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Notizen: Background: It has been reported for the peripheral T cell repertoire that CD4 molecules may enhance adhesion between T cells and antigen presenting cells and, through their physical association with T cell antigen receptors, contribute to signal transduction.Objective: The aims of this study were to determine if the modulation of CD4 molecules had differential effects on T cell recognition, antigen induced cytokine (IL-4 and IFNγ), release and the induction of specific anergy for human TH-0, TH-1 and TH-2 cells.Methods: A panel of anti-CD4 antibodies was examined for its ability to modulate T cell proliferation, cytokine production and tolerance induction in house dust mite (TH-0 and TH-2) and influenza haemagglutinin (TH-1) specific human CD4+ T cell clones all restricted by DRB1*1101 and isolated from dust mite allergic individuals.Results: We observed that anti-CD4 antibodies may inhibit or enhance antigen mediated T cell proliferation, which may reflect the differential requirements of T cells for selective functions of CD4. Furthermore, IFNγ and IL-4 production was differentially modulated depending on the specificity of the anti-CD4 antibody and the clone of T cells. However, pretreatment of T cells with anti-CD4 antibody alone neither induced nor enhanced the susceptibility of T cells to peptide mediated anergy.Conclusion: Antigen recognition by different subsets of human CD4+ T cells has differential requirements on CD4, whereas the induction of specific anergy appeared to be independent of the functions of CD4 molecules. Antigen induced IFNγ production was more susceptible than IL-4 to the inhibitory effects of anti-CD4 antibodies. Furthermore, it appeared that certain anti-CD4 antibodies can dissociate antigen induced IFNγ and IL-4 production, and may downregulate IFNγ synthesis without inhibiting antigen dependent proliferation.

Notizen: Background Several fungal species are known to cause severe respiratory and cutaneous allergic diseases. Extracts from several allergenic fungi are used for in vivo and in vitro tests, as standard preparations are still not available.Objective The aims are to define the pattern of in vivo and in vitro IgE reactivity to fungal species in an allergic population with respiratory symptoms; to determine the influence of different extract preparations on diagnostic results; and to evaluate whether there exists a relationship between the diagnostic pattern of reactivity and the pattern of specific IgE reactivity in immunoblots.Methods Skin prick tests were applied to a cohort of 4962 respiratory subjects, aged 3–80 years. Fungal extracts from Alternaria, Aspergillus, Candida, Cladosporium, Penicillium, Saccharomyces, and Trichophyton were used, along with extracts from pollens, mites, and animal dander. Demographical and diagnostic data were recorded. IgE detection was carried out with the same allergenic extracts plus Malassezia. Comparative skin tests and IgE detection were carried out using extracts from three commercial suppliers. IgE immunoblots were carried out with the same panel of commercial fungal extracts and were compared with in-house extracts. Data analysis was carried out by grouping the population on the basis of their reactivity to a single, to two or to more than two, mould species.Results Nineteen percent of the allergic population reacted to at least one fungal extract by means of the skin test. Alternaria and Candida accounted for the largest number of positive tests, and along with Trichophyton they were the main sensitizers in the subset of patients with an isolated sensitization. The prevalence of skin test reactivity increased for these three fungi in the subsets with two associated reactivities and, furthermore, in the subset showing reactivity to more than two mould species. In the latter group, a steady increase of the skin test reactivity was recorded for all the other fungal sources, suggesting a clustered reactivity. Comparative skin and IgE testing with different groups of subjects with a simple pattern of skin reactivity resulted in sensitivity differences between in vivo and in vitro tests, whereas discrepant results were recorded in the subsets of patients with multiple fungi sensitization. Although hampered by the limited reliability of fungal extracts, IgE immunoblots revealed differing patterns of reactivity when sera from the three subsets were used. This suggests a link between the diagnostic reactivity pattern and the IgE sensitization to extracts' components. Age and gender distribution differed among the Alternaria-, Candida-, and Trichophyton-sensitized subjects, but not in the subset with more than two fungi sensitizations.Conclusions The preliminary assessment of a new classification of the mould-sensitized population has been reached. The limiting quality of fungal extracts requires future studies using an allergenic molecule-based approach. The diagnostic process and the definition of the reactivity pattern would thus be easy, and it could lead to a novel specific immunotherapy approach.

