1983 Volume 32 Issue 9 Pages 947-959
Cell desensitization can be achieved in the presence of calcium, using subthreshold, suboptimal or supraoptimal concentrations of antigen. It should be noted that, in order to induce desensitization with suboptimal concentration of antigen, basophils will be preincubated with their specific antigen or anti-IgE at a concentration which gives 5 to l5% histamine release when the desensitizing antigen is given in a single step. When higher concentrations of antigen were used, paradoxical results were obtained, in that human basophils triggered by an optimal concentration of antigen after having been exposed to the same kind of desensitizing antigen in the presence of calcium released less histamine than those triggered by buffer after desensitization under the same conditions. It might be suggested that the antigen as a trigger made the cell membrane more stable against the mechanical or physical stimulation by manipulation of the cells for the experiment, thus halting the subsequent release of histamine. Incidentally, EDTA was not added to stop histamine release when all the experimentation was already finished. On the basis of this phenomenon, it might be suggested that the stabilization of the cell membrane against histamine release is a natural part of the cell desensitization process. At low temperature of 4℃, the desensitization rate decreased significantly and the cell desensitization could be induced under Ca^<2+>-free conditions. The experimental data which were obtained in this study might support, though do not prove, the possibility that desensitization may result from increased membrane stability due to increased membrane fiuidity.
