Serum IFN-* and IL-10 levels before and after specific immunotherapy in patients with allergic rhinitis
G. Keskin*, A. Inal**, R. Ali Sari***, A. Sengül**, M. Sahin***, M. Turgay*** and G. Kinikli***
*SSKAnkara Ihtisas Hospital Clinic Immunology and Rheumatology Department. **Gülhane Military Medical Academy. Department of Immunology. Ankara. ***Medical Faculty of Ankara University. Department of Immunology. Ankara. Türkiye.
Correspondence:
Kibris sokak, 25/3 A.Ayranci-06690
Ankara-TÜRK.IYE
SUMMARY
Althoug a detailed explanation of the mechanism of immunotherapy is not known, several immunologic explanation have been proposed. It''s said that T cell-cytokine profile changed with allergen immunotherapy. In our study we evaluated IFN-* and IL-10 levels before and after immunotherapy in patients with allergic rhinitis. Twenty patients (mean age; 27.3 ± 4.84), 8 male, 12 female with allergic rhinitis, mean duration of disease was 5.55 ± 1.23 years and 13 healthy controls, 5 male, 8 female (mean age: 28.38 ± 5.61) were enrolled in the study. Immunotherapy was performed for grass pollen allergen extract to patients with allergic rhinitis for 31.5 ± 4.98 months. Serum IL-10 and IFN-* levels were evaluated with ELISA. Serum IL-10 levels were significantly high before and after immunotherapy compared to controls. There was no difference in IFN-* levels before and after SIT compared to controls.
According to this study, in patients with allergic rhinitis after immunotherapy serum IL-10 levels are decreased but IFN-* no change.
Key words: Allergic rhinitis. Immunotherapy. IL-10. IFN-*.
RESUMEN
Aunque no se conoce una explicación detallada del mecanismo de la inmunoterapia, se han propuesto varias explicaciones inmunológicas. Se cree que el perfil de citocinas de las células T cambia tras la inmunoterapia con alergeno. En nuestro estudio evaluamos los niveles de IFN-* y de IL-10 antes y después de la inmunoterapia en pacientes con rinitis alérgica. Se incluyeron en el estudio 20 pacientes (edad media; 27,3 ± 4,84), ocho varones y 12 mujeres, con rinitis alérgica y una duración media de la enfermedad de 5,55 ± 1,23 años y 13 controles sanos, cinco varones y ocho mujeres (edad media; 28,38 ± 5,61). La inmunoterapia se realizó mediante la administración de extracto de alergeno de polen de hierba a pacientes con rinitis alérgica durante 31,5 ± 4,98 meses. Los niveles de IL-10 y de IFN-* se evaluaron mediante ELISA. Los niveles séricos de IL-10 fueron significativamente mayores antes y después de la inmunoterapia, en comparación con los controles. No hubo diferencia en cuanto a los niveles de IFN-* antes y después de la SIT en comparación con los controles.
Según este estudio, los niveles séricos de IL-10 disminuyeron después de la inmunoterapia en pacientes con rinitis alérgica, pero el IFN-*no cambió.
Palabras clave: Rinitis alérgica. Inmunoterapia. IL-10. IFN-*.
INTRODUCTION
Specific immunotherapy (SIT) of allergic disease generally consists of regular injections of progressively increasing doses of relevant allergens to sensitive patients. Immunotherapy was highly succesfull in reduction clinical symptoms an requirements of topical and oral medications. Although a detailed explanation of the mechanism of (SIT) is not known, several immunologic explanation have been proposed (1). There are many steps in the pathway from T cell sensitization to allergic inflammation where immunotherapy might potentially act. Conventional allergen immunotherapy effectively ameliorates allergic rhinitis by increasing the development of allergic-specific Th1 cells and decreasing the development of Th2 cells (2). Th2 cells are important in humoral immunity and allergic disease. CD4+ T cell heterogeneity explains the development of allergic disease as the result of an over production of Th2 cytokine (3). In this study; we evaluated serum levels of Th1 cytokine IFN-* and Th2 cytokine IL-10 before and after immunotherapy in patients with allergic rhinitis.
