Combined HIV-1 Envelope Systemic and Mucosal Immunization of Lactating Rhesus Monkeys Induces a Robust Immunoglobulin A Isotype B Cell Response in Breast Milk.

Dr. Justin Pollara is a member of the Duke Human Vaccine Institute and the Duke Center for Human Systems Immunology, and is Associate Director of the Duke Center for AIDS Research (CFAR) Developmental Core. He received his PhD from North Carolina State University and completed his postdoctoral training as a recipient of the Duke NIH Interdisciplinary Research Training Program in AIDS (IRTPA) T32 award in the laboratory of Dr. Guido Ferrari. He joined the faculty of the Duke Department of Surgery in 2016.

A common theme of research performed in Dr. Pollara’s laboratory is a focus on interactions between innate and adaptive immunity. Dr. Pollara’s work has contributed significantly to the understanding of the roles played by non-neutralizing antibodies in limiting HIV-1 disease progression, and in prevention of infection or control of virus replication in preclinical and clinical HIV-1 vaccine trials. Dr. Pollara’s research has also identified specific components of the immune response that reduce the risk of vertical transmission of both HIV-1 and human cytomegalovirus. The Pollara lab characterizes the phenotype and functionality of antibody-interacting innate immune cells and explores how natural genetic variation in antibodies and antibody receptors may contribute to vaccine responsiveness and immune competence. Further, with a strong interdisciplinary and collaborative approach, the Pollara Lab has broadened its scope beyond infectious diseases and is now actively leading studies aimed at understanding how inflammation, antibodies, innate immune cells, and newly described populations of T cells promote allograft injury that underlies rejection of transplanted organs.

Dr. Shen is an Associate Director and Deputy of the Laboratory for HIV and COVID-19 Vaccine Research & Development in the Department of Surgery, Division of Surgical Sciences at Duke University Medical Center. Her research interest focuses on the humoral immune response following virus infection or vaccination. During the past decade, she has worked intensively on the specificity and breadth of binding antibody responses against HIV.

Dr. Shen’s team developed assays and analytical tools for a peptide microarray assay for finely mapping of HIV-1 cross-subtype linear epitopes targeted by antibody responses in human specimens as well as animal models, and adopted a multiplex binding antibody assay for evaluating binding antibody responses. With these technologies, her team evaluated various clinical HIV-1 vaccine studies and NHP studies. Building upon the data generated by her team and other collaborators, Dr. Shen works with bioinformatics and biostatistics personnel on deciphering immune correlates in both human clinical trials and nonhuman primate studies. During the COVID-19 pandemic, her team expanded their research to SARS-COV-2 antibody responses.

In 2021, Dr. Shen became the Deputy Director of the Laboratory for HIV and COVID-19 Vaccine Research & Development, alongside Laboratory Director Dr. Montefiori.  The laboratory established a lentivirus-based pseudovirus SARS-CoV-2 neutralization assay that has been FDA-approved. The laboratory is assessing neutralizing antibody responses for multiple phase 3 COVID-19 vaccine trials. In addition to supporting clinical trials, the lab has a strong focus on characterizing SARS-CoV-2 variants for their neutralizing susceptibility and potential to escape from vaccine-elicited immune responses.

Meanwhile, Dr. Shen’s team remains highly active in HIV-1 vaccine research, evaluating neutralizing responses in preclinical and clinical HIV vaccine trials as a core laboratory for multiple networks including the HIV Vaccine Trials Network (HVTN), the Collaboration for AIDS Vaccine Discovery (CAVD) funded by Bill & Melinda Gates Foundation, as well as the NIH Nonhuman Primate Core Humoral Immunology Laboratory for AIDS Vaccine which Dr. Shen directs.

Viral inhibition of host immune defenses
Many viruses have evolved mechanisms to protect themselves from host immune defenses. Among this group are the orthopoxviruses, whose members include smallpox virus, one of the deadliest of human viruses, and cowpox virus, the virus that Edward Jenner used to begin the eradication of smallpox.

One of the especially interesting features of theses viruses is their ability to interfere with a wide range of innate and adaptive immune responses to infection. For example, we have found that cowpox virus inhibits inflammation by suppressing the actions of cytokines controlling inflammatory processes. Moreover, the virus does this in several ways: by preventing the synthesis of cytokines; by interfering with normal cytokine-receptor interactions; and by inhibiting cytokine-signaling pathways.

Our main research objectives are to identify mechanisms of virus-host interaction leading to the modification or alteration of host functions. Our working model is that such interactions are amongst the most important factors in viral pathogenesis. In addition, knowledge of these virus-host interactions should help in the development of new vaccines and therapies for a variety of conditions associated with infectious diseases, inflammatory diseases, autoimmune diseases, cancers, and organ transplantation.

Development of improved viral vaccines
Several excellent vaccine platforms exist, but among these vaccinia virus vaccines have unusual potential for targeting multiple different pathogens because of the extraordinary capacity of these vectors to encode multiple foreign proteins. Replication-defective vaccinia vectors are extremely safe. However, this safety comes at a cost. Because only a small amount of antigen can be produced during the single cycle of viral replication, vectors of this type typically require high doses and multiple boosts to induce protective immune responses.  We are interested in finding ways to enhance the immunogenicity of these replication-defective vaccine viruses without compromising on safety.