Induced Proton Perturbation for Sensitive and Selective Detection of Tight Junction Breakdown

Induced Proton Perturbation for Sensitive and Selective Detection of Tight Junction Breakdown

Abstract

Tight junctions (TJs) in the epithelial cell gap play primary roles in body defense and nutrient absorption in multicellular organisms. Standard in vitro assays lack sensitivity, selectivity, temporal resolution, and throughput for bioengineering applications. Prompted by the rigorous barrier functions of TJ, we developed a TJ assay that senses proton leaks in the cell gap using ion-sensitive field-effect transistors. Upon exposure of Madin-Darby canine kidney (MDCK) cells cultured on a gate dielectric to a calcium-chelator EGTA, ammonia-assisted pH perturbation was enhanced solely in TJ-forming cells. This was supported by simulations with increased ion permeability in the paracellular pathway. Following administration of Clostridium perfringens enterotoxin as a specific TJ inhibitor to the MDCK cells, our method detected TJ breakdown at a 13× lower concentration than a conventional trans-epithelial electrical resistance assay. Thus, the semiconductor-based active pH sensing could offer an alternative to current in vitro assays for TJs in pathological, toxicological, and pharmaceutical studies.

Journal Article

JOURNAL:
Analytical Chemistry

TITLE:
Induced Proton Perturbation for Sensitive and Selective Detection of Tight Junction Breakdown

DOI:
https://doi.org/10.1021/acs.analchem.8b05237

Correspondence to

Tatsuro GODA, Ph.D., Assistant Professor
Department of Bioelectronics,
Institute of Biomaterials and Bioengineering,
Tokyo Medical and Dental University(TMDU)
E-mail:goda.bsr(at)tmd.ac.jp