1156. Autologous Aldrithiol-2-Inactivated HIV as an Immunogen for Therapeutic Dendritic Cell HIV Vaccines
Session: Poster Abstract Session: Innate and Adaptive Immunity to Infections
Saturday, October 22, 2011
Room: Poster Hall B1
Background:  Dendritic cell (DC) dysfunction may contribute to HIV pathogenesis. Successful DC immunization for HIV infection would provide valuable proof of concept that correction of defects in DC function during infection is vital to induction of adequate immune responses. We have previously demonstrated that DC from control donors pulsed with Aldrithiol-2 (2,2′-Dipyridyl disulfide,  AT-2)-inactivated HIV are highly immunogenic and stimulate both existing and novel HIV-specific T cell responses in vitro. We now undertake the development of an entirely autologous DC vaccine for therapeutic use in chronic HIV infection that utilizes AT-2-inactivated virus.  

Methods:  HIV from 6 donors was cultured from activated, autologous CD4+ T cells and then inactivated with AT-2 overnight.  Virus purification and removal of residual AT-2 was performed via ultracentrifugation and confirmed by immunoblot and HPLC. Viral inactivation was verified through two assays: measurement of Tat-regulated β-galactosidase reporter gene expression following infection of TZM-bl cells, and long-term T cell culture to evaluate for productive infection. Autologous monocyte-derived DC (moDC) were then pulsed with 100ng/ml of AT-2-inactivated virus and matured with poly I:C (Toll-like receptor 3 ligand). Cytokine production by the DC vaccine product was measured via cytokine bead array. Induction of HIV-specific responses was assessed following co-culture with autologous T cells.

Results:  We successfully propagated, inactivated, and purified autologous HIV to use as the DC vaccine immunogen. The inactivated virus preparations demonstrated no residual infectivity or presence of detectable AT-2. The poly I:C-matured, AT-2-inactivated HIV- pulsed moDC secreted high levels of IL-12p70, a pro-Th1 cytokine, and stimulated HIV-specific memory T cell responses as evidenced by intracellular cytokine staining for IFNγ and TNFα.

Conclusion:  We have demonstrated the feasibility and immunogenicity of an autologous AT-2-inactivated DC vaccine supporting its potential use for therapeutic immunization of chronically infected individuals.  These findings have led us to pursue an application for Investigational New Drug number from the U.S. FDA.


Subject Category: E. Innate and adaptive immunity to infections, including vaccine immunology

Meredith Spadaccia1, Elizabeth Miller2, Rachel Sabado2, Elena Chertova3, Julian Bess4, C. Mac Trubey4, Rose Marie Holman5, Jeff Lifson4 and Nina Bhardwaj2, (1)Cancer Institute, NYU Langone Medical Center, New York, NY, (2)New York University School of Medicine, New York, NY, (3)Protein Chemistry Laboratory, SAIC Frederick, Inc. , Frederick, MD, (4)AIDS and Cancer Virus Program, SAIC Frederick, Inc. , Frederick, MD, (5)NYU Langone Medical Center, New York, NY

Disclosures:

M. Spadaccia, None

E. Miller, None

R. Sabado, None

E. Chertova, None

J. Bess, None

C. M. Trubey, None

R. M. Holman, None

J. Lifson, None

N. Bhardwaj, dendreon: shares, N/A
rockefeller univerity: co-inventor on patents, Licensing agreement or royalty

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