Poly (I:C) induced immune response in lymphoid tissues involves three sequential waves of type I IFN expression

Abstract

An IFN-alpha heteroduplex-tracking assay (IFN-HTA) was developed to quantify the frequency of expression of the 16 genes coding for related interferon-alpha (IFN-alpha) subtypes in mice. In mLN of mice treated with Poly (I:C), we observed the induction of three sequential waves of type I IFN production, instead of two as is commonly described: early IFNs after 1 h (IFN-beta), late IFNs after 3 h (mostly IFN-alpha1, -alpha2, -alpha 4 and -alpha 5) and "secondary late IFNs" after 6 h (IFN-alpha 6T and -alpha 8/6). The late IFN wave was associated with the upregulation of the interferon regulatory factor (IRF)-7 mRNA and proteins, whereas the secondary late IFN wave was associated with a slight upregulation of IRF-8 mRNA. Type I IFNs produced in the thymus were associated with a distinct IRF mRNA expression pattern. This IFN-HTA strategy can serve as a useful tool to qualify and quantify the expression of various IFN-alpha subtypes under distinct immune responses and thus provides a first step in evaluating their function.

Influenza A Virus Protein PB1-F2 Exacerbates IFN-β Expression of Human Respiratory Epithelial Cells

“…On the basis of this analysis, we chose further to analyze IFN-b expression in A549 cells infected with the WT or the DF2 viruses because it is considered as the first line of defense against viral infection in mammals. IFN-g is not expected to be expressed in A549 epithelial cells, and IFN-a subtypes are induced in response to an autocrine or paracrine feedback loop mediated by IRF7 later during infection (30). Furthermore, in our conditions of culture and infection, we were able to detect the expression of a single IFN-a subtype: IFN-a4 (listed in Supplemental Table 2).…”

Molecular characterization and expression analysis of eleven interferon regulatory factors in half-smooth tongue sole, Cynoglossus semilaevis

“…Studies in mammals and teleosts have shown that although poly I:C can effectively upregulate the expression of some antiviral IRFs such as IRF1, IRF3, IRF7, IRF8, and IRF 9, it has no effect on the expression of IRF4 [69,82]. However, in our study, a strong induction of IRF4a was detected in the spleen and HK at 1 and 3 dpi after megalocytivirus infection, which is similar to the observation made for the IRF4 of O. fasciatus infected with rock bream iridovirus [73].…”

Molecular characterization and expression analysis of interferon regulatory factor 5 (IRF-5) in turbot, Scophthalmus maximus

“…Poly I:C, a synthetic mimic of dsRNA, is a known inducer of type I IFNs, IFN-g and ISGs [18,41e44]. In thymus of mice, IRF-5, as well as some antiviral IRFs (e.g., IRF-1, IRF-7, IRF-8 and IRF-9), has been reported to be up-regulated by poly I:C treatment [45]. Compared with the control fish, the expression of SmIRF-5 was found to slightly decline by day 0.5 or 1 in response to poly I:C stimulation.…”