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Background: Coeliac disease is a small intestine enteropathy caused by permanent intolerance to wheat gluten. Gluten intake by patients with coeliac disease provokes a strong reaction by intestinal intraepithelial lymphocytes (IELs), which normalises on a gluten-free diet. Aim: To investigate whether impaired extrathymic T cell maturation and/or secondary T cell receptor (TCR) gene recombination in IELs are features of coeliac disease which could contribute to the failure of establishing tolerance to gluten. Methods: Expression levels of the four splice-forms of recombination activating gene-1 (RAG1) mRNA and preT α-chain (preTα) mRNA were determined in IEL-subsets of children with coeliac disease and controls. Frequencies of RAG1 expressing IELs were determined by immunomorphometry. Results: In controls, the RAG1-1A/2 splice-form selectively expressed outside the thymus, was dominant and expressed in both mature (TCR+) and immature (CD2+CD7+TCR2) IELs (~8 mRNA copies/18S rRNA U). PreTα was expressed almost exclusively in CD2+CD7+TCR2 IELs (~40 mRNA copies/18S rRNA U). By contrast, RAG1 and preTα mRNA levels were low in patients with coeliac disease compared to controls, both with active disease and with inactive, symptom-free disease on a gluten-free diet (p values <0.01 for mature and <0.05 for immature IELs). Similarly, the frequencies of RAG1+ IELs were significantly lower in patients with coeliac disease compared to controls (p<0.001). Conclusions: Patients with coeliac disease appear to have an impaired capacity for extrathymic TCR gene rearrangement. This is an inherent feature, which probably plays a pivotal role in the failure to efficiently down-regulate the T cell response to gluten. [ABSTRACT FROM AUTHOR]

Renal cell carcinoma (RCC) is the most prevalent cancer of the kidney. In human RCC cells, we recently showed that insulin-like growth factor I (IGF-I) has growth-promoting effects regulated by IGF-binding protein 3 (IGFBP-3). In this study, the analysis was expanded to include the interaction between the IGF and transforming growth factor-β (TGF-β) systems in the human RCC cells Caki-2 (from a primary tumor) and SK-RC-52 (from a metastasis). Functional effects such as cell proliferation, TGF-β receptor (TβR) signaling, and IGFBP-3 levels were monitored after stimulation with various concentrations of IGF-I, TGF-β, and IGFBP-3. In addition, human RCC tissues as well as experimental human RCC tumors were analyzed for cellular expression of phosphorylated Smad2 by immunohistochemistry. TGF-β regulated the endogenous IGFBP-3 levels in these RCC cells as neutralizing anti-TGF-β(1–3) antibodies strongly reduced the basal IGFBP-3 level. In addition, IGF-I increased the IGFBP-3 levels five- to eightfold with TGF-β acting in synergy to enhance the IGFBP-3 levels 12- to 17-fold. Neutralizing TGF-β(1–3) activity circumvented the growth inhibitory effects of IGFBP-3 seen in SK-RC-52, whereas it inhibited the growth-promoting effects of IGFBP-3 in Caki-2. Moreover, IGF-I interacted directly with TGF-β activation of the TβR complex by enhancing phosphorylation and nuclear translocation of Smad2. This study demonstrates a direct interaction of the IGF and TGF-β systems in human renal carcinoma cells. The observations that IGF-I enhances the TGF-β signaling and that TGF-β promotes IGFBP-3 production and thus influence the biological activity of IGF may be of importance for future therapeutic options.Kidney International (2006) 70, 1584–1590. doi:10.1038/sj.ki.5001805; published online 13 September 2006 [ABSTRACT FROM AUTHOR]

The accuracy of 18S rRNA, β-actin mRNA and glyceraldehyde-3-phosphate dehydrogenase (GAPDH) mRNA as indicators of cell number when used for normalization in gene expression analysis of T lymphocytes at different activation stages was investigated. Quantitative real-time reverse transcriptase-polymerase chain reaction was used to determine the expression level of 18S rRNA, β-actin mRNA, GAPDH mRNA and mRNA for six cytokines in carefully counted samples of resting human peripheral blood mononuclear cells (PBMCs), intestinal lymphocytes and PBMCs subjected to polyclonal T-cell activation. The 18S rRNA level in activated and resting PBMCs and intestinal lymphocytes was essentially the same, while the levels of β-actin and GAPDH mRNAs fluctuated markedly upon activation. When isolated γδTCR+, CD4+ and CD8+ subpopulations were studied, 18S rRNA levels remained unchanged after 21 h of activation but increased slightly after 96 h. In contrast, there was a 30–70-fold increase of GAPDH mRNA/cell in these cell populations upon activation. Cytokine analysis revealed that only normalization to 18S rRNA gave a result that satisfactorily reflected their mRNA expression levels per cell. In conclusion, 18S rRNA was the most stable housekeeping gene and hence superior for normalization in comparative analyses of mRNA expression levels in human T lymphocytes. [ABSTRACT FROM AUTHOR]

