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PubMed2000

The molecular role of mast cells in atherosclerotic cardiovascular disease.

Human atherosclerosis has many characteristics of an inflammatory disorder. Recent data suggest that mast cells might be important in the pathogenesis of atherosclerotic disease. By secretion of pro-inflammatory cytokines, mast cells can assist in the recruitment of monocytes and lymphocytes into vascular tissue, thereby propagating the inflammatory response. Mast cell enzymes might activate pro-metalloproteinases, thereby destabilizing atheromatous plaques. Mast cells can facilitate foam cell formation by promoting cholesterol accumulation. However, mast cell tryptase could slow thrombus formation at sites of plaque rupture by interfering with coagulation. Therefore, mast cells can modulate coronary artery disease by both facilitatory and inhibitory pathways.

Arteriosclerosis↗
PubMed2001

Proteinase inhibitors from the medicinal leech Hirudo medicinalis.

The medicinal leech Hirudo medicinalis produces various types of proteinase inhibitors: bdellins (inhibitors of trypsin, plasmin, and acrosin), hirustasin (inhibitor of tissue kallikrein, trypsin, alpha-chymotrypsin, and granulocyte cathepsin G), tryptase inhibitor, eglins (inhibitors of alpha-chymotrypsin, subtilisin, and chymasin and the granulocyte proteinases elastase and cathepsin G), inhibitor of factor Xa, hirudin (thrombin inhibitor), inhibitor of carboxypeptidase, and inhibitor of complement component C1s. This review summarizes data on their primary and tertiary structures, action mechanisms, and biological activities.

Animals↗
PubMed2003

Allergen-induced mediator release tests.

The diagnosis of allergic reactions in clinical practice is based on both clinical history and the determination of specific immunoglobulin E (IgE), either in the serum or on skin mast cells. However, for various reasons, identification of the causative factors is not possible in all the cases. Moreover, not all allergies are IgE-dependent. In an attempt to find sensitive, specific and cost-effective methods to investigate hypersensitivity reactions, in vitro tests were developed at a very early stage. Allergen-induced mediator release assays analyze the mediator released from effector cells, mainly peripheral blood cells, when stimulated in vitro with serial dilutions of the putative allergens. Described initially as research tools, they could well become diagnostic tests. However, relatively few high quality reports have been published so far. In this review, we will detail allergen-dependent histamine, tryptase, arachidonic acid metabolite, e.g. cysteinyl leukotrienes and 15-hydroxyeicosatetraenoic mediator release tests.

Allergens↗
PubMed1999

Inflammatory cell populations and cytokine mRNA expression in the nasal mucosa in aspirin-sensitive rhinitis.

Aspirin-sensitive rhinitis is characterized by severe perennial nasal congestion and discharge. The study questioned whether this disease, like immunoglobulin E-mediated rhinitis, might be associated with local recruitment and activation of T-lymphocytes, mast cells and eosinophils with parallel increases in "T-helper2-type" cytokines. Nasal biopsies from 10 patients with aspirin-sensitive rhinitis and 12 healthy controls subjects were studied. Nasal mucosal sections were examined by immunohistochemistry in order to determine cell phenotypes and by in situ hybridization to detect cells expressing messenger ribonucleic acid (mRNA) for cytokines. In aspirin-sensitive rhinitis there were increases in total (CD3+) (p=0.05) and activated (CD25+) T-cells (p=0.007), total (major basic protein (MBP) positive) (p=0.004) and activated (monoclonal antibody which recognizes the cleaved form of eosinophil cationic protein (EG2) positive) eosinophils (p=0.003), tryptase+ mast cells (p=0.04) and CD68+ macrophages (p=0.002). Neutrophils and cells expressing human leukocyte antigen-DR were no different. Marked increases were observed in the numbers of interleukin (IL)-5 mRNA+ cells (p=0.004) in aspirin-sensitive patients, whereas lower numbers of IL-4 mRNA+ cells were observed, with a trend for a difference from controls (p=0.07). No differences were observed for either IL-2 or interferon-gamma. In conclusion, in aspirin-sensitive rhinitis there is intense inflammation of the nasal mucosa characterised by T-lymphocytes, eosinophils and mast cells. The predominance of macrophages and disproportionate increase in interleukin-5 compared to interleukin-4 messenger ribonucleic acid expression suggests that factors other than "allergic" mechanisms may be important in this disease.

