Transepithelial Electrical Resistance Measurement

Resistance values provide an indirect readout of junctional tightness. When epithelial cell-cell junctions become tighter, fewer ions move through the paracellular route, generally producing a higher measurement. A lower value instead suggests greater ion movement between cells and a less restrictive barrier. This interpretation lets investigators track functional changes without relying only on visible changes in the cultured layer.

The small electrical signal is important because it probes ionic passage without requiring a destructive assay. Applied across the monolayer, it generates a measurable response that reflects resistance to ion movement across the epithelial arrangement. Because the cells sit on a permeable support, the measurement is oriented across the barrier, making it useful for examining cell-cell junction function in a controlled culture model.

Tracking measurements over time allows investigators to separate major barrier states. An increasing value can accompany barrier formation or recovery, while a decreasing value can indicate disruption, because the resistance generally rises when junctions become tighter and falls when paracellular ion movement increases. This makes TEER useful for following dynamic changes rather than a single endpoint.

Researchers first grow an epithelial cell monolayer on a permeable support, then apply a small electrical signal across that layer and record the resulting resistance. Repeating the measurement during culture or experimental treatment allows them to monitor whether the barrier forms, becomes disrupted, or recovers. The workflow therefore links a defined cell model to a functional barrier readout.

TEER is useful when a study needs to follow epithelial barrier behavior in models of the intestine, skin, airway, or blood-brain barrier. It can support investigations of disease mechanisms, drug permeability, toxicity, and the development of more predictive in vitro tissue models. Its value comes from connecting barrier integrity with a measurable electrical outcome in cultured cells.

By reporting resistance across a cultured epithelial layer, the method helps researchers assess whether a model behaves as a restrictive barrier and how that state changes during testing. This supports drug-permeability and toxicity studies while also informing efforts to build more predictive in vitro tissues. The result is functional evidence that complements the model’s intended medical application.