Biomarkers of human gastrointestinal tract regions.

Dysregulation of intestinal epithelial cell performance is associated with an array of pathologies whose onset mechanisms are incompletely understood. While whole-genomics approaches have been valuable for studying the molecular basis of several intestinal diseases, a thorough analysis of gene expression along the healthy gastrointestinal tract is still lacking. The aim of this study was to map gene expression in gastrointestinal regions of healthy human adults and to implement a procedure for microarray data analysis that would allow its use as a reference when screening for pathological deviations. We analyzed the gene expression signature of antrum, duodenum, jejunum, ileum, and transverse colon biopsies using a biostatistical method based on a multivariate and univariate approach to identify region-selective genes. One hundred sixty-six genes were found responsible for distinguishing the five regions considered. Nineteen had never been described in the GI tract, including a semaphorin probably implicated in pathogen invasion and six novel genes. Moreover, by crossing these genes with those retrieved from an existing data set of gene expression in the intestine of ulcerative colitis and Crohn's disease patients, we identified genes that might be biomarkers of Crohn's and/or ulcerative colitis in ileum and/or colon. These include CLCA4 and SLC26A2, both implicated in ion transport. This study furnishes the first map of gene expression along the healthy human gastrointestinal tract. Furthermore, the approach implemented here, and validated by retrieving known gene profiles, allowed the identification of promising new leads in both healthy and disease states.

The shared allelic architecture of adiponectin levels and coronary artery disease.

OBJECTIVE: A large body of epidemiologic data strongly suggests an association between excess adiposity and coronary artery disease (CAD). Low adiponectin levels, a hormone secreted only from adipocytes, have been associated with an increased risk of CAD in observational studies. However, these associations cannot clarify whether this relationship is causal or due to a shared set of causal factors or even confounding. Genome-wide association studies have identified common variants that influence adiponectin levels, providing valuable tools to examine the genetic relationship between adiponectin and CAD. METHODS: Using 145 genome wide significant SNPs for adiponectin from the ADIPOGen consortium (n = 49,891), we tested whether adiponectin-decreasing alleles influenced risk of CAD in the CARDIoGRAM consortium (n = 85,274). RESULTS: In single-SNP analysis, 5 variants among 145 SNPs were associated with increased risk of CAD after correcting for multiple testing (P < 4.4 × 10(-4)). Using a multi-SNP genotypic risk score to test whether adiponectin levels and CAD have a shared genetic etiology, we found that adiponectin-decreasing alleles increased risk of CAD (P = 5.4 × 10(-7)). CONCLUSION: These findings demonstrate that adiponectin levels and CAD have a shared allelic architecture and provide rationale to undertake a Mendelian randomization studies to understand if this relationship is causal.

High-density electric source imaging (esi) in focal epilepsy: a prospective study of 150 operated patients

Purpose: EEG is mandatory in the diagnosis of the epilepsy syndrome. However, its potential as imaging tool is still under estimated. In the present study, we aim to determine the prerequisites of maximal benefit of electric source imaging (ESI) to localize the irritative zone in patients with focal epilepsy. Methods: One hundred fifty patients suffering from focal epilepsy and with minimum 1 year postoperative follow-up were studied prospectively and blinded to the underlying diagnosis. We evaluated the influence of two important factors on sensitivity and specificity of ESI: the number of electrodes (low resolution, LR-ESI: <30 versus high resolution, HR-ESI: 128-256 electrodes), and the use of individual MRI (i-MRI) versus template MRI (t-MRI) as the head model. Findings: ESI had a sensitivity of 85% and a specificity of 87% when HR-ESI with i-MRI was used. Using LR-ESI, sensitivity decreased to 68%, or even 57% when only t-MRI was available. The sensitivity of HR-ESI/i-MRI compared favorably with those of MRI (76%), PET (69%) and ictal/interictal SPECT (64%). Interpretation: This study on a large patient group shows excellent sensitivity and specificity of ESI if 128 EEG channels or more are used for ESI and if the results are coregistered to the patient's individual MRI. Localization precision is as high as or even higher than established brain imagery techniques. HR-ESI appears to be a valuable additional imaging tool, given that larger electrode arrays are easily and rapidly applied with modern EEG equipment and that structural MRI is nearly always available for these patients.

