NK and CTL recognition of a single chain H-2Dd molecule: distinct sites of H-2Dd interact with NK and TCR

D H Chung1, J Dorfman, D Plaksin

  • 1Molecular Biology and Lymphocyte Biology Sections, Laboratory of Immunology, National Institute of Allergy and Infectious Diseases, Bethesda, MD 20892, USA.

We generated transgenic mice expressing a single-chain beta2-microglobulin (beta2m)-H-2Dd. The cell-surface beta2m-H-2Dd molecule was expressed on a beta2m-deficient background and reacted with appropriate mAbs. It was of the expected m.w. and directed the normal development of CD8+ T cells in the thymus of a broad TCR repertoire. It also presented both exogenously provided and endogenous peptide Ags to effector CD8+ T cells. In tests of NK cell education and function, it failed to reveal any interaction with NK cells, suggesting that the site of the interaction of NK receptors with H-2Dd was disrupted. Thus, the sites of TCR and NK receptor interaction with H-2Dd are distinct, an observation consistent with independent modes of TCR and NK receptor evolution and function.

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