KIR2DL3 and the KIR ligand groups HLA-A-Bw4 and HLA-C2 predict the outcome of hepatitis B virus infection.

Killer immunoglobulin-like receptors (KIRs) regulate the activation of natural killer cells through their interaction with human leucocyte antigens (HLA). KIR and HLA loci are highly polymorphic, and certain HLA-KIR combinations have been found to protect against viral infections. In this study, we analysed whether the KIR/HLA repertoire may influence the course of hepatitis B virus (HBV) infection. Fifty-seven subjects with chronic hepatitis B (CHB), 44 subjects with resolved HBV infection and 60 healthy uninfected controls (HC) were genotyped for KIR and their HLA ligands. The frequency of the HLA-A-Bw4 ligand group was higher in CHB (58%) than subjects with resolved infection (23%) (crude OR, 4.67; P<.001) and HC (10%) (crude OR, 12.38; P<.001). Similar results were obtained for the HLA-C2 ligand group, more frequent in CHB (84%), than subjects with resolved infection (70%) (crude OR, 2.24; P<.10) and HC (60%) (crude OR, 3.56; P<.01). Conversely, the frequency of KIR2DL3 was lower in CHB (81%) than in subjects with resolved infection (98%) (crude OR, 0.10; P<.05). These results suggest a detrimental role of HLA-A-Bw4 and HLA-C2 groups, which are associated with the development of CHB, and a protective role of KIR2DL3. A stepwise variable selection procedure, based on multiple logistic regression analysis, identified these three predictive variables as the most relevant, featuring high specificity (90.9%) and positive predictive value (87.5%) for the development of CHB. Our results suggest that a combination of KIR/HLA gene/alleles is able to predict the outcome of HBV infection.

Cyclooxygenase-2 expression in oral squamous cell carcinoma.

Cyclooxygenase (COX), the key enzyme in prostaglandin cascade, is expressed in two isoforms: the constitutive COX-1 and the inducible COX-2. Hyper-expression of COX-2 has been implicated in the pathogenesis of colon-rectal cancer in humans but it appears to play a significant role as a tumour progression factor also in other forms of human cancer, including oral cancer. The aim of this study was to analyze the expression of COX-2, at the protein level, in 45 cases of oral squamous cell carcinoma. Standard immunohistochemical streptavidin-biotin peroxidase analysis was carried out with highly specific antibody against human COX-2 and cell specific markers, in 45 oral squamous cell carcinomas. Our study revealed a moderate to high COX-2 expression in 35 out of the 45 oral squamous cell carcinoma specimens (77.8%). COX-2 expression appeared particularly abundant in the superficial ulcerated layers of relatively well differentiated carcinomas. However, we were unable to assess any statistically significant association between COX-2 hyper-expression and tumor site, tumor grading, tumor size, presence of lymph node metastases, tumor stage and age at onset, respectively. Interestingly, COX-2 expression was detected not only in areas of epithelial dysplasia adjacent to the primary layers (86% of the cases) but also in normal-appearing epithelium at the boundaries of squamous cell carcinoma (77%), indicating a possible involvement in tumour progression by the apparently normal tissue surrounding the lesion. Moreover, intense COX-2 staining was observed in endothelial cells of intra-tumour vessels and extra-tumour vessels adjacent to the tumour nests, in a high proportion of cases (82%). COX-2 positivity was associated with CD34 and VEGF positivity, indicating that these vessels were probably neo-formed ones. From this study as well as from other works, it appears that indeed COX-2 is over-expressed in this important human malignancy. However, further studies are necessary to understand the exact magnitude of this over-expression and, mostly, the possible role of COX-2 in the pathogenesis and progression of oral cancer.

Grape anaphylaxis.

Grape allergy is particularly rare in spite of the vast extension of Vitis vinifera cultivation on all continents. We report on the case of a 28-year-old woman who presented with allergic systemic reaction after eating white grapes (Vitis vinifera). She complained of two severe episodes of anaphylaxis after eating grapes, with generalized pruritus, acute generalized urticaria, facial swelling, lip and oropharingeal angioedema, and dysphagia. Both the episodes were treated at the Emergency Room level, with parenteral administration of corticosteroids and antihistamines. Skin prick tests with commercial extract of grapes provided a negative result, while prick by prick procedure performed with white grapes and white grape juice yielded a positive result. Grape-specific serum IgE were also detected. We conclude that in the diagnosis of grape allergy the currently available commercial extracts might not be completely reliable and the prick-by-prick procedure with fresh grapes should always be performed.

Multicenter double-blind comparative study of terfenadine and cetirizine in hay fever.

The efficacy and safety of terfenadine in the management of hay fever were compared with those of cetirizine in a multicenter, double-blind, parallel-group study, carried out during the 1990 spring pollen season. The patients were randomly assigned to one of two groups of treatment, 70 patients being given terfenadine 120 mg, and 72 patients cetirizine 10 mg, once daily for 7 days. The severity of the main symptoms was evaluated at baseline and after treatment by a 4-point rating scale. In addition, the overall symptom severity was recorded daily by the patient on a diary card. Both terfenadine and cetirizine produced significant relief of symptoms by the end of treatment, with a decrease in symptom severity ranging from 46 to 69% for terfenadine and from 40 to 55% for cetirizine. Adverse effects experienced by terfenadine- and cetirizine-treated patients were mainly drowsiness, with minor differences between the two groups. The results of this study confirmed previous experiences, showing that both terfenadine and cetirizine once daily should be regarded as effective drugs for the management of hay fever.