In Vivo Modulation of Mitochondrial Activity Determines HSC Engraftment and Post-Transplant Survival in Mice

Cellular metabolism is emerging as a potential fate determinant in cancer and stem cell biology, constituting a crucial regulator of the hematopoietic stem cell (HSC) pool [1-4]. The extremely low oxygen tension in the HSC microenvironment of the adult bone marrow forces HSCs into a low metabolic profile that is thought to enable their maintenance by protecting them from reactive oxygen species (ROS). Although HSC quiescence has for long been associated with low mitochondrial activity, as testified by the low rhodamine stain that marks primitive HSCs, we hypothesized that mitochondrial activation could be an HSC fate determinant in its own right. We thus set to investigate the implications of pharmacologically modulating mitochondrial activity during bone marrow transplantation, and have found that forcing mitochondrial activation in the post-transplant period dramatically increases survival. Specifically, we examined the mitochondrial content and activation profile of each murine hematopoietic stem and progenitor compartment. Long-term-HSCs (LT-HSC, Lin-cKit+Sca1+ (LKS) CD150+CD34-), short-term-HSCs (ST-HSC, LKS+150+34+), multipotent progenitors (MPPs, LKS+150-) and committed progenitors (PROG, Lin-cKit+Sca1-) display distinct mitochondrial profiles, with both mitochondrial content and activity increasing with differentiation. Indeed, we found that overall function of the hematopoietic progenitor and stem cell compartment can be resolved by mitochondrial activity alone, as illustrated by the fact that low mitochondrial activity LKS cells (TMRM low) can provide efficient long-term engraftment, while high mitochondrial activity LKS cells (TMRM high) cannot engraft in lethally irradiated mice. Moreover, low mitochondrial activity can equally predict efficiency of engraftment within the LT-HSC and ST-HSC compartments, opening the field to a novel method of discriminating a population of transitioning ST-HSCs that retain long-term engraftment capacity. Based on previous experience that a high-fat bone marrow microenvironment depletes short-term hematopoietic progenitors while conserving their long-term counterparts [5], we set to measure HSC mitochondrial activation in high-fat diet fed mice, known to decrease metabolic rate on a per cell basis through excess insulin/IGF-1 production. Congruently, we found lower mitochondrial activation as assessed by flow cytometry and RT-PCR analysis as well as a depletion of the short-term progenitor compartment in high fat versus control chow diet fed mice. We then tested the effects of a mitochondrial activator known to counteract the negative effects of high fat diet. We first analyzed the in vitro effect on HSC cell cycle kinetics, where no significant change in proliferation or division time was found. However, HSCs responded to the mitochondrial activator by increasing asynchrony, a behavior that is thought to directly correlate with asymmetric division [6]. As opposed to high-fat diet fed mice, mice fed with the mitochondrial activator showed an increase in ST-HSCs, while all the other hematopoietic compartments were comparable to mice fed on control diet. Given the dependency on short-term progenitors to rapidly reconstitute hematopoiesis following bone marrow transplantation, we tested the effect of pharmacological mitochondrial activation on the recovery of mice transplanted with a limiting HSC dose. Survival 3 weeks post-transplant was 80% in the treated group compared to 0% in the control group, as predicted by faster recovery of platelet and neutrophil counts. In conclusion, we have found that mitochondrial activation regulates the long-term to short-term HSC transition, unraveling mitochondrial modulation as a valuable drug target for post-transplant therapy. Identification of molecular pathways accountable for the metabolically mediated fate switch is currently ongoing.

Background morbidity in HIV vaccine trial participants from various geographic regions as assessed by unsolicited adverse events.

