A human T-cell clone cytotoxic for hepatocytes from patients with chronic non-A, non-B hepatitis

A human T-cell clone (TA-NB-2) which could lyse hepatocytes from patients with chronic non-A, non-B (NANB) hepatitis was established (Proc Natl Acad Sci USA 1989;86:2883–2887). TA-NB-2 cells belonged to CD3⁺ CD8⁺ cytotoxic T lymphocytes, and recognized the target hepatocytes by T-cell receptor without restriction by major histocompatibility complex (MHC) antigens. TA-NB-2 cells significantly lysed hepatocytes from 22 of 23 patients with chronic NANB hepatitis, whereas they lysed hepatocytes from only one of 17 control patients with chronic type B hepatitis, acute hepatitis B or acute hepatitis A. TA-NB-2 cells also significantly lysed hepatocytes from 4 of 5 patients with autoimmune liver disease. The results suggest that TA-NB-2 cells specifically recognize a NANB hepatitis-related antigen expressed on NANB hepatitis virus-infected hepatocytes by T-cell receptor in non-MHC-restricted manner. The results also suggest that most, if not all, cases of chronic NANB hepatitis are caused by one agent and that a portion of cases of autoimmune liver disease may be induced by infection with a NANB hepatitis virus. The authors are grateful to Sachiyo Terada for her skillful technical assistance. This study was supported in part by a Grant-in-Aid for Cancer Research (63-8) from the Ministry of Health and Welfare, Japan.     

Cellular cytotoxicity against autologous hepatocytes in acute and chronic non-A, non-B hepatitis.

In a microcytotoxicity assay we tested lymphocyte cytotoxicity against autologous hepatocytes. The following cytotoxicity values were found (given mean +/- SEM): acute non-A, non-B (NANB) hepatitis 45.7 +/- 4.3% (n = 7), chronic NANB hepatitis 32.8 +/- 5.1% (n = 11), chronic active hepatitis B (CAH-B) 27.7 +/- 6.7% (n = 10), toxic lesions 18.1 +/- 4.2% (n = 18), controls with normal liver histology or minimal changes 4.9 +/- 2.5% (n = 8). Thus our study shows enhanced cellular cytotoxicity in acute and chronic NANB hepatitis and indicates that T cells as well as non-T cells have cytotoxic effector functions. These findings are similar to those obtained in CAH-B and suggest that cellular immune reactions play an important role in the course of NANB hepatitis. For comparison we tested cytotoxic reactions in toxic lesions. They were only moderate and well distinguishable from those observed in NANB hepatitis and CAH-B; they even may be unspecific. No correlation was seen between cytotoxicity and aminotransferase concentrations.     

Study of an epidemic of non-A,non-B hepatitis: Possibility of another human hepatitis virus distinct from post-transfusion non-A,non-B type

A common source waterborne epidemic of viral hepatitis was studied in Kashmir valley over the six month period from November 1978 to April 1979. Highly sensitive serologic tests for hepatitis B and hepatitis A failed to reveal either one as an etiologic agent of hepatitis. Of 16,620 inhabitants of the area screened four times in these six months, viral hepatitis developed in 1.65 per cent. In addition, 27.3 per cent of 128 persons who had contacts with patiente who had viral hepatitis had biochemical features of anicteric hepatitis. The mode of spread of the epidemic, length of incubation, clinical features and biochemical test results of the patients studied resembled that of hepatitis A. These findings were in contrast to that of non-A, non-B hepatitis following transfusion, which closely resembles hepatitis B. The data strongly suggest the possibility of another human hepatitis virus and established the fecal oral route of its spread.     

Nuclear changes in hepatocytes of patients with non-A, non-B hepatitis

Experimental non-A, non-B hepatitis infection has been shown to produce two distinct ultrastructural changes in chimpanzees: intranuclear particles and intracytoplasmic tubular structures. We report our observations of intranuclear particles in humans with acute non-A, non-B hepatitis. These particles appear to be specific for at least one type of non-A, non-B hepatitis.     

