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Published on: January 21, 2018
Temporal patterns of mediator release during developing cutaneous late-phase reactions.
1Department of Medicine, Division of Allergy and Immunology, University of Pennsylvania School of Medicine, Philadelphia, PA, USA.
Summary
Cutaneous late phase reactions involve rapid inflammatory mediator release and immune cell activation. Histamine, lactoferrin, and eosinophil cationic protein are released early, contributing to skin inflammation.
Area of Science:
- Immunology
- Dermatology
- Allergy Research
Background:
- Cutaneous late phase reactions (LPR) involve inflammatory mediators.
- The precise timing of mediator release during LPR development remains unclear.
Purpose of the Study:
- To chronologically map mediator release during LPR.
- To correlate mediator release with inflammatory cell responses and gross LPR development.
Main Methods:
- Utilized skin chambers for hourly sample collection following allergen challenge.
- Analyzed exuded leukocytes for activation and mediator content.
Main Results:
- Histamine release peaked within the first hour post-allergen challenge.
- Neutrophil-derived lactoferrin and eosinophil cationic protein release followed, associated with IL-8.
- A higher percentage of activated leukocytes was observed in allergen-challenged sites.
Conclusions:
- Skin inflammatory responses, including leukocyte activation and mediator release, commence shortly after initial mast cell activation in IgE-mediated reactions.
- These findings elucidate the temporal dynamics of LPR development.
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