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ABSTRACT: Grass pollen immunotherapy for allergic rhinitis is a disease-modifying treatment that results in long-term clinical tolerance lasting years after treatment discontinuation. Active treatment is associated with generation of inhibitory grass pollen-specific IgG antibodies capable of blocking allergen-IgE interactions.
We sought to investigate the involvement of IgG-associated inhibitory antibodies with long-term clinical tolerance after discontinuation of grass pollen immunotherapy.
We conducted a 4-year study in which patients who had moderate-to-severe allergic rhinitis underwent a randomized, double-blind, placebo-controlled discontinuation of subcutaneous grass pollen immunotherapy. All subjects received grass pollen immunotherapy injections for 2 years (n = 13), followed by a further 2 years of either active (n = 7) or placebo (n = 6) injections. Clinical outcomes included seasonal symptoms and use of rescue medication. Serum specimens were collected at baseline and after 2 and 4 years for quantification of allergen-specific IgG antibodies. Sera were also tested for IgG-dependent inhibitory bioactivity against IgE-allergen binding in cellular assays by using flow cytometry and confocal microscopy to detect binding of IgE-grass pollen allergen complexes to B cells.
Clinical improvement was maintained after 2 years of discontinuation. Although immunotherapy-induced grass pollen-specific IgG1 and IgG4 levels decreased to near-preimmunotherapy levels during discontinuation, inhibitory bioactivity of allergen-specific IgG antibodies was maintained unchanged.
Grass pollen immunotherapy induces a subpopulation of allergen-specific IgG antibodies with potent inhibitory activity against IgE that persists after treatment discontinuation and that could account for long-term clinical tolerance.
The Journal of allergy and clinical immunology 02/2011; 127(2):509-516.e1-5. · 9.17 Impact Factor
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ABSTRACT: Regulatory T (Treg) cells play an important role in controlling allergic inflammation. The transcription factor Foxp3 regulates the development and function of natural and adaptive CD4(+)CD25(+) Treg cells.
We sought to examine the effect of grass pollen injection immunotherapy on the numbers of Foxp3(+)CD4(+) and Foxp3(+)CD25(+) T cells in and out of season and their expression of IL-10 in the nasal mucosa of patients with hay fever.
Nasal biopsy specimens were obtained from untreated patients with hay fever, participants with grass pollen allergy who had received 2 years of immunotherapy, and healthy control subjects. Dual-immunofluorescence microscopy was used to enumerate and colocalize Foxp3 expression to CD4(+) and CD25(+) T cells in the nasal mucosa. Triple staining was performed to colocalize Foxp3(+) cells to CD3(+)CD25(+) and CD3(+) IL-10-expressing cells.
At peak season, numbers of Foxp3(+)CD25(+) (P = .02) and Foxp3(+)CD4(+) (P = .03) cells were significantly increased in the nasal mucosa of immunotherapy-treated patients compared with numbers before treatment. Foxp3(+)CD25(+) (P = .03) and Foxp3(+)CD4(+) (P = .04) cells were also greater in immunotherapy-treated patients out of season compared with those in untreated patients with hay fever. Within the immunotherapy-treated group, 20% of CD3(+)CD25(+) cells expressed Foxp3, and 18% of Foxp3(+)CD3(+) cells were IL-10 positive.
The presence of local Foxp3(+)CD25(+)CD3(+) cells in the nasal mucosa, their increased numbers after immunotherapy, and their association with clinical efficacy and suppression of seasonal allergic inflammation support a putative role for Treg cells in the induction of allergen-specific tolerance in human subjects.
The Journal of allergy and clinical immunology 07/2008; 121(6):1467-72, 1472.e1. · 9.17 Impact Factor
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ABSTRACT: Background: Grass pollen immunotherapy is highly effective in reducing seasonal hay fever symptoms and medication requirements. Clinical improvement is accompanied by a reduction in nasal mucosal eosinophils, although the mechanism is unknown.Methods: Nasal biopsies were taken from 37 adults before immunotherapy and during the peak pollen season following 2 years treatment. Biopsies were processed for immunohistochemistry for CCR3, adhesion molecules (intercellular adhesion molecule (ICAM)-1 and vascular cell adhesion molecule (VCAM)-1) and apoptotic cells (terminal deoxyribonucleotidyl transferase-mediated dUTP−digoxigenin nick end-labeling; TUNEL), as well as for interleukin (IL)-4 and IL-13 mRNA-positive cells. Results were compared with eosinophil numbers in the nasal mucosa.Results: Analysis of the clinical data confirmed that the proportion of patients who showed greater than 60% improvement in symptoms (47 and 15%) and in rescue medication (79 and 10%) were significant for the immunotherapy group compared with placebo group (P < 0.03 and P < 0.02, respectively). Seasonal increases were observed for VCAM-1 expression (P = 0.05) and IL-13 mRNA-expressing cells (P < 0.05) in the placebo group, but not in the immunotherapy group. The differences for VCAM-1 expression achieved significance between groups (P = 0.05). There was no significant difference in either ICAM-1 expression or in the number of CCR3+ cells, TUNEL+ apoptotic cells and IL-4 mRNA-expressing cells.Conclusion: Successful grass pollen immunotherapy was associated with inhibition of seasonal increases in nasal eosinophils, IL-13 mRNA-expressing cells and VCAM-1 expression, but no change in CCR3 expression or in the number of apoptotic cells. The reduction in eosinophils after immunotherapy may be due to suppression of eosinophil recruitment to the nasal mucosa rather than enhanced apoptosis.
