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The presence of specific IgE antibodies to invertebrates is common among patients with rhinitis and asthma. Tropomyosin has been described as an invertebrate cross-reactive allergen. We have recently characterized an allergenic extract from silverfish (Lepisma saccharina). Since this insect could be a new source of tropomyosin in the indoor environment, we have thought important to clone and characterize the tropomyosin from it.Recombinant tropomyosin was cloned and characterized by means of immunoblotting withtropomyosin-specific monoclonal antibodies, rabbit polyclonal antibodies and IgE from allergic patients. Its allergenic activity was investigated in histamine release assays. Immunoblotting and ELISA inhibition were carried out to identify the natural tropomyosin in the silverfish extract and to study the cross-reactivity among other arthropod tropomyosins.Tropomyosin-specific antibodies recognized in immunoblotting the natural tropomyosin in the insoluble fraction of silverfish extract. The silverfish tropomyosin (Lep s 1) was cloned and fully expressed. It shared high homology with other arthropod tropomyosins. rLep s 1 was recognized by tropomyosin-specific monoclonal and polyclonal antibodies and by IgE of allergic patients. It was able to inhibit the IgE binding to the insoluble fraction of silverfish extract, and to induce histamine release by an arthropod-allergic serum. Inhibition experiments revealed IgE cross-reactivity between rLep s 1 and other arthropod tropomyosins.rLep s 1 is the first allergen cloned and characterized from silverfish extract. It enabled us to identify the natural counterpart in the insoluble fraction of silverfish extract, suggesting that the tropomyosin is not readily extractable with a classic aqueous extraction procedure. rLep s 1 displayed biological activity, suggesting that it could be regarded as a useful tool to study the role of silverfish tropomyosin in the sensitization to invertebrate allergic sources. [ABSTRACT FROM AUTHOR]

We have carried out a retrospective review of 61 patients with Mallory-Weiss syndrome, 9 of whom underwent hemostatic injection treatment. At emergency endoscopy, 3 patients (5%) were actively bleeding and 6 (10%) had stigmata of recent hemorrhage. Fifty-two patients had a lesion of the cardia which was the suspected source of bleeding in 33 cases (54%). In the remaining 19 cases (31%) this site was not considered responsible because other sites of bleeding were present in the upper gastrointestinal tract. The 9 patients with active bleeding or stigmata of recent hemorrhage underwent injection treatment and the other 52 patients were treated with H2 antagonists. The low rebleed rate and the zero mortality recorded in this series indicate that endoscopy is the optimum method for diagnosis and treatment of patients with Mallory-Weiss syndrome. [ABSTRACT FROM AUTHOR]

IgG antibody response to the inhalant allergen Parietaria judaica (Pj) and IgG subclass distribution were studied in 82 normal subjects, divided into three groups according to age (0-1, 1-20, and 20-60 years) and in 32 allergic subjects aged 20-60 years. Both normal and allergic subjects showed an IgG response, and all had IgG 1 antibodies specific for PjE. Serum IgG2, IgG3, and IgG4 against PjE were detectable in 36%, 46%, and 22% of normal subjects, and in 58%, 31%, and 65% of allergic subjects, respectively. A significant difference in class distribution between allergic and age-matched normal subjects was found only for IgG4 antibodies against PjE (65% and 17%; P < 0.01). The ELISA results were also analyzed quantitatively, taking into account the relative proportion of specific antibodies. Thus, in normal subjects IgG 1 antibodies showed a decreasing trend as the age rose, while no differences according to the age of the subject were found for IgG2 and IgG4. When data from allergic subjects (20-60 years) and the age-matched normal group were compared, they were different for the relative percentage of IgG2 only, showing for this a significantly lower value (P < 0.001). The present data indicate that normal and allergic subjects show differences in the IgG iso type distribution depending on their sensitivity and duration of allergen exposure. [ABSTRACT FROM AUTHOR]

