AFFINITY - A SOFTWARE PACKAGE FOR CALCULATION OF ANTIBODY-AFFINITY BYENZYME-LINKED-IMMUNOSORBENT-ASSAY (ELISA)

We have developed a general strategy and a versatile computer program for the analysis of data from ELISA experiments. This program provides a least squares estimates of binding parameters (affinity constants) of monoclonal antibodies. A simple and reliable method based upon law of mass action for calculation affinity of monoclonal antibodies using non-competitive ELISA was applied. The binding of an antibody with an antigen is measured using serial dilutions of both antigen (coated on the plate) as well as antibody. When the optical density measured aft er the antigen-antibody interaction was plotted against the concentrat ion of antibody, added to the wells, a sigmoidal curve was obtained. T he optical density at any point of the curve, was considered as a dire ct reflection of the amount of antibody bound to the antigen. A linear dose-response curve could be obtained by use of a 'sigmoidal' or 'S-s haped' transformation of the response variable. The legit-log transfor mation is used to test the validity of this method and the affinity co nstant for this monoclonal antibody was calculated.