Changes in intracellular calcium free and calcium stored balance in children granulocytes after stimulation. Preliminary results

Abstract

In human granulocytes calcium fluxes are crucial for effective production of oxygen intermediates in signal transduction pathways originating from chemoattractant receptors. The evidence rise that factors stimulating oxidative burst independently from calcium signaling pathways may exert modulatory effects on intracellular calcium free level. The aim of our study was to examine the impact of well known receptor (fMLP) and non-receptor (PMA) related oxidative burst inducers on calcium kinetics in children suffering from recurrent infections. Granulocytes were withdrawn from group of: healthy children and children suffering from recurrent infections. Simultaneous calcium free and calcium stored measurement was performed by flow cytometer. PMA-induced, deep and long lasting (over 420 sec.), decline in calcium free level was more evident in children suffering from recurrent infections during first 240 sec. Also in this group, prolongation of recovery was visible after stimulation with fMLP. In conclusion we suggest that: 1. calcium kinetics is shifted in children suffering from recurrent infections, 2. PMA interfere with intracellular calcium free level.