Pneumococcal Opsonophagocytosis Assays
Protective Capacity of Antibodies
Category: Vaccines | Immunology
New Analytical Approaches for Measuring Protective Capacity of Antibodies
from Moon H. Nahm and Carl E. Frasch writing in Vaccine Design: Innovative Approaches and Novel Strategies
Antibodies to the pneumococcal polysaccharide capsule protect the host by opsonizing pneumococci for host phagocytes, while antibodies to the meningococcal polysaccharide capsule protect by directly killing meningococci in the presence of complement. In vitro measurement of serum bactericidal antibody (SBA) against the meningococcus has been used for a long time as a measure of protective immunity. Technical developments of pneumococcal opsonophagocytosis assays (OPA) in the past decade permit measurements of opsonic capacity of sera from persons immunized with pneumococcal vaccines. Experience with OPAs shows that opsonic capacities of antisera are better than their antibody levels in predicting vaccine efficacy. Thus, measurements of opsonic capacity could be a surrogate of clinical studies of pneumococcal vaccines. By being the surrogate for clinical studies, the assays for protective function of antibodies would reduce the need for large clinical trials and facilitate vaccine developments and improvements.
Further reading: Vaccine Design: Innovative Approaches and Novel Strategies
from Moon H. Nahm and Carl E. Frasch writing in Vaccine Design: Innovative Approaches and Novel Strategies
Antibodies to the pneumococcal polysaccharide capsule protect the host by opsonizing pneumococci for host phagocytes, while antibodies to the meningococcal polysaccharide capsule protect by directly killing meningococci in the presence of complement. In vitro measurement of serum bactericidal antibody (SBA) against the meningococcus has been used for a long time as a measure of protective immunity. Technical developments of pneumococcal opsonophagocytosis assays (OPA) in the past decade permit measurements of opsonic capacity of sera from persons immunized with pneumococcal vaccines. Experience with OPAs shows that opsonic capacities of antisera are better than their antibody levels in predicting vaccine efficacy. Thus, measurements of opsonic capacity could be a surrogate of clinical studies of pneumococcal vaccines. By being the surrogate for clinical studies, the assays for protective function of antibodies would reduce the need for large clinical trials and facilitate vaccine developments and improvements.
Further reading: Vaccine Design: Innovative Approaches and Novel Strategies