Italian real-life experience of omalizumab.

Omalizumab is a humanized murine monoclonal antibody directed toward a portion of the IgE indicated in Europe for the treatment of severe persistent allergic asthma, inadequately controlled despite high-dose of ICS (mean BDP equivalent dose of inhaled corticosteroid 2224.68microg/die) in association with long-acting beta(2) agonists. Our aim was to describe the experience, efficacy and safety in a cohort of Italian patients treated with omalizumab in a real-life clinical setting. One hundred and forty two patients from 13 Italian Centers were observed and analysed. The dosage of omalizumab was established according to the labelling indication, with a median dose of IgE of 297.38IU/ml or kU/l. During the previous year, all patients experienced frequent exacerbations (mean=4.87), emergency visits (mean=4.45) and hospitalisation (mean=1.53). Following treatment with omalizumab, the annual rate of exacerbations, emergency visits and hospitalisation decreased by 79%, 88% and 95%, respectively. The proportion of patients without exacerbation, not needing emergency visits and hospitalization increased by 610%, 154% and 28%, respectively. The response to omalizumab measured with the GETE (global evaluation of treatment effectiveness) scale rated as good to excellent in 77% of patients. Overall, 9.6% (n=9) of the patients experienced one single adverse effect. Only one patient reported a serious adverse event (local reaction at the site of injection) leading to interruption of treatment. The observed reduction of asthma-related events in particularly poorly controlled patients in this Italian real-life setting is consistent with the results of other observational studies.

Airborne Cupressaceae pollen in southern Italy.

The allergenic airborne pollen of Cupressaceae was surveyed in the area of Bari (Southern Italy) over an 8-year period (1982-1989). A Burkard 7-day recording volumetric spore trap was used for the aerobiologic investigation. The results showed a notable annual pollinic presence of airborne Cupressaceae pollen, the largest amount recorded in winter and early spring. Remarkable fluctuations of the Cupressaceae pollen counts in a 2-year cycle were also observed. The features of the main pollen season are described. In particular, its duration was found to be on average 45 days. A study of Cupressaceae trees distribution indicated that the most widespread genus was Cupressus, represented in particular by the species Cupressus arizonica Green and Cupressus Sempervirens L. The employment of these trees for reforestation and garden-use has increased considerably in the last 40 years. These findings can also be of interest in other countries where Cupressaceae allergy has been reported, particularly in the Mediterranean basin and in North America.

Changes in skin reactivity, specific IgE and IgG levels after one year of immunotherapy in olive pollinosis.

Changes in specific skin reactivity, specific IgE and specific IgG after immunotherapy (IT) were investigated in olive pollinosis. Thirty patients, receiving IT with commercial extracts, were studied in comparison with a control group of seven patients, receiving only drug therapy. Skin reactivity, IgE and IgG were assessed before starting IT and 1 year later. Definite changes in the three considered parameters occurred in patients given IT with Olea europaea extracts; no variation was observed in the control group. The specific skin reactivity, evaluated by means of quantitative skin prick tests, significantly decreased (Skin Index geometrical mean from 2.73 to 0.88, P less than 0.001); the specific IgE, measured by RAST, were surprisingly decreased (from 7.76 to 4.74 PRU/ml, P less than 0.001); the specific IgG, measured by ELISA, in basic conditions were detectable only in nine patients of 30, while, after IT, they were found in almost all patients with a remarkable increase (from 5.48 to 266.89 AU/ml, P less than 0.001). No correlation was found among the changes in the considered parameters, suggesting that, at least in olive pollinosis, specific skin reactivity, specific IgE and specific IgG are three variables depending on IT but reciprocally independent.

Second generation antihistamines in the treatment of seasonal allergic rhinitis due to Parietaria and cypress pollen.

Second generation antihistamines have been employed in the treatment of seasonal allergic rhinitis for many years. However, their effects on two distinctive Mediterranean allergic conditions, viz. Parietaria pollinosis and cypress pollinosis, have been scarcely investigated, so far. A comparative efficacy and side effect trial of astemizole and terfenadine in the treatment of seasonal allergic rhinitis due to either Parietaria or cypress pollen was carried out in 27 adult patients, according to a double-blind, double-dummy parallel-group design. Airborne pollen monitoring allowed comparison of symptom scores with pollen counts. Seven patients (26%) withdrew, due to poor symptom control. In contrast, in a subset of 15 patients who completed the trial, treatment led to a substantial and statistically significant decline in symptom severity in both the astemizole and the terfenadine study group. However, no statistically significant inter-group differences could be detected.

Allergens of Arizona cypress (Cupressus arizonica) pollen: characterization of the pollen extract and identification of the allergenic components.

