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

Abstract

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 β-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.

Monoclonal Antibodies Application in Lateral Flow Immunochromatographic Assays for Drugs of Abuse Detection

“…They are used as haptens or as a recognition site for the production of specific Abs by coupling them to a suitable carrier molecule (the immune response in the host animal can produce Abs against the entire immunogen and not just the drug molecule). Many proteins can be used as carriers, but the most commonly used ones are bovine serum albumin (BSA; 67 kDa) and keyhole limpet hemocyanin (KLH, 400 kDa), which are highly immunogenic because of their complexity (structure) and large sizes [ 32 , 33 , 34 , 35 ].…”

“…BSA is widely used as a blocking agent in development of immunoassays, such as ELISA and LFIA, because it is very accessible and available and has numerous useful groups to be linked to small molecules, including DOA, as a carrier molecule to induce the immune system. For this reason, it is recommended, for example, to use KLH as the carrier molecule (protein) to induce an immune response against the hapten and the BSA for Abs screening and purification, to assure the detection of the Ag (hapten) instead of the carrier Abs [ 32 , 33 , 35 ].…”

Shrimp Hemocyanin elicits a potent humoral response in mammals and is favorable to hapten conjugation

“…For the generation of antibodies against hapten or the hapten vaccine, three carrier proteins were used for covalent conjugation, e.g. KLH (Keyhole Limpet Hemocyanin ), BSA (Bovine Serum Albumin) and OVA (Ovalbumin) (6). BSA and KLH could induce a strong immune response, while OVA is less effective and its solubility is not as high as the others (7).…”