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Biomedical subjects

L Vitvitski

Publications and source records attributed to L Vitvitski.

72 records · Page 4Linked to original sources
PubMed1981

Non-A, Non-B hepatitis virus: identification of a core antigen-antibody system that cross reacts with hepatitis B core antigen and antibody.

Using immunodiffusion, a major cross-reactivity had been previously demonstrated between hepatitis B(HBe/3 Ag) and the antigen reported in the serum on non A, non-B hepatitis patients, therefore redesignated NANBe Ag. By direct immunofluorescence a new antigen associated with, but distinct from, NANBe Ag has now been identified in the liver of 14/26 patients with NANB chronic active hepatitis. The homologous antibody was detected in the serum of these 14 patients. Behaving like HBc Ag and cross reacting with it by immunofluorescence, the new antigen was termed NANBc Ag. Anti NANBc also became detectable in serial acute phase and convalescence sera from 5/5 NANB Ag-positive posttransfusion hepatitis cases. Further characterization of NANBe and NANBc antigens achieved by fractionation of a NANB virus-infected liver showed NANBc Ag to be expressed on 22-25 nm HB core-like particles containing DNA polymerase activity. Cross-reactivity between NANBc and HBc antigens was confirmed by immunodiffusion. Liver-derived NANBe Ag identical to serum NANBe Ag exhibited the same physical properties as HBe/3 Ag and could be similarly released by disruption of the non-A, non-B, virus cores. These results indicate that hepatitis B and NANB virions not only share the same structure and DNA polymerase activity but are also antigenically related and belong to the same new class of DNA viruses.

Antibodies, Viral↗
PubMed1981

Detection by immunofluorescence of a new "core-like" Ag/Ab system in liver and serum of patients with NANB hepatitis.

Using direct immunofluorescence, a nuclear antigen was found in liver of chronic hepatitis patients with circulating NANBe Ag or anti-NANBe, and selected sera from either group were used as source of conjugates. The new Ag/Ab system was designated NANBc Ag and anti-NANBc since it behaved like the core Ag of HBV . NANBc Ag was detected in coded frozen liver biopsies from patients with chronic persistent 15/25 (60%) or active 27/50 (54%) hepatitis and cryptogenic cirrhosis 16/30 (53.3%) devoid of HBV markers. Only 2/30 alcoholic cirrhosis cases (7%) used as controls were positive (p less than or equal to 0.001). The homologous anti-NANBc antibody was always detectable by indirect immunofluorescence in the patients' serum when NANBc Ag was found in the liver. It was also found in 11/135 (8%) additional cases without any other NANB marker. A correlation was observed between coded detection of the NANBc Ag/Ab system by immunofluorescence and demonstration of NANBe Ag or anti-NANBe by immunodiffusion. In acute post-transfusion NANB hepatitis, anti-NANBc was first detectable 14 days after transfusion and persisted as long as ALT remained elevated, or longer. IgM anti-NANBc present at onset became associated with an increasing proportion of IgG after the 28th day. The prevalence of anti-NANBc in sporadic NANB hepatitis (11/50 = 22%) was significantly lower (p less than or equal to 0.001) than in cases with parenteral exposure such as post-transfusion, occupational or drug addict hepatitis (47/72 = 65%). Immunofluorescent tests for NANBc Ag and Ab are promising assays for the serological diagnosis of NANB hepatitis.

Antibodies, Viral↗
PubMed1980

[Non-A non-B hepatitis virus: demonstration of a double antigenic and structural kinship with hepatitis B virus].

Major antigenic identity has been demonstrated by immunodiffusion between the Ag described by Shirachi and confirmed by us (NANB/e) in the serum on non A non B hepatitis and the HBe/3 specificity of hepatitis B virus (HBV). A second Ag (NANB/c) linked to the core of a new virion morphologically similar to HBV and also associated with ADN polymerase activity as recently described, has been identified and purified from an infected liver. This NANB/c Ag also cross reacts with HBc Ag. These results confirm that HBV and the NANB virus defined here belong to the same new class of DNA viruses.

Animals↗
PubMed1980

Two low molecular weight peptides as common determinants to different molecular forms and specificities of hepatitis B e antigen (HBeAg).

