A Simple Antigen-Reduction Assay for the Measurement of Neutralizing Antibodies to Hepatitis A Virus

1991 ◽  
Vol 163 (3) ◽  
pp. 634-637 ◽  
Author(s):  
D. L. Krah ◽  
R. D. Amin ◽  
D. R. Nalin ◽  
P. J. Provost
mBio ◽  
2016 ◽  
Vol 7 (6) ◽  
Author(s):  
Asuka Hirai-Yuki ◽  
Lucinda Hensley ◽  
Jason K. Whitmire ◽  
Stanley M. Lemon

ABSTRACTHepatitis A virus (HAV) is an unusual picornavirus that is released from cells cloaked in host-derived membranes. These quasi-enveloped virions (eHAV) are the only particle type circulating in blood during infection, whereas only nonenveloped virions are shed in feces. The reason for this is uncertain. Hepatocytes, the only cell type known to support HAV replicationin vivo, are highly polarized epithelial cells with basolateral membranes facing onto hepatic (blood) sinusoids and apical membranes abutting biliary canaliculi from which bile is secreted to the gut. To assess whether eHAV and nonenveloped virus egress from cells via vectorially distinct pathways, we studied infected polarized cultures of Caco-2 and HepG2-N6 cells. Most (>99%) progeny virions were released apically from Caco-2 cells, whereas basolateral (64%) versus apical (36%) release was more balanced with HepG2-N6 cells. Both apically and basolaterally released virions were predominantly enveloped, with no suggestion of differential vectorial release of eHAV versus naked virions. Basolateral to apical transcytosis of either particle type was minimal (<0.02%/h) in HepG2-N6 cells, arguing against this as a mechanism for differences in membrane envelopment of serum versus fecal virus. High concentrations of human bile acids converted eHAV to nonenveloped virions, whereas virus present in bile from HAV-infectedIfnar1−/−Ifngr1−/−andMavs−/−mice banded over a range of densities extending from that of eHAV to that of nonenveloped virions. We conclude that nonenveloped virions shed in feces are derived from eHAV released across the canalicular membrane and stripped of membranes by the detergent action of bile acids within the proximal biliary canaliculus.IMPORTANCEHAV is a hepatotropic, fecally/orally transmitted picornavirus that can cause severe hepatitis in humans. Recent work reveals that it has an unusual life cycle. Virus is found in cell culture supernatant fluids in two mature, infectious forms: one wrapped in membranes (quasi-enveloped) and another that is nonenveloped. Membrane-wrapped virions circulate in blood during acute infection and are resistant to neutralizing antibodies, likely facilitating HAV dissemination within the liver. On the other hand, virus shed in feces is nonenveloped and highly stable, facilitating epidemic spread and transmission to naive hosts. Factors controlling the biogenesis of these two distinct forms of the virus in infected humans are not understood. Here we characterize vectorial release of quasi-enveloped virions from polarized epithelial cell cultures and provide evidence that bile acids strip membranes from eHAV following its secretion into the biliary tract. These results enhance our understanding of the life cycle of this unusual picornavirus.


2000 ◽  
Vol 74 (23) ◽  
pp. 10950-10957 ◽  
Author(s):  
Andreas Dotzauer ◽  
Ulrike Gebhardt ◽  
Karen Bieback ◽  
Ulrich Göttke ◽  
Anja Kracke ◽  
...  

ABSTRACT The mechanisms underlying the hepatotropism of hepatitis A virus (HAV) and the relapsing courses of HAV infections are unknown. In this report, we show for a mouse hepatocyte model that HAV-specific immunoglobulin A (IgA) mediates infection of hepatocytes with HAV via the asialoglycoprotein receptor, which binds and internalizes IgA molecules. Proof of HAV infection was obtained by detection of HAV minus-strand RNA, which is indicative for virus replication, and quantification of infectious virions. We demonstrate that human hepatocytes also ingest HAV–anti-HAV IgA complexes by the same mechanism, resulting in infection of the cells, by using the HepG2 cell line and primary hepatocytes. The relevance of this surrogate receptor mechanism in HAV pathogenesis lies in the fact that HAV, IgA, and antigen-IgA complexes use the same pathway within the organism, leading from the gastrointestinal tract to the liver via blood and back to the gastrointestinal tract via bile fluid. Therefore, HAV-specific IgA antibodies produced by gastrointestinal mucosa-associated lymphoid tissue may serve as carrier and targeting molecules, enabling and supporting HAV infection of IgA receptor-positive hepatocytes and, in the case of relapsing courses, allowing reinfection of the liver in the presence of otherwise neutralizing antibodies, resulting in exacerbation of liver disease.


