- 现金
- 62111 元
- 精华
- 26
- 帖子
- 30437
- 注册时间
- 2009-10-5
- 最后登录
- 2022-12-28
|
RS-3403
Viral hepatitis
Hepatitis B & D - Experimental
ANTI CAPSID DRUGS HAP12 AND AT130 TARGET HBV CORE PROTEIN NUCLEAR FUNCTIONS
Laura Belloni1, 2, Gianna Aurora Palumbo2, Leonardo Lupacchini2, Lichun Li3, Srinivas Reddy Chirapu4, Ludovica Calvo2, M G Finn4, Uri Lopatin5, Adam Zlotnick3, 5, Massimo Levrero* 1
1Center for Life Nano Science (CLNS), IIT-Sapienza University, 2Dept of Internal Medicine - DMISM, Sapienza University, Rome, Italy, 3Dept of Molecular & Cellular Biochemistry, Indiana University, Bloomington, 4Dept Chemistry, Georgia Institute of Technology, Atlanta, 5Assembly Bioscience, Bloomington, United States
Corresponding author’s email: [email protected]
Background and Aims:
HBV Core protein (Cp) represents an attractive new therapeutic target for HBV chronic infection. In addition to their role in capsid assembly, pgRNA packaging and reverse transcription, Cp has been shown to bind the nuclear cccDNA mini-chromosome as well as a number of cellular genes promoters. Several compounds that target Cp and HBV capsids assembly, including the Hetero-aryl-dihydropyrimidines (HAPs) and the phenyl-propenamide derivatives AT61 and AT130, have been shown to inhibit HBV replication in vitro and in vivo. HAPs and AT130 enhance the rate and the extent of Cp assembly leading to non-functional capsids and, at high concentration, stabilize preferentially non-capsid polymers of Cp. Here we investigated the ability of the Core protein Assembly Modulators (CaMPs) HAP12 and AT130 to affect both nuclear (cccDNA structure and transcription) and cytoplasmic (capsid maturation and replication) Cp functions as part of their antiviral activity against HBV.
Methods:
HAP12 and AT130 effects on capsid-associated HBV-DNA (TaqMan real-time PCR), cccDNA (TaqMan real-time PCR) and pgRNA levels (quantitative real-time PCR with specific primers), were assessed in: a) HBV-infected NTCP-HepG2 cells; b) AD38 inducible HBV stable cell line. Recruitment of HBc and histone modifications on the viral minichromosome were assessed using the cccDNA ChIP assay in AD38 cells.
Results:
CaMPs treatments started at day 6 post-infection (NTCP-HepG2) or day 6 post-induction (AD38 tet-off cells) resulted in a very strong inhibition of HBV replication (>95%) and a significant but incomplete reduction of the stable cccDNA pool. A strong effect on cccDNA-dependent HBeAg production (AD38 tet-off) and pgRNA transcription (AD38 tet-off / tet-on and NTCP-HepG2 infected cells) was also demonstrated. The ability HAP12 to target cccDNA transcription was confirmed by the reduced cccDNA-bound H3 histone acetylation and the descreased HBc occupancy on the cccDNA in induced AD38 cells. Importantly, when CaMPs treatment was started during infection, cccDNA formation/accumulation was completely inhibited (>95%) and viral replication was blunted.
Conclusions:
Anti-capsid compounds (CpAMs) have an impact on Cp nuclear functions at multiple levels: block of new cccDNA formation / accumulation, reduction of an established cccDNA pool and inhibition of HBc occupancy and histone acetylation on the cccDNA that translate into a reduced pgRNA transcription.
Disclosure of Interest: L. Belloni: Grant: Gilead, G. A. Palumbo: : None Declared, L. Lupacchini: : None Declared, L. Li: : None Declared, S. R. Chirapu: : None Declared, L. Calvo: : None Declared, M. G. Finn: : None Declared, U. Lopatin: Stockholder: Assembly Bioscience, Employee: Assembly Bioscience, A. Zlotnick: Stockholder: Assembly Bioscience, M. Levrero: Consultant: Gilead, BMS, Janssen, Medimmune, Tekmira, Galapagos, Sponsored Lectures (National or International): Gilead, BMS, Janssen, Roche, MSD
|
|