Adult↗
PubMed2000

Mast cells correlate with angiogenesis and poor outcome in stage I lung adenocarcinoma.

Angiogenesis is in part related to mast cells. However, the biological significance of mast cells within lung carcinoma remains unclear. Immunohistochemistry was used to stain for tryptase, CD34 and vascular endothelial growth factor (VEGF) in 85 cases of stage I nonsmall cell lung carcinoma. VEGF was found in 33 of 53 adenocarcinomas and 14 of 32 squamous cell carcinomas. Cases of adenocarcinoma had significantly higher mast cell counts than those of squamous cell carcinoma. In adenocarcinoma, mast cell counts in VEGF-positive tumours were significantly higher than in VEGF-negative tumours, whereas in squamous cell carcinoma they were not. Good correlation was observed between intratumoural mast cell counts and microvessel counts. Double staining showed most intratumoural mast cells expressed VEGF. Importantly, only in lung adenocarcinoma, members in the high mast cell count group had significantly worse prognosis than those in the low mast cell count group. It is concluded that tumour-released vascular endothelial growth factors may be related to mast cell accumulation, intratumoural mast cells may produce vascular endothelial growth factor, and stromal mast cells correlate with angiogenesis and poor outcome in stage I lung adenocarcinoma.

Adenocarcinoma↗
PubMed2001

Danish Anaesthesia Allergy Centre - preliminary results.

BACKGROUND: Anaphylactoid reactions in anaesthesia are rare and should ideally be investigated in specialist centres. At Gentofte University Hospital, we established such a centre in 1998 as a joint venture between the Departments of Anaesthesiology and Dermatology. We present the methodology, diagnostic algorithm and preliminary results from our centre. METHODS: We are open for referral of patients from all of Denmark. Reactions are classified using a three-grade severity scale and all reactions ranging from mild to severe are investigated. Investigations follow a standard step-by-step protocol of in vitro testing and skin testing. Blood samples for tryptase analysis are taken at the time of reaction and a control sample is taken together with samples for specific IgE analysis 2-4 weeks after the reaction. Subsequent skin testing comprises both prick tests and intradermal tests in most cases. Patients are tested with all substances they were exposed to, including antibiotics, colloids, latex and chlorhexidine. RESULTS: A total of 68 patients have been referred to date (July 2001) and 36 have completed investigations. Positive test results were mainly seen in patients with more severe reactions, and there were more men than women in the group with the most severe reactions. Six patients had positive specific IgE, three for penicillin, two for latex and one for thiopental. In all, 21 patients had positive skin tests to various substances, of whom four men with anaphylactic shock tested positive for chlorhexidine. Only one patient has tested positive to a neuromuscular blocking drug (NMBD) so far. DISCUSSION: Our preliminary results appear to differ in two ways from results usually found in this field. Firstly, only one patient has tested positive for a NMBD and secondly, we have had four patients with anaphylactic shock who have tested positive for chlorhexidine. Possible reasons for these differences are discussed.

Adolescent↗
PubMed2003

Matrix metalloproteinases and their inhibitors in gingival mast cells in persons with and without human immunodeficiency virus infection.

