Pollen-induced chemiluminescence: inhibition by serum from allergic individuals

The interaction between pollen grains, polymorphonuclear leukocytes (PMNs) and serum results in the formation of "pollen rosettes" and the production of chemiluminescence (CL). Significantly more CL is produced by cells exposed ot pollen and sera from nonallergic individuals compared with sera from allergic individuals. The source of the PMNs, however, has no effect on the CL produced, When IgG is isolated from the sera of allergic individuals and added to the test system, a large CL response is seen that is inhibited by the IgG-depleted fraction. No similar inhibition is produced by the IgG-depleted fraction of sera from nonallergic individuals. The inhibitor of CL in sera from allergic individuals appears to be IgE, since its removal leads to an enhanced CL response. These results suggest that competition for a limited number of binding sites on pollen grains exists between pollen specific IgG and IgE antibodies in serum from allergic patients.