Optimized Protocol for Assessing Tight Junction Integrity and Claudin Expression in Human Epidermal Keratinocytes

Area of Science:

• Dermatology
• Cell Biology
• Biophysics

Background:

• Tight junctions are crucial for epidermal barrier function, regulated by claudin proteins.
• Dysfunctional tight junctions are linked to skin diseases and impaired healing.
• Standardized methods for assessing tight junctions in keratinocytes are lacking.

Purpose of the Study:

• To develop and validate a reproducible workflow for evaluating tight junction integrity and claudin expression in cultured human epidermal keratinocytes.
• To provide a reliable platform for skin barrier research and disease modeling.

Main Methods:

• Combined assessment using transepithelial electrical resistance (TEER) for barrier function.
• Fluorescent tracer assays for paracellular permeability and immunofluorescence microscopy for protein localization.
• Western blotting and real-time PCR for quantitative claudin expression analysis.

Main Results:

• The described workflow integrates functional and molecular assessments of tight junctions.
• Key variables like calcium switch and differentiation status were optimized for reproducibility.
• The protocol enables robust spatial and quantitative analysis of tight junction proteins.

Conclusions:

• This optimized protocol offers a reliable method for studying epidermal tight junction dynamics.
• The workflow supports investigations in skin barrier research, toxicology, and therapeutic evaluations.
• Standardized assessment of tight junctions is essential for understanding skin health and disease.