title: Neutrophil chemiluminescence induced by opsonized group A streptococcal particles: an effective probe of intravenous immunoglobulin preparations.
abstract: We compared the capacity of eight different intravenous immunoglobulin (IVIG) preparations to opsonize streptococcal group A particles and to induce luminol-enhanced chemiluminescence in neutrophil granulocytes. Antibodies to the streptococcal group A carbohydrate (A-CHO) antigen exposed on the particles were present in all preparations at high concentrations. In some preparations, anti-A-CHO consisted predominantly of either immunoglobulin G1 (IgG1) or IgG2, whereas in others, both IgG subclasses were equally represented. Dilutions of the IVIGs and of a normal IgG reference preparation were adjusted for their anti-A-CHO content, incubated with streptococcal particles, and exposed to neutrophil granulocytes isolated from normal blood. The various IVIGs differed in their capacity to elicit chemiluminescence signals. Some preparations, particularly those consisting of chemically modified IgG molecules, showed little activity, whereas others were comparable to the reference preparation. We concluded that to some extent such differences could be related to the IgG subclass composition of the antibody. However, of greater importance were the manufacturing procedures by which both the antigen-binding fragment and crystallizable fragment portions, and thus the functional integrity of the IgG molecules, were more or less severely affected.
authors.affiliation: Institute for Clinical and Experimental Cancer Research, University of Bern, Switzerland.
authors.forename: R
authors.initials: R
authors.lastname: Rüfenacht
authors.forename: P
authors.initials: P
authors.lastname: Chase
authors.forename: T W
authors.initials: TW
authors.lastname: Jungi
authors.forename: A
authors.initials: A
authors.lastname: Morell
mesh_terms: D006801:Humans; D007116:Immunization, Passive; D007140:Immunoglobulin Fab Fragments / Q000276:immunology; D007141:Immunoglobulin Fc Fragments / Q000276:immunology; D007074:Immunoglobulin G / Q000276:immunology*; D008163:Luminescent Measurements; D009504:Neutrophils / Q000502:physiology*; D010587:Phagocytosis; D013297:Streptococcus pyogenes / Q000276:immunology*
chemical_list: D007140:Immunoglobulin Fab Fragments; D007141:Immunoglobulin Fc Fragments; D007074:Immunoglobulin G