BACKGROUND: Mast cells are a prominent cell type in the gingival infiltrate in periodontitis. In this study we examined the expression by gingival mast cells of matrix metalloproteinases, MMP-1, MMP-2, MMP-8 and the tissue inhibitors of metalloproteinases, TIMP-1 and TIMP-2. METHODS: Gingival specimens from 12 human immunodeficiency virus-negative (HIV-) and 15 HIV-positive (HIV+) patients with chronic marginal periodontitis (CMP), and from 10 HIV- and four HIV+ controls with clinically healthy gingiva (HG) were examined after double immunofluorescence staining for mast cell tryptase, combined with antibodies for MMP-1, MMP-2, MMP-8 or their inhibitors TIMP-1 and TIMP-2. RESULTS: In the HIV+CMP, HIV+HG and HIV-CMP groups, all mast cells expressed MMP-1 and MMP-8, whereas a smaller proportion (40-60%) in the HIV-HG controls displayed such staining. The former groups also displayed a significantly higher proportion (39-64%) of mast cells expressing MMP-2 as compared with the HIV-HG group (21-31%). All groups displayed similar proportions of TIMP-1 expressing mast cells (86-100%), whereas significantly increased proportions of TIMP-2+ mast cells were seen in the HIV+CMP, HIV+HG and HIV-CMP groups (18-25%) as compared with the HIV-HG group (8-13%). Mast cells were the cell type that most prominently expressed MMP-1 and MMP-8. MMP-2 expression was also strong in mast cells, but was also similarly expressed in other cell types. CONCLUSION: The chronically inflamed periodontal lesions in the present study appeared with little evidence of mast cell degranulation. The results show, however, that mast cells in inflamed gingiva have the potential to degrade extracellular matrix if appropriately triggered.

Adult↗
PubMed2003

Distribution of immunocompetent cells in decidua of controlled and uncontrolled (choriocarcinoma/hydatidiform mole) trophoblast invasion.

PROBLEM: Pregnancy has been considered as a model of successfully controlled tissue invasion where trophoblast cells infiltrate the maternal decidua without being rejected or without destroying the tissue. In choriocarcinoma (CC) and hydatidiform mole (HM), a dysregulation of invasive (malignant/benign) trophoblast cells is present. Immunocompetent cells (IC) are known to be involved in rejection pathways of malignant cells and can also be identified in early pregnancy decidua. The aim of the present study was to identify the phenotype of IC in decidua of women with normal pregnancy (NP), CC and HM. METHODS: Immunocompetent cells were detected by immunohistochemistry in decidual tissue from first trimester NP (n = 10), CC (n = 12) and HM (n = 11) using antibodies against CD8+, CD3+, CD56+, CD68+ cell surface markers and mast cell tryptase (MCT). A scaled eye piece was used for cell counting to obtain semiquantitative results. Statistical analysis was performed using Wilcoxon rank/Mann-Whitney tests. RESULTS: We observed a significantly increased number of lymphocytes positive for CD8, CD3 and MCT positive granulocytes in CC and HM compared with the samples from NP (all P < or = 0.001). Lymphocytes positive for natural killer (NK) cell marker CD56 were significantly decreased in CC and HM versus NP (P < or = 0.001). The number of CD68 positive cells (macrophages) were not significantly different among the tissue pools. CONCLUSION: The increase of CD8/CD3 T cells and mast cells in CC and HM and the decrease of CD56 cells, compared with NP, suggests the necessity of a balance between T and NK cells in controlling trophoblast invasion.

Adult↗
PubMed2005

Molecular characterization of the idiopathic hypereosinophilic syndrome (HES) in 35 French patients with normal conventional cytogenetics.