Allergology International 06/2008; 53(3):255 - 264.
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ABSTRACT: Allergen immunotherapy (IT) has long-term efficacy in IgE-mediated allergic rhinitis and asthma. IT has been shown to modify lymphocyte responses to allergen, inducing IL-10 production and IgG Abs. In contrast, a putative role for IgA and local TGF-beta-producing cells remains to be determined. In 44 patients with seasonal rhinitis/asthma, serum IgA1, IgA2, and polymeric (J chain-containing) Abs to the major allergen Phl p 5 were determined by ELISA before and after a 2-year double-blind trial of grass pollen (Phleum pratense) injection IT. Nasal TGF-beta expression was assessed by in situ hybridization. Sera from five IT patients were fractionated for functional analysis of the effects of IgA and IgG Abs on IL-10 production by blood monocytes and allergen-IgE binding to B cells. Serum Phl p 5-specific IgA2 Abs increased after a 2-year treatment (approximately 8-fold increase, p = 0.002) in contrast to IgA1. Increases in polymeric Abs to Phl p 5 (approximately 2-fold increase, p = 0.02) and in nasal TGF-beta mRNA (p = 0.05) were also observed, and TGF-beta mRNA correlated with serum Phl p 5 IgA2 (r = 0.61, p = 0.009). Post-IT IgA fractions triggered IL-10 secretion by monocytes while not inhibiting allergen-IgE binding to B cells as observed with IgG fractions. This study shows for the first time that the IgA response to IT is selective for IgA2, correlates with increased local TGF-beta expression, and induces monocyte IL-10 expression, suggesting that IgA Abs could thereby contribute to the tolerance developed in IT-treated allergic patients.
The Journal of Immunology 05/2007; 178(7):4658-66. · 5.79 Impact Factor
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ABSTRACT: Exposure to diisocyanates in the workplace is an important cause of occupational asthma. The majority of patients with diisocyanate-induced asthma have no detectable diisocyanate-specific IgE antibodies in serum. There has been much debate as to whether this is due to diisocyanate-induced asthma being mediated by non-IgE mechanisms or whether it is the result of using inappropriate conjugates.
We sought to determine whether RNA message for Cepsilon, IL-4, and other associated inflammatory markers could be detected locally within the bronchial mucosa after diisocyanate challenge.
Fiberoptic bronchoscopic bronchial biopsy specimens were obtained at 24 hours after both a control and an active challenge in 5 patients with positive and 7 patients with negative inhalation test responses to diisocyanates. Using both immunohistochemistry and in situ hybridization, we determined mRNA for Cepsilon, IL-4, IL-5, and other associated inflammatory markers.
There was a striking absence of Cepsilon and IL-4 mRNA-positive cells in bronchial biopsy specimens from patients challenged with diisocyanate (Cepsilon median of 0 and interquartile range of 0-1.85; IL-4 median of 0 and interquartile range of 0-0.85). In contrast, there were increased numbers of IL-5-, CD25-, and CD4-positive cells and a trend toward an increase in eosinophils after active challenge with diisocyanate.
We found a striking absence of both bronchial Cepsilon and IL-4 RNA message after inhalation challenge with diisocyanates, irrespective of whether the challenge test response was positive or negative. We propose that diisocyanate-induced asthma is a non-IgE-mediated disease, at least in patients in whom specific IgE antibodies to diisocyanates are undetectable.
