A 5-Year Open-Label Follow-up of a Randomized Double-Blind Placebo-Controlled Trial of Intralymphatic Immunotherapy for Birch and Grass Allergy Reveals Long-term Beneficial Effects.

BACKGROUND: Intralymphatic immunotherapy (ILIT) is a novel, faster alternative to conventional allergen immunotherapy (AIT). Few previous studies have evaluated its long-term effects. The objective of the present study was to complete a 5-year follow-up of a randomized double-blind placebo-controlled trial of ILIT for a combination of birch and grass allergens. METHODS: Fifty-eight patients with allergic rhinitis were treated with either placebo or a combination of ALK Alutard Birch and Grass 1000 SQ-U administered in 3 intralymphatic injections at 1-month intervals. A year after the vaccination, the symptoms induced by nasal provocation were significantly reduced. After 5-6 years, 20 out of 26 actively treated patients were followed up with a nasal provocation test (NPT) and seasonal registration of the combined symptom and medications score (CSMS), IgE and IgG4 levels in blood, and immunological markers in blood and lymph nodes and compared with 13 unvaccinated controls. RESULTS: The reduction in the NPT response with ILIT at year 1 could not be convincingly reproduced at year 5. The new CSMS scores were markedly lower among the previously treated patients than among the control group. Furthermore, grass-specific IgG4 was increased, grass-specific IgE decreased, FcεR1 on basophils was reduced, and the fraction of memory T-cells in lymph nodes increased. CONCLUSION: The combination of seasonal clinical data and immunological parameters supports the notion of a long-lasting effect of ILIT. These data support the concept of ILIT as a good alternative to traditional AIT in pollen-induced allergic rhinitis.

Airway inflammation evaluated in a human nasal lipopolysaccharide challenge model by investigating the effect of a CXCR2 inhibitor.

BACKGROUND: The existence of a link between inflammation in upper and lower airways is well established. It may therefore be assumed that the nose could be used to study inflammatory events in the lower airways. OBJECTIVE: This study aimed to evaluate a lipopolysaccharide (LPS) nasal challenge model by investigating the effect of the CXCR2 inhibitor AZD8309 on neutrophilic inflammation. METHODS: A total of 18 healthy volunteers were randomized in a placebo-controlled, double-blind, cross-over study. AZD8309 or placebo was dosed for 3 days. Subjects were challenged nasally with LPS (50 µg/nostril), and nasal lavage was performed 6 and 24 h later. Leucocytes, neutrophils and inflammatory mediators were assessed in the lavage fluid. The outcome was compared with data from analogous experiments performed in a model of inhaled LPS followed by induced sputum. This trial was registered in the Current Controlled Trials register (ISRCTN trial number: ISRCTN46666382). RESULTS: The leucocytes in nasal lavage consisted to 99% of neutrophils on average. Treatment with AZD8309 reduced the leucocyte count to 48% of placebo 6 h after the LPS challenge. There was also a reduction in LTB4 levels to 45% of placebo after 6 h and in the neutrophil elastase activity after 24 h. No major adverse events were seen with either AZD8309 or placebo. The nasal LPS model induced only minimal local irritation and no signs of systemic inflammation. CONCLUSIONS AND CLINICAL RELEVANCE: LPS-induced neutrophil recruitment was reduced by inhibition of CXCR2. This outcome mimicked the response previously seen in a lower airway LPS model. Hence, the nasal model offers a convenient and well-tolerated alternative for pharmacological evaluation of anti-inflammatory drugs affecting neutrophilic migration and activity.

An association between Type 2 diabetes and alpha-antitrypsin deficiency.