Background: Recently, more clinical trials are being conducted in Africa and Asia, therefore, background morbidity in the respective populations is of interest. Between 2000 and 2007, the International AIDS Vaccine Initiative sponsored 19 Phase 1 or 2A preventive HIV vaccine trials in the US, Europe, Sub-Saharan Africa and India, enrolling 900 healthy HIV-1 uninfected volunteers.   Objective To assess background morbidity as reflected by unsolicited adverse events (AEs), unrelated to study vaccine, reported in clinical trials from four continents. Methods All but three clinical trials were double-blind, randomized, and placebo-controlled. Study procedures and data collection methods were standardized. The frequency and severity of AEs reported during the first year of the trials were analyzed. To avoid confounding by vaccine-related events, solicited reactogenicity and other AEs occurring within 28 d after any vaccination were excluded. Results In total, 2134 AEs were reported by 76% of all participants; 73% of all events were mild. The rate of AEs did not differ between placebo and vaccine recipients. Overall, the percentage of participants with any AE was higher in Africa (83%) compared with Europe (71%), US (74%) and India (65%), while the percentage of participants with AEs of moderate or greater severity was similar in all regions except India. In all regions, the most frequently reported AEs were infectious diseases, followed by gastrointestinal disorders. Conclusions Despite some regional differences, in these healthy participants selected for low risk of HIV infection, background morbidity posed no obstacle to clinical trial conduct and interpretation. Data from controlled clinical trials of preventive interventions can offer valuable insights into the health of the eligible population.

Analysis of prion strains by PrPSc profiling in sporadic Creutzfeldt-Jakob disease.

BACKGROUND: Prion diseases are a group of invariably fatal neurodegenerative disorders affecting humans and a wide range of mammals. An essential part of the infectious agent, termed the prion, is composed of an abnormal isoform (PrPSc) of a host-encoded normal cellular protein (PrPC). The conversion of PrPC to PrPSc is thought to play a crucial role in the development of prion diseases and leads to PrPSc deposition, mainly in the central nervous system. Sporadic Creutzfeldt-Jakob disease (sCJD), the most common form of human prion disease, presents with a marked clinical heterogeneity. This diversity is accompanied by a molecular signature which can be defined by histological, biochemical, and genetic means. The molecular classification of sCJD is an important tool to aid in the understanding of underlying disease mechanisms and the development of therapy protocols. Comparability of classifications is hampered by disparity of applied methods and inter-observer variability. METHODS AND FINDINGS: To overcome these difficulties, we developed a new quantification protocol for PrPSc by using internal standards on each Western blot, which allows for generation and direct comparison of individual PrPSc profiles. By studying PrPSc profiles and PrPSc type expression within nine defined central nervous system areas of 50 patients with sCJD, we were able to show distinct PrPSc distribution patterns in diverse subtypes of sCJD. Furthermore, we were able to demonstrate the co-existence of more than one PrPSc type in individuals with sCJD in about 20% of all patients and in more than 50% of patients heterozygous for a polymorphism on codon 129 of the gene encoding the prion protein (PRNP). CONCLUSION: PrPSc profiling represents a valuable tool for the molecular classification of human prion diseases and has important implications for their diagnosis by brain biopsy. Our results show that the co-existence of more than one PrPSc type might be influenced by genetic and brain region-specific determinants. These findings provide valuable insights into the generation of distinct PrPSc types.

L'hyperréactivité bronchique et son importance pour le clinician [Bronchial hyperresponsiveness and its importance for the clinician].

Asthma is a chronic inflammatory airway disease, characterised by bronchial hyperresponsiveness causing bronchoconstriction, and thereby provoking typical symptoms (dyspnoea, cough, wheezing). Bronchial hyperres- ponsiveness indicates a temporary airflow limitation when exposed to a bronchoconstricting stimulus. Its measurement by challenge tests can be a valuable tool for confirming or excluding asthma, as well as for evaluating the efficacy of treatment. However, the origin of bronchial hyperresponsiveness is multifactorial and the different challenge tests are not equivalent. Direct challenge tests, like methacholine, mainly reflect chronic airway remo- delling, whereas indirect tests, like mannitol, better reflect bronchial inflammation.

