Allergen-induced accumulation of eosinophils and lymphocytes in skin chambers is associated with increased levels of interleukin-4 and sVCAM-1.
BACKGROUND
The aim of the study was to characterize the kinetic accumulation of various inflammatory mediators in allergen-challenged skin chambers applied on patients with pollen-related allergic rhinitis/mild asthma.


METHODS
Skin blisters were induced on the forearms and challenged with allergen or phosphate-buffered saline (PBS). Peripheral blood was drawn before and 8 h after challenge for analysis of differential cell counts, sVCAM-1, and alpha2-macroglobulin. Chamber fluids, collected at 1, 4, and 8 h after allergen application, were analyzed for differential cell counts, histamine, interleukin (IL)-4, sVCAM-1, and alpha2-macroglobulin.


RESULTS
The number of recruited leukocytes was equal in allergen and PBS chambers; however, the numbers of eosinophils and lymphocytes were significantly (P< or =0.05) elevated in allergen-challenged chambers at 8 h. Compared to PBS chambers, allergen chambers contained significantly (P<0.01-0.05) higher levels of histamine (at 1 and 4 h), IL-4 (at 4 and 8 h), alpha2-macroglobulin (at 1 and 8 h), and sVCAM-1 (at 1 and 8 h). In contrast to alpha2-macroglobulin, levels of sVCAM-1 in peripheral blood were significantly (P<0.05) increased at 8 h.


CONCLUSIONS
Increased levels of sVCAM-1 and IL-4 in allergen-challenged chambers, in parallel with increased recruitment of eosinophils and lymphocytes, points to the participation of IL-4 and VCAM-1 in the development of the late-phase reaction. Increased levels of sVCAM-1 in allergen-challenged chambers probably reflects a combination of leakage and local production.
Fernvik
E
E
Department of Laboratory Medicine, Karolinska Hospital and Institute, Stockholm, Sweden.
Halldén
G
G
Lundahl
J
J
Raud
J
J
Alkner
U
U
van Hage-Hamsten
M
M
Grönneberg
R
R
D000328:Adult; D000485:Allergens / Q000008:administration & dosage / Q000276:immunology*; D001249:Asthma / Q000276:immunology; D001768:Blister / Q000276:immunology; D004804:Eosinophils / Q000276:immunology*; D005260:Female; D005434:Flow Cytometry; D006632:Histamine / Q000378:metabolism; D006801:Humans; D018836:Inflammation Mediators / Q000032:analysis*; D015847:Interleukin-4 / Q000378:metabolism*; D007958:Leukocyte Count; D008214:Lymphocytes / Q000276:immunology*; D008297:Male; D011058:Pollen / Q000276:immunology*; D011852:Radioallergosorbent Test; D006255:Rhinitis, Allergic, Seasonal / Q000209:etiology / Q000276:immunology*; D012882:Skin Tests; D019010:Vascular Cell Adhesion Molecule-1 / Q000378:metabolism*; D000511:alpha-Macroglobulins / Q000378:metabolism
D000485:Allergens; D018836:Inflammation Mediators; D019010:Vascular Cell Adhesion Molecule-1; D000511:alpha-Macroglobulins; D015847:Interleukin-4; D006632:Histamine