Impact of HIV Induced Immune Dysregulation on KSHV Oral Infection - PROJECT SUMMARY Most HIV infections are initiated at mucosal surfaces, including the oral cavity, where transmission can occur through breastfeeding or oral–genital contact. Despite the effectiveness of antiretroviral therapy (ART), HIV persists in infected individuals as integrated, latent proviruses within long-lived reservoir cells, representing a major barrier to viral eradication. The tonsil is a secondary lymphoid organ that serves as a first line of immune defense against pathogens entering through oral and nasal routes. HIV-associated immune dysregulation is thought to compromise lymphoid tissue function, including that of the tonsils, leading to impaired antibody production, T cell dysfunction, cytokine imbalance, autoimmunity, and increased susceptibility to viral co- infections. Kaposi sarcoma–associated herpesvirus (KSHV), a human gamma-herpesvirus, is frequently co- infected with HIV and is a major contributor to AIDS-related malignancies. The oral cavity is a primary site of KSHV replication, where high levels of infectious virus are produced and shed in saliva, facilitating transmission through the salivary–mucosal route. B lymphocytes serve as the principal reservoir for lifelong KSHV persistence. Accumulating evidence suggests that HIV infection enhances oral acquisition of KSHV, promotes its persistent infection, and increases the risk of KSHV-associated tumorigenesis; however, the underlying immune mechanisms remain poorly defined. Recently, human tonsil organoids have emerged as highly physiologically relevant in vitro models for studying viral infection, immune responses, and vaccine evaluation. These three-dimensional culture systems preserve tissue architecture and immune cell diversity, offering significant advantages over traditional models while reducing reliance on animal studies. In this exploratory R21 project, we will leverage human tonsil organoid cultures to investigate how HIV-induced immune dysregulation impacts oral infection by the oncogenic gamma-herpesvirus KSHV. Specifically, we will establish chronic HIV infection in tonsil organoids and comprehensively characterize HIV-driven alterations in immune cell composition and function (Aim 1). In parallel, we will examine how HIV modulates KSHV co-infection within tonsils, with a focus on previously underappreciated immune mechanisms, including natural killer (NK) cell–mediated immunosurveillance (Aim 2).