Notizen: Aims:  Adenocarcinomas of the distal oesophagus and especially the oesophago–gastric junction have shown an increasing incidence during the last decade. Definition of subgroups according to different sites of development, histogenesis or aetiology may prove to be valuable for clinical diagnosis and treatment. Previous studies have shown differences in cytokeratin patterns between Barrett's metaplasia of the oesophagus and intestinal metaplasia in the stomach. The aim of our study was to investigate whether the expression of certain cytokeratins (CK7, CK20) and mucins (MUC1, MUC2, MUC5AC) exhibit clear-cut patterns, thus allowing a subclassification of adenocarcinomas of the oesophago–gastric junction. The possibility of a relationship between antigen expression and the presence or absence of Barrett's metaplastic epithelium was also studied.Methods and results:  CK7, CK20, MUC1, MUC2 and MUC5AC were visualized in six adenocarcinomas of the distal oesophagus, 29 adenocarcinomas of the oesophago–gastric junction and eight adenocarcinomas of the proximal stomach. CK7, CK20 and MUC1 were strongly expressed in the great majority of all neoplasms under study, whereas MUC2 and MUC5AC were absent or only faintly detectable. CK20 exhibited a significantly stronger expression in poorly differentiated tumours (G3) and MUC1 immunoreactivity correlated with tubular and papillary versus signet-ring cell histopathology. Other statistically significant correlations between antigens and histopathological features (pTNM stage, grading, histopathological subtype, presence/absence of Barrett's epithelium) were not observed.Conclusions:  According to our results, most adenocarcinomas of the oesophago–gastric junction show a CK7+, CK20+, MUC1+ phenotype irrespective of the presence or absence of Barrett's epithelium. The immunohistochemical data suggest a similar histogenesis of these tumours.

Notizen: Comparative evaluation of the prognostic value of MUC1, MUC2, sialyl-Lewisa and sialyl-Lewisx antigens in colorectal adenocarcinoma Aims: The significance of MUC1, MUC2 and sialylated Lewis blood group antigens as prognostic markers in colorectal adenocarcinoma was investigated in a large series of patients because previous investigations revealed inconsistent results due to unrelated tumour samples from different patient groups and methodological differences. Methods and results: Tissues from 243 patients with colorectal adenocarcinoma were stained immunohistochemically. MUC1 showed a strong immunoreactivity (in more than 35% of the tumour area) in 32.5%, MUC2 in 51.0%, sialyl-Lewisx in 67.9% and sialyl-Lewisa in 73.7% of the cases, respectively. MUC1 immunoreactivity displayed a significant correlation with tumour progression as reflected by advancing pTNM staging and poor differentiation. MUC2 expression was significantly stronger in mucinous adenocarcinomas. Sialyl-Lewisx immunostaining correlated with the extent of lymph node metastasis as well as low cytological differentiation. According to univariate and multivariate analysis (P 〈 0.0001) only MUC1 reactivity represented a marker of worse survival probability, opposed to the sialylated Lewis antigens that did not exert a predictive value. Conclusions: According to our data, MUC1 and sialyl-Lewisx immunoreactivity exhibit statistically significant correlations with established markers of tumour progression. However, only MUC1 presents as an independent prognostic factor of colorectal adenocarcinoma.

Notizen: Expression of MMP-2 is associated with progression and lymph node metastasis of gastric carcinoma Aims: One important step in tumour invasion is the penetration of the basement membrane. Matrix metalloproteinases (MMPs) play a key role in the migration of normal and malignant cells through the basement membrane. The aim of this study was to investigate correlations between matrix metalloproteinase 2 (MMP-2) immunoreactivity and currently used classification systems and possible relationships between lymph node metastasis and MMP-2 expression. Methods and results: This prospective study analysed specimens obtained from 114 gastric cancer patients (mean age 64 years; range 33–86 years) who underwent gastrectomy with extended lymphadenectomy. All specimens were categorized according to UICC classification, WHO classification, tumour differentiation, Laurén classification, Ming classification and Goseki classification. Formalin-fixed paraffin-embedded tumour specimens were stained using an avidin–biotin complex peroxidase assay. MMP-2 expression in the tumour epithelium was studied by immunohistochemistry with semiquantitative (score 0–3) evaluation. The MMP-2 staining pattern was positive (score 1–3) in 93 (81.6%) specimens and negative (score 0) in 21 (18.4%) samples. No significant correlations were found between MMP-2 expression and other variables such as age, tumour differentiation, WHO, Lauren, Goseki, and Ming classifications. In contrast, the intensity of MMP-2 staining in tumour cells correlated significantly with depth of tumour infiltration (T-stage), lymph node metastasis (N-stage), distant metastasis (M-stage), and UICC stage. Conclusions: Expression of MMP-2 is strongly associated with tumour progression and lymph node metastasis in gastric cancer. Therefore MMP-2 staining may be clinically useful as predictor of tumour progression, especially for lymph node metastasis.