Gerard Zurawski Ph.D.

Posted March 15th 2017

Superiority in Rhesus Macaques of Targeting HIV-1 Env Gp140 to CD40 Versus LOX-1 in Combination with Replication Competent NYVAC-KC for Induction of Env-Specific Antibody and T Cell Responses.

Gerard Zurawski Ph.D.

Gerard Zurawski Ph.D.

Zurawski, G., X. Shen, S. Zurawski, G. D. Tomaras, D. C. Montefiori, M. Roederer, G. Ferrari, C. Lacabaratz, P. Klucar, Z. Wang, K. E. Foulds, S. F. Kao, X. Yu, A. Sato, N. L. Yates, C. LaBranche, S. Stanfield-Oakley, K. Kibler, B. Jacobs, A. Salazar, S. Self, J. Fulp, R. Gottardo, L. Galmin, D. Weiss, A. Cristillo, G. Pantaleo and Y. Levy (2017). “Superiority in rhesus macaques of targeting hiv-1 env gp140 to cd40 versus lox-1 in combination with replication competent nyvac-kc for induction of env-specific antibody and t cell responses.” J Virol: 2017 Feb [Epub ahead of print].

Full text of this article.

We compared the HIV-1-specific immune responses generated by targeting HIV-1 envelope protein (Env gp140) to either CD40 or LOX-1, two endocytic receptors on dendritic cells (DCs), in Rhesus macaques primed with a poxvirus vector (NYVAC-KC) expressing Env gp140. The DC-targeting vaccines, humanized recombinant monoclonal antibodies fused to Env gp140, were administered as a boost with poly ICLC adjuvant either alone or co-administered with the NYVAC-KC vector. All the DC-targeting vaccine administrations with poly ICLC increased the low-level serum anti-Env IgG responses elicited by NYVAC-KC priming significantly more (up to P =0.01) than a group without poly ICLC. The responses were robust, cross-reactive, and contained antibodies specific to multiple epitopes within gp140 including the C1, C2, V1-3, C4, C5, and gp41 immuno-dominant regions. The DC-targeting vaccines also elicited modest serum Env-specific IgA responses. All groups gave serum neutralization activity limited to Tier 1 viruses and antibody dependent cytotoxicity responses (ADCC) after DC-targeting boosts. Furthermore, CD4+ and CD8+ T cell responses specific to multiple Env epitopes were strongly boosted by the DC-targeting vaccines + poly ICLC. Together, these results indicate that prime/boost immunization via NYVAC-KC and either alphaCD40.Env gp140/poly ICLC or alphaLOX-1.Env gp140/poly ICLC induced balanced antibody and T cell responses against HIV-1 Env. Co-administration of NYVAC-KC with the DC-targeting vaccines increased T cell responses, but had minimal effects on antibody responses except for suppressing serum IgA responses. Overall, compared to LOX-1, targeting Env to CD40 gave more robust T cell and serum antibody responses with broader epitope representation and greater durability.IMPORTANCE An effective vaccine to prevent HIV-1 infection does not yet exist. An approach to elicit strong protective antibody development is to direct virus protein antigens specifically to dendritic cells, which are now known to be the key cell type for controlling immunity. Here we have tested in non-human primates two prototype vaccines engineered to direct the HIV-1 coat protein Env to dendritic cells. These vaccines bind to either CD40 or LOX-1, two dendritic cell surface receptors with different functions and tissue distributions. We tested the vaccines described above in combination with attenuated virus vectors that express Env. Both vaccines, but especially that delivered via CD40, raised robust immunity against HIV-1 as measured by monitoring potentially protective antibody and T cell responses in the blood. The safety and efficacy of the CD40-targeted vaccine justifies further development for future human clinical trials.


Posted June 15th 2016

Targeting HIV-1 Env gp140 to LOX-1 Elicits Immune Responses in Rhesus Macaques.

Gerard Zurawski Ph.D.

Gerard Zurawski Ph.D.

Full text of this article.

Improved antigenicity against HIV-1 envelope (Env) protein is needed to elicit vaccine-induced protective immunity in humans. Here we describe the first tests in non-human primates (NHPs) of Env gp140 protein fused to a humanized anti-LOX-1 recombinant antibody for delivering Env directly to LOX-1-bearing antigen presenting cells, especially dendritic cells (DC). LOX-1, or 1ectin-like oxidized low-density lipoprotein (LDL) receptor-1, is expressed on various antigen presenting cells and endothelial cells, and is involved in promoting humoral immune responses. The anti-LOX-1 Env gp140 fusion protein was tested for priming immune responses and boosting responses in animals primed with replication competent NYVAC-KC Env gp140 vaccinia virus. Anti-LOX-1 Env gp140 vaccination elicited robust cellular and humoral responses when used for either priming or boosting immunity. Co-administration with Poly ICLC, a TLR3 agonist, was superior to GLA, a TLR4 agonist. Both CD4+ and CD8+ Env-specific T cell responses were elicited by anti-LOX-1 Env gp140, but in particular the CD4+ T cells were multifunctional and directed to multiple epitopes. Serum IgG and IgA antibody responses induced by anti-LOX-1 Env gp140 against various gp140 domains were cross-reactive across HIV-1 clades; however, the sera neutralized only HIV-1 bearing sequences most similar to the clade C 96ZM651 Env gp140 carried by the anti-LOX-1 vehicle. These data, as well as the safety of this protein vaccine, justify further exploration of this DC-targeting vaccine approach for protective immunity against HIV-1.


Posted May 15th 2016

Intradermal injection of an anti-langerin-hivgag fusion vaccine targets epidermal langerhans cells in nonhuman primates and can be tracked in vivo.

Gerard Zurawski Ph.D.

Gerard Zurawski, Ph.D.

Salabert, N., B. Todorova, F. Martinon, R. Boisgard, G. Zurawski, S. Zurawski, N. Dereuddre-Bosquet, A. Cosma, T. Kortulewski, J. Banchereau, Y. Levy, R. Le Grand and C. Chapon (2016). “Intradermal injection of an anti-langerin-hivgag fusion vaccine targets epidermal langerhans cells in nonhuman primates and can be tracked in vivo.” European Journal of Immunology 46(3): 689-700.

Full text of this article.

The development of new immunization strategies requires a better understanding of early molecular and cellular events occurring at the site of injection. The skin is particularly rich in immune cells and represents an attractive site for vaccine administration. Here, we specifically targeted vaccine antigens to epidermal Langerhans cells (LCs) using a fusion protein composed of HIV antigens and a monoclonal antibody targeting Langerin. We developed a fluorescence imaging approach to visualize, in vivo, the vaccine-targeted cells. Studies were performed in nonhuman primates (NHPs) because of their relevance as a model to assess human vaccines. We directly demonstrated that in NHPs, intradermally injected anti-Langerin-HIVGag specifically targets epidermal LCs and induces rapid changes in the LC network, including LC activation and migration out of the epidermis. Vaccine targeting of LCs significantly improved anti-HIV immune response without requirement of an adjuvant. Although the co-injection of the TLR-7/8 synthetic ligand, R-848 (resiquimod), with the vaccine, did not enhance significantly the antibody response, it stimulated recruitment of HLA-DR+ inflammatory cells to the site of immunization. This study allowed us to characterize the dynamics of early local events following the injection of a vaccine-targeted epidermal LCs and R-848.