Journal of Allergy and Clinical Immunology 04/2006; 117(3):663-9. · 11.00 Impact Factor
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ABSTRACT: Background IL-9 is an important stimulus for tissue infiltration by mast cells, a feature requiring concomitant activation of c-Kit. Objectives We assessed IL-9 expression and c-Kit + mast cells in the nasal mucosa of patients with allergic rhinitis during seasonal pollen exposure and observed the effects of allergen immunotherapy. Methods We studied 44 patients with seasonal rhinitis and asthma before and 2 years after a double-blind trial of grass pollen immunotherapy. Nasal mucosal IL-9 + cells and c-Kit + mast cells were assessed by means of immunochemistry. Cell types expressing IL-9 protein were determined by means of dual immunofluorescence. IL-9 mRNA-positive cells were assessed by means of in situ hybridization, and their phenotype was determined by using sequential immunohistochemistry and in situ hybridization. Results Nasal mucosal c-Kit + mast cells were increased during the pollen season ( P = .0001). IL-9 mRNA-positive cells also tended to increase ( P = .1) and correlated with nasal EG2 + eosinophils ( r = 0.47, P = .05) and IL-5 mRNA-positive cells ( r = 0.54, P = .02). The cell sources of IL-9 included T cells, eosinophils, neutrophils, and mast cells. When compared with placebo, successful pollen immunotherapy markedly inhibited seasonal increases in nasal mucosal c-Kit + mast cells ( P = .001) and the seasonal expression of IL-9 mRNA-positive cells ( P = .06). Immunotherapy also inhibited IL-9 protein expression from nonendothelial cell sources ( P = .0007). Conclusion IL-9 is upregulated in the nasal mucosa during the pollen season and correlates with tissue infiltration by eosinophils. Successful pollen immunotherapy is associated with inhibition of seasonal increases in both nasal c-Kit + mast cells and eosinophils. This effect might be explained, at least in part, by the reduced local expression of IL-9.
Journal of Allergy and Clinical Immunology 08/2005; 116(1):73-9. · 11.00 Impact Factor
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ABSTRACT: Allergic rhinitis is an inflammatory nasal disorder in which a range of different cells participates. A variety of approaches has been used to monitor nasal inflammation objectively to investigate disease processes and to evaluate the effect of therapeutic intervention. These approaches include nasal lavage, nasal cytology, and nasal biopsy, together with the more recently established measurement of nasal nitric oxide (NO) concentration. Although all provide information about nasal mucosal inflammation, the extent of information that can be obtained by each approach, the ease of sampling, and the complexity of sample handling differ. Such considerations influence the choice of approach when measurement of nasal inflammation is to be an objective outcome parameter in a clinical trial. In addition, the choice of approach is also determined by the questions or hypotheses that are to be addressed. Nasal lavage is simple and rapid to perform, is well tolerated, and provides a sample that can provide information about luminal cell recruitment, cell activation, and plasma protein extravasation. Nasal cytology involves sampling and recovering mucosal surface cells. It is also easy to perform and is well tolerated in general, although some find that the procedure causes a transient unpleasant sensation. A differential cell count from the sample provides information about relative cell populations. Both nasal lavage and nasal cytology are readily applicable to clinical trials. Nasal cytology sample handling is easier, but nasal lavage offers the advantage of providing considerably greater information from the sample. Nasal biopsy is a considerably more invasive procedure and requires expertise not only in tissue sampling but also in biopsy processing. Therefore, it is applicable only in specialist centers. However, nasal biopsy is the only sampling technique that directly informs about tissue cellular events, although these may be implied, in part from the other sampling approaches. Tissue specimens can be used to evaluate both protein and gene expression. Measurement of nasal NO involves expensive equipment but provides an instantaneous result, unlike the other approaches, all of which require sample processing and analysis. Recommendations for standardization of measurement have been made, and measures are considered in part to reflect allergic inflammation within the nasal mucosa. The limitations of nasal NO are that it reflects only a certain aspect of allergic mucosal inflammation, and that because a proportion of nasally measured NO is derived from the sinuses under normal circumstances, nasal NO is not specific for nasal disease. The high contribution from the sinus mucosa limits the discriminatory ability of nasal NO to reflect nasal tissue-specific alterations. The incorporation of measures of nasal inflammation in clinical trials has distinguished anti-inflammatory therapy from symptomatic therapy and has the potential to provide information about the efficacy of novel therapies for allergic rhinitis.
The Journal of allergy and clinical immunology 04/2005; 115(3 Suppl 1):S414-41. · 9.17 Impact Factor
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ABSTRACT: T regulatory cells and IL-10 have been implicated in the mechanism of immunotherapy in patients with systemic anaphylaxis following bee stings. We studied the role of IL-10 in the induction of clinical, cellular, and humoral tolerance during immunotherapy for local mucosal allergy in subjects with seasonal pollinosis. Local and systemic IL-10 responses and serum Ab concentrations were measured before/after a double-blind trial of grass pollen (Phleum pratense, Phl P) immunotherapy. We observed local increases in IL-10 mRNA-positive cells in the nasal mucosa after 2 years of immunotherapy, but only during the pollen season. IL-10 protein-positive cells were also increased and correlated with IL-10 mRNA(+) cells. These changes were not observed in placebo-treated subjects or in healthy controls. Fifteen and 35% of IL-10 mRNA signals were colocalized to CD3(+) T cells and CD68(+) macrophages, respectively, whereas only 1-2% of total CD3(+) cells and 4% of macrophages expressed IL-10. Following immunotherapy, peripheral T cells cultured in the presence of grass pollen extract also produced IL-10. Immunotherapy resulted in blunting of seasonal increases in serum allergen Phl p 5-specific IgE, 60- to 80-fold increases in Phl p 5-specific IgG, and 100-fold increases in Phl p 5-specific IgG4. Post-immunotherapy serum exhibited inhibitory activity, which coeluted with IgG4, and blocked IgE-facilitated binding of allergen-IgE complexes to B cells. Both the increases in IgG and the IgG "blocking" activity correlated with the patients' overall assessment of improvement. Thus, grass pollen immunotherapy may induce allergen-specific, IL-10-dependent "protective" IgG4 responses.