MATERIALS AND METHOD
Twenty patients (8 male, 12 female) with allergic rhinitis who have sensitivity to grass pollen allergens and participated to immunotherapy programme and 5 male, 8 female, 13 (mean age: 28.38 ± 5.61) healthy controls (all had no history of allergic disorders) were enrolled the study. All the patients had histories of seasonal allergic symptoms and positive cutaneous prick tests (weal diameter > 5 mm) towards grass pollen extract. The mean age of the patients was 27.3 ± 4.84 and mean duration of the disease was 5.55 ± 1.23 years. Immunotherapy was performed using a single batch of aluminium adsorbed depot grass pollen extracts. All of the patients were performed SIT with grass pollen extract. Injections were administered twice weekly up to a maintenance volume of 1 ml. Thereafter injections were administered monthly. Daily symptom scores were recorded on diary cards according to SIT protocol from march through spetember. The size of the skin responses after skin prick tests were recorded before and after SIT. Mean duration of SIT to allergens was 31.5 ± 4.98 months. All patients, skin prick tests were performed with standardized soluprick SQ, ALK, Horsholm, Denmark. Serum total IgE levels were evaluated before and after SIT.
Serum samples were collected from the patients who had not received any medication in previous 1 month period. Serum samples from the patients and controls were stored at 70° C in deep freeze until the study. Total serum IgE and specific IgE antibody (AlaSTAT, Behring Diagnostici Ruel-malmaison, France) were measured before and after immunotherapy. IFN-* (Cytoscreen, Biosource International, USA) and IL-10 (Cytoscreen, Biosource International, USA) levels were evaluated by ELISA before and after SIT in the patients and controls.
Statistical analysis was made by paired t test and Wilcoxon test.
RESULTS
Clinical results have been reported previously (4). The severity of symptom scores was assessed on a scale of 0-3. When after SIT period was compared with before SIT period, there were significant reductions in mean monthly symptom scores (before SIT 44.14 ± 29.12, after SIT 13.14 ± 7.1) (p < 0.01). Mean monthly symptom scores are shown figure 1. Mean IgE levels was 352.5 ± 65.3 in patients before SIT, 102.8 ± 54.7 after SIT and 35.4 ± 15.7 in controls. Before SIT, mean IgE level was significantly high compared with after SIT and the healthy controls (p < 0.01). The size of the immediate response after intradermal injection of 10 SQ-U allegen extract were recorded before and after SIT. According to this, after SIT period, the size of the immediate response showed a statistically significant decrease compared with before SIT (p < 0.01).
In the patient group serum IL-10 levels were 64.99 ± 17.39 pg/ml before SIT and 31.55 ± 7.21 pg/ml after SIT. IFN-* levels 23.66 ± 5.31 pg/ml before SIT, 25.14 ± 9.68 pg/ml after SIT. In the control group, the mean serum IL-10 level was 28.35 ± 5.33 pg/ml and mean serum IFN-* level was 20.18 ± 8.17 pg/ml (Figs. 2 and 3).
According to these results; IL-10 levels before SIT was significantly high compared to control and after SIT (p < 0.001). In contrast there was no difference in serum IFN-* levels in the patient group before and after SIT and compared to controls (p > 0.05).
DISCUSSION
Over production of Th2 cytokines in patients with allergy causes allergic disease. The outcome of immunotherapy is reversal of the dominant allergen-specific Th phenotype in clinically improved patients, as a result of the conversion of Th2 cells into Th1 cells or the selective expansion of antigen-specific Th1 cells (5). So the serum levels of the cytokines production from those cells are also change. Recently, attention has been directed to immunoregulatory mechanisms and changes in the cytokine profile of allergen reactive T cells. IL-10 is produced by Th2 cells, mast cells, monocytes, B lymphocytes, eosinophils, keratinocytes (6). IL-10 acts to inhibit to proinflammatory cytokines, growth factor and chemokine production by mononuclear phagocytes (6). It downregulates various inflammatory events. One of them is allergic inflammation. The role of IL-10 in allergic inflammation is still not fully understood. Monocytes pretreated with IL-10 fail to induce antigen-specific T-cell proliferation (7). IL-10 inhibits proliferation of T cells activated by anti CD3 antibodies in the absence of antigen-presenting cell. Although some studies have demonstrated IL-10 production by human Th2 lymphocytes, it has also been shown that IL-10 is a product of human Th1 cells (8). So there are many confliting results in literature.
In our study, serum IL-10 levels significantly high in before SIT compared with after SIT. This result is similar with literature. Serum IL-10 levels after SIT is similar with controls. In two studies have demonstrated that immunotherapy is associated with significantly enhanced IL-10 production (9, 10).
IL-10 has been reported to inhibit the synthesis of many cytokines such as TNF alpha, IL-1 and IFN-*, allergic inflammation, antigen-specific T cell proliferation and induce T cell anergy (11, 12). It is not known by which mechanism IL-10 inhibits IFN-*. Allergic disease is thought to be caused by the disregulation of cytokine synthesis and the inapropriate production by alergen-specific CD+ T cells of IL-4 and IL-10 but not IFN-* (13, 14). Th1 cells are assumed to protect against the development of allergic symptoms, particularly because IFN-* has inhibitory effects on IgE synthesis and because allergen specific Th1 cells can be found in non allergic individuals (15). Secrist et al (2) reported a decrease in allergen-induced IL-4 production following SIT, but no alteration in IFN-* production by CD8 depleted PBMC. In contrast O''Brien et al (16) showed a highly significant reduction in the production of IFN-* before and afer SIT.
