HBV genes induce cytotoxic T‐lymphocyte response upon adeno‐associated virus (AAV) vector delivery into dendritic cells

Abstract

Hepatitis B virus (HBV) has been an increasing problem throughout the world and remains difficult to treat. But immunotherapeutic approaches offer new, effective treatments. Three recombinant adeno-associated virus (AAV) type 2 vectors, carrying one of the HBV S, C or X gene, were used to load (transduce) professional antigen-presenting dendritic cells (DC) for the purpose of stimulating cytotoxic T lymphocytes (CTL) in vitro. It was found that all three recombinant AAV/HBV antigen virus loaded DC at approximately 90% transduction efficiency. Most importantly, all three AAV-loaded DC stimulated rapid, antigen-specific and major histocompatibility complex (MHC)-restricted CTL. In vitro, these CTL killed (30-50%) synthetic antigen-positive autologous targets as well as HepG2 liver cell targets. In comparing the three antigens, it was found that AAV/HBV-C-derived CTL consistently had the highest killing efficiency. CTL derived from AAV/HBV-C-loaded DC also showed significantly higher killing of targets than that from bacterially generated C-protein-loaded DC. Further studies showed that AAV/HBV-C-derived CTL had higher interferon (IFN)-gamma. These data suggest that AAV/HBV antigen gene-loading of DC may be useful for immunotherapeutic protocols against HBV infection and that the HBV C antigen may be the most useful for this purpose.

HIV-1 gp120-induced migration of dendritic cells is regulated by a novel kinase cascade involving Pyk2, p38 MAP kinase, and LSP1

“…Several recent studies demonstrate that recombinant AAV vectors can be used to transduce DCs efficiently, mediating long-term gene expression and causing minimal toxicity. [42][43][44] In addition, we achieved higher efficiency of transduction using AAV-5 vector in comparison with AAV-2. This is in agreement with a recent study that has shown a strong tropism of AAV5 serotype for human DCs.…”

Optimized Transduction of Human Monocyte-Derived Dendritic Cells by Recombinant Adeno-Associated Virus Serotype 6

“…More recent studies have confirmed the ability of AAV2 to stimulate antigen-specific CD8 þ T cells after ex vivo transduction of human DCs and revealed that rAAV2/1 (i.e., rAAV2 pseudotyped with type 1 capsid) is more efficient than rAAV2 in transducing MoDCs (You et al, 2006;Veron et al, 2007). Although these studies confirm the ability of DCs to present AAV-encoded antigen to T cells and thus the potential utility of rAAV as a vaccine vector, the successful deployment of rAAV-based vaccines may be limited by the tropism of these serotypes for other tissue/cell types.…”

Dendritic cells in chronic viral hepatitis B and C: victims or guardian angels?

“…Both in vitro and in vivo, several studies have demonstrated that DCs expressing HBV or HCV antigens induce antigen-specific CD4 + and CD8 + T cell responses 111 112 113 114. It is difficult, however, to study the experimental approaches of DC-based immunisation against HBV and HCV to terminate persistent infection in vivo, because the host range of HBV and HCV is limited to man and chimpanzees.…”