Proceedings of the National Academy of Sciences of the United States of America
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Proc. Natl. Acad. Sci. U.S.A. · Nov 1979
Induction of calcium flux across the rat mast cell membrane by bridging IgE receptors.
Rabbit antibody against IgE receptors or its F(ab')2 fragments induced an increase of 45Ca uptake into normal mast cells, and this process was accompanied by histamine release. Evidence was obtained that a substantial portion of 45Ca uptake was due to movement of calcium across the cell membrane. ⋯ However, bridging of receptor-bound Fab' fragments by antirabbit IgG or bridging of receptor-bound IgE by anti-IgE induced an increase in 45Ca uptake. The results collectively indicate that crosslinking IgE receptors increases the membrane permeability of the mast cells toward calcium.
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Proc. Natl. Acad. Sci. U.S.A. · Nov 1979
Crossreactive mixed lymphocyte reaction determinants recognized by cloned alloreactive T cells.
We have isolated clones of alloreactive T cells by soft agar cloning of primed responder cells contained in serially restimulated, mixed lymphocyte cultures. These clones recognize unique mixed lymphocyte reaction (MLR) stimulating determinants present on (C57B/6 X A/J)F1 (B6A) spleen cells. ⋯ Using such clones of alloreactive T cells, we have identified and are attempting to define crossreactive MLR stimulating determinants exhibited by a panel of stimulator cells. Recognition by certain clones of a shared MLR determinant(s) on B6A and DBA/2 and of the lack of this determinant(s) on B6 stimulator cells questions current concepts concerning the nature of MLR stimulating determinants and T cell recognition of alloantigens.