First Author | Naskar D | Year | 2014 |
Journal | J Immunol | Volume | 192 |
Issue | 9 | Pages | 4386-97 |
PubMed ID | 24706725 | Mgi Jnum | J:209957 |
Mgi Id | MGI:5569176 | Doi | 10.4049/jimmunol.1302817 |
Citation | Naskar D, et al. (2014) Wnt5a-Rac1-NF-kappaB homeostatic circuitry sustains innate immune functions in macrophages. J Immunol 192(9):4386-97 |
abstractText | Macrophages play a critical role in innate immunity. Differentiation Ags present on macrophages such as CD14 orchestrate the first line of defense against infection. The basal/homeostatic signaling scheme that keeps macrophages thus groomed for innate immune functions remains unresolved. Wnt5a-Fz5 signaling being a primordial event during cell differentiation, we examined the involvement of Wnt5a-Fz5 signaling in the maintenance of innate immune functions. In this study, we demonstrate that innate immune functions of macrophages ensue at least partly through a homeostatic Wnt5a-Fz5-NF-kappaB (p65) circuit, which is Rac1 dependent. The autocrine/paracrine Wnt5a-Fz5-Rac1-p65 signaling cascade not only maintains basal levels of the immune defense modulating IFNs and CD14; it also supports macrophage survival. Wnt5a-Fz5-Rac1 signaling mediated p65 homeostasis in turn sustains Wnt5a expression in a feed-forward mode. The natural immune response of macrophages to Escherichia coli/LPS and virus is accordingly sustained. The depiction of sustenance of innate immune functions as an outcome of a homeostatic Wnt5a-p65 axis unfolds previously unidentified details of immune regulation and provides new insight into homeostatic cell signaling. |