Bovine serum albumin as an immunogenic carrier facilitating the development of hapten-specific monoclonal antibodies

There is a common misconception that the generation of hapten-specific monoclonal antibodies (mAbs) requires the use of a heterologous conjugate to ensure carrier-specific antibodies not being detected. In this study, salbutamol (SAL) was used as a model hapten to exhibit the benefits of bovine serum albumin (BSA) as a carrier for developing hapten-specific mAbs. SAL-BSA conjugate would serve as both an immune antigen and a screening antigen during the preparation of SAL-specific mAbs. Six hybridomas were identified to secret mAbs specific for free SAL with minor or negligible cross-reactivity with other {beta}-agonists. Meanwhile, none of hybrodomas secreting anti-BSA antibodies were screened out even though the fetal bovine serum (FBS) added to the medium decreased from 10% to 1% (v/v). Based on one of the six mAbs, 3F12, a direct competitive enzyme-linked immunosorbent assay (dcELISA) was developed for meausring SAL. Under the optimized assay, the quantitative working range was from 312.5 to 20,000 pg/mL (R2 = 0.9959), with a limit of detection (LOD) of 142.9 pg/mL. The results showed that BSA is an efficient and suitable protein carrier for facilitating the development of hapten-specific mAbs.