Fig. 5.

CXCR3 can be spatially associated with CD3. (A) Mean FRET efficiencies were calculated for titrations of anti-CXCR3-PE and anti-CD3-APC demonstrating that the FRET seen is non-random. Fluorescence intensity is expressed as a percentage of the maximal median fluorescence intensity (MFI). The increasing percentage values corresponded to increasing anti-CD3ɛ antibody concentrations. (B) Control experiments demonstrated that the FRET signal is not due to non-specific spectral overlap (CD45/CXCR3 control), is specific for CXCR3 (CCR2/CD3 control), is ligand-dependent and is not entirely a consequence of receptor internalisation (reduction following acid wash). The bars show mean values ± SEM.