We have studied the kinetics of binding of dissolved antigens to antibody-receptors on the surface of the intact living cells. We have combined the Scanning Flow Cytometry with fluorescent immunoassay. Measurements of the kinetics were carried out for rabbit anti-mouse immunoglobulins that bind to receptors of the mouse hybridomas. Anti-mouse immunoglobulins were labeled with fluorescein isothiocyanate molecules (FITC). The individual cells were identified from the native Scanning Flow Cytometer records in our experiment. The kinetics of the formation of antigen-antibody complexes was measured from the fluorescence from the individual cells. A kinetic scheme for the heterogeneous reactions between ligands and receptors has been suggested. This scheme utilizes the concept of a distribution function of an amount of active receptors on the cell surface. The analytical solution for the system of the kinetic equations has been found in the reaction-limited approximation. The experimental kinetics were fitted by this mathematical model to determine the rate constant for binding reaction of the used antigen-antibody pair.

Date Published: 1 June 1999
PDF: 8 pages
Proc. SPIE 3604, Optical Diagnostics of Living Cells II, (1 June 1999); doi: 10.1117/12.349201

Published in SPIE Proceedings Vol. 3604:
Optical Diagnostics of Living Cells II
Daniel L. Farkas; Robert C. Leif; Bruce J. Tromberg, Editor(s)