Search PubMed⌕ Search

Biomedical subjects

S M Feinstone

Publications and source records attributed to S M Feinstone.

At least 109 records · Page 6Linked to original sources

Localization of hepatitis A antigen in liver tissue by peroxidase-conjugated antibody method: light and electron microscopic studies.

Hepatitis A antigen (HAAG) was localized in liver tissue from marmosets inoculated with human hepatitis A virus (HAV) by light and electron microscopy by using a peroxidase-conjugated antibody method. The fine granular peroxidase staining was scattered throughout the cytoplasm of liver cells when viewed with the light microscope. The distribution of HAAg-positive cells was focal. Virus-like particles, 24 to 27 nm in diameter, were observed in the cytoplasm of hepatocytes and smaller cells, resembling Kupffer cells, by standard thin-section electron microscopy (thin section EM). By immunoperoxidase electron microscopy (immunoperoxidase EM), HAAg was detected on the particles, which were aggregated within cytoplasmic vesicles of the hepatocyte. The surrounding membrane of the vesicles was also HAAg- positive. Similar HAAg particles were observed in the cytoplasm of smaller cells adjacent to hepatocytes as well. Thus, immunoperoxidase EM revealed that the 24- to 27-nm virus-like particles in the cytoplasm of liver cells obtained from marmosets were infected with HAV contained HAAg.

Animals↗

Non-A, non-B post-transfusion hepatitis.

To clarify the role of hepatitis-A virus (H.A.V.) in the aetiology of post-transfusion hepatitis unrelated to hepatitis-B virus, we have tested and titred pre-transfusion and convalescent serum samples from 32 patients for antibody to hepatitis-A antigen (anti-HA) by quantitative immune adherence haemagglutination. 12 patients had no detectable anti-HA in either pre-transfusion or late convalescent serum; the other 20 had anti-HA in pretransfusion serum and no significant chance in titre during convalescence. This study excludes H.A.V. as the agent responsible for these cases of post-transfusion hepatitis and supports the existence of "non-A, non-B" hepatitis virus(es).

Antibodies, Viral↗

Multiple hepatitis viruses in multiple attacks of acute viral hepatitis.

We evaluated the causes of 30 episodes of acute viral hepatitis in 13 patients who had multiple attacks. Two (seven per cent) of 30 bouts were caused by hepatitis A virus, and 12 (40%) by hepatitis B virus. No patient, however, had more than one attack with the serologic characteristics of Type A or Type B disease. Thus, there were 16 bouts (53 per cent) not attributable to either of the two recognized hepatitis viruses. None of these "non-A, non-B" episodes, evaluated for infectious mononucleosis and cytomegalovirus infection, could be ascribed to either. From this evidence, therefore, it appears that the clinical syndrome of viral hepatitis is produced not only by the two viruses (hepatitis A virus and hepatitis B virus) recognized since the 1940's but also, in all probability, by two non-A, non-B agents.

Acute Disease↗

Detection of hepatitis A antigen by immunofluorescence.

Hepatitis A antigen (HA Ag) was demonstrated by immunofluorescence (IF) in liver biopsies from chimpanzees with experimental hepatitis A virus infection. Blocking experiments with paired sera from patients with hepatitis types A, B, or non-A, non-B, as well as with purified HA Ag, showed that the fluorescence was specific for HA Ag. HA Ag could be demonstrated only in biopsies from chimpanzees inoculated with hepatitis A virus. In two of four chimpanzees biopsied weekly, HA Ag could be detected by IF before stool shedding of HA Ag, elevation in serum alanine aminotransferase (SGPT), or histopathological evidence of liver disease was seen. The HA Ag was detected for 4 to 5 weeks; the last IF-positive biopsy was obtained after SGPT activity had returned to normal. In the two other chimpanzees, HA Ag could be detected only in the biopsy taken at the time of SGPT elevation. In the early IF-positive biopsies, HA Ag was diffusely distributed in the cytoplasm of many cells, but it later accumulated in a focal distribution in the cytoplasm of a few of the hepatocytes and Kupffer cells. This cytoplasmic distribution agrees with previous electron microscopic data.

Alanine Transaminase↗

Transmission of non-A, non-B hepatitis.