Two fractions, I and II, corresponding to heavy and light molecular forms of HBeAg and respectively associated with the (HBe/1 + HBe/2) and (HBe/3) specificities, were separated by ammonium sulfate precipitation in HBeAg positive chimpanzee plasma. I 125-labeling of fractions I and II and immune precipitation by anti-HBe and anti-Human IgG were followed by autoradiographic analysis after SDS polyacrylamide gel electrophoresis: This revealed that two small peptides (a major 17,000 MW and minor 21,000 MW) seem common to the various molecular forms and specificities of HBeAg. Both peptides were found tightly linked to IgG in fraction I, associated with HBe/1 and HBe/2 and precipitated by 1.33 M (NH4)2SO4. In the HBe/3-positive fraction II these peptides seemed attached to IgG light chains only.

Electrophoresis, Polyacrylamide Gel↗
PubMed1980

Non-a, non-b hepatitis: identification of hepatitis-B-like virus particles in serum and liver.

Hepatitis B virus-like particles including: small spheres and filaments 15--25 nm in diameter together with a 35--40 nm Dane particle-like virion have been identified in sera of patients with non-A, non-B hepatitis. In a coded serological study, such particles were detected transiently in 3/4 acute, and persistently in 7/8 chronic cases of non-A, non-B hepatitis with non-A, non-B antigenemia. Only 2/12 similar cases without non-A, non-B antigens (Ag) in serum had detectable particles but neither patients with drugs, or type A hepatitis, nor cases of obstructive jaundice. The particles did not express hepatitis B surface (HBs) or non-A, non-B Ag at their surface but were associated, in three patients, with significant endogenous DNA polymerase activity. Furthermore, particles similar to hepatitis B cores (BHc) and also associated with DNA polymerase activity were demonstrated by sucrose gradient ultracentrifugation of a liver homogenate obtained from a patient who had died of non-A, non-B hepatitis. The non-A, non-B hepatitis virion described here appears, therefore, as a hepatitis B-like virus. The exact kinship between these two agents is currently being investigated.

Chromatography, Gel↗
PubMed1980

Use of the cross-reactivity between hepatitis B and non-A, non-B viruses for the identification and detection of non-A, non-B 'e' antigen.

The morphological similarities between B and non-A, non-B hepatitis viruses prompted the search for common antigenic determinants between the two agents. Major antigenic cross-reactivity was demonstrated by immunodiffusion between hepatitis B e/3 and the most common circulating antigen previously reported in the serum of patients with non-A, non-B hepatitis. Since it is the equivalent of an e antigen, this antigen will be hereafter referred to as non-A, non-B/e antigen. Screening with hepatitis B e/3 antigen or anti-hepatitis B e/3 by immunodiffusion may be used as an easy and efficient way to test for non-A, non-B hepatitis in the absence of specific reagents since it detected up to 91% of non-A, non-B antigen and 86% of anti-non-A, non-B/e. Antigenic cross-reactivity may be used to look for additional viruses belonging to the hepatitis B group.

Antibodies, Viral↗
PubMed1980

Identification and detection of long incubation non-A, non-B hepatitis virus and associated antigens or antibodies.