AIMS: Alpha(1)-Antitrypsin (AAT) is a serine protease inhibitor which recently has been shown to prevent Type 1 diabetes development, to prolong islet allograft survival and to inhibit pancreatic B-cell apoptosis in vivo. It has also been reported that Type 1 diabetic patients have significantly lower plasma concentrations of AAT, suggesting the potential role of AAT in the pathogenesis of Type 1 diabetes. We have investigated whether plasma AAT levels are altered in Type 2 diabetes. METHODS: The study included patients with Type 2 diabetes (n = 163) and non-diabetic control subjects matched for age, sex and smoking habits (n = 158) derived from the population-based Malmö Diet and Cancer study. Plasma samples were analysed for AAT concentration and phenotype and serum glucose, insulin, C-reactive protein and lipid levels were measured. Glycated haemoglobin was also measured. RESULTS: In the diabetic group, the women had higher mean plasma AAT levels than men (P < 0.05). The mean plasma AAT levels did not differ between diabetic and control subjects. However, the number of individuals with low AAT levels (< 1.0 mg/ml) was 50% higher in the diabetic group (P < 0.05) and the frequency of AAT deficiency genotypes was 50% higher (NS) in diabetic compared with control subjects. In the group of diabetic patients with AAT < 1 mg/ml, AAT directly correlated with systolic blood pressure (P = 0.048) and inversely correlated with waist-hip ratio (P = 0.031). CONCLUSIONS: Our results provide evidence that deficiency of AAT may be associated with an increased risk of developing Type 2 diabetes.

The presence of elafin, SLPI, IL1-RA and STNFalpha RI in head and neck squamous cell carcinomas and their relation to the degree of tumour differentiation.

Biopsy samples of head and neck carcinomas were investigated with regard to elafin, secretory leukocyte protease inhibitor (SLPI), interleukin 1-receptor antagonist [(IL)1-RA] and soluble tumour necrosis factor alpha receptor antagonist (STNFalpha RI). SLPI and elafin are serine protease inhibitors produced in the serous cells of the upper respiratory airways and in the keratinocytes, respectively. We have now found the presence of elafin and SLPI in squamous cell carcinomas of the upper respiratory tract (tonsillar, hypopharyngeal, tongue, mouth floor, gingival and laryngeal cancer). Significantly higher amounts of SLPI and elafin are present in well-differentiated and moderately differentiated tumours than in poorly differentiated tumours (p < 0.0001 and p < 0.0015). Tumour necrosis factor-alpha and IL-1beta have been shown to stimulate the production of SLPI and elafin. Since these cytokines can both be difficult to detect, we chose to study their inhibitors, STNFalpha RI and IL1-RA, instead. IL1-RA was expressed in highly differentiated tumours as well as in poorly differentiated ones. No significant difference was seen between the groups. STNFalpha RI was only found in very small amounts, sparsely distributed in the tumours, and was not related to the degree of differentiation.

Secretory leukocyte protease inhibitor in punch biopsies from human colonic mucosa.

Secretory leukocyte protease inhibitor (SLPI) is a well-known protease inhibitor. Its function is thought to be protease/protease-inhibitor balance. Free proteolytic activity, mainly pancreatic elastase, anionic trypsin and granulocytic elastase, has been demonstrated in faecal extracts from patients with ulcerative colitis. We wanted to verify that SLPI is actually secreted from normal human colonic mucosa. Also, we wanted to ascertain whether studies of SLPI secretion based on punch biopsies were dependent on biopsy area or on biopsy circumference. Normal colonic mucosa was sampled during surgery for colonic cancer. A total of 36 samples from four patients were used. Mucosa preparation was carried out using a punch biopsy technique, and samples of 3, 4 and 6 mm diameter were used. All media contained SLPI at varying concentrations. When expressed in terms of the sample area, the secretion per millimetre-squared seemed to decrease with increasing area. When calculated as secretion per circumference, secretion seemed to be constant. In conclusion, SLPI was secreted from normal human colonic mucosa. The SLPI secretion seemed dependent on the circumference of the biopsy rather than on the area of the biopsy.

The effect of immediate-hypersensitivity reactions on the level of SLPI, granulocyte elastase, alpha1-antitrypsin, and albumin in nasal secretions, by the method of unilateral antigen challenge.