Idiopathic hypereosinophilic syndrome (HES) characterized by unexplained and persistent hypereosinophilia is heterogeneous and comprises several entities: a myeloproliferative form where myeloid lineages are involved with the interstitial chromosome 4q12 deletion leading to fusion between FIP1L1 and PDGFRA genes, the latter acquiring increased tyrosine kinase activity. And a lymphocytic variant, where hypereosinophilia is secondary to a primitive T lymphoid disorder demonstrated by the presence of a circulating T-cell clone. We performed molecular characterization of HES in 35 patients with normal karyotype by conventional cytogenetic analysis. TCRgamma gene rearrangements suggesting T clonality were seen in 11 (31%) patients, and FIP1L1-PDGFRA by RT-PCR in six (17%) of 35 patients, who showed no evidence of T-cell clonality. An elevated serum tryptase level was observed in FIP1L1-PDGFRA-positive patients responding to imatinib, whereas serum IL-5 levels were not elevated in T-cell associated hypereosinophilia. Sequencing FIP1L1-PDGFRA revealed scattered breakpoints in FIP1L1-exons (10-13), whereas breakpoints were restricted to exon 12 of PDGFRA. In the 29 patients without FIP1L1-PDGFRA, no activating mutation of PDGFRA/PDGFRB was detected; however; one patient responded to imatinib. FISH analysis of the 4q12 deletion was concordant with FIP1L1-PDGFRA RT-PCR data. Further investigation of the nature of FIP1L1-PDGFRA affected cells will improve the classification of HES.

Adolescent↗
PubMed2002

Mast cell-fibroblast interactions: human mast cells as source and inducers of fibroblast and epithelial growth factors.

As mast cells have been implicated in cutaneous repair processes, we have examined the ability of human mast cells to produce important epithelial and fibroblast growth factors or to stimulate the production of such factors in dermal fibroblasts. Isolated, highly purified human dermal mast cells and human leukemic mast cells were examined for mRNA and partly also for protein expression of these molecules as such or after preincubation with interleukin-4, stem cell factor, or with phorbol myristate acetate. In addition, mast cells were studied for their ability to induce fibroblast growth factor 2 and fibroblast growth factor 7 secretion from dermal fibroblasts. Both dermal and leukemic mast cells expressed fibroblast growth factor 2, fibroblast growth factor 7, and heparin-binding epidermal growth factor, but not hepatocyte growth factor at mRNA level, and dermal mast cells expressed fibroblast growth factor 10 in addition. At protein level, spontaneous fibroblast growth factor 2 secretion was noted that was markedly enhanced by phorbol myristate acetate, whereas no fibroblast growth factor 7 protein was detected under these conditions. Instead, human mast cell-1 supernatants induced enhanced fibroblast growth factor 7 secretion from dermal fibroblasts, with phorbol-myristate-acetate-stimulated supernatants being more effective. This effect could be reproduced with histamine and was H1-receptor mediated. Tryptase was ineffective but stimulated instead fibroblast growth factor 2 secretion from fibroblasts. These data demonstrate for the first time the ability of mast cells to express and/or secrete several growth factors of the fibroblast growth factor family as well as heparin-binding epidermal growth factor directly or indirectly via stimulation of fibroblasts, underlining the potentially pivotal role of these cells during human tissue repair and homeostasis.

Cell Communication↗
PubMed2002

Intra-epithelial CD8+ T cells and basement membrane disruption in oral lichen planus.

BACKGROUND: We investigated basement membrane (BM) disruption and the distribution of mast cells (MCs) and T cell subsets, in oral lichen planus (OLP) and normal buccal mucosa (NBM) using immunohistochemistry. In OLP, there were increased numbers of tryptase+ MCs in areas of BM disruption (P < 0.05). METHOD: We identified clusters of intraepithelial CD8+ T cells in OLP, specifically in regions of BM disruption. The number of intraepithelial CD8+ T cells in regions of BM disruption was significantly greater than in regions of BM continuity (P < 0.05). RESULTS: There were comparable numbers of lamina propria CD8+ T cells in regions of BM disruption and BM continuity. The number of CD4+ T cells in the epithelium and lamina propria of OLP lesions did not vary between regions of BM disruption and BM continuity. CONCLUSION: These data suggest a role for MCs in epithelial BM disruption in OLP. CD8+ T cells may migrate through BM breaks to enter the OLP epithelium.

Analysis of Variance↗
PubMed2002

Mast cell infiltration correlates with poor prognosis in Hodgkin's lymphoma.