Three distinct antigen/antibody systems supposedly associated with an HBV-like virus of non-A, non-B hepatitis have been identified. Because of previously demonstrated cross-reactivity with HBe/3 and HBc antigens and other analogies the following terminology is tentatively used. 1. The previously reported serum antigen has been redesignated non-A, non-B e antigen, since it is equivalent to HBe/3 Ag and cross-reacts with it. Non-A, non-BeAg or Ab were detected in 51/62 post-transfusion and 11/56 sporadic acute non-A, non-B hepatitis cases, and in 12/14 cases affecting staff members. In non-A, non-B chronic persistent or active hepatitis and cryptogenic cirrhosis, the prevalence was similarly high: 14/18, 22/48 and 12/18 respectively. Ten out of 26 implicated blood donors were found positive for non-A, non-BeAg accounting for 7 out of 8 post-transfusion cases. A high prevalence of non-A, non-BeAg was also found in haemophiliacs (11/48) and haemodialysed patients (6/42), whereas anti-non-A, non-Be was respectively detected in 4/48 and 6/42 of these cases. 2. Using immunofluorescence, a second antigen termed non-A, non-BcAg has been identified in liver biopsies from 55/84 non-A, non-B chronic hepatitis or cryptogenic cirrhosis cases. All 8 positive biopsies examined by electron microscopy revealed clusters of 22--25 nm intranuclear particles identical to those described in chimpanzees. Anti-non-A, non-Bc detectable by counter-electrophoresis and indirect immunofluorescence was found in the serum of all patients of which biopsy was positive for non-A, non-BcAg. Anti-non-A, non-Bc was also detected in 5/5 non-A, non-BeAg positive cases of post-transfusion hepatitis, 2--6 weeks after onset end remained positive for the 6 month follow-up period. 3. A third antigen, tentatively designated non-A, non-BsAg, has been found less frequently than non-A, non-BeAg in serum. However, it was detectable in 3/18 and 2/12 washed ultracentrifugation pellets of sera positive for non-A, non-BeAg or anti-non-A, non-Be, respectively.

Antibodies, Viral↗
PubMed1980

A non-A non-B hepatitis epidemic in a HB antigen-free haemodialysis unit. Demonstration of serological markers of non-A non-B virus.

One hundred and thirty six patients receiving haemodialysis in a HB antigen-free unit were prospectively studied over a period of 29 months for evidence of hepatitis. Twelve/one hundred and eleven patients who were dialysed in this unit for at least one month developed elevation of ALT which proved to be related to neither toxic hepatitis nor hepatitis due to any of the following viruses: hepatitis B virus (HBV), hepatitis A virus (HAV), cytomegalovirus (CMV) or Epstein-Barr virus (EBV). Therefore these cases were considered to be non-A non-B (NANB) hepatitis. In 5 patients the liver disease was of short duration, whereas in 7 others hepatitis had a chronic course with ALT remaining elevated for more than 6 months. During the same period, one/sixty staff members who were working for at least one month in this unit also developed presumed non-A non-B hepatitis. Serological markers of NANB infection tested by double immunodiffusion were present in 10/12 patients and in the one staff member.

Cross Infection↗
PubMed1979

[Identification of a virus similar to hepatitis B virus in non-A non-B hepatitis].

Hepatitis B virus-like particles (including DANE particles) with DNA polymerase activity but negative for HBs Ag have been identified in NON-A, NON-B hepatitis sera positive for HC Ag. Although specifically associated with the particles, HC Ag is not a surface antigen of the hepatitis C virus identified here for the first time. The relationship of this agent with HBV seems obvious, and deserves further study.

Hepatitis B virus↗
PubMed1979

Detection of virus-associated antigen in serum and liver of patients with non-A non-B hepatitis.

In a search for serological markers of non-A non-B(NANB) hepatitis, sera from repeatedly transfused and convalescent patients were assayed by immunodiffusion against sera from 12 patients with early acute NANB hepatitis. A new antigen/antibody system distinct from HBsAg was demonstrated in 8 cases. To assess the specificity of the test, serial sera from 17 patients with acute hepatitis of known aetiology (10 due to hepatitis-B virus, 4 to hepatitis-A virus, 3 to drugs) were tested twice a month, together with sera from 14 NANB patients obtained during a prospective post-transfusion study. NANB antigen (Ag) was detected in at least one sample from 12 of the 14 NANB patients (86%) but in none of the other groups. NANB Ag appeared after or just before elevation of transaminase levels and was cleared before they fell to normal. 4 of 5 patients who showed seroconversion to NANB antibody (Ab) had transient hepatitis. In contrast, the alanine adminotransferase value returned to normal in only 1 of the 5 with persistent NANB antigenaemia during 6 months' follow-up. NANB Ag was also demonstrated by immunodiffusion in liver extracts from patients with chronic NANB hepatitis with antigenaemia. Fluorescein-isothiocyanate-labelled gammaglobulins with strong NANB Ab activity revealed specific nuclear fluorescence in foci of hepatocytes on cryostat sectons of these livers but in none of 6 control human livers. The results suggest that the antigen and antibody are specifically linked to NANB hepatitis of long incubation period.