The Journal of Immunology 04/2004; 172(5):3252-9. · 5.79 Impact Factor
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ABSTRACT: Chemokine receptors play an important role in the migration of leukocytes to sites of allergic inflammation in humans. In this study, we have identified increased expression of the chemokine receptor CXCR1 on CD4+ T lymphocytes derived from patients with atopic disease compared with normal donors. Enhanced expression of CXCR1 by atopic donors was identified on freshly isolated peripheral blood cells and on expanded cell populations derived from nasal mucosal biopsies and from the periphery. Identification of CXCR1 expression on CD4 cells in the nasal mucosa was confirmed by double immunofluorescence. In addition, expression of CXCR1 was dramatically decreased in patients undergoing successful treatment of allergic rhinitis by specific immunotherapy. CXCR1 provided a functional receptor capable of regulating T cells in the context of allergic disease, since expression of CXC chemokine ligand 8 was up-regulated at the site of allergic inflammation and freshly isolated CXCR1+CD4+ cells from atopic donors showed an enhanced functional response to this ligand. CXCR1 expression on CD4+ T cells was increased in vitro in response to the pro-Th2 cytokine IL-4. Phenotypic analysis reveals that IFN-gamma expression was lower in the CXCR1+CD4+ cells. The identification of CXCR1 as a marker of allergic rhinitis reveals a possible target for therapeutic intervention in atopic disease.
The Journal of Immunology 02/2004; 172(1):268-73. · 5.79 Impact Factor
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Kayhan T Nouri-Aria,
Duncan Wilson,
James N Francis,
Louise A Jopling, Mikila R Jacobson,
Martin R Hodge,
David P Andrew,
Stephen J Till,
Eva-Maria Varga,
Timothy J Williams,
James E Pease,
Clare M Lloyd,
Ian Sabroe,
Stephen R Durham
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ABSTRACT: We studied the regulation of CCR4 expression in peripheral blood and in human models of cutaneous and pulmonary allergen challenge. CCR4 expression was detectable on freshly isolated CD4+ lymphocytes and in CD4+ and CD8+ T cell lines derived from blood of atopic donors. Numbers of CCR4+ cells were up-regulated in T cell lines expanded in the presence of IL-4. CCR4 mRNA was absent at baseline in normal subjects in lung and skin, but present at baseline in the lung of some atopics. Baseline expression of CCR4 mRNA and protein was higher in lung vs. skin, but allergen-induced increases in CCR4 mRNA+ cells were observed in both organs. CCR4 protein+ cells were present at higher levels after allergen challenge in atopics compared to normal subjects. CCR4 may be important in the recruitment of T lymphocytes at sites of allergic inflammation, in a non-organ-specific manner.
European Journal of Immunology 08/2002; 32(7):1933-8. · 5.10 Impact Factor
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Kayhan T. Nouri-Aria,
Duncan Wilson,
James N. Francis,
Louise A. Jopling, Mikila R. Jacobson,
Martin R. Hodge,
David P. Andrew,
Stephen J. Till,
Eva-Maria Varga,
Timothy J. Williams,
James E. Pease,
Clare M. Lloyd,
Ian Sabroe,
Stephen R. Durham
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ABSTRACT: We studied the regulation of CCR4 expression in peripheral blood and in human models of cutaneous and pulmonary allergen challenge. CCR4 expression was detectable on freshly isolated CD4+ lymphocytes and in CD4+ and CD8+ T cell lines derived from blood of atopic donors. Numbers of CCR4+ cells were up-regulated in T cell lines expanded in the presence of IL-4. CCR4 mRNA was absent at baseline in normal subjects in lung and skin, but present at baseline in the lung of some atopics. Baseline expression of CCR4 mRNA and protein was higher in lung vs. skin, but allergen-induced increases in CCR4 mRNA+ cells were observed in both organs. CCR4 protein+ cells were present at higher levels after allergen challenge in atopics compared to normal subjects. CCR4 may be important in the recruitment of T lymphocytes at sites of allergic inflammation, in a non-organ-specific manner.
European Journal of Immunology 06/2002; 32(7):1933 - 1938. · 5.10 Impact Factor
