AN AFFINITY COLUMN METHOD FOR DETERMINATION OF THE IMMUNOREACTIVITY OF I-131 CHIMERIC L6 MONOCLONAL-ANTIBODY AND COMPARISON TO IN-VIVO TUMOR-LOCALIZATION
Em. Jagoda et al., AN AFFINITY COLUMN METHOD FOR DETERMINATION OF THE IMMUNOREACTIVITY OF I-131 CHIMERIC L6 MONOCLONAL-ANTIBODY AND COMPARISON TO IN-VIVO TUMOR-LOCALIZATION, Journal of immunological methods, 173(2), 1994, pp. 191-201
An affinity column method was developed to determine the immunoreactiv
ity of I-131-ChiL6 (chimeric L6 monoclonal antibody), a candidate for
radioimmunotherapy. This method involved assessing the binding of the
radiolabeled antibody to antigen containing membranes bound to a React
i-gel agarose matrix. The immunoreactivity determined by the affinity
column method correlated to other in vitro binding assays including th
e Lindmo infinite antigen excess method. In tumor-bearing mice which h
ad been injected with I-131-ChiL6, which possessed high immunoreactivi
ties (90-82%), a high tumor uptake (13.5-10.5% ID/g) was observed. A d
ecrease in tumor uptake (5.2-4.8% ID/g) was observed with I-131-ChiL6
samples of low immunoreactivity (42% and 31%, respectively). While a m
oderate loss of immunoreactivity (4-18%) of the I-131-ChiL6 samples co
uld be detected by the affinity column method, the loss of tumor uptak
e in vivo observed was not as significant. This method was found to be
an efficient and sensitive method for detecting damage to the antibod
y during radiolabeling and applicable as a quality control method for
clinical trials. This rapid method, compared to the other in vitro bin
ding assays (including the Lindmo infinite antigen excess method) has
distinct advantages as a quality control method since it requires less
manipulation and can be semi-automated.