Air-liquid interface (ALI) impact on different respiratory cell cultures

Area of Science:

• Respiratory physiology
• Cell biology
• Drug delivery systems

Background:

• Intranasal drug delivery is gaining traction for systemic, pulmonary, and neurological treatments.
• In vitro models struggle to replicate human respiratory physiology, limiting the reliability of drug transport and permeability studies.
• The air-liquid interface (ALI) method shows promise for enhancing airway epithelium cell differentiation and morphology.

Purpose of the Study:

• To review and evaluate airway epithelium cell models used with the air-liquid interface (ALI) method.
• To assess how ALI conditions affect different cell types and models.
• To provide insights into optimizing ALI models for pharmacological and toxicological studies.

Main Methods:

• Review of existing literature on air-liquid interface (ALI) methodologies for airway epithelium.
• Evaluation of cellular features before and after ALI exposure in various models.
• Analysis of ALI model applications in primary cells, cell lines, 3D models, and stem-cell derived models.

Main Results:

• ALI conditions promote cell differentiation and improve morphological characteristics of airway epithelium cells compared to submerged cultures.
• Various ALI methodologies and materials exist, but a lack of consensus on validation hinders data comparison.
• ALI models have been applied in recent pharmacological studies, including those targeting SARS-CoV-2.

Conclusions:

• The air-liquid interface (ALI) method offers a superior in vitro approach for studying airway epithelium.
• Optimization of ALI conditions must consider cell type (nasal, bronchial, alveolar), origin, and study objectives.
• ALI models are valuable tools for inhalation toxicology and complement in vivo experiments, aiding drug development.