Radioimmunoassay detection of igm antibodies to the hbv‐associated delta (δ) antigen: Clinical significance in δ infection

Abstract

A sensitive radioimmunoassay was developed for specific detection of IgM antibodies to the hepatitis b virus-associated delta antigen. The test is based on the selective absorption of IgM by anti-IgM fixed on a solid phase. Transient primary IgM anti-delta responses with no conversion to a secondary IgG response were observed in acute self-limited delta infection. IgM anti-delta was invariably found in hepatitis B surface antigen (HBsAg) carriers with active delta infection and liver disease, while it was absent in HBsAg-positive or negative individuals with anti-delta of IgG class but without liver damage or intrahepatic delta antigen. IgM anti-delta appears useful in defining the epidemiology of acute delta infection and in the serological diagnosis of active delta disease from nonpathogenic or past delta infection.

Pegylated interferon alpha-2b as monotherapy or in combination with ribavirin in chronic hepatitis delta

“…IgM anti-HD was measured using a previously described capture immunoassay. 16 Serum samples were tested for HDV RNA as previously reported 17 by semiquantitative single and nested polymerase chain reaction (PCR) assays, with a sensitivity of approximately 1,000 and 1-10 genomes/mL respectively. Serum HBV DNA levels were determined with a commercial quantitative PCR assay (Amplicor HBV Monitor Test, Roche Diagnostics, GmbH Mannheim, Germany) with a sensitivity threshold of about 400 copies/mL.…”

Delta hepatitis: molecular biology and clinical and epidemiological features

“…Most studies have indicated that HBV carriers superinfected with HDV generally develop and maintain serologic markers that indicate ongoing viral replication, including high titers of anti-HD and persistence of IgM anti-HD, serum HDV RNA, and intrahepatic HDAg (22,64,187,188,190). However, this is not always the case, and patients may lose detectable HBsAg secondary to HDV suppression of HBV replication (46,91,110,135).…”

“…However, the diagnosis rests on finding HDAg in the liver or, in those patients with active viral replication, finding HDV RNA in serum (64,188,190).…”

“…The appearance of HDAg, however, is not detected until after HBsAg begins to circulate as a marker of HBV infection. Coinfection often results in the transient existence of anti-HD, which is generally of relatively low titer and often of immunoglobulin M (IgM) anti-HD specificity (188).…”

Design and Construction of Chimeric VP8-S2 Antigen for Bovine Rotavirus and Bovine Coronavirus

“…38 Linkers play an important role in displaying the epitopes on surface of fusion proteins. 39 We used Glycine and Serine (GS 4 ) 3 residues from flexible linkers that could separate different domains in chimeric proteins and they have sufficient flexibility that may enhance protein expression level. 40 Then chimeric VP8-S2 gene was constructed, it was cloned and sub-cloned into pGH and pET32a(+), respectively.…”