Molecular cloning of the human hepatitis C virus genome from Japanese patients with non-A, non-B hepatitis.

The nucleotide sequence of the Japanese type of hepatitis C virus (HCV-J) genome, consisting of 9413 nucleotides, was determined by analyses of cDNA clones from plasma specimens from Japanese patients with chronic hepatitis. HCV-J genome contains a long open reading frame that can encode a sequence of 3010 amino acid residues. Comparison of HCV-J with the American isolate of HCV showed 22.6% difference in nucleotide sequence and 15.1% difference in amino acid sequence. Thus HCV-J and the American isolate of HCV are probably different subtypes of HCV. The relationship of HCV-J with other animal RNA virus families and the putative organization of the HCV-J genome are discussed.     

Search for hepatitis B virus DNA in sera from patients with acute type B or non-A, non-B hepatitis

One hundred and three single sera from adults hospitalized with acute type B (78) or non-A, non-B (25) hepatitis were tested for the presence of hepatitis B virus DNA (HBV DNA). All sera from patients with type B hepatitis were IgM anti-HBc-positive. These patients were classified as benign (47) or fulminant (31) hepatitis. The 25 acute non-A, non-B patients were also classified as benign (21) or fulminant (4) hepatitis and were negative for serologic markers of past HBV infection. Serum HBV DNA was detected with similar frequency in benign (38.5%) and fulminant (FH, 34.6%) HBsAg-positive cases. HBV DNA was not detected in either the 26 acute HBsAg-negative hepatitis B cases who were positive for anti-HBc and anti-HBs or the 25 acute non-A, non-B hepatitis cases. The absence of HBV DNA in 43.8% of benign hepatitis B patients who were positive for HBsAg and HBeAg could possibly be attributed to either low level replication of HBV that was not detectable by the [32P]HBV DNA probe or to a period of delayed clearance of free HBeAg following cessation of HBV replication. Emergence of anti-HBs in the presence of HBsAg did not always correspond to clearance of HBV in fulminant type B cases. However, in acute type B hepatitis, irrespectively of severity, disappearance of HBsAg and appearance of anti-HBs was accompanied by reduction of HBV replication to undetectable levels.     

Rapidly progressive non-A, non-B hepatitis in patients with human immunodeficiency virus infection

No information is available on the role of non-A, non-B hepatitis in the various hepatic abnormalities described in patients with the acquired immune deficiency syndrome. Of 97 patients referred with suspected non-A, non-B hepatitis, 3 were found to have antibody to the human immunodeficiency virus. These latter 3 patients all developed symptomatic cirrhosis within 3 yr of onset of hepatitis. Such a rapid progression of liver disease was rare in patients with non-A, non-B hepatitis who did not have simultaneous human immunodeficiency infection. These findings suggest that human immunodeficiency virus infection may potentiate the liver injury of chronic non-A, non-B hepatitis.     

The chronic sequelae of non-A, non-B hepatitis.

Twenty-six of 388 patients (6.7%) followed prospectively after open-heart surgery developed non-A, non-B hepatitis. Of these 26, 12 had an elevated (often fluctuating) serum alanine aminotransferase (SGPT) for greater than 1 year. Liver biopsy, done in eight of 12, showed chronic active hepatitis in six and chronic persistent hepatitis in two; one patient with chronic active hepatitis had early cirrhosis. Anicteric patients with peak SGPT greater then 300 IU/L were at greatest risk of developing chronic hepatitis. Chronic non-A, non-B hepatitis was symptomatically mild and unaccompanied by physical signs or laboratory evidence of autoimmune disease or severe chronic liver disease. In all 12 patients there was spontaneous improvement in serum transaminase over a period of 1 to 3 years, and four patients had sustained normalization of SGPT. Thus chronic active hepatitis is a common sequela of acute non-A, non-B hepatitis but may have a better prognosis than chronic active hepatitis of other causes.     