Hodgkin's lymphoma (HL) is characterized by a few Hodgkin, Reed-Sternberg cells (HRS) surrounded by benign cells. We recently reported that mast cells were the predominant CD30L-positive cells in HL tumours, and that they activate HRS in vitro through CD30L-CD30 interaction. Here, we investigated the clinical importance of mast cell infiltration in the tumours of 123 patients. Tumour specimens were stained with a mast-cell-specific antibody that detects tryptase. Mast cells were detected in virtually every case and increasing numbers of mast cells correlated to nodular sclerosis histology (P = 0.008). Patients with higher mast cell infiltration had a worse relapse-free survival (P = 0.01).

CD30 Ligand↗
PubMed1998

Histamine release from bronchoalveolar lavage cells from asthmatic subjects after allergen challenge and relationship to the late asthmatic response.

BACKGROUND: Metachromatic cells obtained from asthmatic subjects demonstrate increased spontaneous and stimulated histamine release in vitro. Their ability to synthesize and store proinflammatory cytokines has focused renewed interest on their role in asthma. OBJECTIVE: The late asthmatic response provides a useful model of clinical asthma. The aim of the study was to examine metachromatic cell derived mediators and histamine releasability in vitro after in vivo allergen exposure in atopic subjects with and without asthma and relate them to the type of physiological response observed. METHODS: Bronchoalveolar lavage (BAL) cells were obtained 4 h after challenge from asthmatics exhibiting a single early response (EAR, n = 5), a dual response (LAR, n = 7), unchallenged (basal, n = 5), atopic non-asthmatic (ANA, n = 6) and non-atopic non-asthmatics (normal, n = 5). BAL histamine and tryptase concentrations and in vitro histamine release (HR) after stimulation with anti-IgE, allergen, A23187, conconavalin A and substance P were compared. RESULTS: Metachromatic cell numbers were lower in normal controls compared with all asthmatic groups and in LAR compared with EAR. Metachromatic cell derived mediators were higher in asthmatic compared with normal subjects. Spontaneous HR in LAR (20.5 +/- 5.0%) was lower than EAR (29.5 +/- 3.9%) and ANA (30.2 +/- 1.4%) (P < 0.05). No differences were seen in stimulated HR between EAR and LAR. HR in ANA stimulated with anti-IgE was greater than LAR (P < 0.05). HR in ANA stimulated with anti-IgE was greater than LAR (P < 0.05). After stimulation with ionophore A23187 (1 microM), release was greater in LAR compared with basal (P < 0.05) and no different at 5 microM. All subject groups responded to substance P (SP) but was significantly more in the asthmatic subjects compared to normal controls (P < 0.05). Allergen challenge did not modify the response of asthmatic subjects to SP. CONCLUSION: Functional differences in metachromatic cell reactivity are present in atopic subjects 4h after in vivo allergen exposure which relate to the physiological response observed after this time and suggest that there is ongoing metachromatic cell degranulation subjects who subsequently develop LAR.

Adolescent↗
PubMed1998

The long-term effects of capsaicin aqueous spray on the nasal mucosa.

BACKGROUND: Capsaicin has been shown previously to reduce nasal complaints in patients with a non-allergic non-infectious perennial rhinitis. Proposed pathophysiological mechanisms for non-allergic non-infectious perennial rhinitis include a chronic inflammatory disorder of an antigenic or neurogenic nature as well as the possibility of a functional neuronal disorder. We hypothesized that the beneficial effect of capsaicin might be the result of a down-regulation of inflammation (by a reduction of inflammatory cells) or through modulation of neural tissue density. METHODS: Patients were treated with either a placebo or capsaicin spray solution delivering 0.15 mg of capsaicin per nostril once every second or third day for a total of seven treatments. Both sides were treated each visit. Biopsies were taken before and 2 weeks, 3 months and 9 months after the treatment period. Immunohistochemical staining of the biopsy specimen was performed to ascertain the effect of treatment on immunocompetent cell densities (quantitative) and neural tissue densities (semi-quantitative) in the nasal mucosa. RESULTS: Nasal complaints were significantly reduced in the capsaicin-treated group. The number of CD1+, CD25+, CD3+, CD68+, BMK13+, IgE+, tryptase+, and chymase+ cells did not significantly differ between capsaicin and placebo group. No significant differences between both groups were found in pan-neurogenic staining of nasal mucosa using neurofilament and synaptophysine. CONCLUSION: Capsaicin aqueous nasal spray has previously been shown to reduce nasal complaints without affecting cellular homeostasis or overall neurogenic staining up to 9 months after treatment. Immunocompetent cells are not involved in non-allergic non-infectious perennial rhinitis.

