First detected in 1977, Hepatitis Delta virus (HDV) is a major cause of cirrhosis (occurring in ~70-80% of chronic cases) and hepatocellular carcinoma (HCC). At least 12 million people (and possibly significantly more) are chronically infected with both Hepatitis B virus (HBV) and HDV, putting them at increased risk of accelerated liver failure and HCC when compared to those patients carrying only HBV (1, 2). In addition, studies examining the oncogenicity of HDV itself, apart from its replicative dependence on HBV, have demonstrated that HDV-related HCC may be due to a mechanism (i.e., induction of genomic instability) distinct from that driving HBV-HCC (1). More research into HDV biology, HDV pathogenesis, and HDV hepatocarcinogenesis is essential, as the only recommended treatment (with limited success) is an extended course of peginterferon alfa (2).

HDV is a defective virus that can only infect individuals who are also infected with HBV, as it needs HBsAg in its envelope to enter hepatocytes (1, 2). It has the most compact genome known among animal viruses, consisting of a circular single-stranded RNA of perhaps 1.7 KB. The only protein encoded is the hepatitis delta antigen (HDAg), which exists as two isoforms: Large HDAg (L-HDAg (214 a.a.)) and Small HDAg (S-HDAg (195 a.a.)) (1). L-HDAg contains the S-HDAg sequence as well as a C-terminal isoprenylation motif required for linking the HDV ribonucleoprotein to HBsAg during viral particle assembly. S-HDAg is necessary for viral replication, while L-HDAg is inhibitory (1). HDV replicates only in the nucleus of hepatocytes and retasks the host RNA polymerase II to replicate its genome. Thus, HBsAg is the indispensable (and only) component needed from HBV for HDV replication, being crucial for HDV’s ability to infect hepatocytes as well as viral assembly and virion release (1, 2).

GeneTex continues its commitment to producing quality reagents for infectious disease research. For HDV research, GeneTex is proud to introduce new recombinant antibody products against the Large HDAg isoform (Hepatitis D virus Large delta protein antibody [HL1051] (GTX636026)) and both the Large and Small HDAg isoforms (Hepatitis D virus Large delta + Small delta protein antibody [HL1053] (GTX636028) and Hepatitis D virus Large delta + Small delta protein antibody [HL1055] (GTX636030)) to expand its catalog. Please see the highlighted product images below for more details.