Superantigens (SAGs) cause a massive T-cell proliferation by simultaneously binding to major histocompatibility complex (MHC) class II on antigen-presenting cells and T-cell receptors (TCRs) on T cells. These T-cell mitogens can cause disease in host, such as food poisoning or toxic shock. The best characterized groups of SAGs are the bacterial SAGs secreted by Staphylococcus aureus and Streptococcus pyogenes. Despite a common overall three-dimensional fold of these SAGs, they have been shown to bind to MHC class II in different ways. Recently, it has also been shown that SAGs have individual preferences in their binding to the TCRs. They can interact with various regions of the variable β-chain of TCRs and at least one SAG seems to bind to the α-chain of TCRs. In this review, different subclasses of SAGs are classified based upon their binding mode to MHC class II, and models of trimolecular complexes of MHC–SAG–TCR molecules are described in order to reveal and understand the complexity of SAG-mediated T-cell activation. [ABSTRACT FROM AUTHOR]

Superantigens activate T-cells by linking the T-cell receptor to MHC class II on antigen-presenting cells, and novel reactivity can be introduced by fusing the superantigen to a targeting molecule. Thus, an antibody-targeted superantigen, which activates T cells to destroy tumour cells, might be used as cancer therapy. A suitable target is the 5T4 oncofetal antigen, which is expressed on many carcinomas. We constructed a fusion protein from a Fab of a monoclonal antibody recognizing the 5T4 antigen, and an engineered superantigen. The recombinant product 5T4FabV13-SEA[SUBD227A] bound the 5T4 antigen expressed on the human non-small-cell lung cancer cell line Calu-1 with a K[SUBd] (of 1.2 nM while the substitution of Asp227 to Ala in the superantigen moiety reduced binding activity to MHC class II. 5T4FabV13-SEA[SUBD227A] tumour reactivity was demonstrated in 7/7 NSCLC samples by immunohistochemistry, while normal tissue reactivity was low to moderate. 5T4FabV13-SEA[SUBD227A] induced significant T-cell-dependent in vitro killing of sensitive 5T4 bearing Calu-1 cells, with maximum lysis at 10[SUP-10] M, while the capacity to lyse MHC class II expressing cells was approximately 1000 times less effective. Immunotherapy of 5T4FabV13-SEA[SUBD227A] against human NSCLC was investigated in SCID mice reconstituted with human peripheral blood mononuclear cells. Mice carrying intreperitoneally growing Calu-1 cells showed significant reduction in tumour mass and number after intravenous therapy with 5T4FabV13-SEA[SUBD227A]. Thus, 5T4FabV13-SEA[SUBD227A] has highly attractive properties for therapy of human NSCLC. [ABSTRACT FROM AUTHOR]

Discusses the degree of `women-friendliness' in Sweden. Focus on gender structure of labor market; Analysis of integration and segregation processes; Concentration of different labor-market situations; Analysis of the implementation of gendering in the gender contract labor market.

A response by U. Bergman and colleagues to a letter to the editor regarding their study on severe acne, occurrence of suicide attempts, and treatment with isotretinoin in the 2010 issue is presented.

