Measurement of monoclonal antibody concentrations in hybridoma cultures: comparison of competitive inhibition and antigen capture enzyme immunoassays.

Competitive inhibition and antigen capture enzyme immunoassays were compared for the measurement of mouse monoclonal IgGl antibody produced by a hybridoma culture. Both methods yielded standard curves that were linear over several orders of magnitude, and both were comparable in sensitivity (10 ng/ml). However, the slope of the antigen capture curve was flatter than the slope for competitive inhibition. This difference in slope, coupled with a larger average standard deviation for each point on the standard curve for antigen capture, resulted in a significantly larger range of variability in IgGl levels. It is concluded that the competitive inhibition enzyme immunoassay method is better suited to the precise quantification of mouse monoclonal antibodies in hybridoma culture supernatants.

Intravenous immunoglobulin in neonatal group B streptococcal disease. Pharmacokinetic and safety studies in monkeys and humans.

Numerous studies have suggested that opsonic antibody is important in neonatal immunity to group B streptococci. Immunoglobulin G is primarily transferred from the mother to the fetus across the placenta in the last few weeks of pregnancy. Premature babies may, therefore, not acquire sufficient opsonic antibody to protect them from infection with group B streptococci. Although maternal immunization may provide adequate maternal opsonic antibody, premature infants with antibody deficiency may remain susceptible to infection. Intravenous immunoglobulin administered to term pregnant rhesus monkeys did not provide reliable levels of serum opsonic activity to group B streptococci in their offspring. Pharmacokinetic and safety studies were also performed in human neonates. Significant elevations in group B streptococcal-specific IgG did occur in human neonates given 500 mg/kg intravenous immunoglobulin and the infusions appeared safe and well tolerated. The availability of intravenous immunoglobulin with functional activity against group B streptococci may provide a rapid and effective method of delivering opsonic antibody to neonates.