T-cell cytokine pattern at three time points during specific immunotherapy for mite-sensitive asthma.
BACKGROUND
Several lines of evidence indicate that specific immunotherapy may act by modifying the patterns of cytokines produced by helper T cells. However, different protocols have been used and different results obtained.


OBJECTIVE
To quantify the effect of specific immunotherapy on the TH1/TH2 T-cell cytokine pattern at the single cell level.


METHODS
We examined the interferon-gamma/interleukin-4 ratio in peripheral blood CD4+ and CD8+ T cells from 12 subjects with house dust mite-sensitive asthma using a flow cytometric method of intracellular cytokine detection. Cytokine production was determined following stimulation with phorbol myristate acetate/ionomycin, a policlonal activator. Subjects were examined at three occasions: before specific immunotherapy, after the 3-months dose increase phase and after 1 year of treatment. During the treatment year patients kept a diary in which they recorded: (a) symptoms of asthma according to a 0-3 grading (0 = absent, 1 = mild, 2 = moderate, 3 = severe); (b) number of puffs (100 microg) per day of salbutamol required to control symptoms; and (c) peak expiratory flow.


RESULTS
Specific immunotherapy improved clinical indices of disease activity including symptom scores and medication use during the treatment year, and had a marked effect in increasing the interferon-gamma/interleukin-4 ratio in peripheral blood CD4+ T cells already after the dose increase phase (5.47 +/- 1.5 vs 4.07 +/- 1.49%, P = 0.03) with and a further rise after 1 year's treatment (16.12 +/- 2.8 vs 4.07 +/- 1.49 and 16.12 +/- 2.8 vs 5.47 +/- 1.5%, P = 0.001 and P = 0.002, respectively). There were no significant changes in the interferon-gamma/interleukin-4 ratio in peripheral blood CD8+ T cells at the three times of the study.


CONCLUSIONS
These data add to view that the efficacy of specific immunotherapy may be attributed to a modified cytokine secretion of CD4+ T cells.
Majori
M
M
Istituto di Clinica delle Malattie dell'Apparato Respiratorio dell'Università degli Studi; Centro di Allergologia e Immunologia Clinica dell'Azienda Unità Sanitaria Locale, Parma, Italy.
Caminati
A
A
Corradi
M
M
Brianti
E
E
Scarpa
S
S
Pesci
A
A
D000328:Adult; D000485:Allergens / Q000276:immunology; D000818:Animals; D039741:Antigens, Dermatophagoides; D001249:Asthma / Q000276:immunology / Q000628:therapy*; D015496:CD4-Positive T-Lymphocytes / Q000276:immunology; D016207:Cytokines / Q000096:biosynthesis*; D003888:Desensitization, Immunologic; D005260:Female; D005434:Flow Cytometry; D006023:Glycoproteins / Q000276:immunology; D006801:Humans; D007371:Interferon-gamma / Q000096:biosynthesis; D015847:Interleukin-4 / Q000096:biosynthesis; D008297:Male; D008925:Mites / Q000276:immunology*; D018417:Th1 Cells / Q000276:immunology*; D018418:Th2 Cells / Q000276:immunology*
D000485:Allergens; D039741:Antigens, Dermatophagoides; D016207:Cytokines; D006023:Glycoproteins; D015847:Interleukin-4; D007371:Interferon-gamma