Sex Differences in Spontaneous Degranulation Activity of Intrahepatic Natural Killer Cells during Chronic Hepatitis B: Association with Estradiol Levels

Abstract

Major sex differences are observed in the prevalence, intensity, and severity of hepatitis B virus (HBV) infection. Here, we investigated degranulation activity of circulating and intrahepatic natural killer (NK) cells from HBV and HCV chronically infected patients before any treatment (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M1"><mml:mi>n</mml:mi><mml:mo>=</mml:mo><mml:mn>125</mml:mn></mml:math>). The frequency of CD107 + NK cells in the female liver was significantly higher compared to that in males during chronic HBV infection (<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M2"><mml:mi>p</mml:mi><mml:mo>=</mml:mo><mml:mn>0.002</mml:mn></mml:math>) and correlated with the plasma levels of estradiol (correlation coefficient<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M3"><mml:mi>r</mml:mi><mml:mo>=</mml:mo><mml:mn>0.634</mml:mn></mml:math>;<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" id="M4"><mml:mi>p</mml:mi><mml:mo>&lt;</mml:mo><mml:mn>0.0001</mml:mn></mml:math>). Our results clearly show sex differences in degranulation activity of intrahepatic NK cells of HBV-infected patients. This probably contributes to the ability of females to better deal with HBV disease.