope 110-121 was found to recognize antigen presented by the mixed isotype class II molecule E alpha dA beta d. The response was blocked by monoclonal antibodies specific for E alpha and A beta d chains; in addition, the hybridomas responded to antigen presented by L cells expressing E alpha A beta d molecules, and made no response with L cells expressing I-Ad or I-Ed molecules. Two more groups of hybridomas isolated from DBA/2 and B10.D2 mice immunized with myoglobin also recognized peptide 110-121 presented by E alpha d A beta d. Thus, although it is expressed at biochemically undetectable levels on spleen cells, the E alpha d A beta d molecule is an important presenting element in normal H-2d mice making a conventional immune response to a protein antigen. These results suggest that high levels of class II expression are not a prerequisite for T cell activation.