Correlation between miR-122 and IFN-γ cytokines in infant cytomegalovirus hepatitis

Infant cytomegalovirus hepatitis is one disease caused by cytomegalovirus (CMV) infection. CMV can be transmitted by mother-infant pathway. Most CMV infection had insidious onset, with jaundice, liver hypertrophy and dysfunction, with liver sclerosis and failure in severe cases. The mechanism of infant CMB hepatitis is still unclear yet. Recent studies showed the involvement of microRNA-122 (miR-122) in liver development, genetic regulation and functional metabolism. This study thus investigated the expression of miR-122 and CMV-DNA in patient blood to investigate the role of miR-122 in disease onset. 55 CMV hepatitis patients and 27 healthy control individuals were collected for blood samples, from which enzyme linked immunosorbent assay (ELISA) was employed to quantify serum IFN-gamma and TNF-alpha levels. MiR-122 content was tested by real-time fluorescent quantitative PCR. CMV hepatitis patients had elevated levels of miR-122, IFN-gamma and TNF-alpha compared to healthy controls (P < 0.05). After 1-month treatment, curing and improving infants had significantly lowered miR-122, IFN-gamma and TNF-alpha levels (P < 0.05) while incurring group had no significant differences (P > 0.05). Their expression levels were also positively correlated with CMV-DNA contents. Cytokines including IFN-gamma and TNF-alpha play an important role during the onset of CMV hepatitis, as is positively correlated with body's CMV-DNA contents.