In studies conducted in the early 1950s, sera from six asymptomatic blood donors, implicated in the transmission of viral hepatitis, were inoculated into 10 to 20 volunteers each. Five of these "implicated" donor sera transmitted clinically apparent hepatitis to the recipients. The stored serum samples from these studies have been reanalyzed using serologic markers for hepatitis B virus and hepatitis A virus infection. Two of the donor sera were hepatitis B surface antigen (HBsAg)-positive, and both transmitted hepatitis B virus infection to all susceptible recipients, half of whom showing clinical symptoms. The remaining three infectious donors were HBs-Ag-negative, yet were icterogenic to 10% to 47% of recipients. Testing of serum samples from these recipients with hepatitis showed no evidence of hepatitis B virus or hepatitis A virus infection. This study and other recent evidence suggest that there is a third type of human viral hepatitis--non-A, non-B hepatitis--which is due to a transmissible agent and may well be associated with a chronic carrier state.

Adult↗

Clinical and serological analysis of transfusion-associated hepatitis.

Of 108 prospectively followed, multiply transfused, open-heart-surgery patients, 12 (11%) developed hepatitis. Patients received only volunteer donor blood tested for hepatitis-B surface antigen (HBsAg) prior to transfusion by counterelectrophoresis (C.E.P.). 4 of the 12 patients developed hepatitis-B-virus infection. Subsequent testing of donor serums by solid-phase radioimmunoassay (R.I.A.) revealed that an R.I.A.-positive, C.E.P.-negative blood unit was transfused to 3 of the 4 type-B hepatitis cases, but to none of the remaining 104 patients; 3 hepatitis-B cases could probably have been prevented by prescreening of donors by solid-phase R.I.A. 8 hepatitis cases were serologically unrelated to the hepatitis-B virus, the hepatitis-A virus, the cytomegalovirus, or the Epstein-Barr virus. Had R.I.A.-positive donors been excluded, 8 of the 9 residual hepatitis cases (89%) would have represented "non-A, non-B" hepatitis. The existence of previously unrecognised human hepatitis virus(es) is probable.

Adult↗

Transfusion-associated hepatitis not due to viral hepatitis type A or B.

Twenty-two patients who had an episode of transfusion-associated hepatitis not positive for hepatitis B antigen were examined for development of antibody to heaptitis A and B antigens, cytomegalovirus and Epstein-Barr virus. Antibody response to the 27-nm virus-like hepatitis A antigen was measured by immune electron microscopy. In none of the 22 patients studied did serologic evidence of infection with hepatitis A virus develop during the study period. Nine of the 22 patients had antibody responses to cytomegalovirus, but it was difficult to relate these seroconversions to their hepatitis. In addition, all 22 patients had pre-existing antibody to the Epstein-Barr virus. It seems likely that at least a proportion of such antigen-negative transfusion-associated hepatitis is caused by other infectious agents, not yet identified.

Alanine Transaminase↗

Faecal shedding of hepatitis-A antigen.

Serial stool specimens from two individuals with experimental hepatitis-A infection were examined and the shedding pattern of hepatitis-A antigen (HAAg) was determined by immune electron microscopy. HAAg particles were detected at least 5 days before the development of abnormal transaminase levels and jaundice, but not later than the day of peak transaminase levels. The pattern of early faecal shedding of HAAg particles correlated well with the early infectivity of faeces and accorded with the suggestion that HAAg is involved in the aetiology of hepatitis-A infection.

Alanine Transaminase↗

Experimental infection of chimpanzees with hepatitis A virus.

The susceptibility of chimpanzees to viral hepatitis type A was examined with immine electron microscopy. Of four seronegative infant chimpanzees, two were inoculated with a hepatitis A acute-phase stool filtrate rich in 27 nm virus-like hepatitis A antigen (HA Ag) particles, and two were inoculated with an HA Ag-negative preinfection stool filtrate. One of each pair of chimpanzees was inoculated intravenously, the other orally. One month later both chimpanzees that had received the HA Ag-positive filtrate developed biochemical, histologic, and clinical evidence of acute viral hepatitis. HA Ag particle (27 nm) were detected in their stools by immune electron microscopy; particle shedding followed a pattern similar to that in human volunteers. Immune electron microscopy also showed that antibody HA Ag had developed in the convalescent-phase sera of the infected chimpanzees. Control animals remained free of illness at this time but did develop hepatitis three to five weeks after exposure to the two infected chimpanzee-. The infectious inoculum was titrated in two additional seronegative chimpanzees. It was concluded that hepatitis a can be successfully transmitted to seronegative chimpanzees. Moreover, these studies provide further evidence that the 27-nm virus-like HA Ag particle is the etiologic agent of viral hepatitis type A.

Animals↗

Buoyant density of the hepatitis A virus-like particle in cesium chloride.

