Haemophilus influenzae type b opsonins of intravenous immunoglobulins.

Immunoglobulin G may be prepared by different methods for intravenous infusion and administered as replacement therapy for hypogammaglobulinemia. Intravenous immunoglobulins prepared by different methods were compared in vitro for their ability to opsonize Haemophilus influenzae type b in the absence of complement and subsequently induce neutrophil chemiluminescence. While the antibody contents, measured by an enzyme-linked immunosorbent assay and radioimmunoassay, were equivalent, the immunoglobulin prepared by a non-molecular modifying method (ion-exchange chromatography) had the greatest ability to induce bacterial-neutrophil interaction, measured by chemiluminescence, while a reduced and alkylated immunoglobulin had the least. Thus, preparative methods may have a profound effect upon the function of intravenous immunoglobulins. The biological function of immunoglobulins for clinical use can be compared easily by neutrophil chemiluminescence.