Increased regulatory T cells and impaired functions of circulating CD8 T lymphocytes is associated with viral persistence in Hepatitis B virus‐positive newborns. Issue 8 (14th February 2013)

• Record Type: Journal Article
• Authors: Shrivastava, S.; TrehanPati, N.; Patra, S.; Kottilil, S.; Pande, C.; Trivedi, S. S.; Sarin, S. K.
• Is Part Of: Journal of viral hepatitis. Volume 20:Issue 8(2013)
• Page Start: 582
• Page End: 591
• Publication Date: 2013-02-14
• Subjects: Hepatitis, Viral -- Periodicals; Hepatitis, Viral, Animal; Hepatitis, Viral, Human; 616.3623
• DOI: 10.1111/jvh.12078
• Languages: English
• ISSNs: 1352-0504

Abstract

<abstract abstract-type="main" id="jvh12078-abs-0001"> <title>Summary</title> <p>Hepatitis B Virus (HBV) infection in infancy or early childhood leads to high rate of persistent infection (25–90%). The immunological basis of high rate of viral persistence in vertically acquired HBV infections is not completely understood. CD8 T cells play a pivotal role in clearing the Hepatitis B virus infection in adults. Herein, we sought to delineate the role of T cells in viral persistence in HBsAg+ve newborns<bold>.</bold> At birth peripheral and cord blood of HBsAg+ve (<italic>N</italic> = 12), HBsAg‐ve (<italic>N</italic> = 10) and healthy newborns (HC:<italic> N</italic> = 15) were evaluated for T‐cell frequency and functionality by flow cytometry. No significant differences were observed in the frequency of CD8 and CD4 T cells in all the three groups. However, significantly higher frequency of FoxP3 expressing regulatory T cells were observed in HBsAg+ve (63.79%) compared with HBsAg‐ve (28.12%) and HC (11.06%) (<italic>P</italic> < 0.05). Moreover, HBsAg+ve newborns showed functional defect in CD8 T cells by decreased IFN‐γ production and lower CD107A expression (cytotoxic capacity) compared with HBsAg‐ve and HC, which positively correlated with decreased TCRζ‐chain expression CD8 T cells (<italic>r</italic><sup>2</sup> > 0.93, <italic>P</italic> < 0.05). Despite equal frequency of CD8 T cells in all the three groups, CD8 T cells in HBsAg+ve newborns are dysfunctional. An expansion of regulatory T cells and impaired TCR signalling may represent the immune tolerant state of the adaptive immune system in response to chronic HBV infection.</p> </abstract>