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Measuring Local Anaphylaxis in Mice
Published on: October 14, 2014
The effect of VAS972 on allergic contact hypersensitivity
G M Shivji1, H Suzuki, A S Mandel
1Division of Dermatology, Sunnybrook and Women's College Health Science Centre, University of Toronto, Toronto, Ontario, Canada.
Journal of Cutaneous Medicine and Surgery
|September 26, 2000
Summary
VAS972 therapy, which modifies blood with ozone and UVC light, significantly reduces contact hypersensitivity (CHS) responses in mice. Both plasma and cellular components of the treated blood demonstrated immunosuppressive effects, supporting its Th1-downregulating mechanism.
Area of Science:
- Immunology
- Dermatology
- Immunomodulation
Background:
- Contact hypersensitivity (CHS) is a Th1-mediated immune response.
- Immunosuppressive agents and environmental stimuli can down-regulate CHS.
- VAS972 is a novel immunomodulation therapy involving ex vivo blood processing with ozone and UVC light.
Purpose of the Study:
- To evaluate the immune-modulating effect of VAS972 on CHS.
- To assess the efficacy of VAS972 in a CHS animal model.
Main Methods:
- CHS was induced using dinitrofluorobenzene (DNFB) in animal models.
- Animals were treated with VAS972-processed blood, control blood, or saline.
- Preliminary studies investigated the effects of plasma and cellular fractions of processed blood.
Main Results:
- VAS972-processed blood significantly reduced CHS response by 46%.
- Histological analysis showed reduced lymphocytic infiltration in the skin of treated animals.
- Both plasma (49% suppression) and cellular fractions (41% suppression) of VAS972-treated blood induced significant immunosuppression.
Conclusions:
- VAS972 effectively suppresses CHS and associated cellular infiltration.
- The immunosuppressive effects are mediated by both plasma and cellular components of the processed blood.
- These findings support the hypothesis that VAS972 down-regulates the Th1 immune response.
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