Mechanisms for adherence of eosinophils to an antibody-coated surface.
Eosinophils may act by degranulation after attachment to a surface. As the mechanisms of adherence are not understood, we have investigated the dependency on Fc(IgG) receptors and other mechanisms by studying the adherence of human eosinophils to albumin-Sepharose beads coated with either specific rabbit IgG antibody, F(ab')2 antibody fragments or serum under different conditions. Adherence to Sephadex beads and albumin-coated microtitration plates was also investigated. 50% of the eosinophils adhered spontaneously to all 3 different surfaces not coated with the antibody, whereas only 25% of neutrophils and less than 10% of mononuclear cells adhered. A small but significant increase in adherence to albumin-Sepharose or albumin-coated plastic occurred after addition of the IgG-antibody, but not after addition of F(ab')2 fragments, indicating that the Fc region was responsible for some increase in adherence. Incubation of eosinophils with IgG-Fc fragments prevented the additional antibody-mediated adherence. As Fc receptor-negative eosinophils adhered almost as well as Fc receptor-positive cells, it appears that the Fc receptors are of minor importance and instead, a nonspecific adherence mechanism, possibly unique for the eosinophil, seems to be the most important in eosinophil adherence to antibody-coated surfaces.
Winqvist
I
I
Olofsson
T
T
Olsson
I
I
D000818:Animals; D000936:Antigen-Antibody Complex / Q000276:immunology; D002448:Cell Adhesion / Q000187:drug effects; D003571:Cytochalasin B / Q000494:pharmacology; D003911:Dextrans; D004804:Eosinophils / Q000187:drug effects / Q000502:physiology*; D004912:Erythrocytes / Q000276:immunology; D006801:Humans; D007074:Immunoglobulin G / Q000378:metabolism; D066298:In Vitro Techniques; D011961:Receptors, Fc / Q000502:physiology; D012397:Rosette Formation / Q000379:methods; D012685:Sepharose; D012709:Serum Albumin / Q000276:immunology; D012756:Sheep; D013696:Temperature; D014357:Trypsin / Q000494:pharmacology
D000936:Antigen-Antibody Complex; D003911:Dextrans; D007074:Immunoglobulin G; D011961:Receptors, Fc; D012709:Serum Albumin; D003571:Cytochalasin B; D012685:Sepharose; C025614:sephadex; D014357:Trypsin