Procedure and diagnostics for the qualitative or quantitative detection of antibodies and for the determination of their Avidity

摘要

Method for quantitative or qualitative determination of an antibody (Ab) by reaction with its cognate antigen (Ag), selective destabilization of complexes formed with Ab of low affinity and measuring the degree of Ab-Ag binding. The new feature is that the protein denaturant (I) used is adjusted to a pH outside the normal range (5-9) for immunological assays. Independent claims are also included for: (1) method for determining the affinity of Ab; (2) method for differentiating early and late infections using the method of (1); (3) method for detecting acute or recent measles infection, first infection by cytomegalovirus, Epstein-Barr virus or herpes simplex virus, or Toxoplasma gondii infection; (4) wash or sample dilution buffers for immunoassays adjusted to pH outside the range 5-9; and (5) diagnostic composition for performing the new processes.