[REDUCED RESPONSE OF NATURAL KILLER LYMPHOCYTES TO TOLL-LIKE RECEPTOR 3 STIMULATION IN CHILDREN WITH RECURRENT INFECTIONS.]

Abstract

In this study, we examined the activation of natural killer(NK)-lymphocytes mediated by Toll-like receptor 3(TLR3), in the group of children with recurrent infections and the group of children with invasive bacterial infections. We examined level of CD69 (marker, of activation) expression on NK - lymphocytes after incubation with TLR3 ligand. There was a significant decrease in the level of an activation marker - 36,3±4,4% in the group of children with recurrent infections, compared with a control group of healthy children (56,5±4,9%) and the group of children with invasive bacterial infections (55,9±4,4%). Also, decreased was an activation potential of NK-lymphocytes - 24,9±L4,5% which was calculated as the difference between the percentage of CD69+ NK - lymphocytes after incubation and spontaneous value (without the addition of activator). There were no correlations between markers of TLR3 mediated activation of NK-cells and the age. Thus, the ability to activate NK - lymphocyte mediated by TLR3, independent of age and reduced in the group of children with recurrent infections. Reduced activation of NK-lymphocytes may contribute to increased susceptibility to viral infections and bacterial complications.