2009 ◽  
Vol 58 (11) ◽  
pp. 1433-1436 ◽  
Author(s):  
Ali Azizi ◽  
Danylo Sirskyj ◽  
Richard Weltzin ◽  
David E. Anderson ◽  
Francisco Diaz-Mitoma

The slow growth of hepatitis A virus (HAV) in cell culture is one of the primary pitfalls in the development of sensitive and rapid methods for the detection and quantification of HAV and associated neutralizing antibodies. Currently, in vitro assays frequently require 8 days or more to detect and quantify the presence of HAV neutralizing antibodies. This study describes a rapid immunoassay that allowed the detection of anti-HAV neutralizing antibodies in only 3 days. This microplate-based enzymic assay may be applicable in virological diagnostics, in evaluating the immunogenicity of HAV vaccines and in quantifying neutralizing antibodies during the course of HAV infection.


Author(s):  
L. Yu. Ilchenko ◽  
I. G. Fedorov ◽  
G. G. Totolyan ◽  
A. M. Karelina ◽  
G. A. Sedova ◽  
...  

The article presents clinical case of the jaundice development and severe hyperenzymemia in GAM-Covid-VAK (Sputnik V) vaccination against COVID-19 in a 69-year-old patient. History — systematic use of non-steroidal anti-inflammatory drugs due to persisting pain after knee arthroplasty in 2018; frequent trips for several years to another region for sanatorium treatment, the use of mineral water. The diseases caused by hepatitis viruses, drug damage and post-vaccination reaction were included in diagnostic search. The markers of hepatitis B and C infection viruses were not detected during the enzyme immunoassay and polymerase chain reaction. The indicator for determining the relationship of a drug with the liver damage development was 6 points (borderline value) and only indicated the likelihood of drug hepatotoxicity. At the same time, it is known from history that repeated administration of the drug did not cause liver dysfunctions. The diagnosis of coronavirus infection was established based on the identification of SARS-CoV-2 in the hospital with repeated laboratory testing and competing diagnosis of hepatitis A has been confirmed on the basis of hepatocellular damage and the presence of serological marker of hepatitis A virus (immunoglobulin M antibodies). The treatment was continued in the infectious hospital, where the diagnosis of co-infection was confirmed. The pneumofibrotic changes in the S5 region of the left lung were revealed according to computed tomography. The normalization of aminotransferase activity and bilirubin was noted during dynamic observation. Apparently HAV infection led to a decrease in the immune response, the formation of an insufficient level of neutralizing antibodies in vaccinated against COVID-19 patient M. and contributed to the development of a new coronavirus infection with minimal manifestations in contact with SARS-CoV-2.


2021 ◽  
Vol 12 ◽  
Author(s):  
Fuchun Yang ◽  
Peng Liu ◽  
Xiaohan Li ◽  
Rui Liu ◽  
Li Gao ◽  
...  

Duck enteritis virus (DEV) and duck hepatitis A virus (DHAV) are prevalent duck pathogens, causing significant economic losses in the duck industry annually. Using a fosmid-based rescue system, we generated two DEV recombinants, rDEV-UL26/27-P13C and rDEV-US7/8-P13C, in which the P1 and 3C genes from DHAV type 3 (DHAV-3) were inserted into the DEV genome between genes UL26 and UL27 or genes US7 and US8. We inserted a self-cleaving 2A-element between P1 and 3C, allowing the production of both proteins from a single open reading frame. P1 and 3C were simultaneously expressed in infected chicken embryo fibroblasts, with no difference in growth kinetics between cells infected with the recombinant viruses and those infected with the parent DEV. Both recombinant viruses induced neutralizing antibodies against DHAV-3 and DEV in ducks. A single dose of the recombinant viruses induced solid protection against lethal DEV challenge and completely prevented DHAV-3 infection as early as 7 days post-vaccination. These recombinant P1- and 3C-expressing DEVs provide potential bivalent vaccines against DEV and DHAV-3 infection in ducks.