Les combinaisons fixes de medicaments antihypertenseurs. [Fixed antihypertensive drug combinations]

Arterial hypertension is a highly heterogeneous condition. It is therefore not surprising that blood pressure lowering agents acting via a given mechanism allow a normalization of blood pressure in a fraction of hypertensive subjects only. The combination of drugs with different mechanisms of action on the cardiovascular system results in a considerably higher antihypertensive efficacy, not only with regard to the absolute blood pressure reduction but also in the number of responders. This effect is not achieved at the expenses of tolerance, because usually lower doses of the combined agents are sufficient to achieve the target blood pressure. The administration of antihypertensive agents in fixed combination has the advantage of its simplicity for both the physician as well as the patient. This aspect also explains the increasing popularity of fixed combinations as a valuable option in the initial treatment of the hypertensive patient.

Effect of groundwater composition on arsenic detection by bacterial biosensors.

A luminescent bacterial biosensor was used to quantify bioavailable arsenic in artificial groundwater. Its light production above the background emission was proportional to the arsenite concentration in the toxicologically relevant range of 0 to 0.5 mu M. Effects of the inorganic solutes phosphate, Fe(II) and silicate on the biosensor signal were studied. Phosphate at a concentration of 0.25 g L-1 phosphate slightly stimulated the light emission, but much less than toxicologically relevant concentrations of the much stronger inducer arsenite. No effect of phosphate was oberved in the presence of arsenite. Freshly prepared sodium silicate solution at a concentration of 10 g L-1 Si reduced the arsenite-induced light production by roughly 37%, which can be explained by transient polymerization leading to sequestration of some arsenic. After three days of incubation, silicate did not have this effect anymore, probably because depolymerization occurred. In the presence of 0.4 g L-1 Fe(II), the arsenite-induced light emission was reduced by up to 90%, probably due to iron oxidation followed by arsenite adsorption on the less soluble Fe(III) possibly along with some oxidation to the stronger adsorbing As(V). Addition of 100 mu M EDTA was capable of releasing all arsenic from the precipitate and to transform it into the biologically measurable, dissolved state. The biosensor also proved valuable for monitoring the effectiveness of an arsenic removal procedure based on water filtration through a mixture of sand and iron granules.

Potential value of biliary CEA assay in early detection of colorectal adenocarcinoma liver metastases.

Elevation of the biliary CEA level in patients with liver metastases from colorectal carcinoma has been reported. The aim of this study is to determine the potential value of biliary CEA assay in the early detection of liver metastases. Biliary and serum CEA levels were determined in patients operated on for a colorectal cancer and in control groups. Among 13 patients with liver metastases from colorectal carcinomas, biliary CEA levels were markedly elevated (> 40 ng/ml) in nine, moderately elevated (5-40 ng/ml) in two and normal (arbitrarily defined as < 5 ng/ml) in two. Of 28 patients with primary colorectal carcinoma without detectable hepatic secondaries, three had marked CEA elevation in the bile, 10 had moderate CEA elevation and 15 had normal levels. Among nine patients with non-malignant hepatobiliary pathology, there was one marked biliary CEA elevation, one moderate elevation and seven normal levels. None of the 13 individuals with no identified hepatobiliary pathology had elevated biliary CEA levels. The follow-up of patients with a primary colorectal tumour, no evidence of hepatic secondaries and a biliary CEA elevation is of particular interest. If subsequent appearance of liver metastases is found in such cases, intra-operative biliary CEA assay could be considered a valuable diagnostic test. Further studies will then have to prove the possible benefit of a specific treatment for this group of patients.

Position of indapamide , a diuretic with vasorelaxant activities, in antihypertensive therapy.