Hepatitis C virus antibodies in acute icteric and chronic non-A, non-B hepatitis.

Hepatitis C virus antibodies were measured in 213 patients who had acute (n = 122) and chronic (n = 91) non-A, non-B hepatitis. In acute infection, anti-hepatitis C virus was detected in 61% of IV drug abusers, in 33% of patients with transfusion-associated hepatitis, and in 22% of patients with sporadic infections (P less than 0.0005, drug abusers vs. sporadic). Mean time to seroconversion was 11.6 weeks (range, 1-80 weeks). Anti-hepatitis C virus was more common in chronic infection (P less than 0.001) and was more often detected in IV drug users (89%; P less than 0.0001) and after transfusion (71%; P less than 0.005) compared with chronic sporadic infection (27%). Antibody persisted for up to 8 years. Six chronic case patients (8.3%) later lost antibody (mean, 24 months; range, 12-48 months).     

Recombinant human alpha-interferon in patients with chronic non-A, non-B hepatitis: a multicenter randomized controlled trial from France

We have conducted a multicenter randomized controlled trial comparing two doses of recombinant human alpha-interferon for efficacy in 60 patients with chronic non-A, non-B hepatitis. The source of infection appeared to be transfusion in 30 patients, intravenous drug abuse in 16 patients and was unknown in 14 patients. Patients were randomly assigned to no treatment or to treatment with either 1 or 3 MU of alpha-interferon given three times a week for 24 wk. Forty-five patients (75%) were positive for antibody to hepatitis C virus. During the 24-wk treatment period, mean serum ALT levels decreased in both treatment groups, but the decrease was statistically significant only in the 3 MU group. However, at 24 wk, the proportion of patients with normal ALT levels was similar in the 3 MU group (39%) and the 1 MU group (45%), and both were significantly higher than in controls (0%). Repeat liver biopsy specimens showed a significant decrease in the severity of histological changes in the 3 MU group but not in the 1 MU group or in controls. Responses to alpha-interferon did not correlate with patient's age, gender, source of infection, pretreatment serum ALT, presence of anti-hepatitis C virus or cirrhosis. After treatment, the mean ALT levels rose in both treated groups. The proportion of patients with normal ALT levels at wk 48 was 28% in the 3 MU group and 20% in the 1 MU group. In conclusion, a dose of 3 MU was superior to 1 MU of alpha-interferon given three times weekly for 24 wk in inducing improvements in serum ALT levels and liver histological examinations.(ABSTRACT TRUNCATED AT 250 WORDS)     

Detection of hepatitis C virus RNA in chronic non-A, non-B liver disease.

Serum samples were tested for detection of hepatitis C virus (HCV) RNA from 156 patients with chronic non-A, non-B liver disease. HCV RNA was detected in 121 (93.8%) of 129 patients positive for anti-C100-3 but was also found in 15 (55.6%) of 27 patients negative for anti-C100-3. The rate of positivity for HCV RNA was not significantly different among various stages of liver diseases. These results showed that HCV continues to replicate even in advanced liver disease and that it seems to be related to half of the cases of chronic non-A, non-B liver disease negative for anti-C100-3.     

Serum hepatitis C virus RNA and hepatitis B virus DNA in non-A, non-B post-transfusional and sporadic chronic hepatitis.

The sera of 36 French patients with post-transfusional and sporadic non-A, non-B chronic hepatitis were investigated, for HBV and HCV infections using a combination of serological and polymerase chain reaction (PCR) assays. Anti-HCV was detected in 75% (27/36) of the patients by ELISA1 and/or RIBA2 tests. HCV-RNA sequences were found in 75% (27/36) of the sera by a single step PCR, using a set of primers located in the 5' non-coding region. Altogether, 89% (32/36) of the patients were found positive with serological and/or molecular tests. Among the positive patients, 68% (22/32) were found positive for both anti-HCV and HCV-RNA, 16% (5/32) and 16% (5/32) were found positive for either anti-HCV or HCV-RNA, respectively. HBV-DNA sequences were detected in two patients associated to the HCV viraemia. This study confirms the extremely high prevalence of HCV infection in NANB chronic hepatitis in France. It also shows possible co-infection by HCV and HBV in hepatitis.     