Administration, Intranasal↗
PubMed2001

The release of histamine is associated with the inactivation of mast cell chymase during immediate allergic wheal reaction in the skin.

BACKGROUND: Chymase released by mast cells can participate in the immediate allergic wheal. However, chymase may be susceptible to inactivation by protease inhibitors during degranulation. OBJECTIVE: To study the inactivation of chymase and the release of histamine in the immediate allergic wheal reaction. METHODS: Ten sensitive atopic subjects were prick-tested with the cow dander allergen, and skin biopsies were taken from the control skin and from the challenge site at 30 and 120 min. Tryptase (Tact) and chymase (Cact) activities in mast cells were measured enzyme-histochemically. Sequential double-staining was used to demonstrate the activity and immunoreactivity (Cprot) of chymase in the same mast cell as well as alpha1-proteinase inhibitor (alpha1-PI) and alpha1-antichymotrypsin (alpha1-AC) in Tact+ cells. Skin microdialysis was used to monitor histamine release after the allergen challenge for up to 120 min RESULTS: The numbers of Tact+ and Cact+ cells were already maximally decreased at 30 min by 37 +/- 17% and 61 +/- 31%, respectively (mean +/- SD, P < 0.0001). At the same time the Cact+/Cprot+ ratio decreased from 82 +/- 15% to 43 +/- 16% (P < 0.0001). The cumulative histamine release at 30 min correlated negatively with the Cact+/Tact+ (P = 0.047) and Cact+/Cprot+ (P = 0.024) ratios, but positively with the decrease in the number of Cact+ cells (P = 0.024). These data indicate that the higher the histamine release the lower the chymase activity. Also the number of Tact+ cells in the control skin correlated positively with the cumulative histamine release at 120 min (P = 0.043). In the control skin, 95 +/- 6% and 76 +/- 8% of the Tact+ cells displayed alpha1-AC and alpha1-PI, respectively. CONCLUSION: In addition to extensive degranulation of mast cells, chymase is also rapidly inactivated after the allergen challenge, possibly by pre-existing chymase inhibitors in the mast cells. This inactivation is associated with the release of histamine.

Adult↗
PubMed2002

Human mast cells stimulate fibroblast proliferation, collagen synthesis and lattice contraction: a direct role for mast cells in skin fibrosis.

BACKGROUND: Mast cells, the key cells of immediate hypersensitivity type reactions, have also been postulated to have a central role in influencing tissue remodelling and fibrosis occurring in the skin. OBJECTIVE: Our aim was to investigate the direct role of human mast cells (HMC) in skin fibrotic processes, by assessing the effects of the addition of the human mast cell line HMC-1 to human skin fibroblasts, and to identify the responsible mediators. METHODS: HMC-1 sonicates were added to human skin fibroblasts and the following parameters were evaluated: proliferation ([3H]-thymidine), collagen synthesis ([3H] proline), activity of matrix metalloproteinases (MMPs) (zymography) and tissue inhibitors of metalloproteinases (TIMPs) (reverse zymography), and collagen gel contraction. RESULTS: HMC-1 sonicate increased significantly both proliferation and collagen production in the human skin fibroblasts and these properties were not affected by heating of the sonicate (56 degrees C, 30 min, or 100 degrees C, 3 min). Two main mast cell mediators, histamine and tryptase, were found to be responsible for the increase in fibroblast proliferation and collagen production. HMC-1 sonicate did not display any pre-formed gelatinase activity, and its addition to the fibroblasts did not change their pro-MMP-2 and MMP-2 activity. On the other hand, HMC-1 were found to possess TIMP-1 and TIMP-2. Addition of HMC-1 had no effect on fibroblasts TIMP-1 but induced a dose-dependent increase of TIMP-2 activity. In addition, HMC-1 sonicate seeded together with the fibroblasts in tri-dimensional collagen gel significantly enhanced their contraction. CONCLUSION: We have shown that human mast cells, by granule-stored and therefore quickly releasable mediators, increase human skin fibroblast proliferation, collagen synthesis, TIMP-2 and collagen gel contraction. Therefore, mast cells have a direct and potentiating role in skin remodelling and fibrosis.

