Rational design of hypoallergens applied to the major cat allergen Fel d 1

BACKGROUND: Allergen-specific immunotherapy is the only treatment for allergic disease providing long-lasting symptom relief. Currently, it is mainly based on the use of crude allergen extracts. The treatment may be improved by the use of genetically engineered allergens, hypoallergens, aiming at a more effective and safer therapy. OBJECTIVE: The aim of this study was to provide a rational design of hypoallergen candidates for immunotherapy by using structural information and knowledge of B and T cell epitopes of an allergen. METHODS: The three-dimensional structure of the major cat allergen Fel d 1 was systematically altered by duplication of selected T cell epitopes and disruption of disulphide bonds. Seven Fel d 1 derivatives were generated and screened for allergenic reactivity in comparison with recombinant Fel d 1 in competition-ELISA. The allergenicity was further evaluated in basophil activation experiments and T cell reactivity was assessed in a lymphoproliferation assay. RESULTS: Three out of seven Fel d 1 derivatives, with two duplicated T cell epitopes and one or two disulphide bonds disrupted, were carefully evaluated. The three derivatives displayed a strong reduction in allergenicity with 400-900 times lower IgE-binding capacity than recombinant Fel d 1. In addition, they induced a lower degree of basophil activation and similar or stronger T cell proliferation than recombinant Fel d 1. CONCLUSION: By a rational approach, we have constructed three Fel d 1 hypoallergens with reduced IgE-binding capacities and retained T cell reactivities. This strategy may be applied to any well-characterized allergen to improve immunotherapy for allergic patients.     

Poor association between allergen-specific serum immunoglobulin E levels, skin sensitivity and basophil degranulation: a study with recombinant birch pollen allergen Bet v 1 and an immunoglobulin E detection system measuring immunoglobulin E capable of binding to FcɛRI

BACKGROUND: Results from several studies indicate that the magnitude of immediate symptoms of type I allergy caused by allergen-induced cross-linking of high-affinity Fc epsilon receptors on effector cells (mast cells and basophils) is not always associated with allergen-specific IgE levels. OBJECTIVE: To investigate the association of results from intradermal skin testing, basophil histamine release and allergen-specific IgE, IgG1-4, IgA and IgM antibody levels in a clinical study performed in birch pollen-allergic patients (n = 18). METHODS: rBet v 1-specific IgEs were measured by quantitative CAP measurements and by using purified Fc epsilon RI-derived alpha-chain to quantify IgE capable of binding to effector cells. Bet v 1-specific IgG subclasses, IgA and IgM levels were measured by ELISA, and basophil histamine release was determined in whole blood samples. Intradermal skin testing was performed with the end-point titration method. RESULTS: Our study demonstrates on the molecular level that the concentrations of allergen-specific IgE antibodies capable of binding to Fc epsilon RI and biological sensitivities are not necessarily associated. A moderate association was found between cutaneous and basophil sensitivity. CONCLUSION: Our results highlight the quantitative discrepancies and limitations of the present diagnostic tools in allergy, even when using a single allergenic molecule. The quantity of allergen-specific serum IgE is only one component of far more complex cellular systems (i.e. basophil-based tests, skin tests) used as indirect diagnostic tests for IgE-mediated allergic sensitivity.     

Influence of mattress characteristics on house dust mite allergen concentration

BACKGROUND: Exposure to a high level of house dust mite allergens (HDMAs) is considered as a risk factor for HDM sensitization and development of asthma in genetically disposed people. Mattresses are one of the most important sources of HDMA in people's living environment. OBJECTIVE: The aim of this study was to evaluate the association between mattress characteristics and HDMA concentrations on mattresses. METHODS: Dust samples of mattress surfaces were taken to evaluate the level of Der p 1 allergen. All participants filled in a questionnaire about the type of mattress, the type of covering (upper layer) of the mattress, dwelling characteristics and cleaning habits. Humidity and temperature of the bedroom were measured at the time of dust sampling. RESULTS: One hundred and sixty-eight questionnaires were filled in. Synthetic upper layer of the mattress was associated with a higher level of Der p 1 compared with cotton upper layer (2.6 vs. 0.8 microg/g Der p 1). Moreover, higher relative humidity (RH) was associated with significant higher concentrations and density of Der p 1. CONCLUSIONS: Two factors were associated with lower levels of Der p 1 found on mattresses, namely: a cotton upper layer of the mattress compared with a layer of synthetic material and lower RH at the time of sampling. As far as we know, the association between type of upper layer and concentration of Der p 1 has not been described before and could lead to the formulation of practical advices in order to reduce HDMA concentrations on mattresses.     

Synthesis,AM<Subscript>1</Subscript> calculation,and biological studies of thiopyran-4-one and their azine derivatives

Some novel N(1)-arylidene-N(2)-cis-2,6-diphenyltetrahydrothiopyran-4-one azine derivatives were synthesised and their antibacterial activity against Streptococcus faecalis, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus and antifungal activity against Candida-6, Candida-51, Aspergillus niger, and Aspergillus flavus were evaluated.     

Peripheral T-cell lymphoma in childhood. A clinicopathological study of six cases

A review of the pathological material from 42 children with non-Hodgkin's lymphoma seen over a 44 month period revealed 10 large cell tumours. Of these, six were classified as peripheral T-cell lymphoma, an entity rarely reported in childhood. Three patients were boys and three girls (median age 9.5 years), and extranodal presentation was a feature of two patients. Five had high-grade tumours; of these, three were classified as large cell anaplastic, Ki-1 positive and two as pleomorphic large cell. The remaining patient had a low-grade tumour of angioimmunoblastic type. T-cell subsets were examined in three cases and showed the following phenotypes: CD4-, CD8-; CD4+, CD8-; CD4-, CD8+. Three of the patients with high-grade tumours died, with a mean survival of 22 weeks. The remaining patients are alive and clinically disease-free for between 10 and 24 months after treatment.     

