Hepatitis C virus (HCV) and hepatitis B virus (HBV) can coinfect the same hepatocyte in the liver of patients with chronic HCV and occult HBV infection.

In this work, we have shown that hepatitis C virus (HCV) and hepatitis B virus (HBV) can coexist in the same hepatocyte using double fluorescent in situ hybridization in liver biopsy samples from patients with chronic HCV infection with occult HBV infection. Digital image analysis of hybridization signals showed that the HBV DNA levels in coinfected hepatocytes were lower than those in cells infected only with HBV. This finding supports the hypothesis of inhibition of HBV replication by HCV. Furthermore, HCV RNA levels were lower in coinfected cells than in cells infected only with HCV, suggesting that HBV may also inhibit HCV replication.

Hepatitis C virus replicates in peripheral blood mononuclear cells of patients with occult hepatitis C virus infection.

BACKGROUND: Occult hepatitis C virus (HCV) infection is characterised by the presence of HCV-RNA in the liver in the absence of anti-HCV, and serum viral RNA. Up to 70% of these patients also have HCV-RNA in peripheral blood mononuclear cells (PBMC) but it is not known if HCV is replicating in these cells. AIM: We studied possible HCV replication in PBMC of 18 patients with an occult HCV infection who were selected on the basis of HCV-RNA positivity in PBMC. METHODS: Detection of HCV-RNA positive and negative strands in PBMC was done by strand specific reverse transcriptase-polymerase chain reaction (RT-PCR) and by in situ hybridisation. RESULTS: The presence of HCV-RNA positive strand in PBMC was confirmed in all patients by strand specific RT-PCR and by in situ hybridisation. Mean percentage of PBMC which had the HCV-RNA positive strand was 3.3% (95% confidence interval (CI) 2.1-4.4) The HCV-RNA negative strand was found in the PBMC of 11/18 (61%) patients by strand specific RT-PCR and confirmed by in situ hybridisation, and the percentage of PBMC harbouring the HCV-RNA negative strand was 3.1% (95% CI 0.8-5.5). There was a significant correlation (p = 0.001, r = 0.84) between the percentage of PBMC with the HCV-RNA positive strand and that of PBMC with the HCV-RNA negative strand. CONCLUSION: HCV replicates in the PBMC of patients with occult HCV infection and thus, although these patients do not have serum HCV-RNA, they could be potentially infectious.

Replicación del virus de la hepatitis C en lesiones cutáneas de liquen plano / Hepatitis C virus replication in lichen planus lesions

El liquen plano (LP) es una enfermedad dermatológica cuya etiología es desconocida. En la última década se ha constatado en estudios epidemiológicos una asociación estadísticamente significativa entre dicha enfermedad y la infección crónica por virus de la hepatitis C (VHC). El objetivo de este estudio es investigar si el VHC está presente en las lesiones de LP para así obtener datos que apoyen un papel etiopatogénico del VHC en la inducción de lesiones de LP. Con este fin se ha analizado mediante hibridación in situ la presencia de VHC-RNA genómico y antigenómico en biopsias cutáneas procedentes de 32 pacientes con hepatitis crónica C (26 pacientes en los que la biopsia procedía de piel sana de tronco y 6 pacientes en los que era de piel sana facial), 24 pacientes con LP (5 con y 19 sin infección por VHC) y 6 pacientes sanos.Se detectó VHC-RNA en los queratinocitos del 69,2 por ciento y del 100 por ciento de los pacientes con hepatitis crónica C y piel sana, de tronco y facial respectivamente; en el 100 por ciento de los pacientes con hepatitis crónica C y LP y en ninguno de los pacientes sin hepatitis crónica C pero con LP. El porcentaje de queratinocitos que mostraban VHC-RNA genómico o antigenómico fue estadísticamente menor (p < 0,01) en la piel sana de tronco (5,7 ñ 3,5 por ciento y 2,7 ñ 3,1 por ciento de los queratinocitos con VHC-RNA genómico o antigenómico, respectivamente) que en las lesiones de LP (31,7 ñ 7,9 por ciento y 18,8 ñ 7,4 por ciento) o la piel adyacente no afecta (24,8 ñ 6,9 por ciento y 14,3 ñ 3,8 por ciento). Como conclusión, en este estudio se ha demostrado que el VHC infecta y replica en los queratinocitos de la piel de pacientes con hepatitis crónica C, independientemente de que presenten o no lesiones de LP. El hecho de que el porcentaje de queratinocitos infectados por VHC fuese significativamente mayor en las lesiones de LP que en las pieles dermatológicamente sanas, sugiere que la infección de los queratinocitos por VHC podría ser el agente etiopatogénico del desarrollo de las lesiones de LP cutáneo en estos pacientes, debiéndose aclarar esta cuestión en trabajos futuros (AU)

An in vitro study on the kinetics, subcellular distribution and phototoxicity of harmine in human tumor cells.

