In childhood asthma the degree of allergen-induced T-lymphocyte proliferation is related to serum IgE levels and to blood eosinophilia.
OBJECTIVE
To investigate whether the state of activation of circulating T-cells in childhood asthma could be related to serum IgE levels and/or to blood eosinophilia.


METHODS
Seventeen atopic asthmatic children, sensitized to Dermatophagoides pteronyssinus (Der p), in stable condition at the time of the study and 15 sex-matched and age-matched controls were studied. The expression of activation surface markers (HLA-DR and CD25) on peripheral blood mononuclear cells (PBMCs) was tested by monoclonal antibodies and FACS analysis, while the PBMC proliferative response to Der p antigens was measured by tritiated thymidine (3HTdR) incorporation.


RESULTS
As compared to controls, atopic children showed higher eosinophil counts (P < .01), similar lymphocyte counts (P > .1, each comparison) but higher proportion of HLA-DR+ and CD25+ T-lymphocytes (P < .05, each comparison). A significant Der p allergen-induced PBMC proliferation was observed in atopic children (P < .01) but not in controls (P > .1). Both in controls and in atopic children, no correlations were found between lymphocyte counts and eosinophil counts or total or allergen-specific IgE levels (P > .1, each comparison). In contrast, weak correlations were detected between the degree of allergen-induced PBMC proliferation and: a) allergen-specific IgE levels in serum (P < .05) and b) eosinophil counts (P < .05).


CONCLUSIONS
These data support the concept that the degree of activation of allergen-specific T-lymphocytes in blood may reflect the intensity of allergic sensitization in childhood asthma.
Silvestri
M
M
The Pulmonary Division, G. Gaslini Institute, Genoa, Italy.
Oddera
S
S
Spallarossa
D
D
Frangova Yourukova
V
V
Rossi
G A
GA
D000485:Allergens / Q000276:immunology; D039741:Antigens, Dermatophagoides; D001249:Asthma / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D004802:Eosinophilia; D005260:Female; D006023:Glycoproteins / Q000276:immunology*; D006684:HLA-DR Antigens / Q000378:metabolism; D006801:Humans; D006969:Hypersensitivity, Immediate / Q000276:immunology*; D007073:Immunoglobulin E / Q000097:blood*; D008213:Lymphocyte Activation; D018655:Lymphocyte Count; D008297:Male; D015375:Receptors, Interleukin-2 / Q000378:metabolism; D012882:Skin Tests; D016176:T-Lymphocyte Subsets; D013601:T-Lymphocytes / Q000276:immunology*; D014197:Trees / Q000276:immunology
D000485:Allergens; D039741:Antigens, Dermatophagoides; D006023:Glycoproteins; D006684:HLA-DR Antigens; D015375:Receptors, Interleukin-2; D007073:Immunoglobulin E