To assess the risk for suicide attempt before, during and after treatment with isotretinoin for severe acne. Retrospective cohort-study linking a named patient register of isotretinoin-users 1980–1989 to the hospital discharge- and cause of death registers 1980–2001. 5,756 patients prescribed isotretinoin for severe acne observed for 17,192 person-years before, 2,905 on and 87,120 after treatment. Main outcome measures Standardized Incidence Ratio (SIR): observed divided by expected number of suicide attempts standardized by sex, age and calendar-year, calculated up to three years before, during and up to 15 years after end of treatment. 128 patients were hospitalized for suicide attempt. During the year preceding treatment, the SIR for suicide attempt was elevated: 1.57 (95% CI 0.86 to 2.63) for all (including repeat) attempts, and 1.36 (95% CI 0.65 to 2.50) counting only first attempts. For all and first attempts, SIRs during and up to 6 months after treatment was 1.78 (1.04 to 2.85) and 1.93 (1.08 to 3.18) respectively. The observed number of attempts was close to the expected during the 15 years of follow-up. The number needed to harm was 2,300 new 6-months’ treatments per year, for one additional first suicide attempt to occur. An increased risk for suicide attempt was observed up to six months after treatment with isotretionoin, which motivates a close monitoring of patients regarding suicidal behaviour for up to a year after treatment has ended. The risk for suicide attempts were rising already before treatment, and therefore, an additional risk due to the isotretinoin treatment cannot be established. [ABSTRACT FROM AUTHOR]

Human muscle is studied during glycogen depletion and repletion to understand the influence of exercise and muscle glycogen on total ceramide content. In addition, fiber-type-specific ceramide storage is investigated. Ten healthy males (26.4 +/- 0.9 years, BMI 24.4 +/- 0.7 kg m(-2) and VO2max 57 +/- 2 mL O2 min(-1) kg(-1)) participated in the study. On the first day, one leg was glycogen-depleted (DL) by exhaustive intermittent exercise followed by low carbohydrate diet. Next day, in the overnight fasted condition, muscle biopsies were excised from vastus lateralis before and after exhaustive exercise from both DL and control leg (CL). Muscle glycogen was analyzed biochemically and total muscle ceramide content by 2D quantitative lipidomic approach. Furthermore, fiber-type ceramide content was determined by fluorescence immunohistochemistry. Basal muscle glycogen was decreased (P < 0.05) with 50 +/- 6% in DL versus CL. After exhaustive exercise, muscle glycogen was similar in CL and DL 139 +/- 38 and 110 +/- 31 mmol kg(-1), respectively. Total muscle ceramide 58 +/- 1 pmol mg(-1) was not influenced by glycogen or exercise. Ceramide content was consistently higher (P < 0.001) in type I than in type II muscle fibers. In conclusion, human skeletal muscle, ceramide content is higher in type I than in type II. Despite rather large changes in muscle glycogen induced by prior depletion, exercise to exhaustion and repletion, total muscle ceramide concentration remained unchanged. [ABSTRACT FROM AUTHOR]

Grönros J, Wikström J, Brandt-Eliasson U, Forsberg GB, Behrendt M, Hansson GI, Gan LM. Effects of msuvastatin on cardiovascular morphology and function in an ApoE-knockout mouse model of athemsclerosis. Am JPhysiol Heart Circ Physiol 295: H2046-H2053, 2008. First published September 12,2008; doi:10.1152/ajpheart.00I33.2008.-This study investigated the effects of rosuvastatin on plaque progression and in vivo coronary artery function in apolipoprotein E-knockout (ApoE-KO) mice, using noninvasive high-resolution ultrasound techniques. Eightweek-old male ApoE-KO mice (n = 20) were fed a high-fat diet with or without rosuvastatin (10 μmol∙kg[sup-1∙ day[sup-1]) for 16 wk. When compared with control, rosuvastatin reduced total cholesterol levels (P < 0.05) and caused significant retardation of lesion progression in the brachiocephalic artery, as visualized in vivo using an ultrasound biomicroscope (P < 0.05). Histological analysis confirmed the reduction of brachiocephalic atherosclerosis and also revealed an increase in collagen content in the statin-treated group (P < 0.05). Coronary volumetric flow was measured by simultaneous recording of Doppler velocity signals and left coronary artery morphology before and during adenosine infusion. The hyperemic flow in response to adenosine was significantly greater in left coronary artery following 16 wk of rosuvastatin treatment (P < 0.001), whereas the baseline flow was similar in both groups. In conclusion, rosuvastatin reduced brachiocephalic artery atherosclerotic plaques in ApoE-KO mice. Coronary artery function assessed using recently developed in vivo ultrasoundbased protocols, also improved. [ABSTRACT FROM AUTHOR]

