Diversification of the recombinant anti-kinesin monoclonal antibody H2

Niwa, S.; Chiba, K.

doi:10.1101/2022.12.22.521561

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bioRxiv · 10.1101/2022.12.22.521561

Diversification of the recombinant anti-kinesin monoclonal antibody H2

Niwa, S.·Chiba, K.

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Abstract

Kinesin-1, a motor protein composed of the kinesin heavy chain (KHC) and the kinesin light chain (KLC), is fundamental to cellular morphogenesis and function. A monoclonal antibody (mAb) called H2 recognizes the KHC in a broad range of species and is one of the most widely used mAbs in cytoskeletal motor research. Here, we generated vectors that expressed recombinant H2 in mammalian cells. We demonstrated that the recombinant H2 performed as well as the hybridoma-derived H2 in western blotting and immunofluorescence assays. The recombinant H2 could detect all three human KHC isotypes (KIF5A, KIF5B, and KIF5C) and amyotrophic lateral sclerosis (ALS)-associated KIF5A aggregates in the cell. Immunofluorescence microscopy showed that the single chain variable fragment (scFv) derived from the H2 mAb could specifically recognize KHCs in cells. In addition, we developed a chickenized anti-KHC scFv(H2), which broadens the application of H2 in immunofluorescence microscopy. Collectively, our findings validate recombinant H2 as useful for studying the function of KHCs.

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Niwa, S., Chiba, K.. 2022-12-22. Diversification of the recombinant anti-kinesin monoclonal antibody H2. https://doi.org/10.1101/2022.12.22.521561

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