Abstract - Shang

TNFRSF/TNFSF plays important role in cancer immunotherapy. As one of members, CD95/CD95L has raised great attention in recent reserach. CD95 is type I transmembrane protein and CD95L is type II transmembrane protein. In this study, we probed membrane CD95 signaling on Hela WT from macro to micro perspective. First, we used apoptosis dynamics measurements to test CD95L variants at varying concentraions. It can be observed that at 1000 ng/ml, IZCD95L excels Flag-CD95L. Crosslinked Flag-CD95L with anti- Flag mAb showed best performance in apoptosis initiation. Which can be explained by higher binding affinity, as supported by native PAGE result and SPR measurements. From the nanoperspective, with increasing concentraion from 200 - 2000 ng/ml, CD95L/CD95 oligomerize into dimer/trimers, excluding a previously proposed hexagonal networks. In the  absence of ligand, CD95 form premarily monomers as shown in STED image analysis. Our findings have important implications for improving CD95 related therapeutic approaches.

Xiaoyue Shang, Gajen Thaventhiran and Cornelia Monzel (Experimental Medical Physics, HHU Düsseldorf)