Introduction: Diuretics play a pivotal role in the management of hypertension. A large experience has been accumulated with indapamide , a long-acting thiazide-like diuretic that lowers blood pressure (BP) primarily through its natriuretic diuretic effect. Some of its long-term antihypertensive efficacy may be due to calcium antagonist-like vasorelaxant activities. Indapamide has protecting effects in a variety of conditions associated with high cardiovascular risk, such as diabetes, left ventricular hypertrophy, nephropathy and stroke. It is highly effective in lowering BP, whether given alone or in combination. Indapamide is well tolerated and has the advantage of having no adverse impact on glucose and lipid metabolism. Today, thiazide-like diuretics are regarded more and more as preferred drugs, when diuretic therapy is required to lower BP. Areas covered: The aim of this paper is to review the experience accumulated with indapamide. It is limited to clinical studies that are relevant for the everyday management of hypertensive patients, whether or not they exhibit cardiovascular or renal disease. Expert opinion: Indapamide, because of its well-documented beneficial effects on cardiovascular and renal outcomes, represents a safe and valuable option for treating patients with high BP. There is, however, still room for new trials evaluating the combination of this diuretic with other types of antihypertensive drugs, in particular a calcium antagonist such as amlodipine. There is also the need to compare the indapamide-perindopril and indapamide-amlodipine combinations, in terms of antihypertensive efficacy, tolerability and effects on target organ damage and, ideally, on cardiovascular mortality.

The profiling of MDMA tablets: a study of the combination of physical characteristics and organic impurities as sources of information

The profiling of MDMA tablets can be carried out using different sets of characteristics. The first type of measurements performed on MDMA tablets are physical characteristics (i.e. post-tabletting characteristics). They yield preliminary profiling data that may be valuable in a first stage for investigation purposes. However organic impurities (i.e. pre-tabletting characteristics) are generally considered to bring more reliable information, particularly for presentation of evidence in court. This work aimed therefore at evaluating the added value of combining pre-tabletting characteristics and post-tabletting characteristics of seized MDMA tablets. In approximately half of the investigated cases, the post-tabletting links were confirmed with organic impurities analyses. In the remaining cases, post-tabletting batches (post-TBs) were divided in several pre-tabletting batches (pre-TBs), thus supporting the hypothesis that several production batches of MDMA powder (pre-TBs) were used to produce one single post-TB (i.e. tablets having the same shape, diameter, thickness, weight and score; but different organic impurities composition). In view of the obtained results, the hypotheses were discussed through illustrating examples. In conclusion, both sets of characteristics were found relevant alone and combined together. They actually provide distinct information about MDMA illicit production and trafficking.

Paranasal sinuses in children: size evaluation of maxillary, sphenoid, and frontal sinuses by magnetic resonance imaging and proposal of volume index percentile curves.

Our objective was to establish the age-related 3D size of maxillary, sphenoid, and frontal sinuses. A total of 179 magnetic resonance imaging (MRI) of children under 17 years (76 females, 103 males) were included and sinuses were measured in the three axes. Maxillary sinuses measured at birth (mean+/-standard deviation) 7.3+/-2.7 mm length (or antero-posterior)/4.0+/-0.9 mm height (or cranio-caudal)/2.7+/-0.8 mm width (or transverse). At 16 years old, maxillary sinus measured 38.8+/-3.5 mm/36.3+/-6.2 mm/27.5+/-4.2 mm. Sphenoid sinus pneumatization starts in the third year of life after conversion from red to fatty marrow with mean values of 5.8+/-1.4 mm/8.0+/-2.3 mm/5.8+/-1.0 mm. Pneumatization progresses gradually to reach at 16 years 23.0+/-4.5 mm/22.6+/-5.8 mm/12.8+/-3.1 mm. Frontal sinuses present a wide variation in size and most of the time are not valuable with routine head MRI techniques. They are not aerated before the age of 6 years. Frontal sinuses dimensions at 16 years were 12.8+/-5.0 mm/21.9+/-8.4 mm/24.5+/-13.3 mm. A sinus volume index (SVI) of maxillary and sphenoid sinus was computed using a simplified ellipsoid volume formula, and a table with SVI according to age with percentile variations is proposed for easy clinical application. Percentile curves of maxillary and sphenoid sinuses are presented to provide a basis for objective determination of sinus size and volume during development. These data are applicable to other techniques such as conventional X-ray and CT scan.

