Characterization of lamprey (Lampetra japonica) tnfr10-like gene: A potential granulocyte marker molecule and its immune functions.

Tumor necrosis factor receptor superfamily (TNFRSF) is an ancient protein superfamily. By binding to tumor necrosis factor (TNF), it can participate in inflammatory response, apoptosis, lymphocyte homeostasis and tissue development. Seven TNFR members have previously been identified in lampreys but detailed functions of TNFR members are not yet to be resolved. Here, we demonstrate some of the distinguishing features of TNFR10-like member which belongs to TNFRSF. The immunohistochemical results indicate that the TNFR10-like protein is abundant in vascular epithelial cells of the lamprey typhlosole and gills. The expression of tnfr10-like gene has a significantly increased at transcription level after Vibrio anguillarum, Staphylococcus aureus and Poly (I:C) stimulation. Notably, TNFR10-like is specifically expressed in the granulocytes of lamprey peripheral blood and supraneural body. Besides, overexpression tnfr10-like gene in HEK-293 T cells cause a decrease in cell activity and able to activate nuclear transcription factor-κB (NF-κB). Together, these results imply that L-TNFR10-like may play a vital role as a potential marker in lamprey granulocytes and may also be involved in regulation of immune response mediated by itself.