CX3CL1 homo-oligomerization drives cell-to-cell adherence
Ostuni MA, Hermand P, Saindoy E, Guillou N, Guellec J, Coens A, Hattab C, Desuzinges-Mandon E, Jawhari A, Iatmanen-Harbi S, Lequin O, Fuchs P, Lacapere JJ, Combadière C, Pincet F, Deterre P.
Sci Rep. 2020. 10:9069.
This paper describes the study of the cluster molecule CX3CL1, which induce adherence of CX3CR1+ cells to the endothelium.
CX3CL1 transfected L929 were incubated with CFSE-stained CHOCX3CR1 cells and the cell-cell interaction was followed in real-time with LigandTracer Green (Blue-Green detector). Minimal binding was observed to non-transfected L929 cells. The presence of a peptide that hinders CX3CL1 oligomerization (TM24) or an anti-CX3CL1 antibody almost completely inhibited the cell-cell adhesion, while no effect was observed in the presence of the irrelevant SCR24 peptide.
In a second experiment, the binding of Alexa Fluor 647-labeled CX3CL1 to stably transfected CHOCX3CR1 cells in the presence/absence of either TM24 or excess non-stained CX3CL1 were measured with the Red-NIR detector of LigandTracer Green. TM24 barely affected the interaction, indicating that the inhibition of the cell-cell adhesion described above was due to prevented oligomerization and not some interference with the CX3CL1-CX3CR1 binding interface. Non-stained CX3CL1 significantly reduced the CX3CL1-CHOCX3CR1 interaction, showing specificity.