Monoclonal antibodies to human IgG: reaction characteristics in the centrifugal analyzer.

We used monoclonal antibodies to human IgG in a kinetic turbidimetric method with a centrifugal analyzer. Results for total IgG with monoclonal and polyclonal reagents correlated well (r = 0.979). Within- and between-batch CVs compared favorably (3.1 and 4.8%, respectively, for polyclonal antisera and 3.5 and 4.0%, respectively, for monoclonal reagents). The monoclonal antibody combination used was shown to be of high titre, with an avidity toward the lower end of the range seen with conventional antisera to IgG. It displayed reaction characteristics similar to those observed with polyclonal antisera, although the time scale of reaction was extended and the effective concentration range was narrowed. Single monoclonal antibodies may not produce complexes of a size exhibiting measurable turbidity when reacted with soluble antigen. However, evidence is presented for the incorporation of such complexes into precipitates produced by other related antigen-antibody systems.