Cockroach extract antigen increases bronchial airway epithelial permeability

Area of Science:

• Immunology and Allergy
• Respiratory Medicine
• Environmental Health

Background:

• Bronchial epithelial cells face constant environmental damage.
• Inner-city children exhibit a high incidence of asthma.
• Cockroach allergens are implicated as a contributing factor to childhood asthma.

Purpose of the Study:

• To determine if cockroach extract antigen (CrAg) induces vascular endothelial growth factor (VEGF) production.
• To investigate if CrAg increases permeability in bronchial airway epithelial cells (BAECs).

Main Methods:

• Enzyme-linked immunosorbent assay (ELISA) to quantify VEGF release.
• Reverse transcription polymerase chain reaction (RT-PCR) to assess VEGF mRNA expression.
• Electric cell substrate impedance sensing (ECIS) to measure changes in BAEC barrier function (electrical resistance).

Main Results:

• CrAg stimulated a time-dependent release of VEGF in BAECs.
• VEGF mRNA expression was upregulated in CrAg-exposed BAECs.
• CrAg significantly reduced electrical resistance across BAEC monolayers, indicating increased permeability, an effect reversed by anti-VEGF antibodies.

Conclusions:

• Cockroach extract antigen induces VEGF release in bronchial airway epithelial cells.
• CrAg exposure alters bronchial airway permeability, potentially contributing to asthma pathogenesis.