Conditioning of stochastic 3-D fracture networks to hydrological and geophysical data

The geometry and connectivity of fractures exert a strong influence on the flow and transport properties of fracture networks. We present a novel approach to stochastically generate three-dimensional discrete networks of connected fractures that are conditioned to hydrological and geophysical data. A hierarchical rejection sampling algorithm is used to draw realizations from the posterior probability density function at different conditioning levels. The method is applied to a well-studied granitic formation using data acquired within two boreholes located 6 m apart. The prior models include 27 fractures with their geometry (position and orientation) bounded by information derived from single-hole ground-penetrating radar (GPR) data acquired during saline tracer tests and optical televiewer logs. Eleven cross-hole hydraulic connections between fractures in neighboring boreholes and the order in which the tracer arrives at different fractures are used for conditioning. Furthermore, the networks are conditioned to the observed relative hydraulic importance of the different hydraulic connections by numerically simulating the flow response. Among the conditioning data considered, constraints on the relative flow contributions were the most effective in determining the variability among the network realizations. Nevertheless, we find that the posterior model space is strongly determined by the imposed prior bounds. Strong prior bounds were derived from GPR measurements and helped to make the approach computationally feasible. We analyze a set of 230 posterior realizations that reproduce all data given their uncertainties assuming the same uniform transmissivity in all fractures. The posterior models provide valuable statistics on length scales and density of connected fractures, as well as their connectivity. In an additional analysis, effective transmissivity estimates of the posterior realizations indicate a strong influence of the DFN structure, in that it induces large variations of equivalent transmissivities between realizations. The transmissivity estimates agree well with previous estimates at the site based on pumping, flowmeter and temperature data.

New genetic models and mesenchymal cells as tools to ameliorate anti-tumor immunity

