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bioRxiv · 10.1101/2022.05.09.491123

Chemoenzymatic fluorescence labeling of intercellularly contacting cells using lipidated sortase A

Yamaguchi, S.·Ikeda, R.·Umeda, Y.·Kosaka, T.·Yamahira, S.·Okamoto, A.
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Abstract

Methods to label intercellular contact attract particular attention due to their potential in cell biological and medical applications through analysis of intercellular communications. In this study, a simple and versatile method for chemoenzymatically labeling the intercellularly contacting cell was developed by using a cell-surface anchoring reagent of poly(ethylene glycol)(PEG)-lipid conjugate. The surfaces of each cell in cell pairs of interest were efficiently decorated with sortase A (SrtA) and triglycine peptide that were lipidated with PEG-lipid, respectively. In the mixture of the two cell populations, the triglycine-modified cells were enzymatically labeled with a fluorescent labeling reagent by contacting with the SrtA-modified cells both on the substrate and in cell suspensions. Such selective labeling of the contacting cells was confirmed by confocal microscopy and flow cytometry. The results show a proof of principle that the present method is a promising tool for selective visualization and quantification of the intercellularly contacting cells among cell mixtures in cell-cell communication analysis.

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Yamaguchi, S., Ikeda, R., Umeda, Y., Kosaka, T., Yamahira, S., Okamoto, A.. 2022-05-09. Chemoenzymatic fluorescence labeling of intercellularly contacting cells using lipidated sortase A. https://doi.org/10.1101/2022.05.09.491123

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