Reactivation of Epstein-Barr virus in B cells of patients with chronic hepatitis C.

Hepatitis C virus (HCV) infection is associated with lymphoproliferative disorders. HCV infection of B cells is a predictive factor for lymphoproliferative disorders in patients with chronic hepatitis C, although its molecular mechanisms remain unknown. Epstein-Barr virus (EBV) is a B cell-tropic virus with the potential to cause lymphoproliferative disorders, and its reactivation is induced by several viruses and cytokines. The possibility that HCV infection triggers reactivation of EBV and induces lymphoproliferative disorders were investigated. Expression of EBV mRNAs was analyzed by RT-PCR in patients infected with HCV and control subjects, and correlations between reactivation of EBV and markers for lymphoproliferative disorders were investigated. BZLF1 mRNA, a starter molecule of reactivation, was detected in peripheral blood mononuclear cells from 12 of 52 (23%), patients infected with HCV and the frequency was higher than in healthy subjects [3 of 43 (9%), P = 0.032]. But the presence of the BZLF1 mRNA was not associated with an abnormality of markers for lymphoproliferative disorders. This study on BZLF1 mRNA expression among lymphoid cell subsets showed that reactivation of EBV was observed specifically in B cells. The BZLF1 mRNA disappeared following anti-viral therapy and remained negative after eradication of HCV in patients with a sustained viral response, while the EBER1 RNA, a marker for persistence of EBV, was detected throughout the therapy. Infection with HCV induces reactivation of EBV in B cells, but this reactivation was not associated directly with lymphoproliferative disorders triggered by HCV.

Infection of B cells with hepatitis C virus for the development of lymphoproliferative disorders in patients with chronic hepatitis C.

Infection with hepatitis C virus (HCV) is associated with lymphoproliferative disorders, represented by essential mixed cryoglobulinemia and B-cell non-Hodgkin's lymphoma, but the pathogenic mechanism remains obscure. HCV may infect B cells or interact with their cell surface receptors, and induce lymphoproliferation. The influence of HCV infection of B cells on the development of lymphoproliferative disorders was evaluated in 75 patients with persistent HCV infection. HCV infection was more prevalent (63% vs. 16%, 14%, or 17% P < 0.05 for each), and HCV RNA levels were higher (3.35 +/- 3.85 vs. 1.75 +/- 2.52, 2.15 +/- 2.94 or 2.10 +/- 2.90 log copies/100 ng, P < 0.01 for each) in B cells than CD4(+), CD8(+) T cells or other cells. Negative-strand HCV RNA, as a marker of viral replication, was detected in B cells from four of the 75 (5%) patients. Markers for lymphoproliferative disorders were more frequent in the 50 patients with chronic hepatitis C than the 32 with chronic hepatitis B, including cryoglobulinemia (26% vs. 0%, P < 0.001), low CH(50) levels (48% vs. 3%, P = 0.012), and the clonality of B cells (12% vs. 0%, P < 0.01). By multivariate analysis, HCV RNA in B cells was an independent factor associated with the presence of at least one marker for lymphoproliferation (odds ratio: 1.98 [95% confidence interval: 1.36-7.24], P = 0.027). Based on the results obtained, the infection of B cells with HCV would play an important role in the development of lymphoproliferative disorders.

[Two cases of gastric cancer expressing Glypican 3, but producing AFP with different lectin affinity].

We encountered 2 cases of AFP-producing gastric cancer. In the first patient, an 82-year-old man was found to have advanced type II advanced carcinoma in the stomach with a massive tumor embolus in the portal vein. In the second case, an 80-year-old man was given a diagnosis of multiple liver metastases of gastric cancer with portal vein thrombosis. Our diagnosis of gastric cancer in both cases was AFP-producing. It was supposed that the elevation of serum level of AFP might be caused by enteroblastic differentiation in the first case and hepatoid differentiation in the second case. Although, in both cases, the biopsy specimens of the gastric neoplasm proved moderately to poorly differentiated adenocarcinoma without hepatoid differentiation, the localization of Glypican 3 in gastric cancer cells was observed using immunostaining with a monoclonal antibody. In both cases, Glypican 3 was a sensitive and useful marker for AFP-producing gastric cancer with or without hepatoid differentiation.

Two cases of tuberculous peritonitis with liver cirrhosis complicated by refractory ascites.

We present two cases of tuberculous peritonitis with liver cirrhosis complicated by refractory ascites. Case 1 was a 59-year-old female with alcoholic liver cirrhosis. She was admitted to our hospital because of diarrhea, anorexia and inflammatory reactions on a blood test. She had a high fever of 38°C or more and refractory ascites. Tubercle bacilli infection was suspected based on increased levels of serum CA125 and adenosine deaminase (ADA) in ascites. Laparoscopic examination showed white nodules on the peritoneum, and histologic study confirmed tuberculous nodules. The same bacteria were isolated from culture of ascites. Case 2 was a 55-year-old female with hepatitis C virus-infected liver cirrhosis. She was admitted because of high fever and abdominal fullness due to ascites. High levels of serum CA125 and ADA in ascites and ineffectiveness of treatment with antibiotics plus diuretics led us to start anti-tuberculous therapy before definitive diagnosis. Tuberculus bacillus was later isolated from culture of ascites. It is difficult to make early diagnosis of tuberculous peritonitis in cirrhotic patients with ascites due to a lack of specific symptoms. However, determination of serum CA125 and ADA in ascites and the acid-fast bacterial culture of ascites are useful for early diagnosis.

Translational enhancement of HCV RNA genotype 1b by 3'-untranslated and envelope 2 protein-coding sequences.

HCV RNA has a unique regulatory mechanism for translation. The X region of 3'-UTR and core-coding sequence regulate HCV translation. In this study, we clarified that the entire 3'-UTR also enhances HCV translation, and the envelope-coding sequence of HCV genotype 1b increases degree of this enhancement. In the luciferase reporter assay using rabbit reticulocyte lysates, translational enhancement by 3'-UTR with core to E2 regions was 25-fold higher when compared with control RNA lacking the 3'-UTR. Presence of the entire E2 sequence was important for this enhancement. This phenomenon was not due to transcript stability, and envelope protein alone did not affect translation. E2-coding sequence of genotype 1a had no effect on translation. We observed the same results in animal cell culture systems using bicistronic RNA. Structural protein-coding sequences and 3'-UTR of HCV RNA regulate viral translation, and a target for antiviral agents may be present in these regions.