Anchored cell analysis/sorting coupled with the scrape‐loading/dye‐transfer technique to quantify inhibition of gap‐junctional intercellular communication in WB‐F344 cells by 2,2',4,4' ,5,5'‐hexabromobiphenyl

Abstract

Inhibition of intercellular communication has been hypothesized to play a role in tumor promotion. The compound 2,2’,4,4’,5,5'‐hexabromobiphenyl (245‐HBB) is a tumor prompter in vivo and blocks intercellular communication in vitro. The scrape‐loading/dye‐transfer (SL/DT) assay was used to assess this in vitro effect at varying concentrations of 245‐HBB. The SL/DT technique is based on the intracellular loading of a fluorescent dye, lucifer yellow (LY), and monitoring its transfer into adjacent cells via patent gap junctions. Confluent WB‐F344 (rat epithelial) cells were exposed to various noncytolethal concentrations of 245‐HBB. Transfer of LY was then quantified with anchored cell analysis/sorting (ACAS 470, Meridian Instruments, Okemos, Mich.). The results indicate an inverse correlation between the degree of fluorescence in secondary LY‐recipient cells and the treatment concentration. The coupling of these two new methods of cellular biology provided rapid quantitative analysis of dye transfer in measuring the concentration/response of modulation of gap‐junctional permeability in cultured cells.