The beta-carboline alkaloid harmine, which was found to possess interesting phototoxic properties in different biological systems, was investigated for photokilling of human tumor cells in vitro. Harmine was readily accumulated by HeLa cells, localized preferably in cytoplasm, being a non toxic compound when used at low concentrations. The photoactivation of harmine-loaded cells with UV radiation showed lysosomal damage, reflected by altered localization of the fluorescent probe acridine orange, as well as an evident cell killing which increase with time up to a maximal value 48 h after the photodynamic treatment.

Detección del virus C de la hepatitis en lesiones cutáneas de liquen plano / Detection of hepatitis C virus in lichen planus lesions

Objetivos: Estudios epidemiológicos han demostrado una correlación entre el liquen plano y la hepatitis crónica por virus C. Para el conocimiento del papel que pueda desempeñar el VCH en el desarrollo de las lesiones de liquen plano, es necesario obtener evidencias morfológicas de la presencia del VCH en esta afección cutánea. Pacientes y métodos: Se ha analizado por hibridación in situ la presencia de VCH-RNA en biopsias de piel de 23 pacientes divididos en tres grupos: 1) once pacientes con liquen plano (cinco con VCH-RNA en suero); 2) seis pacientes sin liquen plano y con VCH-RNA en suero, y 3) seis sin liquen plano ni hepatopatía por VCH. Resultados: El VCH-RNA se detectaba en los queratinocitos de la piel de los pacientes con RNA del virus en suero independientemente de si tenían liquen plano o no y en ninguno de los casos VCH negativos. El porcentaje de células infectadas oscilaba desde un 13,1 per cent a un 44,26 per cent. Conclusión: Se ha demostrado que el VCH infecta los queratinocitos de la piel de los pacientes con hepatitis crónica C tanto en lesiones de liquen plano como de piel sana. Se necesitan investigaciones en esta línea para esclarecer las consecuencias patológicas de este hallazgo (AU)

TT virus detection in oral lichen planus lesions.

Epidemiological studies have demonstrated a correlation between oral lichen planus and different liver diseases. The new virus termed TT virus (TTV) is highly prevalent in patients with chronic hepatitis of different etiology and it may be speculated that TT virus may be involved in the pathogenesis of oral lichen planus. This study examined the presence of TT virus DNA in serum by PCR and in oral mucosa biopsies by in situ hybridization from 20 patients with oral lichen planus (13 with chronic hepatitis and seven without liver disease). Serum and oral mucosa biopsies from six patients all with chronic hepatitis with leukoplakia were also studied as controls. TT virus DNA was positive in the serum of 17/20 (85%) of the patients with oral lichen planus and in all the controls. TT virus DNA hybridization signals were detected in mucosa biopsies from all the patients with TT virus DNA in serum but in none of the three cases without this marker. The percentage of positive cells ranged from 1.6-80%. No differences were found in the percentage of positive cells between TT virus positive patients with and without oral lichen planus and there was no relationship between the number of positive cells and the intensity of the inflammatory infiltrate. In conclusion, TT virus infects oral epithelial cells but the results do not support a role for TT virus in causing oral lichen planus.

Prevalence of hepatitis B, hepatitis C, GB virus C/hepatitis G and TT viruses in predialysis and hemodialysis patients.

Patients with chronic renal failure on hemodialysis have a high risk of infections with viruses such as hepatitis B (HBV), hepatitis C (HCV), GB virus C/hepatitis G (GBV-C/HGV) and TT (TTV) viruses. The prevalence of HBV, HCV, GBV-C/HGV and TTV in patients with chronic renal failure who are on conservative management before entering into a hemodialysis program (predialysis) in comparison with hemodialyzed patients was studied to elucidate whether the high prevalence of these viruses is influenced by that observed in the predialysis stage. The presence of hepatitis B virus surface antigen (HBsAg), HCV RNA, GBV-C/HGV RNA and TTV DNA was analyzed in sera from 80 patients with chronic renal failure (35 on predialysis and 45 on hemodialysis). HBsAg, HCV RNA, GBV-C/HGV RNA and TTV DNA were detected in one (2.8%), six (17.1%), eight (22.5%) and 16 (45.7%) of the 35 patients on predialysis. Two (5.7%) of these patients were coinfected with HCV and GBV-C/HGV, whereas six (17.1%) had GBV-C/HGV and TTV coinfection. In the 45 hemodialyzed patients, HBsAg, HCV RNA, GBV-C/HGV RNA and TTV DNA were detected in one (2.2%), two (4.4%), seven (15.5%) and 26 (57.7%). One (2.2%) patient had HBV and TTV coinfection, two (4.4%) HCV and TTV coinfection whereas four (8.8%) were coinfected with GBV-C/HGV and TTV. No differences regarding age, gender, previous surgery and number of transfusions were found between infected and uninfected patients within and between both groups. In conclusion, the prevalence of the viruses studied in predialysis may influence their prevalence in dialysis units.

