The binding of IgG1 containing immune complexes to the FcR of allogenically activated T cells induces changes in the membrane potential and the cell surface charge.
The effect on membrane potential and cell surface charge of binding immune complexes containing IgG1 and IgG2a monoclonal antibodies to Fc receptors was studied in resting and allogenically activated murine T cells. IgG1 complexed by antigen or heat aggregation induced electrophysiological changes on activated T cells. A biphasic alteration of membrane potential was detected by measurement of the intra- and extracellular distribution of the fluorescent dye, DiOC6. A short-lived hyperpolarization, detectable for 4-6 min after adding the respective ligand, was followed by a longer lasting depolarization. The cell surface charge, measured by cell electrophoresis, was also changed. This alteration was detected 2-4 hr after addition of immune complexes and disappeared by the 8th hr of incubation. Monoclonal antibody 2.4.G2, reactive with mouse FcR, induced a similar membrane potential response on activated T cells, but did not affect the cell surface charge. Monomeric IgGs and complexes of IgG2a did not modify these parameters. FcR ligands had no effect on the studied characteristics of resting T cells.
Huckel
C
C
Institute of Biochemistry, Wilhelm-Pieck-University Rostock, G.D.R.
Sandor
M
M
Jenssen
H L
HL
Rychly
J
J
Brock
J
J
Gergely
J
J
D000818:Animals; D000936:Antigen-Antibody Complex / Q000378:metabolism*; D000943:Antigens, Differentiation / Q000378:metabolism*; D002462:Cell Membrane / Q000502:physiology; D004594:Electrophysiology; D005260:Female; D007074:Immunoglobulin G / Q000276:immunology; D008213:Lymphocyte Activation; D008564:Membrane Potentials; D051379:Mice; D008810:Mice, Inbred C57BL; D008808:Mice, Inbred CBA; D011961:Receptors, Fc / Q000378:metabolism*; D017452:Receptors, IgG; D013601:T-Lymphocytes / Q000276:immunology / Q000502:physiology*
D000936:Antigen-Antibody Complex; D000943:Antigens, Differentiation; D007074:Immunoglobulin G; D011961:Receptors, Fc; D017452:Receptors, IgG