1998 ◽  
Vol 36 (7) ◽  
pp. 2014-2018 ◽  
Author(s):  
F. D. LaBrecque ◽  
D. R. LaBrecque ◽  
D. Klinzman ◽  
S. Perlman ◽  
J. B. Cederna ◽  
...  

Hepatitis A virus (HAV) immunoassays use cell culture-derived HAV antigen to detect HAV-specific antibodies. The current method of production of HAV antigen in tissue culture is time-consuming and expensive. We previously expressed the HAV open reading frame in recombinant vaccinia viruses (rV-ORF). The recombinant HAV polyprotein was accurately processed and was assembled into subviral particles. These particles were bound by HAV-neutralizing antibodies and were able to elicit antibodies which were detected by commercial immunoassays. The present investigation compared the production of HAV antigen by standard tissue culture methods to the production of HAV antigen with the recombinant vaccinia virus system. In addition, HAV and rV-ORF antigens were assessed for their utility in diagnostic immunoassays. Serum or plasma samples from HAV antibody-positive and antibody-negative individuals were evaluated by immunoassay that used either HAV or rV-ORF antigen. All samples (86 of 86) in which HAV antibody was detected by a commercial enzyme-linked immunosorbent assay (ELISA) also tested positive by the recombinant antigen-based immunoassay (VacRIA). Similarly, all samples (50 of 50) that were HAV antibody negative also tested negative by the VacRIA. The lower limit of detection of HAV antibody was similar among immunoassays with either HAV or rV-ORF antigen. Thus, in the population studied, the sensitivity and specificity of the VacRIA were equivalent to those of the commercial ELISA. Since production of recombinant antigen is faster and less expensive than production of traditional HAV antigen, the development of diagnostic HAV antibody tests with recombinant HAV antigen appears warranted.


Author(s):  
Charles D. Humphrey ◽  
E. H. Cook ◽  
Karen A. McCaustland ◽  
Daniel W. Bradley

Enterically transmitted non-A, non-B hepatitis (ET-NANBH) is a type of hepatitis which is increasingly becoming a significant world health concern. As with hepatitis A virus (HAV), spread is by the fecal-oral mode of transmission. Until recently, the etiologic agent had not been isolated and identified. We have succeeded in the isolation and preliminary characterization of this virus and demonstrating that this agent can cause hepatic disease and seroconversion in experimental primates. Our characterization of this virus was facilitated by immune (IEM) and solid phase immune electron microscopic (SPIEM) methodologies.Many immune electron microscopy methodologies have been used for morphological identification and characterization of viruses. We have previously reported a highly effective solid phase immune electron microscopy procedure which facilitated identification of hepatitis A virus (HAV) in crude cell culture extracts. More recently we have reported utilization of the method for identification of an etiologic agent responsible for (ET-NANBH).


Author(s):  
D.R. Jackson ◽  
J.H. Hoofnagle ◽  
A.N. Schulman ◽  
J.L. Dienstag ◽  
R.H. Purcell ◽  
...  

Using immune electron microscopy Feinstone et. al. demonstrated the presence of a 27 nm virus-like particle in acute-phase stools of patients with viral hepatitis, type A, These hepatitis A antigen (HA Ag) particles were aggregated by convalescent serum from patients with type A hepatitis but not by pre-infection serum. Subsequently Dienstag et. al. and Maynard et. al. produced acute hepatitis in chimpanzees by inoculation with human stool containing HA Ag. During the early acute disease, virus like particles antigenically, morphologically and biophysically identical to the human HA Ag particle were found in chimpanzee stool. Recently Hilleman et. al. have described similar particles in liver and serum of marmosets infected with hepatitis A virus (HAV). We have investigated liver, bile and stool from chimpanzees and marmosets experimentally infected with HAV. In an initial study, a chimpanzee (no.785) inoculated with HA Ag-containing stool developed elevated liver enzymes 21 days after exposure.


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