Multicellular Human Alveolar Model Composed of Epithelial Cells and Primary Immune Cells for Hazard Assessment

Area of Science:

• * In vitro toxicology and immunology
• * Cellular and tissue modeling

Background:

• * Accurate simulation of the human alveolar epithelial barrier is crucial for studying lung responses to inhaled substances.
• * Existing models often lack the complexity of native lung tissue, particularly regarding immune cell interactions.

Purpose of the Study:

• * To develop and validate a three-dimensional human alveolar coculture model.
• * To assess the model's responsiveness to proinflammatory stimuli.
• * To compare immune cells derived from fresh versus thawed monocytes.

Main Methods:

• * Established a coculture of alveolar epithelial type II cells (A549), monocyte-derived macrophages (MDMs), and dendritic cells (MDDCs).
• * Utilized a protocol involving submerged culture followed by air-liquid interface exposure.
• * Compared immune cells differentiated from fresh or thawed peripheral blood monocytes (PBMs).

Main Results:

• * The 3D alveolar coculture model demonstrated a significant increase in cytokine release (IL-6, IL-8) upon exposure to lipopolysaccharide and TNF-α.
• * No significant difference in cytokine release was observed between cocultures using fresh or thawed monocytes.
• * The model showed consistent responsiveness to proinflammatory stimuli.

Conclusions:

• * The developed human alveolar coculture model effectively simulates the alveolar epithelial tissue barrier.
• * The model is a robust tool for investigating acute biological responses to various inhaled substances, including drugs and nanomaterials.
• * The model's utility is confirmed with both fresh and thawed monocyte-derived immune cells.