RESUMEN
Transcriptional regulation of numerous interferon-regulated genes, including Toll-like receptor 3 (Tlr3), which encodes an innate immune sensor of viral double-stranded RNA, depends on the interferon regulatory factor 1 (IRF1) and IRF2 transcription factors. We detected specific abrogation of macrophage responses to polyinosinic-polycytidylic acid (poly(I:C)) resulting from three independent N-ethyl-N-nitrosourea-induced mutations in host cell factor C2 (Hcfc2). Hcfc2 mutations compromised survival during influenza virus and herpes simplex virus 1 infections. HCFC2 promoted the binding of IRF1 and IRF2 to the Tlr3 promoter, without which inflammatory cytokine and type I IFN responses to the double-stranded RNA analogue poly(I:C) are reduced in mouse macrophages. HCFC2 was also necessary for the transcription of a large subset of other IRF2-dependent interferon-regulated genes. Deleterious mutations of Hcfc2 may therefore increase susceptibility to diverse infectious diseases.
Asunto(s)
Factor 1 Regulador del Interferón/genética , Factor 2 Regulador del Interferón/genética , Macrófagos/metabolismo , Receptor Toll-Like 3/genética , Factores de Transcripción/genética , Animales , Línea Celular Tumoral , Femenino , Regulación de la Expresión Génica/efectos de los fármacos , Células HEK293 , Herpes Simple/genética , Herpes Simple/metabolismo , Herpes Simple/virología , Herpesvirus Humano 1/fisiología , Humanos , Subtipo H1N1 del Virus de la Influenza A/fisiología , Factor 1 Regulador del Interferón/metabolismo , Factor 2 Regulador del Interferón/metabolismo , Estimación de Kaplan-Meier , Macrófagos/efectos de los fármacos , Macrófagos/virología , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Células 3T3 NIH , Infecciones por Orthomyxoviridae/genética , Infecciones por Orthomyxoviridae/metabolismo , Infecciones por Orthomyxoviridae/virología , Poli I-C/farmacología , Receptor Toll-Like 3/metabolismo , Factores de Transcripción/metabolismoRESUMEN
The major goal of this study was to perform an in depth characterization of the "gene signature" of human FoxP3(+) T regulatory cells (Tregs). Highly purified Tregs and T conventional cells (Tconvs) from multiple healthy donors (HD), either freshly explanted or activated in vitro, were analyzed via RNA sequencing (RNA-seq) and gene expression changes validated using the nCounter system. Additionally, we analyzed microRNA (miRNA) expression using TaqMan low-density arrays. Our results confirm previous studies demonstrating selective gene expression of FoxP3, IKZF2, and CTLA4 in Tregs. Notably, a number of yet uncharacterized genes (RTKN2, LAYN, UTS2, CSF2RB, TRIB1, F5, CECAM4, CD70, ENC1 and NKG7) were identified and validated as being differentially expressed in human Tregs. We further characterize the functional roles of RTKN2 and LAYN by analyzing their roles in vitro human Treg suppression assays by knocking them down in Tregs and overexpressing them in Tconvs. In order to facilitate a better understanding of the human Treg gene expression signature, we have generated from our results a hypothetical interactome of genes and miRNAs in Tregs and Tconvs.
