Apolipoprotein B100 is required for hepatitis C infectivity and Mipomersen inhibits hepatitis C

AIM To characterize the role of apolipoprotein B100(apoB 100) in hepatitis C viral(HCV) infection. METHODS In this study, we utilize a gene editing tool, transcription activator-like effector nucleases(TALENs), to generate human hepatoma cells with a stable genetic deletion of APOB to assess of apoB in HCV. Using infectious cell culture-competent HCV, viral pseudoparticles, replicon models, and lipidomic analysis we determined the contribution of apoB to each step of the viral lifecycle. We further studied the effect of mipomersen, an FDAapproved antisense inhibitor of apoB 100, on HCV using in vitro cell-culture competent HCV and determined itsimpact on viral infectivity with the TCID50 method. RESULTS We found that apo B100 is indispensable for HCV infection. Using the JFH-1 fully infectious cell-culture competent virus in Huh 7 hepatoma cells with TALENmediated gene deletion of apoB(APOB KO), we found a significant reduction in HCV RNA and protein levels following infection. Pseudoparticle and replicon models demonstrated that apo B did not play a role in HCV entry or replication. However, the virus produced by APOB KO cells had significantly diminished infectivity as measured by the TCID-50 method compared to wildtype virus. Lipidomic analysis demonstrated that these virions have a fundamentally altered lipidome, with complete depletion of cholesterol esters. We further demonstrate that inhibition of apoB using mipomersen, an FDA-approved anti-sense oligonucleotide, results in a potent anti-HCV effect and significantly reduces the infectivity of the virus. CONCLUSION Apo B is required for the generation of fully infectious HCV virions, and inhibition of apo B with mipomersen blocks HCV. Targeting lipid metabolic pathways to impair viral infectivity represents a novel host targeted strategy to inhibit HCV.

Targeted tumor coating with antigenic, CTL-recognizable peptides via Annexin A5 chimeric constructs following chemotherapy redirects adaptive CD8+ T cell immunity for tumor clearance

A common drawback of many cancer immunotherapies,including immune checkpoint blockade,is their reliance on the expression of immunogenic tumor antigens by cancer cells for immune recognition and clearance,which limits their efficacy against cancers with weak antigenicity.1 To overcome this obstacle,we and others have explored strategies to harness the immune responses against nontumor antigens and redirect those immune responses to target tumor cells.2,3,4,5 In particular,we have pioneered a therapeutic strategy fusing tumor-targeting proteins with known antigenic peptide epitopes not naturally expressed by tumor cells,which are flanked by peptide sequences that can be recognized and cleaved by proteases overexpressed in most cancers.2,3 This strategy facilitates the targeted delivery of immunogenic peptides into tumor foci,the release of immunogenic peptides into the tumor microenvironment(TME)via tumor protease cleavage,and subsequent loading of these peptides onto major histocompatibility complex class 1(MHC-I)on the tumor cell surface,allowing the recognition of coated tumor cells by the respective peptide-specific cytotoxic CD8+T lymphocytes(CTLs)for elimination.