Abstract:

To prepare and identify monoclonal antibody(McAb) against ochratoxin A（OA）and to establish a competitive inhibition ELISA method for detection of OA. MethodsUsing a lowdose and longcycle immunization scheme, female BALB/c mice were immunized with OA coupled to bovine serum albumin(OABSA). Hybridoma cell lines secreting McAbs against OABSA were obtained by cell fusion. The specifcity of McAbs to OA was further analyzed by a competition inhibition test. A large amount of McAbs was made by ascites in liquid paraffinprimed mice. A competition inhibition ELISA method using OA as a competitive antigen was established to monitor OA. ResultsTiter of McAbs in the sera from BALB/c mice immunized by OABSA was 1:512?000 and it had a strong cross reaction with BSA. Hybridoma cell lines which secreted McAbs against OABSA were screened by ELISA after cell fusion. The crossreactive rate of McAbs against OA and BSA was 3.5%.  Hybridoma cell lines secreting McAbs against OABSA were completely established by 3 rounds of cell subcloning, and the specificity of McAbs for OA was further confirmed by competition inhibition ELISA. A large amount of McAbs was obtained by ascites production. The linear range of the competitive inhibition ELISA was 0.24125?ng/mL, the linear regression equation was y=-0.113?2logx+0.901?6, the linear correlation was 0.98, and the detection limit was 0.24?ng/mL. Recovery rate for the sample ranged from 97.07% to 107.8%. ConclusionHybridoma cell lines secreting McAbs against ochratoxin A were obtained and a simple and sensitive efficient method for OA determination was established.

Key words: Ochratoxin A； Monoclonal antibody； Cell fusion； ELISA