Evaluation of hepatitis A virus recombinant proteins for detecting anti-HAV IgM and IgG antibodies

ABSTRACT Hepatitis A virus (HAV) is a major causative agent of self-limiting liver infections. India was highly endemic for HAV in the past; children were exposed to the virus at an early age without any disease symptoms and developed lifelong immunity. With improvements in living conditions, an epi...

Full description

Saved in:
Bibliographic Details
Main Authors: Supriya Hunderkar, Nital Ganorkar, Atul Walimbe, Kavita Lole
Format: Article
Language:English
Published: American Society for Microbiology 2025-04-01
Series:Microbiology Spectrum
Subjects:
Online Access:https://journals.asm.org/doi/10.1128/spectrum.01528-24
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1849737658093273088
author Supriya Hunderkar
Nital Ganorkar
Atul Walimbe
Kavita Lole
author_facet Supriya Hunderkar
Nital Ganorkar
Atul Walimbe
Kavita Lole
author_sort Supriya Hunderkar
collection DOAJ
description ABSTRACT Hepatitis A virus (HAV) is a major causative agent of self-limiting liver infections. India was highly endemic for HAV in the past; children were exposed to the virus at an early age without any disease symptoms and developed lifelong immunity. With improvements in living conditions, an epidemiological transition is occurring. There is a significant increase in hepatitis A outbreaks involving adolescents and young adults. The gold standard for hepatitis A diagnosis is anti-HAV IgM antibodies. Although antibody responses are primarily targeted against HAV structural proteins (capsid proteins), non-structural proteins are also immunogenic. In the present study, we expressed HAV capsid proteins VP1-2A, VP0 (VP4 + VP2), VP3, and non-structural protein 3CPro in the bacterial system and explored the possible use of these as antigens to detect anti-HAV IgM and IgG antibodies using a well-defined serum sample panel. The capsid protein-based assays showed overall less sensitivity for detection of both anti-HAV IgM and IgG antibodies as compared to whole virus antigen-based commercial assays. Among capsid proteins, rVP1-2A showed the highest sensitivity (86.3%) and specificity (84.2%) in detecting anti-HAV IgG, while rVP0 (VP2 + VP4) exhibited the highest sensitivity (79.5%) and specificity (80.2%) for IgM antibodies. Interestingly, r3CPro exhibited higher sensitivity (96.9%) and specificity (93.2%) in IgM detection and 93.94% sensitivity and 88% specificity for IgG, indicating its usefulness in detecting both anti-HAV IgM and IgG antibodies during the acute phase of the disease. Though 3CPro appeared to be useful in differentiating antibody responses due to infection and vaccination, our analysis revealed that the anti-3CPro antibody response is short-lived after natural infection, and hence, it cannot be used as a marker to differentiate between infection and vaccination. However, 3CPro would be useful for developing a hepatitis A diagnostic assay.IMPORTANCEHepatitis A was highly endemic in India earlier. With recent developments, there is a shift in the endemicity to intermediate levels. This has resulted in the occurrence of hepatitis outbreaks with symptomatic infections in adolescents and adults. Occasionally, the disease manifestations are serious, leading to acute liver failure. In such a situation, there is a need for a timely diagnosis of the infection.
format Article
id doaj-art-97812eecba6c4e9ea04c9b7404c91232
institution DOAJ
issn 2165-0497
language English
publishDate 2025-04-01
publisher American Society for Microbiology
record_format Article
series Microbiology Spectrum
