VARIATION OF NATURAL KILLER CELLS PHENOTYPE AND ACTIVITY IN VARIOUS STAGES OF HEPATITIS C VIRUS INFECTION IN EGYPTIAN PATIENTS

Abd El-Kader, Asmaa; Salama, Hosni; Zekri, Abd EL-Rahman; Marzouk, Hanan Abd EL-Halim; El Deeb, Somaya

doi:10.12816/0009346

VARIATION OF NATURAL KILLER CELLS PHENOTYPE AND ACTIVITY IN VARIOUS STAGES OF HEPATITIS C VIRUS INFECTION IN EGYPTIAN PATIENTS

Document Type : Original Research Papers

Authors

¹ Department of Zoology, Faculty of Science, Cairo University, Giza, Egypt

² Department of Digestive System and Liver Diseases, Faculty of Medicine, Cairo University, Cairo, Egypt

³ Department of Cancer Biology, Natural Cancer Institute, Cairo University, Cairo, Egypt

10.12816/0009346

Abstract

During the early phases of a hepatitis C virus (HCV) infection, natural killer (NK) cell activation appears to be critical to the innate (non-specific) immune responses that have the potential of clearing the infection. Impaired activity of NK cells has been proposed as a mechanism contributing to viral persistence and chronic infection in HCV infection. We aimed to assess the impact of HCV infections on NK cells regarding frequency, and subset distribution. Peripheral blood (PB) NK cells population of individuals were divided into the following groups: healthy controls (HC) and patients at different stages of HCV: 37 chronic HCV (CHC), 28 cirrhotic HCV and 24 with hepatocellular carcinoma (HCC). The phenotype and frequency of NK cells were characterized by flow cytometry in the different stages in comparison to HC. The potential associations between the frequency of NK cell subsets and the activity of serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST), as indicators of liver function, were analyzed. The correlation between the phenotype of NK subsets and the various stages of HCV infection was assayed. Number of total NK was significantly reduced and a striking shift in NK subsets, with a marked decrease in the CD56^dim cell fraction compared to CD56^bright cells was identified. Interestingly, we found that the number of NK cells (CD56⁺) bearing the inhibitory receptor CD158b (KIR) increased in HCV patients at various stages, whereas the percentage of NK cells expressing activating receptors CD314⁺(NKG2D), CD161⁺ were significantly reduced, as compared to HC. These results indicated alteration of NK cell subsets in frequency and marker expression in different stages of HCV patients compared to HC as inhibitory NK cells frequency increased, while activated NK cells were reduced, which might be associated with impaired innate immune responses and virus persistence.

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