Biochemistry 1995, 34, 12481- 12488
12481
Dissociation Kmetics between a Mouse Fc Receptor (FcyRII) and IgG: Measurement by Total Internal Reflection with Fluorescence Photobleaching Recovery' Helen V. Hsieh: and Nancy L. Thompson* Department of Chemistry, University of North Carolina, Chapel Hill, North Curolina 27599-3290 Received January 4, 1995; Revised Manuscript Received June 26, 1995@
Total internal reflection with fluorescence photobleaching recovery (TIR-FPR) has been used to examine the dissociation kinetics between monomeric mouse IgG and a mouse Fc receptor (moFcyRII) reconstituted into substrate-supported planar membranes. IgGl , IgG2a, and IgG2b exhibited similar dissociation kinetics, whereas IgG3 did not bind. The fluorescence recovery curves for the IgG-moFcyRII interactions were best described by two reversible components (1.4 SKI,66% and 0.06 s-l, 18%) and an irreversible component (