Species of the Cupressaceae family are an important cause of respiratory allergies in countries with a Mediterranean climate. An allergenic extract from Cupressus arizonica pollen was prepared with two extraction steps followed by ammonium sulfate precipitation, giving a protein yield of about 3%. Cupressus arizonica pollen extract was also characterized by means of sodium dodecylsulfate-polyacrylamide gel electrophoresis, followed by IgE and IgG immunoblotting and lectin blotting. IgE reactivity was restricted to six components, whereas IgG binding showed a more complex pattern. A 43 kd component, predominant both in its intensity and frequency of recognition by human IgE antibodies, was identified as the major allergen of C. arizonica. Four of the six IgE-binding components, including the major allergen, seem to be glycoproteins, as confirmed by the lectin blotting analysis. The extract produced inhouse was used to set up an immunoenzymatic test to evaluate the specific IgE binding in a panel of sera from 33 immunotherapy-free subjects who were monosensitized to cypress pollen. The percent of positivity obtained was much higher than that reported in the literature for commercial immunoassays.

Purification and fine characterization of a major allergen from Olea europaea pollen extract.

Olea europaea (olive) pollen extract was prepared by aqueous extraction and characterized by biochemical and immunochemical methods. Two components, displaying respective mol. wt. of 17,000 and 19,000, were the most reactive allergens, being the doublet (designated Ole e I) recognized by most sera tested. The 19,000 mol. wt. component, purified by conventional biochemical procedure and lectin-affinity chromatography from the Ole e I doublet, was deglycosylated and analyzed by SDS-PAGE and by ELISA inhibition. The results obtained suggest that the 19,000 mol. wt. component represents the glycosylated form of the 17,000 component.

Fusaproliferin production by Fusarium subglutinans and its toxicity to Artemia salina, SF-9 insect cells, and IARC/LCL 171 human B lymphocytes.

Fusarium subglutinans is an important pathogen of maize and other commodities worldwide. We examined MRC-115 and 71 other F. subglutinans strains from various geographic areas for their ability to synthesize fusaproliferin, a novel toxic sesterterpene recently isolated from F. proliferatum. Fusaproliferin production ranged from 30 to 1,500 micrograms/g of dried ground substrate, with 33 strains producing more than 500 micrograms/g. In particular, strain MRC-115 produced as much as 1,100 to 1,300 micrograms/g. In toxicity studies of two invertebrate models, fusaproliferin was toxic to Artemia salina (50% lethal dose, 53.4 microM) and to the lepidopteran cell line SF-9 (50% cytotoxic concentration, approximately 70 microM, after a 48-h exposure). Fusaproliferin was also toxic to the human nonneoplastic B-lymphocyte cell line IARC/LCL 171 (50% cytotoxic concentration, approximately 55 microM in culture in stationary phase after a 48-h exposure). Experiments performed will cells exposed at seeding suggested a possible cytostatic effect at subtoxic concentrations.

5-Lipoxygenase upregulation by dexamethasone in human mast cells.

In spite of intensive research, our understanding of the regulation of expression of 5-LO (the key enzyme in the leukotriene metabolism) remains fragmentary. We investigated the effects of dexamethasone on the expression of this gene in a binary model consisting of two clones of the human mast cell line HMC-1, one with a 5-LO-negative and the other with a 5-LO-positive phenotype, respectively. When dexamethasone was included in the culture medium at a physiologically relevant concentration, biosynthesis of 5-LO derivatives increased considerably not only in the 5-LO-negative HMC-1 cells (approx 10-fold) but also in the 5-LO-positive cells, characterized by an already substantial enzyme activity. Consistently, Northern blot analysis revealed that a dramatic increase in the abundance of 5-LO mRNA occurred when the cells were exposed to dexamethasone. Likewise, a significant increase in the immunoreactive 5-LO protein was detected by Western blotting. In contrast, dexamethasone seemed to have no effect on the expression of two other genes of pivotal importance in leukotriene biosynthesis, viz. FLAP and LTC(4) synthase. We conclude that in human mast cells glucocorticoids effectively and selectively upregulate the expression of 5-LO.

Expression of prostaglandin endoperoxide H synthase 1 and 2 in human placenta at term.

Prostaglandins play an important role in reproduction, particularly in pregnancy and parturition. We investigated the expression of prostaglandin endoperoxide H synthase (PGHS) 1 and 2, key enzymes in prostaglandin biosynthesis, in the human placenta at term. Northern blot analysis of placenta total and poly(A)+ RNA failed to detect significant levels of PGHS-1 mRNA, using a human PGHS-1 specific DNA probe. In contrast, definite PGHS-2 mRNA bands, with a calculated size of about 4.5 kb, were observed in Northern blots of placenta poly(A)+ RNA, using a PGHS-2 specific DNA probe. Moreover, PGHS-1 and PGHS-2 expression was assessed at the translational level by Western blot analysis. Thus, using three highly specific antibodies, we found a selective expression of PGHS-2 immunoreactive protein. These results indicate that PGHS-2 is the PGHS isoform prevalently expressed in the human placenta at term and support the hypothesis that PGHS-2 plays a prominent role in the maintenance of pregnancy, in line with the proposed anti-apoptotic and growth promoting properties of this enzyme.