Characterization of an immune response.

The characterization of any detected antibodies provides detailed information that can be critical to understanding the significance of an immune response. The BIAcore immunoassay provides a straightforward means of characterizing many aspects of the immune response including antibody concentration, specificity, binding affinity, and the presence of isotypes. One important aspect of the immune response is determination of neutralizing capability, which requires a biological assay. The ultimate clinical significance of an immune response can only be fully understood when data from antibody characterization are coupled with clinical data from the patient. Some of the factors that can contribute to the clinical significance of an immune response are: (i) magnitude of the immune response (concentration of antibodies detected); (ii) duration of the immune response (continuous antibody production or sporadic and not sustained); (iii) correlation with any adverse events; (iv) correlation with a change in pharmacokinetics (either mediating sustained circulation or enhanced clearance of the drug); (v) biological neutralization of the drug; (vi) biological neutralization of an endogenous protein. Full characterization of the immune response requires the incorporation of antibody assays, pharmacokinetic assays, and clinical data.