Olea europaea (olive) pollen extract was prepared by aqueous extraction and characterized by biochemical and immunochemical methods. Two components, displaying respective mol. wt. of 17000 and 19000, were the most reactive allergens, being the doublet (designated Ole e I) recognized by most sera tested. The 19000 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 19000 mol. wt. component represents the glycosylated form of the 17000 component. [ABSTRACT FROM AUTHOR]

The in vitro proliferative response to separated immunologically relevant components of Parietaria Judaica pollen extract (PjE) was investigated by proliferation assay and limiting dilution analysis, in peripheral blood mononuclear cells from Parietaria-allergic subjects and non allergic controls. In the same subjects, the profile of the antibody response to the PjE fractions was also studied by immunoblotting to evaluate the functional significance of allergen-induced T-cell activation in the two groups. The estimated frequency of PjE-reactive T cells in peripheral-blood mononuclear cells was low in both groups. No difference was found between the Parietaria-allergic subjects and nonallergic controls. To assess the overall contribution to the cellular response of PjE components of different molecular weights, we separated the extract by the SDS--PAGE technique, and the fractions were blotted onto nitrocellulose and solubiized. Almost all the 14 fractions tested induced T-cell proliferation, at different degrees of magnitude. Responses were similar in the allergic subjects and nonallergic controls. Immunoblotting demonstrated specific IgG antibodies to the 14 PjE fractions not only in the allergic subjects, but also in the healthy controls, whereas IgE antibodies were found, as expected, only in the sera from atopic subjects. These findings indicate that PjE fractions elicit similar T-cell activation and IgG production in allergic and normal subjects. [ABSTRACT FROM AUTHOR]

Cross-reactivity between the different components in Parietaria judaica pollen extract has been investigated by polyclonal as well as monoclonal antibodies before, and after chemical deglycosylation obtained by trifluoromethanesulphonic acid (TFMS) treatment of the extract. In western blotting a polyclonal rabbit antiserum, obtained by injecting purified Par j I, was able to recognise many components of the native extract. However, its reactivity was restricted, after chemical deglycosylation of the extract, to the major allergen alone, indicating that its cross-reactivity was due to sugar moieties. Moreover, out of several monoclonal antibodies raised by injecting the whole Parietaria judaica extract, one (1A4/2F8) was also able in western blotting to recognise an epitope shared by many components of the extract except the major allergen Par j I. However, in this case the broad reactivity of the antibody was not affected by the deglycosylating procedure. When the reactivity of Parietaria judaica extract was tested before and after sugar removal, against specific IgE from a pool of patient sera, no differences could be demonstrated, thus indicating that carbohydrates are not strongly involved in the binding of Parietaria judaica-specific IgE. The results indicate that both proteic and carbohydratic cross-reactive epitopes are shared by many components of Parietaria judaica pollen extract. [ABSTRACT FROM AUTHOR]

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 < 0.001); the specific IgE, measured by RAST, were surprisingly decreased (from 7.76 to 4.74 PRU/ml, P < 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 < 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. [ABSTRACT FROM AUTHOR]

We investigated the in vitro proliferation of peripheral blood mononuclear cells (PBMC) from Parietaria-allergic subjects, atopic patients with other sensitizations and healthy controls to Parietaria judaica pollen extracts. PBMC from almost all 44 subjects, divided into five groups (Parietaria-, grass-, Parietaria and grass-, Dermalophagoides-sensitive patients and normal individuals) were able to proliferate in response to the extract without statistically significant differences between groups. Mean values of the stimulation indexes for the five groups were respectively: 10.73, 3.18, 5.50, 10,56, 9.28. The results of separation experiments showed that the responding cells were T lymphocytes. Mitogenic effect of the Parietaria pollen extract was excluded by the absence of proliferative PBMC response from cord blood of seven newborns. These results indicate that Parietaria- sensitive, other atopies and normal individuals have Parietaria-specific T cells able to proliferate in vitro to Parietaria allergens. [ABSTRACT FROM AUTHOR]