spelling doaj-art-97812eecba6c4e9ea04c9b7404c912322025-08-20T03:06:51ZengAmerican Society for MicrobiologyMicrobiology Spectrum2165-04972025-04-0113410.1128/spectrum.01528-24Evaluation of hepatitis A virus recombinant proteins for detecting anti-HAV IgM and IgG antibodiesSupriya Hunderkar0Nital Ganorkar1Atul Walimbe2Kavita Lole3ICMR-National Institute of Virology, Pune, Maharashtra, IndiaICMR-National Institute of Virology, Pune, Maharashtra, IndiaICMR-National Institute of Virology, Pune, Maharashtra, IndiaICMR-National Institute of Virology, Pune, Maharashtra, IndiaABSTRACT Hepatitis A virus (HAV) is a major causative agent of self-limiting liver infections. India was highly endemic for HAV in the past; children were exposed to the virus at an early age without any disease symptoms and developed lifelong immunity. With improvements in living conditions, an epidemiological transition is occurring. There is a significant increase in hepatitis A outbreaks involving adolescents and young adults. The gold standard for hepatitis A diagnosis is anti-HAV IgM antibodies. Although antibody responses are primarily targeted against HAV structural proteins (capsid proteins), non-structural proteins are also immunogenic. In the present study, we expressed HAV capsid proteins VP1-2A, VP0 (VP4 + VP2), VP3, and non-structural protein 3CPro in the bacterial system and explored the possible use of these as antigens to detect anti-HAV IgM and IgG antibodies using a well-defined serum sample panel. The capsid protein-based assays showed overall less sensitivity for detection of both anti-HAV IgM and IgG antibodies as compared to whole virus antigen-based commercial assays. Among capsid proteins, rVP1-2A showed the highest sensitivity (86.3%) and specificity (84.2%) in detecting anti-HAV IgG, while rVP0 (VP2 + VP4) exhibited the highest sensitivity (79.5%) and specificity (80.2%) for IgM antibodies. Interestingly, r3CPro exhibited higher sensitivity (96.9%) and specificity (93.2%) in IgM detection and 93.94% sensitivity and 88% specificity for IgG, indicating its usefulness in detecting both anti-HAV IgM and IgG antibodies during the acute phase of the disease. Though 3CPro appeared to be useful in differentiating antibody responses due to infection and vaccination, our analysis revealed that the anti-3CPro antibody response is short-lived after natural infection, and hence, it cannot be used as a marker to differentiate between infection and vaccination. However, 3CPro would be useful for developing a hepatitis A diagnostic assay.IMPORTANCEHepatitis A was highly endemic in India earlier. With recent developments, there is a shift in the endemicity to intermediate levels. This has resulted in the occurrence of hepatitis outbreaks with symptomatic infections in adolescents and adults. Occasionally, the disease manifestations are serious, leading to acute liver failure. In such a situation, there is a need for a timely diagnosis of the infection.https://journals.asm.org/doi/10.1128/spectrum.01528-24hepatitis A virusdiagnosisELISAcapsid proteinsnon-structural proteinsviral protease
spellingShingle Supriya Hunderkar
Nital Ganorkar
Atul Walimbe
Kavita Lole
Evaluation of hepatitis A virus recombinant proteins for detecting anti-HAV IgM and IgG antibodies
Microbiology Spectrum
hepatitis A virus
diagnosis
ELISA
capsid proteins
non-structural proteins
viral protease
title Evaluation of hepatitis A virus recombinant proteins for detecting anti-HAV IgM and IgG antibodies
title_full Evaluation of hepatitis A virus recombinant proteins for detecting anti-HAV IgM and IgG antibodies
title_fullStr Evaluation of hepatitis A virus recombinant proteins for detecting anti-HAV IgM and IgG antibodies
title_full_unstemmed Evaluation of hepatitis A virus recombinant proteins for detecting anti-HAV IgM and IgG antibodies
title_short Evaluation of hepatitis A virus recombinant proteins for detecting anti-HAV IgM and IgG antibodies
title_sort evaluation of hepatitis a virus recombinant proteins for detecting anti hav igm and igg antibodies
topic hepatitis A virus
diagnosis
ELISA
capsid proteins
non-structural proteins
viral protease
url https://journals.asm.org/doi/10.1128/spectrum.01528-24
work_keys_str_mv AT supriyahunderkar evaluationofhepatitisavirusrecombinantproteinsfordetectingantihavigmandiggantibodies
AT nitalganorkar evaluationofhepatitisavirusrecombinantproteinsfordetectingantihavigmandiggantibodies
AT atulwalimbe evaluationofhepatitisavirusrecombinantproteinsfordetectingantihavigmandiggantibodies
AT kavitalole evaluationofhepatitisavirusrecombinantproteinsfordetectingantihavigmandiggantibodies