Cell Division↗
PubMed1996

Quantitative assessment of intestinal eosinophils and mast cells in inflammatory bowel disease.

Previous studies on the frequency of intestinal mast cells and eosinophils in patients with inflammatory bowel disease yielded conflicting results. In the present morphometric study, we quantified mast cells and eosinophils in the lamina propria by histological and immunohistochemical methods in 64 patients suffering from Crohn's disease (33 cases) or ulcerative colitis (31 cases), and in 29 controls. Histological data from 206 biopsies were related to the presence of mucosal inflammation and clinical parameters. The number of eosinophils was increased in patients with inflammatory bowel conditions (mean +/- SE: 331 +/- 44/mm2) as compared to controls (258 +/- 27/mm2), and was dependent on disease activity and drug treatment. Mean mast cell numbers did not differ between patients and controls. However, a reduced mast cell number was found in toluidine blue-stained sections of actively inflamed tissue areas (143 +/- 16/mm2, versus 206 +/- 18/mm2 in non-inflamed tissue). Immunohistochemical studies using antibodies against the granule proteins tryptase and chymase suggest that this decrease in mast cell numbers is due to mast cell degranulation. The present data show that the number of intestinal mast cells and eosinophils is altered in patients with inflammatory bowel diseases, suggesting that both cell types are involved in the pathogenesis of chronic intestinal inflammation.

Adult↗
PubMed2004

Montelukast plus cetirizine in the prophylactic treatment of seasonal allergic rhinitis: influence on clinical symptoms and nasal allergic inflammation.

BACKGROUND: The aim of our study was to investigate effects of 6-week pretreatment of seasonal allergic rhinitis (AR) with cetirizine, and montelukast, alone and in combination. Antihistamine/antileukotriene treatment is effective in AR. Antihistamines may prevent AR symptoms while prophylactic activity of antileukotrienes remains unclear. METHODS: Sixty AR patients, aged 18-35 years, were randomized to receive placebo, montelukast only, cetirizine only, or montelukast plus cetirizine, 6 weeks prior and 6 weeks after the beginning of grass pollen season. Mean self-recorded in-season symptom scores and mean weekly all-symptom scores were analyzed. In 31 patients, nasal lavages were performed before treatment, and at the end of the study, i.e. 12 weeks after the treatment initiation. Eosinophil and basophil counts, eosinophil cationic protein (ECP), and mast cell tryptase (MCT) levels were evaluated in lavage samples. RESULTS: Combined montelukast/cetirizine pretreatment significantly reduced in-season symptom score for sneezing, eye itching, nasal itching, rhinorrhea, and congestion. Montelukast plus cetirizine were more effective than cetirizine alone in preventing eye itching, rhinorrhea, and nasal itching. Moreover, combined pretreatment with montelukast and cetirizine delayed appearance of AR symptoms. Eosinophil nasal lavage fluid counts were significantly increased during pollen season in placebo and montelukast-only groups. No differences were observed in basophil counts. The in-season ECP level was significantly increased in all groups except montelukast-plus-cetirizine group. In-season MCT levels were not increased. CONCLUSION: Combined antihistamine and antileukotriene treatment started 6 weeks before the pollen season is effective in preventing AR symptoms and reduces allergic inflammation in nasal mucosa during natural allergen exposure.

Acetates↗