Résumé Le but final de ce projet est d'utiliser des cellules T ou des cellules souches mésenchymateuses modifiées génétiquement afin de surexprimer localement les deux chémokines CXCL13 et CCL2 ensemble ou chacune séparément à l'intérieur d'une tumeur solide. CXCL13 est supposé induire des structures lymphoïdes ectopiques. Un niveau élevé de CCL2 est présumé initier une inflammation aiguë. La combinaison des deux effets amène à un nouveau modèle d'étude des mécanismes régulateur de la tolérance périphérique et de l'immunité tumorale. Les connaissances acquises grâce à ce modèle pourraient permettre le développement ou l'amélioration des thérapies immunes du cancer. Le but premier de ce travail a été l'établissement d'un modèle génétique de la souris permettant d'exprimer spécifiquement dans la tumeur les deux chémokines d'intérêt à des niveaux élevés. Pour accomplir cette tâche, qui est en fait une thérapie génétique de tumeurs solides, deux types de cellules porteuses potentielles ont été évaluées. Des cellules CD8+ T et des cellules mésenchymateuses de la moelle osseuse transférées dans des receveurs portant une tumeur. Si on pouvait répondre aux besoins de la thérapie génétique, indépendamment de la thérapie immune envisagée, on posséderait là un outil précieux pour bien d'autres approches thérapeutiques. Plusieurs lignées de souris transgéniques ont été générées comme source de cellules CD8+ T modifiées afin d'exprimer les chémokines d'intérêt. Dans une approche doublement transgénique les propriétés de deux promoteurs spécifiques de cellules T ont été combinées en utilisant la technologie Cre-loxP. Le promoteur de granzyme B confère une dépendance d'activation et le promoteur distal de lck assure une forte expression constitutive dès que les cellules CD8+ T ont été activées. Les transgènes construits ont montré une bonne performance in vivo et des souris qui expriment CCL2 dans des cellules CD8+ T activées ont été obtenues. Ces cellules peuvent maintenant être utilisées avec différents protocoles pour transférer des cellules T cytotoxiques (CTL) dans des receveurs porteur d'une tumeur, permettant ainsi d'évaluer leur capacité en tant que porteuse de chémokine d'infiltrer la tumeur. L'établissement de souris transgéniques, qui expriment pareillement CXCL13 est prévu dans un avenir proche. L'évaluation de cellules mésenchymateuses de la moelle osseuse a démontré que ces cellules se greffent efficacement dans le stroma tumoral suite à la co-injection avec des cellules tumorales. Cela représente un outil précieux pour la recherche, vu qu'il permet d'introduire des cellules manipulées dans un modèle tumoral. Les résultats confirment partiellement d'autres résultats rapportés dans un modèle amélioré. Cependant, l'efficacité et la spécificité suggérées de la migration systémique de cellules mésenchymateuses de la moelle osseuse dans une tumeur n'ont pas été observées dans notre modèle, ce qui indique, que ces cellules ne se prêtent pas à une utilisation thérapeutique. Un autre résultat majeur de ce travail est l'établissement de cultures de cellules mésenchymateuses de la moelle osseuse in vitro conditionnées par des tumeurs, ce qui a permis à ces cellules de s'étendre plus rapidement en gardant leur capacité de migration et de greffe. Cela offre un autre outil précieux, vu que la culture in vitro est un pas nécessaire pour une manipulation thérapeutique. Abstract The ultimate aim of the presented project is to use genetically modified T cells or mesenchymal stem cells to locally overexpress the two chemokines CXCL13 and CCL2 together or each one alone inside a solid tumor. CXCL13 is supposed to induce ectopic lymphoid structures and a high level of CCL2 is intended to trigger acute inflamation. The combination of these two effects represents a new model for studying mechanisms that regulate peripheral tolerance and tumor immunity. Gained insights may help developing or improving immunotherapy of cancer. The primary goal of the executed work was the establishment of a genetic mouse model that allows tumor-specific expression of high levels of the two chemokines of interest. For accomplishing this task, which represents gene therapy of solid tumors, two types of potentially useful carrier cells were evaluated. CD8+ T cells and mesenchymal bone marrow cells to be used in adoptive cell transfers into tumor-bearing mice. Irrespectively of the envisaged immunotherapy, satisfaction of so far unmet needs of gene therapy would be a highly valuable tool that may be employed by many other therapeutic approaches, too. Several transgenic mouse lines were generated as a source of CD8+ T cells modified to express the chemokines of interest. In a double transgenic approach the properties of two T cell-specific promoters were combined using Cre-loxP technology. The granzyme B promoter confers activation-dependency and the lck distal promoter assures strong constitutive expression once the CD8+ T cell has been activated. The constructed transgenes showed a good performance in vivo and mice expressing CCL2 in activated CD8+ T cells were obtained. These cells can now be used with different protocols for adoptively transferring cytotoxic T cells (CTL) into tumor-bearing recipients, thus allowing to study their capacity as tumor-infiltrating chemokine carrier. The establishment of transgenic mice likewisely expressing CXCL13 is expected in the near future. In addition, T cells from generated single transgenic mice that have high expression of an EGFP reporter in both CD4+ and CD8+ cells can be easily traced in vivo when setting up adoptive transfer conditions. The evaluation of mesenchymal bone marrow cells demonstrated that these cells can efficiently engraft into tumor stroma upon local coinjection with tumor cells. This represents a valuable tool for research purposes as it allows to introduce manipulated stromal cells into a tumor model. Therefore, the established engraftment model is suited for studying the envisaged immunotherapy. These results confirm to some extend previously reported results in an improved model, however, the suggested systemic tumor homing efficiency and specificity of mesenchymal bone marrow cells was not observed in our model indicating that these cells may not be suited for therapeutic use. Another major result of the presented work is the establishment oftumor-conditioned in vitro culture of mesenchymal bone marrow cells, which allowed to more rapidly expand these cells while maintaining their tumor homing and engrafting capacities. This offers another valuable tool as in vitro culture is a necessary step for therapeutic manipulations.