With the ever-growing use of multiplex assays in research, therapeutics, and diagnostics, the need to conjugate antibodies to dyes, enzymes, and other materials is increasing. While there are many challenges to overcome regarding conjugation, the largest hurdle is maintaining antibody activity after conjugation. To combat these conjugation challenges, AlphaThera developed a conjugation system that utilizes a small adapter protein to label antibodies quickly and site-specifically, resulting in antibodies that maintain their activity post-conjugation.
The adapter protein contains a customizable C- terminal region that can be modified to contain diverse labels including fluorescent dyes, click-chemistry, drugs, and epitope tags. Incorporating the epitope tag conjugation system with Fortis Life Sciences anti-epitope tag detection antibodies, we developed an easy and adaptable system for generating conjugated antibodies to use in multiplex assays. We used this system to detect staining of multiple markers including CD3, Granzyme B, PCNA, and actin via flow cytometry, IHC, ICC, and western blot.
One of the tested antibodies retained normal activity post-conjugation even though prior attempts with metal tagging via sulfhydryl groups resulted in lost activity. The vast array of conjugated anti-epitope tag antibodies allows for the selection of specific dyes/materials that are optimized to your desired assays. Additionally, since the secondary antibody is detecting the epitope tag, multiplexing is simplified, and antibody host is rendered irrelevant. This epitope tag system provides a simple, site-specific conjugation method that has incredible adaptability for any multiplex assay.