The present invention describes the generation of an anti-idiotype single-chain Fv (scFv) antibody specific for the murine (RFB4), chimeric (SM03) and humanized (SM06) versions of an anti-CD22 antibody (“the anti-CD22 antibodies”). The present invention further describes the construction of a murine IgG2a/kappa immunoglobulin carrying the variable region sequences of the anti-idiotype scFv sequences. Additionally, the present invention provides a cell line capable of producing an anti-idiotype murine antibody specific for “the anti-CD22 antibodies.” The present invention is directed against a method for identifying and evaluating the activities and concentration of “the anti-CD22 antibodies.” Additionally, the present invention provides a method for evaluating serum concentration of “the anti-CD22 antibodies” that are being used clinically. The present invention is also directed against a method to detect HAMA, HACA and HAHA responses in patients treated with “the anti-CD22 antibodies.” Specifically, the present invention is directed against the establishment of a cell line expressing surface concentration of the antibody of the invention； the said cell line expressing surface anti-idiotype antibodies or antibody fragments will be used as the target cell line for evaluating the functional activities of “the anti-CD22 antibodies” via complement dependent cytotoxicity (CDC) and/or antibody dependent cell cytotoxicity (ADCC) activities.
