Changes in HLA-DR Expression on Monocytes and Lymphocytes in Neonatal Sepsis

Abstract

© 2018, Springer Science+Business Media, LLC, part of Springer Nature. HLA-DR is a key marker of leukocyte activation, which suppression determines the effectiveness of immune response and prognosis in neonatal sepsis (NS). The aim of this study was to evaluate the HLA-DR expression on lymphocytes and monocytes in the peripheral blood of neonates with sepsis. The study involved 21 neonates with sepsis and 10 healthy neonates born during the study period. Bacteremia was detected in five cases (24%). The most frequent pathogens found were Klebsiella pneumoniae (n = 2) and Staphylococcus aureus (n = 2) followed by Streptococcus agalactae (n = 1). NS was associated with pneumonia (n = 17), meningitis (n = 3), and necrotizing enterocolitis (n = 1). The onset of NS was accompanied with high blood monocyte activity which ranged from 96 to 100%. Blood CD3+ lymphocyte population and CD4+ and CD8+ lymphocyte subset levels were decreased, with their median values being 1.7, 2.2, and 2.4 times lower than those in the control group, respectively (р = 0.005, р = 0.0002, р = 0.003). The HLA-DR expression on CD3+ lymphocytes, as well as on CD4+ and CD8+ lymphocyte subsets, was extremely low ranging from 0.1 to 7% both in the onset of the disease and in a week after admission to a hospital. Absolute counts of activated CD4+ and CD8+ lymphocyte subsets were significantly lower on the disease first days as compared to the control group (р = 0.02 and р = 0.003, respectively). These results demonstrate adaptive immunity to be non-effective in neonates with sepsis. Low expression of HLA-DR on CD3 lymphocytes as well as on CD4 and CD8 lymphocyte subsets is a reason for immunostimulating therapy.