We recently visualized by immune electron microscopy a virus-like particle in the stools of patients with hepatitis A. The particle measured approximately 27 nm in diameter and morphologically resembled a picornavirus or parvovirus. To further characterize this particle, we have determined its buoyant density in cesium chloride (CsCl) by ultracentrifugation. Hepatitis A particles from three positive stool specimens were isopycnically banded in separate experiments, and the gradient fractions were examined for particles by immune electron microscopy by using hepatitis A convalescent sera. In each experiment, the particles were observed in a normal distribution about a peak fraction with a mean density of approximately 1.4 g/cm(3). The buoyant density of 1.4 g/cm(3) in CsCl together with its morphology and the reported resistance of hepatitis virus to acid, ether, and heat suggest that this particle is parvovirus-like.

Centrifugation, Density Gradient↗

Cytoplasmic tubular structures in liver of HBsAg carrier chimpanzees infected with delta agent and comparison with cytoplasmic structures in non-A, non-B hepatitis.

Electron microscopic observations were carried out on five HBsAg carrier chimpanzees infected with delta (delta) agent and two chimpanzees infected with human non-A, non-B hepatitis. The cytoplasmic tubular structures, which have been recognized in the liver of chimpanzees infected with human non-A, non-B hepatitis, were found also in the liver of HBsAg carrier chimpanzees infected with delta agent. The quantity of the cytoplasmic structures in serial studies was associated with SGPT elevation rather than with expression of delta antigen in sera and liver tissues. This indicates that the cytoplasmic structures reflect a pathologic change of the hepatocytes in chimpanzees infected with delta agent or human non-A, non-B hepatitis. These and other similarities between the two agents suggest a similar nature.

Animals↗

Rheumatoid factor-like reactants in sera proven to transmit non-A, non-B hepatitis: a potential source of false-positive reactions in non-A, non-B assays.

Convalescent phase non-A, non-B (NANB) human and chimpanzee sera were utilized in a solid-phase radioimmunoassay (RIA) in an attempt to identify a specific NANB antigen in human plasma, plasma-derived pellets and NP-40 disrupted pellets proven to transmit NANB infection to chimpanzees. RIA reactivity was noted in 5 of 8 pedigreed NANB infectious plasmas, but did not appear to be virus-specific. The RIA reactive fraction: (i) had a density of 1.27 to 1.32 gm per cm3 in cesium chloride; (ii) showed immunoreactivity corresponding to normal IgM, but peak RIA activity coincided with an aberrant IgM having a peak sedimentation coefficient of 56 S, and (iii) eluted at higher pH (5.6 to 5.0) than normal IgM on chromatofocusing columns. The reactant shared properties with rheumatoid factor in that it was absorbed by aggregated IgG and was unstable to 2-mercaptoethanol, but it did not react in standard agglutination tests for rheumatoid factor. The reactant was detected in both the acute and chronic phase of NANB infections in chimpanzee and man. By reacting with IgG in presumptive NANB convalescent sera, this aberrant rheumatoid factor could simulate a NANB antigen and represent a cause of false-positive reactions in putative NANB assays.

Animals↗

Further studies by immunofluorescence of the monoclonal antibodies associated with experimental non-A, non-B hepatitis in chimpanzees and their relation to D hepatitis.

To further investigate the specificity of the monoclonal antibodies (48-1 and S-1) associated with non-A, non-B hepatitis, extensive immunofluorescence studies were performed on liver biopsy specimens from chimpanzees with experimental hepatitis A, B, non-A, non-B or delta, or from normal chimpanzees. Both 48-1 and S-1 antibodies reacted in the same manner with liver biopsy specimens from 47 of 50 (94%) chimpanzees with acute or chronic non-A, non-B hepatitis and 15 of 18 (83%) chimpanzees with type D hepatitis. Examinations of serial liver biopsy specimens revealed that the duration of expression of the antigen reacting with the antibodies in hepatocytes of chimpanzees infected with non-A, non-B viruses appeared to be longer than that of chimpanzees infected with the hepatitis delta-virus. By thin-section electron microscopy, the presence of the microtubular aggregates, identical to those previously described for chimpanzees with non-A, non-B hepatitis and shown by immunoelectron microscopy to react with the antibodies, was noted in hepatocytes during the acute phase of hepatitis delta-virus. The antibodies did not react with liver biopsy specimens from chimpanzees acutely or chronically infected with hepatitis B virus or hepatitis A virus, or from normal chimpanzees. The present results confirm our previous observations with the 48-1 and S-1 antibodies. Furthermore, the finding that these two antibodies were also associated with hepatitis D would support the possibility that non-A, non-B agents and the hepatitis delta-virus may have a similar nature or may elicit a similar host response.

Animals↗