BACKGROUND: The aim of this paper was to investigate the role of SLPI in patients with allergic rhinitis. From this point of view, we also examined leukocyte elastase, alpha1-antitrypsin, and albumin. SLPI is an inhibitor of serine proteases such as leukocyte elastase, cathepsin G, and mast-cell chymase. Since chymase is considered to participate in mast-cell degranulation and histamine release, SLPI might act as a regulator of allergic reactions. Recent interest has been focused on leukocytes and allergy. Since SLPI is a strong inhibitor of leukocyte elastase, we also focused on the function of elastase in allergic rhinitis. METHODS: We used the method of nasal lavage after unilateral nasal antigen challenge in atopic and healthy subjects. The ELISA quantified SLPI and elastase. Albumin and alpha1-antitrypsin were quantified by electroimmunoassay. Gel filtration was used to separate native SLPI from its complex with elastase. RESULTS: There was a higher level of SLPI in lavage fluid from healthy subjects than from atopic patients. SLPI was increased on the contralateral side in atopic subjects after allergen challenge. The absence of increase in SLPI on the challenged side may be attributed to the increase in elastase and its binding to SLPI, which might have an effect on the immunoreactivity and interfere with the ELISA. It may then be assumed that there is an augmentation of SLPI on the challenged side as well. No increase was seen in healthy subjects. There was a higher concentration of elastase, alpha1-antitrypsin, and albumin before antigen challenge in atopic patients outside the pollen season than in healthy subjects. As expected, an increase was also seen in the challenged side exclusively in atopic subjects. CONCLUSIONS: The lower concentration of SLPI in nasal lavage fluid among the atopic patients than the healthy subjects indicates damaged mucosa. Neural reflexes are involved in SLPI release since there was an increase even in the contralateral nostril. A higher level of elastase and albumin before allergen challenge suggests chronic inflammation in nasal mucosa outside the pollen season. Leukocyte recruitment takes place in response to IgE-mediated reactions, which are reflected in an increase in elastase in response to allergen challenge.

Identification of SLPI (secretory leukocyte protease inhibitor) in human mast cells using immunohistochemistry and in situ hybridisation.

Recently interest has been focused on secretory leucocyte protease inhibitor (SLPI) and its role in immediate hypersensitive reactions, possibly by inhibiting mast cell chymase. The purpose of this investigation was to show whether or not SLPI is produced in mast cells. Double-immunolabelling revealed that SLPI coexists with mast cell tryptase (60%) and chymase (37%). On the other hand, in situ hybridisation studies demonstrated the expression of SLPI mRNA in all mast cells. The differences in results can be attributed to the fact that in situ hybridisation is a more sensitive method than immunohistochemistry. Hence, we conclude that SLPI is produced in human tonsillar mast cells.

IgE-mediated histamine release from nasal mucosa is inhibited by SLPI (secretory leukocyte protease inhibitor) to the level of spontaneous release.

The secretory leukocyte protease inhibitor (SLPI) is a low-molecular-weight inhibitor of proteases, such as elastase and cathepsin G which are released from leukocytes during phagocytosis. The purpose of this study was to determine whether or not SLPI is able to inhibit IgE-mediated histamine release. Nasal mucosa from 11 test subjects without atopic disposition was used for this in vitro study. We found that SLPI inhibited histamine release in a dose-dependent way but was without influence on the spontaneous release.

Localisation of secretory leucocyte proteinase inhibitor mRNA in nasal mucosa.

Human secretory leucocyte proteinase inhibitor (SLPI) is a low-molecular weight, acid-stable inhibitor of polymorph-nuclear granulocyte elastase and cathepsin G. Previous reports have demonstrated the existence of SLPI in the respiratory tract, salivary glands and cervical mucosa. Positive staining for SLPI using immunohistochemical techniques has been reported in serous glands in nasal mucosa. We now confirm this observation and show, using in situ hybridization, that the pattern of expression of mRNA corresponds to the distribution of the encoded protein, SLPI. This, together with the high concentration of SLPI in nasal secretions, confirms the hypothesis of a local production of SLPI in the mucous membranes.