Development of a mouse-feline chimeric antibody against feline tumor necrosis factor-alpha

DOKI, Tomoyoshi; TAKANO, Tomomi; HOHDATSU, Tsutomu

To investigate whether there were neutralizing antibodies against mouse and chimeric mAb 2-4 in mAb treated cat serum, the collected sera were reacted with mouse mAb 2-4 or chimeric mAb 2-4, and changes in the fTNF-alpha neutralization activities of these antibodies were measured. When mouse mAb 2-4 was reacted with sera from cats treated with 1 or 5 mg/kg mouse mAb 2-4, its neutralizing activity was decreased (Fig. 4A ), but when it was reacted with serum from PBS-treated cats, no decrease in the neutralizing activity was observed. When chimeric mAb 2-4 was reacted with serum from cats treated with 1 mg/kg chimeric mAb 2-4, no decrease in the neutralizing activity of chimeric mAb 2-4 was observed, similarly to that observed when reacted with serum of PBStreated cats (Fig. 4B) . Regarding serum from cats treated with 5 mg/kg of chimeric mAb 2-4, the neutralizing activity of chimeric mAb 2-4 decreased when it was reacted with sera collected after the 3rd administration and thereafter (28 days after the initial administration) (Fig. 4B) .