Activation of human monocytes via their sIgA receptors.
We have studied the interaction of secretory immunoglobulin A (sIgA) derived from human breast milk with human monocytes. The presence of specific sIgA receptors on the monocyte membrane was confirmed by dose-dependent inhibition of E-sIgA rosette formation and by the binding of iodinated sIgA to monocyte monolayers. Binding was dependent on both the number of monocytes, as well as the amount of [125I]sIgA, and could be inhibited by unlabelled sIgA. Incubation of monocyte monolayers in the presence of increasing concentrations of secretory IgA and F(ab')2 anti-IgA resulted in a dose-dependent increase of the oxidative burst, as measured by H2O2 production. Neither sIgA or anti-IgA alone, nor incubation of IgG with anti-IgA, had any effect on the oxidative burst. These studies indicate that human monocytes have a receptor for sIgA and that specific activation of the monocytes occurs via these receptors.
Padeh
S
S
Samuel Jared Kushnick Pediatric Immunology Laboratory, Sheba Medical Center, Sackler School of Medicine, Rehovot, Israel.
Jaffe
C L
CL
Passwell
J H
JH
D000936:Antigen-Antibody Complex / Q000276:immunology; D015232:Dinoprostone / Q000096:biosynthesis; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D007071:Immunoglobulin A, Secretory / Q000276:immunology* / Q000378:metabolism; D009000:Monocytes / Q000276:immunology* / Q000378:metabolism; D011961:Receptors, Fc; D011971:Receptors, Immunologic / Q000276:immunology*; D012397:Rosette Formation
D000936:Antigen-Antibody Complex; C068317:IgA, secretory receptor; D007071:Immunoglobulin A, Secretory; D011961:Receptors, Fc; D011971:Receptors, Immunologic; D006861:Hydrogen Peroxide; D015232:Dinoprostone