Distinct patterns of granulocyte luminol-dependent chemiluminescence response to lectins WGA and RCA-I

Abstract

THe chemiluminescence response was measured in human polymorphonuclear leukocytes (PMNLs) after stimulation with different concentrations of the lectins Triticum vulgaris agglutinin (wheat germ agglutinin, WGA) and Ricinus communis agglutinin I (RCA-I). The two lectins achieved distinct patterns of chemiluminescence; RCA-I evoked a dose-dependent response (0-15 micrograms/ml) with respect to the initial rate of light emission, but the peak value was reached after different lengths of time. A maximum response was obtained after about 25 min with a concentration of 2-4 micrograms/ml. By contrast, WGA caused a bimodal reaction after stimulus addition. In this case the first peak occurred after 15-20 min, and the second peak after around 60 min with maximum effect for 0.5 and 0.25-0.50 micrograms/ml WGA, respectively. The PMNL response is discussed in relation to the regulation of the production of oxygen metabolites and in relation to the pathophysiologic consequences of lectin-mediated activation of phagocytic cells in intestinal epithelium.