Sunday, May 11, 2025
5/11/2025
HSV-1 Encoded MicroRNAs in the Pathogenesis and Treatment of Ocular Herpes - Herpes Simplex Virus-1 (HSV-1), a highly transmissible infection, is common and endemic throughout the world. Similar to other human herpesviruses (HHV), HSV-1 maintains lifelong latency inside host that requires immune evasion through various sophisticated mechanisms. Although HSV-1 is equipped with large repertoire (>80) of protein coding genes, the commonly accepted manifestations of viral gene expression during latency are the accumulation of a noncoding transcript and a set of microRNAs (miR). HSV-1 encoded viral miRNAs (v-miRs) are demonstrated to control expression of both viral and host transcripts and regulate viral tropism, lytic switching, immune subversion, etc. While multiple studies have examined HSV-1 profiles in various cell lines, key biological functions of these v-miRs remain unknown. Therefore, we propose to evaluate: (1) systematic expression dynamics of v-miRs during disease progression and reactivation, (2) comprehensive role in the pathogenesis by perturbing immune cells functions and (3) therapeutic targeting of v-miR by synthetic oligonucleotides to mitigate HSV-1-mediated ocular herpes. Using our established mouse model of ocular herpes, we will compare HSV-1 miRNA profiles in primary and reactivated mice corneal tissues and blood. Identifying positive and negative regulatory v-miRs can yield novel insights into host-virus interaction. The information gained will be used in designing therapeutic v-miR Inhibitors to silence candidate v-miRs functions. Effect of synthetic oligonucleotides (v-miR Inhibitors) targeting candidate v-miRs will be assessed on ocular disease progression in a mice model. V-miR inhibitors (alone or in combination) will be topically delivered and virus release, viral transcript/genome, and disease severity score will be measured. Next, we will evaluate how v-miRs can render host immune system dysfunctional, an integral feature required for HSV-1 persistence. Using v-miR inhibitors, we will assess whether immune infiltration and functions can be restored in vivo. Immune cell subsets will be comprehensively profiled in virus-infected animals treated with v-miR inhibitor using flow cytometry and single cell RNA sequencing. In addition, transcript expression profiles of genes related to antigen processing/presentation pathway, critical for potent antiviral response, will be quantified. This will identify the in vivo mechanisms through which v-miRs can facilitate immune evasion in ocular tissues. Next, we will dissect underlying mechanisms of v-miR-mediated dysregulation of antigen processing/presentation by macrophages and dendritic cells and activation of T cells. V-miR expressing myeloid cells will be assessed for uptake and processing of viral antigens and activation of autologous T helper (CD4+) and T cytotoxic (CD8+) cells. In addition, we will assess the impact of v-miRs on the polarization of CD4+ T cells. The data generated will provide significant information to existing knowledge gaps. Overall, the proposed translational study focuses on identifying the therapeutic and mechanistic aspect of v-miRs in ocular disease pathogenesis through modulation of immune cell responses.
HHS’ Tracking Accountability in Government Grants System (TAGGS) website provides access to detailed descriptions of grants, loans, aggregated direct payments and other types of financial assistance awarded by the HHS Operating Divisions (OPDIVs) and the Office of the Secretary Staff Divisions (STAFFDIVs).