Background: Blo t 11 is a high molecular weight allergen from Blomia tropicalis with significant immunoglobulin (Ig)E binding frequency. Native and recombinant Blo t 11 are susceptible to degradation and the isolation and expression of the allergen is problematic thus obtaining sufficient amounts of purified Blo t 11 for antibody production is limiting. DNA-based immunization is an attractive alternative strategy that bypasses antigen purification for antibody production.
Objectives: To use a DNA-based immunization protocol for the production and characterization of Blo t 11 monoclonal antibodies (mAbs).
Methods: The 2625 bp cDNA coding for Blo t 11 was cloned into a mammalian expression vector and immunized intramuscularly with electroporation into mice. Monoclonal antibodies to Blo t 11 were generated using a methylcellulose-based hybridoma cloning kit. These mAbs were utilized for native Blo t 11 isolation and the development of sandwich enzyme-linked immunosorbent assay (ELISA).
Results: Six mAbs recognizing the native and recombinant Blo t 11 were generated and characterized. Native Blo t 11 was affinity purified from Bt extract and its identity was confirmed by matrix assisted laser desorption/ionization - time of flight mass spectrometry. The native Blo t 11 showed IgE reactivity with 67% of mite allergic sera. A two-site ELISA developed showed a detection limit of 100 pg/ml of Blo t 11.
Conclusion: A DNA-based immunization protocol was successfully used to generate Blo t 11 mAbs with a spectrum of distinct epitopes located throughout the whole molecule, and they are useful for immunoaffinity purification and immunoassays.