An Image-Based Genetic Assay Identifies Genes in T1D Susceptibility Loci Controlling Cellular Antiviral Immunity in Mouse

Abstract

The pathogenesis of complex diseases, such as type 1 diabetes (T1D), derives from interactions between host genetics and environmental factors. Previous studies have suggested that viral infection plays a significant role in initiation of T1D in genetically predisposed individuals. T1D susceptibility loci may therefore be enriched in previously uncharacterized genes functioning in antiviral defense pathways. To identify genes involved in antiviral immunity, we performed an image-based high-throughput genetic screen using short hairpin RNAs (shRNAs) against 161 genes within T1D susceptibility loci. RAW 264.7 cells transduced with shRNAs were infected with GFP-expressing herpes simplex virus type 1 (HSV-1) and fluorescent microscopy was performed to assess the viral infectivity by fluorescence reporter activity. Of the 14 candidates identified with high confidence, two candidates were selected for further investigation, Il27 and Tagap. Administration of recombinant IL-27 during viral infection was found to act synergistically with interferon gamma (IFN-γ) to activate expression of type I IFNs and proinflammatory cytokines, and to enhance the activities of interferon regulatory factor 3 (IRF3). Consistent with a role in antiviral immunity, Tagap-deficient macrophages demonstrated increased viral replication, reduced expression of proinflammatory chemokines and cytokines, and decreased production of IFN-β. Taken together, our unbiased loss-of-function genetic screen identifies genes that play a role in host antiviral immunity and delineates roles for IL-27 and Tagap in the production of antiviral cytokines.

Identification of key regulatory genes and their working mechanisms in type 1 diabetes

“…Additionally, the MAPK gene is involved in the initiation and development of T1D [ 44 ]. HSV1 infection has also been reported to influence T1D progression [ 45 ]. This evidence suggests that the cell cycle and MAPK signaling pathways enriched by KEGG may have an important regulatory role in T1D.…”

TAGAP instructs Th17 differentiation by bridging Dectin activation to EPHB2 signaling in innate antifungal response

“…A previous study found that TAGAP is involved in HSVmediated induction of the TLR3 pathway 24 , and we first explored the function of TAGAP in macrophages by examining TLR3 or TLR4 ligands-induced signaling pathway activation in bone marrow-derived macrophages (BMDMs) from heterozygous control mice or TAGAP-deficient mice. We did not find any significant difference in terms of signaling activation and gene expression between BMDMs from heterozygous control mice or TAGAP-deficient mice after TLR3 and TLR4 ligands stimulation ( Supplementary Fig.…”

TAGAP expression influences CD4+ T cell differentiation, immune infiltration, and cytotoxicity in LUAD through the STAT pathway: implications for immunotherapy

“…TAGAP has been discovered to have crucial effects through additional pathways and systems, in addition to studies in the tumor immune microenvironment. TAGAP-deficient macrophages had enhanced viral replication of herpes simplex virus type 1, lower expression of pro-inflammatory chemokines and cytokines, and lower production of IFN-β, according to Juan Liao et al., implying that TAGAP plays a significant role in antiviral cytokine production ( 30 ). TAGAP governs the cytoskeletal architecture of actin fibers via RhoA, which is required for cell contractility and the cycle of integrin attachment and separation required for directional migration of thymocytes, according to Jonathan S. Duke-Cohan et al ( 19 ).…”