In a study it was reported that grass pollen immunotherapy indicated IFN-* mRNA expression but did not changed IL-4 and IL-5 mRNA (17). In other study venom immunotherapy induced an altered cytokine mRNA patterns in allergen-stimulated T cells which was dissociated from the early changes of allergen-induced T cell responsivenes (18). In an another study decreased IL-10 and IFN-* mRNA expression were found after immunotherapy in patients with allergic rhinitis (19). In our study IFN-* levels did not change before and after SIT too.
According to this study, in patients with allergic rhinitis after SIT serum IL-10 levels are decreased but IFN-* no change.
REFERENCES
1. Rocklin RE. Clinical and immunological aspects of allergen-specific immunotherapy in patients with seasonal allergic rhinitis and/or asthma. J Allergy Clin Immunol 1983;72: 323-8.
2. Secrist H, Chelen CJ, Wen Y, et al. Allergen immunotherapy decreases interlukin 4 production in CD4+ T cells from allergic individuals. J Exp Med 1993;178:2123-30.
3. Nakagawa T, Gershwin ME. Immunotherapy of allergic diseases. Int Arch Allergy Immunol 1993;1021:117-32.
4. Varney VA, Gaga M, Frew AJ, et al. Usefulness of immunotherapy in patients with severe summer hay fever uncontrolled by antiallergic drugs. BMJ 1991;302:265-9.
5. Kapsenberg ML, Hilkens CMU, Boa JD, et al. Production and modulation of T cell cytokines in atopic allergy. Int Arch Allergy Immunol 1996;110:107-13.
6. Larry Borish. IL-10: evolving concepts. J Allergy Clin Immunol 1998;101:293-7.
7. Ding L, Linsley PS, Huang LY, et al. IL-10 inhibits macrophage costimulatory activity by selectively inhibiting the up regulation of B7 expression. J Immunol 1993;151:1224-34.
8. Ysel H, De Waal Malefyt R, Roncarolo MG, et al. IL-10 is produced by subsets of human CD4+ T cell clones and peripheral blood T cells. J Immunol 1992;149:2378-84.
9. Bellinghausen I, Metz G, Enk AH, et al. Insect venom immunotherapy induces IL-10 production a Th2 to Th1 shift, and changes surface marker expression in venom-allergic subjects. Eur J Immunol 1997;27:1131-9.
10. Gaglani B, Borish L, Bartelson BLB, et al. Local nasal immunotherapy is effective in treating weed-induced allergic rhinitis. Ann Allergy Asthma Immunol 1997;79:259-65.
11. Fiorentino DF, Bond WF, Mosmann TR. Two types of mouse T helper cell. Th2 clones secrete a factor that inhibits cytokine production by Th1 clones. J Exp Med 1989;170:2081-95.
12. Editorial. Immunotherapy-anergy, deviation or suppression? Clin Exp Allergy 1998;28:911-6.
13. Wierenga EA, Snock C, De Groot I, et al. Evidence for compartmentalization of functional subsets of CD4+ T lymphocytes in atopic patients. J Immunol 1990;144:4651-5.
14. Kapsenberg ML, Wierenga EA, Bos JD et al. Functional subsets of allergen-reactive human CD4+ T cells. Immunol Today 1991;12:392-7.
15. Umetsu TD, DeKruyff RH. Th1 and Th2 CD4+ cells in human allergic disease. J Allergy Clin Immunol 1997;100:1-6.
16. O''Brien RM, Byron KA, Varigos GA, Thomas WR. House dust mite immunotherapy results in a decrease in Der p 2-specific IFN-* and IL-4 expression by circulating T lymphocytes. Clin Exp Allergy 1997;27:46-51.
17. Varney VA, Hamid QA, Gaga M, et al. Influence of grass pollen immunotherapy on cellular infiltration and cytokine mRNA expression during allergen-induced late-phase cutaneous responses. J Clin Invest 1993;92:644-9.
18. Akoum H, Tsicopoulos A, Vorng H, et al. Venom immunotherapy modulates interleukin 4 and interferon-* messenger RNA expression of peripheral T lymphocytes. Immunology 1996; 87:593-8.
19. Ankie S, Gabrielsson S, Paulie S, et al. Allergen induced cytokine profiles in type I allergic individuals before and after immunotherapy. Immunol Lett 1997;57:177-81.
