Elucidating Viral G Protein-Coupled Receptor’s Role in Innate Immunity in Bystander Host Cells
By: Amanda Verzosa
Department: Cellular & Molecular Biology
Faculty Advisor: Dr. Erica L. Sanchez
Abstract: Kaposi’s Sarcoma-associated Herpesvirus (KSHV) is a human herpesvirus and the infectious cause of Kaposi’s Sarcoma; an angioproliferative, endothelial cell neoplasm that predominantly affects patients with HIV/AIDS. KSHV encodes for a viral G protein-coupled receptor (vGPCR), a receptor with homology to human chemokine receptors and a prominent gene expressed during KSHV lytic infection. KSHV infected cells secrete extracellular vesicles (EVs), that are known to activate the complement system, an innate immune response. vGPCR and its role in inducing specific innate immune responses has not been fully elucidated. We determine if vGPCR plays a role in EV-induced complement activity. We hypothesize that vGPCR alters the composition of host cell EVs and induces the complement system in bystander cells. We have successfully generated cells stably expressing vGPCR using an expression vector, which has been shown through immunofluorescence assays and flow cytometry analyses. Currently, cells overexpressing vGPCR are being used to test for complement activity in bystander cells through an immunofluorescence and flow cytometry approach. C5b-9, a complement protein, is expected to deposit onto the surface of bystander cells when treated with conditioned media from cells overexpressing vGPCR. Additionally, bystander cells will be treated with EVs from cells overexpressing vGPCR to test for complement activity. Results will determine whether vGPCR plays a role in EV-induced complement activity in bystander cells. This research will contribute to the understanding of the molecular and cellular mechanisms of vGPCR, which can lead to preventative therapeutic treatments for KSHV oncogenesis.