Long-term intermittent administration of interferon-alpha in patients with chronic non-A, non-B hepatitis

IFN-alpha was administered intermittently over a 6 month period in 39 patients with chronic non-A, non-B hepatitis confirmed by peritoneoscopy and liver biopsy. Three million units of IFN-alpha were administered 3 times a week for the first 6 months then twice, then once a week. In 26 patients (67%), GPT decreased and remained within the normal range during the course of administration, and in 9 patients (23%) GPT remained normal for over 6 months after the discontinuation of IFN-alpha. There was no significant difference of efficacy among 3 groups liver histology groups (CPH, CAH-2A, and CAH-2B), but GPT decreased significantly in patients with sporadic hepatitis compared to patients with a history of blood transfusion. Furthermore, GPT decreased significantly in patients with a history of a blood transfusion within the preceding 2 years compared to patients with a history of a blood transfusion over 7 years ago. GPT increased markedly after an early tapering to 2 doses weekly, but it did not increase after a 6 month administration. In conclusion, the long-term administration of 300 million unit IFN-alpha, 3 times weekly for 6 months, about 2.5 hundred million units in total, is thought to be an effective way to control chronic NANB hepatitis.     

Hepatitis C virus RNA genome in plasma of patients with non-A, non-B hepatitis.

Recently, the assay system of anti-hepatitis C virus antibody (HCV-Ab) was developed. However, there is no clinically useful method to detect hepatitis C virus (HCV) itself. The authors recently developed a method to detect the HCV-RNA genome in plasma using polymerase chain reaction (PCR). In the present study, the specificity of this assay in detecting HCV infection was investigated. Freshly obtained 1 ml plasma specimens from 100 patients with various liver diseases and from 11 control subjects were studied. In patients with non-A, non-B (NANB) hepatitis-related liver diseases, HCV-RNA was detected in 2 out of 7 cases of acute hepatitis, in 29 out of 31 cases of chronic hepatitis, in 17 out of 21 cases of cirrhosis and in 2 out of 6 cases of hepatocellular carcinoma. On the other hand, no HCV-RNA was detected in 15 cases of various types of alcoholic liver diseases, in 12 cases of hepatitis B related liver diseases, and in 11 controls. HCV-RNA was detected in 2 of 6 drinkers with chronic hepatitis. The prevalence of HCV-RNA was not closely related to a history of blood transfusions. These results suggest that our method for HCV-RNA is specific for HCV infection and HCV infection is the likely etiology of most chronic NANB hepatitis cases. The clinical usefulness of our method is illustrated by the fact that we were able to study 100 patients and needed only 1 ml plasma per HCV-RNA assay.     

The virus of non-A, non-B hepatitis. Serological diagnosis]

Persistence of viral post-transfusion hepatitis together with epidemiological data led to identify 3 forms of clinical non A non B hepatitis: enteric, post-transfusional and sporadic hepatitis. Two groups of viruses are responsible for this pathology; they are designated as HEV (Hepatitis E Virus) and HCV (Hepatitis C Virus). HEV described by D. Bradley is a 27 to 34 nm. non enveloped particle containing a single strand RNA and belonging to the calicivividae family. HCV described by M. Houghton is a 50 to 60 nm. enveloped virus containing a 10,000 nucleotide long single strand RNA who belongs to the Flaviviridae family. The serological diagnosis is based on the detection of antibodies against the C100-3 antigen, a 363 amino acid recombinant protein produced in yeasts. Reactive samples are to be confirmed for antibodies specificity by using a neutralization assay in the presence of the same antigenic material. Alternatively, it is also possible to identify some sequences of viral genome in the serum, after amplification by the technic of Polymerase Chain Reaction (PCR).