Expression of Anion Exchanger 1 Sequestrates p16 in the Cytoplasm in Gastric and Colonic Adenocarcinoma

p16^INK4A (p16) binds to cyclin-dependent kinase 4/6 and negatively regulates cell growth. Recent studies have led to an understanding of additional biologic functions for p16; however, the detailed mechanisms involved are still elusive. In this article, we show an unexpected expression of anion exchanger 1 (AE1) in the cytoplasm in poorly and moderately differentiated gastric and colonic adenocarcinoma cells and in its interaction with p16, thereby sequestrating the protein in the cytoplasm. Genetic alterations of p16 and AE1 were not detectable. Forced expression of AE1 in these cells sequestrated more p16 in the cytoplasm, whereas small interfering RNA-mediated silencing of AE1 in the cells induced the release of p16 from the cytoplasm to the nucleus, leading to cell death and growth inhibition of tumor cells. By analyzing tissue samples obtained from patients with gastric and colonic cancers, we found that 83.33% of gastric cancers and 56.52% of colonic cancers coexpressed AE1 and p16 in the cytoplasm. We conclude that AE1 plays a crucial role in the pathogenesis of gastric and colonic adenocarcinoma and that p16 dysfunction is a novel pathway of carcinogenesis.     

Th1/Th2炎症极化与肺气肿和肺纤维化

肺气肿具有Ⅰ型T辅助细胞（Th1）炎症极化的特征，表现为损伤过度和修复不足，肺实质的破坏增加，肺间质变薄。与之相反，肺纤维则具有Ⅱ型T辅助细胞（Th2）炎症极化，表现为损伤后修复过度，肺间质增厚，胶原沉积。通过调控Th1和Th2的炎症趋势来控制肺组织的损伤和修复的结局可能会为肺气肿和肺纤维化的防治提供新思路。     

Effect of divalent cations on structure-function relationships of the antitumor protein α-sarcin

α-Sarcin binds one Zn(II) cation per protein molecule, with a K_d value of 0.9 mM, determined by equilibrium dialysis experiments. Ca(II), Mg(II), and Mn(II) do not bind to α-sarcin. Cd(II) and Co(II) also behave as Zn(II). The binding produces local modifications on the protein conformation affecting the microenvironment of tryptophan residues. The three cations modify the fluorescence emission of the protein. The near-u. v. circular dichroism spectrum of the protein is also altered. The binding of Zn(II) and related cations does not modify the secondary structure of the protein. The ribonucleolytic activity of a-sarcin is inhibited upon Zn(II) binding, but no alteration of the ability of the protein to aggregate phospholipid vesicles has been observed.     

Expression of alpha-defensin-1 in chronic hyperplastic candidosis

BACKGROUND: Chronic hyperplastic candidosis (CHC) represents a chronic opportunistic candida infection. We clarified the presence, localization and participation of alpha-defensin-1 in host response against chronic candidal stimulus. METHODS: Immunohistochemically stained CHC biopsies (n = 10) were compared to candida negative idiopathic leukoplakia (n = 10). RESULTS: In CHC alpha-defensin-1 was detected in neutrophils intravascularly, in lamina propria and in the epithelium, in part in intraepithelial microabscesses. Staining intensity of individual neutrophils varied and was associated with peri- and extracellular staining, in particular in the superficial epithelial cell layers. In controls only very few homogeneously staining neutrophils were detected intravascularly without any extracellular alpha-defensin-1 deposition. CONCLUSIONS: Neutrophils form microabscesses and respond to Candida by activation and release of alpha-defensin-1 to peri- and extracellular matrix. This together with the epithelial cell migration from the basal layer to epithelial surface leads to alpha-defensin-1 rich protective shield in the most superficial epithelial cell layers.     

食管癌患者血缘亲属及不同性别食管癌患病风险比较研究

目的 对比分析食管癌病例组与对照组血缘亲属食管癌患病风险,并了解食管癌家族中危险亲属人群患病的新线索.方法 采用病例对照研究方法 ,对食管癌病例组及对照组各720例进行逐层分析,以比较两组各血缘亲属父系、母系食管癌患病危险度(OR)的大小及差异.结果 (1)病例组Ⅰ级亲属食管癌患病危险度(1.34%～2.24%)显著高于对照组(0.78%～1.21%)(P＜0.01);Ⅰ级亲属中病例组父母亲食管癌患病危险度为6.11%,显著高于对照组父母亲食管癌患病危险度2.97%(P＜0O01).(2)以血缘亲属中父系和母系亲属逐层分析可见,病例组父系食管癌患病危险度(0.87%～1.01%)与母系患病危险度(0.50%～0.79%)均显著高于对照组父系食管癌患病危险度(0.53%～0.65%)与母系患病危险度(0.38%～0.47%)(P＜0.05).进一步分析显示,病例组父系中男性亲属与母系中女性亲属,即父系中祖父、父亲、叔伯食管癌患病危险度为2.68%与母系中外祖母、母亲、姨的食管癌患病危险度1.91%均显著高于对照组父系中男性亲属食管癌患病危险度1.50%与母系中女性亲属食管癌患病危险度0.92%(P＜0.01).结论 山西省食管癌患者血缘亲属发病危险主要是父亲及其兄弟、母亲及其姐妹,其下代患食管癌风险要大.