In situ detection of hepatitis C virus RNA in salivary glands.

Chronic hepatitis C virus (HCV) infection has been associated with several extrahepatic manifestations, among these, to diseases with oral manifestations such as Sjögren's syndrome or sialadenitis. HCV-RNA has been detected in saliva and in salivary glands from patients with sialadenitis by polymerase chain reaction. However, morphological evidence of HCV replication in salivary gland cells is needed to support a role for HCV in causing sialadenitis or Sjögren's syndrome. We have used in situ hybridization and immunohistochemistry to analyze the presence of HCV-RNA of sense and antisense polarity and HCV core antigen, respectively, in salivary gland biopsies from 19 patients with chronic sialadenitis or Sjögren's syndrome (eight anti-HCV-positive; 11 anti-HCV-negative). HCV-RNA of both positive and negative polarity as well as HCV core antigen were detected in the epithelial cells of the salivary gland biopsies from all of the anti-HCV-positive patients but in none of the anti-HCV-negative cases. The percentage of HCV-infected cells ranged from 25 to 48.8% in the patients studied. In conclusion, we have shown that HCV infects and replicates in the epithelial cells from salivary glands of patients with Sjögren's syndrome or chronic sialadenitis. However, its implication in the pathogenesis of these diseases deserves future research.

Detection of TT virus DNA in liver biopsies by in situ hybridization.

A novel hepatitis-associated virus named TT virus (TTV) has been isolated. However, its hepatotropism has not been proven. We have retrospectively analyzed the presence of TTV-DNA by polymerase chain reaction (PCR) and in situ hybridization in liver biopsies from 30 patients with liver disease (15 TTV-DNA-positive and 15 TTV-DNA-negative in serum), and prospectively in serum and liver from eight patients with normal liver histology. TTV-DNA was detected by PCR in the liver from the 15 patients with serum TTV-DNA and in serum and liver of two of the eight patients without liver disease. TTV-DNA titers in liver were 10 times higher than in serum, although no correlation between TTV-DNA titers in serum and liver were observed. In situ hybridization shows positive signals in the hepatocytes of the 17 patients infected by TTV but in none of the TTV-DNA-negative patients by PCR. No morphological changes were observed in the hepatocytes showing hybridization signals. The percentage of positive hepatocytes ranged from 2.1% to 30% and correlated with the TTV-DNA titers in liver (r = 0.54; P = 0.037). In conclusion, our results show that TTV is able to infect liver cells although they do not support a role for TTV in causing liver disease.

Prevalence of TT virus in serum and peripheral mononuclear cells from a CAPD population.

BACKGROUND: A novel virus named TT virus (TTV) has been isolated recently from patients with posttransfusional hepatitis of unknown etiology. The prevalence of TTV in several groups at risk has been reported, however, there is no information about the prevalence of TTV in patients on continuous ambulatory peritoneal dialysis (CAPD) without blood transfusions or hemodialysis antecedents. OBJECTIVE: To study the incidence of TTV in serum and peripheral blood mononuclear cells (PBMC) of CAPD patients. DESIGN: TTV DNA was detected by polymerase chain reaction, using primers from the open reading frames (ORF) 1 and 2, in serum and PBMC from 22 CAPD patients who had not received blood transfusions or hemodialysis therapy prior to CAPD. As controls, sera from 20 patients with chronic viral hepatitis (10 with HBV and 10 with HCV) and 20 healthy donors were included in the study. RESULTS: TTV DNA was detected in the serum of 5 of 22 (22.7%) CAPD patients with both sets of primers. Four of the 5 (80%) patients with TTV DNA in their serum were TTV positive in their PBMC with primers from ORF1 and ORF2. Five of 20 (25%) patients with chronic viral hepatitis (2 patients with HBV and 3 with HCV) and 4 of 20 (20%) healthy donors were TTV DNA positive in serum. No relation was found between TTV infection and the underlying kidney disease, previous surgery, and abnormal alanine aminotransferase levels. CONCLUSION: We have found a relatively high prevalence of TTV that is similar to that found in healthy donors and in patients with chronic viral hepatitis.