Acute Disease↗
PubMed1979

[Demonstration of a serum and liver antigen in acute or chronic non A-non B viral hepatitis].

A new precipitating antigen-antibody system possibly was demonstrated by immuno-diffusion in the serum of patients suffering from non A-non B hepatitis. The antigen appears during the first four weeks of transaminases elevation. In acute cases was transient antigenemia (average 3 weeks). Antibodies appeared rapidly after the disappearance of antigen. The same antigen was also detected, by immunodiffusion and by immunofluorescence, in the liver nuclei of infected hepatocytes. This antigen specific appears for non A-non B hepatitis since it is neither found in the serum of normal subjects nor in that of patients with cirrhosis toxic or viral that hepatitis A or B. The hypothesis of a virus associated antigen is the most likely explanation.

Acute Disease↗
PubMedDate not supplied

Transmission of serologically silent hepatitis B virus along with hepatitis C virus in two cases of posttransfusion hepatitis.

The polymerase chain reaction (PCR) was used to investigate the presence of hepatitis B virus (HBV)-related DNA sequences in blood from three blood donors and two transfusion recipients who developed posttransfusion non-A, non-B hepatitis (NANBH). In the first case, the sole donor was positive for antibody to hepatitis B surface (HBs) and core (HBc) antigens and had elevated alanine aminotransferase (ALT) levels, while the recipient had no HBV serologic markers. Both the donor and the recipient had serologic markers of hepatitis C virus (HCV) and were found positive for HBV DNA and HCV RNA sequences by PCR. The second case involved two donors and one recipient. Serologic tests for conventional HBV markers were negative in all three individuals, but one of the donors had elevated ALT. HBV DNA sequences were detected by PCR in the serum of the recipient and of the donor with high ALT, but not in the serum of the donor with normal ALT. Anti-HCV was detected in the serum of the recipient and of the suspect donor but not in that of the donor with normal ALT. The sequences amplified in the S region and determined after cloning of PCR products for both donor-recipient pairs were indistinguishable from each other and identical to the sequence of the major HBV subtype of adw in the first case and ayw in the second case. Furthermore, for the second case, an identical single-point mutation was found in both the donor and the recipient. These data confirm the transmission of conserved HBV sequences together with HCV in posttransfusion NANBH.(ABSTRACT TRUNCATED AT 250 WORDS)

Alanine Transaminase↗
PubMedDate not supplied

[Significance of the expression of pre-S proteins in mononuclear blood cells in chronic hepatitis caused by the hepatitis B virus].

In chronic viral type B hepatitis, the presence in the serum of pre-S proteins of hepatitis B virus (HBV) envelope reflects viral replication. As peripheral blood mononuclear cells (PBMC) are known to be target cells for HBV replication, the aim of our study was to investigate the clinical relevance of pre-S protein expression in PBMC. Fifty-seven patients with chronic type B hepatitis and HBs antigenemia were studied. Following separation using the Ficoll gradient, the PBMC were lysed and studied for pre-S proteins by Western blot. HBs Ag and HBc/e Ag were assayed in parallel by radioimmunoassay. HBs Ag was detected in PBMC in 86 percent of cases, HBc/e Ag in 28 percent of cases and pre-S proteins in 34 percent of cases. A statistically significant association was found between the presence of HBc/e Ag in PBMC and both the serum HBe Ag (chi 2 test, p less than 0.01) and the serum viral DNA/DNA polymerase (t test, p = 2.10(-4)). The pre-S protein expression in PBMC was significantly associated with higher levels of DNA/DNA polymerase activity (chi 2 test, p less than 0.05). The expression of pre-S proteins in PBMC appears therefore to correlate with the HBV viral replication phase. The HBc/e Ag and pre-S protein detection in PBMC therefore offers a reliable non invasive approach to tissular viral replication. The clinical relevance of pre-S testing in PBMC was illustrated by the study of 12 cases of chronic active hepatitis positive for anti-HBe but with no or low level of serum DNA polymerase activity.(ABSTRACT TRUNCATED AT 250 WORDS)

Chronic Disease↗