In a phase II study, 43 renal cell carcinoma patients were treated with individualised doses of ABR-214936; a fusion of a Fab recognising the antigen 5T4, and Staphylococcal enterotoxin A. Drug was given intravenously on 4 consecutive days, treatment was repeated 1 month later. Treatment was associated with moderate fever and nausea, but well tolerated. Of 40 evaluable patients, 28 had disease control at 2 months, and at 4 months, one patient showed partial response (PR) and 16 patients stable disease. Median survival, with minimum follow-up of 26 months was 19.7 months with 13 patients alive to date. Stratification by the Motzer's prognostic criteria highlights prolonged survival compared to published expectation. Patients receiving higher drug exposure had greater disease control and lived almost twice as long as expected, whereas the low-exposure patients survived as expected. Sustained interleukin-2 (IL-2) production after a repeated injection appears to be a biomarker for clinical effect, as the induced-IL-2 level on the day 2 of treatment correlated with survival. The high degree of disease control and the prolonged survival suggest that this treatment can be effective. These findings will be used in the trial design for the next generation of drug, with reduced antigenicity and toxicity.British Journal of Cancer (2007) 96, 567–574. doi:10.1038/sj.bjc.6603567 www.bjcancer.com Published online 6 February 2007 [ABSTRACT FROM AUTHOR]

Hematogenous spread of tumor cells and metastasis formation in the liver are insidious aspects of cancer progression and are not frequently amenable to curative treatment. We examined the effect of Linomide and antibody-targeted therapy against the formation of hepatic metastases in vivo. For this purpose, syngenic B16 melanoma cells transfected with GA733-2 (a human colon cancer cell surface antigen) were injected into a mesenteric vein of C57/Bl6 mice. To test bacterial superantigen (Sag) targeting for immunotherapy of liver metastases, we used genetically fused proteins consisting of SEA and a Fab moiety of a GA733-2 tumor-reactive antibody (C215Fab-SEA). Linomide dose-dependently reduced hepatic metastases, and at 300 mg/kg this reduction was more than 80%. Treatment with C215Fab-SEA decreased metastases formation by 49% and the combination of Linomide and C215Fab-SEA was found to completely abolish liver metastases (>99% reduction). Taken together, our novel data suggest that Linomide and antibody-targeted superantigen therapy individually markedly reduce and together abolish liver metastases. Considering that current therapy of hepatic metastases is mainly limited to surgical resection in a subgroup of patients, these findings indicate that Linomide alone or in combination with antibody-targeted superantigen may provide a novel approach against liver metastases.Copyright © 2003 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

SUMMARY Ulcerative colitis (UC), a chronic inflammatory bowel disease, exhibits pronounced increase of T lymphocytes in the inflamed mucosa. To understand the role of intestinal T lymphocytes in the pathogenesis of UC their cytokine production in the mucosa was analysed. Intestinal T lymphocytes of UC, Crohn's disease and control patients were analysed for cytokine mRNA levels by real-time quantitative reverse transcription-polymerase chain reaction (RT-PCR) directly after isolation without in vitro stimulation. Frequencies of cytokine positive cells were determined in UC and control colon by immunomorphometry. T lymphocytes in normal colon expressed interleukin (IL)-2, interferon (IFN)-γ , tumour necrosis factor (TNF)-α and transforming growth factor (TGF)-β 1, but not IL-4, IL-5 or IL-10. In UC, a highly significant increase in IL-10 mRNA levels in T lymphocytes and an increased frequency of IL-10 positive cells was seen in colon. IL-10 mRNA levels were also elevated in T lymphocytes of the non-inflamed ileum and correlated with disease activity at both locations. CD4[sup +] T lymphocytes were the major source of IL-10 mRNA. IL-2, IFN-γ and TNF-α mRNA levels were decreased in colonic T lymphocytes, and virtually no IL-2, IFN-γ , TNF-α or TGF-β positive cells were detected in basal lymphoid aggregates. However, scattered IL-10 positive cells were found here. Lamina propria outside the aggregates contained IL-10-, IFN-γ , TNF-α and TGF-β but not IL-2 positive cells. T cells of UC patients did not express IL-4 or IL-5. Taken, together the data suggest a generalized activation of IL-10 producing CD4[sup +] T cells along the intestine of UC patients. The local environment seems to determine the biological consequences of elevated IL-10. [ABSTRACT FROM AUTHOR]