Static Adhesion Assay for Human Peripheral Blood Mononuclear Cells.

Area of Science:

• Immunology
• Cell Biology
• Vascular Biology

Background:

• Blood endothelial cells (ECs) form a barrier crucial for leukocyte transmigration during inflammation.
• Leukocyte adhesion and transmigration are key steps in immune responses.
• Existing transmigration assays have limitations in assessing EC functionality and cell recovery.

Purpose of the Study:

• To describe a novel in vitro static adhesion assay for evaluating the firm adhesion of peripheral blood mononuclear cells (PBMCs) to endothelial cells (ECs).
• To enable quantitative and qualitative analysis of PBMC adhesion to ECs under specific stimulation conditions.
• To facilitate functional studies on EC biology with improved EC recovery.

Main Methods:

• Primary human umbilical cord ECs (HUVECs) were pre-incubated with innate lymphoid cell progenitors (ILCPs) or tumor necrosis factor (TNF).
• Total PBMCs were added to assess adherence to pre-treated HUVECs.
• The assay allows for quantitative and qualitative analysis of adhered PBMC subtypes and numbers.
• ECs can be recovered post-assay for further functional studies.

Main Results:

• The assay successfully quantifies and characterizes PBMC adhesion to stimulated ECs.
• Upregulation of adhesion molecules on ECs by ILCPs or TNF enhances PBMC retention.
• The method allows for detailed analysis of cellular subtypes involved in adhesion.

Conclusions:

• This static adhesion assay provides a valuable tool for studying EC-PBMC interactions in vitro.
• It allows interrogation of how different stimulations and cell types influence ECs' ability to retain PBMCs.
• The assay's advantage lies in its ability to recover ECs for subsequent functional analyses, unlike transwell systems.