Mitogen-induced upregulation of hepatitis C virus expression in human lymphoid cells

Extrahepatic replication of HCV: insights into clinical manifestations and biological consequences

An estimated 170 million persons are infected with the hepatitis C virus (HCV) worldwide. While hepatocytes are the major site of infection, a broad clinical spectrum of extrahepatic complications and diseases are associated with chronic HCV infection, highlighting the involvement of HCV in a variety of non-hepatic pathogenic processes. There is a growing body of evidence to suggest that HCV can replicate efficiently in extrahepatic tissues and cell types, including peripheral blood mononuclear cells. Nonetheless, laboratory confirmation of HCV replication in extrahepatic sites is fraught with technical challenges, and in vitro systems to investigate extrahepatic replication of HCV are severely limited. Thus, future studies of extrahepatic replication should combine innovative in vitro assays with a prospective cohort design to maximize our understanding of this important phenomenon to the pathogenesis and treatment response rates of HCV.

Soluble egg antigen of Schistosoma Haematobium induces HCV replication in PBMC from patients with chronic HCV infection

BACKGROUND

This study was conducted to examine, in vitro , the effect of soluble egg antigen (SEA) of S. haematobium on intracellular HCV RNA load in peripheral mononuclear cells (PBMC) as well as on cell proliferation in patients with chronic HCV infection.

METHODS

PBMC from 26 patients with chronic HCV infection were cultured for 72 hours in presence and absence of 50 mug SEA/ml medium. Intracellular HCV RNA quantification of plus and minus strands was assessed before and after stimulation. PBMC from five healthy subjects were cultured for 7 days, flow cytometric analysis of DNA content was used to assess the mitogenic effect of SEA on PBMC proliferation compared to phytoheamaglutinine (PHA).

RESULTS

Quantification of the intracellular viral load showed increased copy number/cell of both or either viral strands after induction with SEA in 18 of 26 patients (69.2%) thus indicating stimulation of viral replication. Flow cytometric analysis showed that mean +/- S.D. of percent values of cell proliferation was induced from 3.2 +/- 1.5% in un-stimulated cells to 16.7 +/- 2.5 % and 16.84 +/- 1.7 % in cells stimulated with PHA and SEA respectively.

CONCLUSION

the present study supports earlier reports on SEA proliferative activity on PBMC and provides a strong evidence that the higher morbidity observed in patients co-infected with schistosomiasis and HCV is related, at least in part, to direct stimulation of viral replication by SEA.

Soluble egg antigen of Schistosoma Haematobium induces HCV replication in PBMC from patients with chronic HCV infection

BACKGROUND

This study was conducted to examine, in vitro , the effect of soluble egg antigen (SEA) of S. haematobium on intracellular HCV RNA load in peripheral mononuclear cells (PBMC) as well as on cell proliferation in patients with chronic HCV infection.

METHODS

PBMC from 26 patients with chronic HCV infection were cultured for 72 hours in presence and absence of 50 mug SEA/ml medium. Intracellular HCV RNA quantification of plus and minus strands was assessed before and after stimulation. PBMC from five healthy subjects were cultured for 7 days, flow cytometric analysis of DNA content was used to assess the mitogenic effect of SEA on PBMC proliferation compared to phytoheamaglutinine (PHA).

RESULTS

Quantification of the intracellular viral load showed increased copy number/cell of both or either viral strands after induction with SEA in 18 of 26 patients (69.2%) thus indicating stimulation of viral replication. Flow cytometric analysis showed that mean +/- S.D. of percent values of cell proliferation was induced from 3.2 +/- 1.5% in un-stimulated cells to 16.7 +/- 2.5 % and 16.84 +/- 1.7 % in cells stimulated with PHA and SEA respectively.

CONCLUSION

the present study supports earlier reports on SEA proliferative activity on PBMC and provides a strong evidence that the higher morbidity observed in patients co-infected with schistosomiasis and HCV is related, at least in part, to direct stimulation of viral replication by SEA.