Percentage of hepatitis C virus-infected hepatocytes is a better predictor of response than serum viremia levels.

Pegylated alpha-interferon plus ribavirin is the current therapy for chronic hepatitis C virus (HCV) infection. Serum HCV-RNA concentration before treatment has been identified as an independent predictive factor of response. We have compared the percentage of HCV-infected hepatocytes with the concentration of serum HCV-RNA in baseline samples as predictors of response.

Detection of human immunodeficiency virus type 1 RNA by in situ hybridization in oral mucosa epithelial cells from anti-HIV-1 positive patients.

Several in vitro studies have shown that HIV-1 can infect CD4 negative epithelial cells of different origin including normal human oral keratinocytes, but whether this infection of mucosal epithelial cells occurs in vivo is still unclear. In this report, the presence and cell types infected by HIV-1 in paraffin embedded oral mucosa biopsies from 17 anti-HIV-1 positive patients have been examined by in situ hybridization and immunohistochemistry. As controls, oral mucosa biopsies from eight patients without HIV-1 infection markers were also analyzed.

Hepatitis B infection of the liver in chronic hepatitis C without detectable hepatitis B virus DNA in serum.

Hepatitis B virus (HBV) DNA may persist in the liver in the absence of serum HBV-DNA after a self-limited acute hepatitis B. This may also occur in patients with chronic hepatitis C virus (HCV) infection but its prevalence and its impact on liver histology is unknown. HBV-DNA was tested by polymerase chain reaction (PCR) and by in situ hybridisation in liver biopsies from 98 patients with chronic hepatitis C who were hepatitis B surface antigen negative and serum HBV-DNA negative by PCR.

Occult hepatitis C virus infection in patients in whom the etiology of persistently abnormal results of liver-function tests is unknown.

Background: There are patients in whom the etiology of long-standing abnormal results of liver-function tests is unknown (ALF-EU) after exclusion of all known causes of liver diseases. We analyzed the presence of hepatitis C virus (HCV) RNA in liver-biopsy specimens from 100 patients who were negative for anti-HCV antibodies and for serum HCV RNA and who had ALF-EU.

Methods: HCV RNA status was tested by reverse-transcription polymerase chain reaction (RT-PCR) and by in situ hybridization, in liver and peripheral-blood mononuclear cells (PBMCs).

Distribution of hepatitis B virus in the liver of chronic hepatitis C patients with occult hepatitis B virus infection.

Although occult hepatitis B virus (HBV) infection (HBV-DNA in serum in the absence of hepatitis B surface antigen [HBsAg]) is common in chronic hepatitis C, its characteristics are not well known. In this work, the presence of HBV-DNA (by polymerase chain reaction; PCR) and its distribution (by in situ hybridization) in liver biopsies and peripheral blood mononuclear cells (PBMCs) from 32 patients with chronic hepatitis C and occult HBV infection and in 20 HBsAg chronic carriers were determined. The results showed that serum HBV-DNA levels were statistically lower (P = 0.

Detection of hepatitis C virus RNA and core protein in keratinocytes from patients with cutaneous lichen planus and chronic hepatitis C.

Cutaneous lichen planus has been associated in patients with chronic hepatitis C virus infection. It is still unknown whether hepatitis C virus infects keratinocytes of lichen planus lesions. In this report we have analyzed the presence of genomic and anti-genomic hepatitis C virus RNA in skin biopsies from 26 patients with chronic hepatitis C and healthy skin and from 24 patients with cutaneous lichen planus (five with and 19 without hepatitis C virus infection) by in situ hybridization.

Hepatitis C virus replicates in sweat glands and is released into sweat in patients with chronic hepatitis C.

Hepatitis C virus (HCV) replicates in salivary glands of chronic hepatitis C patients and is released into the saliva, suggesting that HCV may replicate in other exocrine glands. The presence of positive and negative HCV RNA strands was demonstrated by in situ hybridization, and of HCV core protein by immunohistochemistry, in sweat glands and keratinocytes in healthy skin biopsies from 15 patients with chronic hepatitis C and 10 anti-HCV negative patients with chronic liver disease. Positive and negative HCV RNA strands were detected in 9.

TT virus replicates in stimulated but not in nonstimulated peripheral blood mononuclear cells.

TT virus (TTV) is an unenveloped, single-stranded, circular-DNA virus which resembles members of the Circoviridae, that is commonly found in humans and which lacks pathological consequences for the infected host. TTV replication has been demonstrated in bone marrow cells but not in peripheral blood mononuclear cells (PBMC), suggesting that hematopoietic cells must be activated to support TTV replication. To test this hypothesis, PBMC from two naturally TTV-infected individuals and from two healthy TTV-DNA negative donors infected in vitro with a TTV-DNA-positive serum were cultured in the presence (stimulated) or absence (unstimulated) of phytohemagglutinin, lipopolysaccharide, and interleukin-2.