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Histamine metabolism in delayed type hypersensitivity--comparative analysis with cellular infiltrates.
T Tachibana1, K I Toda, F Furukawa
1Department of Dermatology, Faculty of Medicine, Kyoto University, Japan.
Archives of Dermatological Research
|January 1, 1990
Summary
Histamine levels rise in delayed type hypersensitivity (DTH) skin reactions, correlating with infiltrating basophils, not mast cells. Basophil degranulation varies, but their presence drives histamine increase in DTH.
Area of Science:
- Immunology
- Dermatology
- Histamine Metabolism
Background:
- Cutaneous delayed type hypersensitivity (DTH) involves complex immune responses.
- Histamine is a key mediator in allergic and inflammatory reactions.
- Understanding histamine dynamics in DTH is crucial for therapeutic development.
Purpose of the Study:
- To investigate the dynamic changes in histamine concentration and immune cell infiltration in various DTH models.
- To determine the relationship between histamine levels and specific immune cell populations, particularly basophils and mast cells.
- To explore differences in basophil behavior and histamine release mechanisms across different DTH reactions.
Main Methods:
- Induction of DTH models: dinitrochlorobenzene (DNCB) allergic dermatitis, purified protein derivative of tuberculin (PPD) reaction, and keyhole limpet hemocyanin (KLH)-induced cutaneous basophil hypersensitivity.
- Quantification of histamine concentration in lesional sites over time.
- Analysis of infiltrating immune cell populations (mast cells and basophils) via histology.
- Assessment of histamine-degrading enzyme activity.
Main Results:
- Histamine concentration significantly increased in all DTH models, with varying time courses.
- KLH-induced DTH showed a markedly higher histamine peak earlier than DNCB or PPD models.
- Basophil infiltration strongly correlated with histamine concentration changes, while mast cell infiltration was minimal.
- Histamine-degrading enzyme activity remained unchanged.
- Basophils exhibited piecemeal degranulation in DNCB dermatitis but remained intact in PPD and KLH reactions.
Conclusions:
- The increase in histamine concentration during cutaneous DTH is primarily driven by the infiltration of basophils into lesional sites.
- Mast cells play a minor role in histamine elevation in these DTH models.
- Despite differing activation and degranulation patterns, basophil numbers are the key determinant of histamine levels in DTH.
- Findings highlight the central role of basophils in histamine-mediated DTH responses.