Purification and partial characterization of rat macrophage Fc receptor and binding factor for IgA.
By using a biotinylated ligand and Western blotting techniques, a receptor (RFc alpha) and a binding factor (BF) for IgA were detected, respectively, on membrane and in the cell-free culture supernatant of rat peritoneal macrophages. Extraction of the RFc alpha was obtained by solubilization of macrophages with Nonidet P-40, and purification was performed by HPLC affinity chromatography on a column derivatized with IgA. RFc alpha is formed of two subunits, with molecular masses of 56 and 70 kDa, which are both involved in the IgA binding ability of rat peritoneal macrophages. IgABF was recovered from the cell-free supernatant of a short-term culture of rat macrophages and was affinity-purified in the same manner as RFc alpha. Like RFc alpha, IgABF retained its IgA binding activity in its native, as well as denatured form. Since the molecular masses of RFc alpha and IgABF are similar, and IgABF competes with RFc alpha for IgA binding, one can assume that IgABF probably represents a shed RFc alpha.
Fargeas
C A
CA
Unité INSERM U157, Faculté de Chirurgie Dentaire, Strasbourg, France.
Scholler
M
M
Pini
A
A
Wachsmann
D
D
Poindron
P
P
Klein
J P
JP
D000818:Animals; D001202:Ascitic Fluid / Q000166:cytology; D001710:Biotin; D015153:Blotting, Western; D002846:Chromatography, Affinity; D002851:Chromatography, High Pressure Liquid; D003902:Detergents; D007070:Immunoglobulin A / Q000378:metabolism / Q000494:pharmacology; D008222:Lymphokines / Q000302:isolation & purification*; D008264:Macrophages / Q000276:immunology*; D008970:Molecular Weight; D017830:Octoxynol; D011092:Polyethylene Glycols; D029584:Prostatic Secretory Proteins; D051381:Rats; D011919:Rats, Inbred Strains; D011961:Receptors, Fc / Q000302:isolation & purification*; D012995:Solubility
D003902:Detergents; D007070:Immunoglobulin A; D008222:Lymphokines; D029584:Prostatic Secretory Proteins; D011961:Receptors, Fc; C043076:beta-microseminoprotein; C013059:immunoglobulin-binding factors; D011092:Polyethylene Glycols; D001710:Biotin; D017830:Octoxynol; C010615:Nonidet P-40