HCV viremia drives an increment of CD86 expression by myeloid dendritic cells

Abstract

The host immune response, including innate and adaptive immunity, plays a critical role in determining the outcome of viral infection. Nevertheless, little is known about the exact reasons for the failure of the host immune system in controlling hepatitis C virus (HCV) infection. Impairment of dendritic cells (DCs) function is probably one of the mechanisms responsible for immune evasion of HCV. In this study, the frequency and phenotype of DCs subsets were analyzed in three groups: HCV-infected individuals who developed viral persistence (1), HCV-infected individuals who spontaneously cleared the virus (2) and HCV-seronegative uninfected subjects (3). The results showed that the frequency of DCs subsets was not statistically significant between groups. Plasmacytoid DCs circulating exhibited an immature phenotype characterized by low expression of CD86. On the other hand, CD86 expression in myeloid DCs was significantly higher in chronic infected individuals compared to healthy controls (P=0.037). A positive correlation was observed between CD86(+) myeloid DC (mDC) and HCV viral load (r=0.4121, P=0.0263). These results suggest that HCV did not have an inhibitory effect on mDC maturation and the HCV viremia drives the increase of CD86 expression in mDC. The regulation of DCs maturation and migration lies at the level of intracellular signaling. HCV can activate or block intracellular signaling pathways and alter DC function. In conclusion, the present study suggests that imbalance of DC maturation by the virus represents a mechanism of evasion of the immune system despite the fact that HCV viremia appears to exert a "stimulatory" effect on cell-surface immune phenotype.

Effects of porcine epidemic diarrhea virus on porcine monocyte-derived dendritic cells and intestinal dendritic cells

“…Some viruses utilize strategies to promote or inhibit DCs function by affecting cellular maturation, pro-inflammatory cytokine secretion and antigen presentation in vitro (Cespedes et al, 2013;Malta et al, 2013). In order to determine whether CV777 affects DCs, we have examined DC function in vitro.…”

Neopterin and soluble CD14 levels as indicators of immune activation in cases with low anti-HCV reactivity and true HCV infection

“…These DCs migrate to draining lymph nodes where they express HCV antigens on HLA class II molecules. After that, they stimulate the expression of co-stimulatory molecules (CD80 and CD86) which interact with and activate antigen-specific Th cells (Malta et al, 2013).…”

Investigation of the Immunomodulatory effect of Berberis vulgaris on core-pulsed dendritic cell vaccine

“…Compared to monocyte-derived DCs from healthy donors, DCs from patients with chronic HCV infection showed an impaired ability to stimulate allogeneic T cells and to produce interferon (INF) [33]. This impaired maturation of DCs has been correlated with persistent HCV infection, [34, 35] and that’s the main scope of the current study.…”