The surface atlas of human naive and activated CD4+ T cells

Naive CD4+ T cells are the precursor cells of all effector T helper cell subsets and they form the basis of the immunologic memory. These cells provide one of the earliest cellular targets to modulate T cell activation and differentiation during the development of CD4+ T cell driven immune pathologies such as autoimmune diseases and allergies, which are an in-creasing problem for the worlds’ societies. Easy accessible cell surface proteins are responsi-ble for the recognition of and response to signals of other cells or changes in the environ-ment, therefore, they can be described as interesting targets for immune modulation strate-gies such as immunotherapy and vaccination. The aim of this dissertation is to characterize the proteomic cell surface composition of human naive CD4+ T cells and their changes during T cell activation on a multi-omic level to deepen the current knowledge about these im-portant immune cells and to identify new immune targets for the development of novel im-mune modulation strategies. Human naive CD4+ T cells were isolated and activated with an-ti-CD3/anti-CD28 in a time course experiment to mimic T cell receptor engagement. The samples were analyzed via a non-targeted proteomic technique (PAL-qLC-MS/MS), a target-ed flow cytometry screen and a genome-wide microarray expression analysis coupled to bioinformatics analyses. All obtained results were combined in the surface atlas of human naive and activated CD4+ T cells. Out of the analyzed multi-omic datasets, the transmem-brane protein c16orf54 was chosen for further investigations and tools such as monoclonal antibodies, stable expression systems and murine model organisms were generated. 229 cell surface proteins were identified and quantified on human naive and activated CD4+ T cells by the proteomic techniques and 927 cell surface protein coding transcripts were detected by the transcriptomic analyses. 51 of the cell surface proteins are annotated as targets for ap-proved drugs and further interesting cell surface targets such as solute carrier transport pro-teins and proteins, which were not described in the context of T cell biology before, like the transmembrane protein c16orf54, were identified by analyses of the multi-omic datasets. Newly generated investigational tools revealed that c16orf54 is not only expressed on naive and activated CD4+ T cells within the compartment of immune cells in the blood. The generated surface atlas of human naive and activated CD4+ T cells can be seen as multi-omic reference guide for CD4+ T cell activation, increasing the current knowledge of CD4+ T cell biology. In addition, it provides a rich source of interesting immune targets, which can be investigated in the context of novel therapeutic strategies aiming to modulate reactions of the immune system during the development of CD4+ T cell driven diseases

The surface atlas of human naive and activated CD4+ T cells

Naive CD4+ T cells are the precursor cells of all effector T helper cell subsets and they form the basis of the immunologic memory. These cells provide one of the earliest cellular targets to modulate T cell activation and differentiation during the development of CD4+ T cell driven immune pathologies such as autoimmune diseases and allergies, which are an in-creasing problem for the worlds’ societies. Easy accessible cell surface proteins are responsi-ble for the recognition of and response to signals of other cells or changes in the environ-ment, therefore, they can be described as interesting targets for immune modulation strate-gies such as immunotherapy and vaccination. The aim of this dissertation is to characterize the proteomic cell surface composition of human naive CD4+ T cells and their changes during T cell activation on a multi-omic level to deepen the current knowledge about these im-portant immune cells and to identify new immune targets for the development of novel im-mune modulation strategies. Human naive CD4+ T cells were isolated and activated with an-ti-CD3/anti-CD28 in a time course experiment to mimic T cell receptor engagement. The samples were analyzed via a non-targeted proteomic technique (PAL-qLC-MS/MS), a target-ed flow cytometry screen and a genome-wide microarray expression analysis coupled to bioinformatics analyses. All obtained results were combined in the surface atlas of human naive and activated CD4+ T cells. Out of the analyzed multi-omic datasets, the transmem-brane protein c16orf54 was chosen for further investigations and tools such as monoclonal antibodies, stable expression systems and murine model organisms were generated. 229 cell surface proteins were identified and quantified on human naive and activated CD4+ T cells by the proteomic techniques and 927 cell surface protein coding transcripts were detected by the transcriptomic analyses. 51 of the cell surface proteins are annotated as targets for ap-proved drugs and further interesting cell surface targets such as solute carrier transport pro-teins and proteins, which were not described in the context of T cell biology before, like the transmembrane protein c16orf54, were identified by analyses of the multi-omic datasets. Newly generated investigational tools revealed that c16orf54 is not only expressed on naive and activated CD4+ T cells within the compartment of immune cells in the blood. The generated surface atlas of human naive and activated CD4+ T cells can be seen as multi-omic reference guide for CD4+ T cell activation, increasing the current knowledge of CD4+ T cell biology. In addition, it provides a rich source of interesting immune targets, which can be investigated in the context of novel therapeutic strategies aiming to modulate reactions of the immune system during the development of CD4+ T cell driven diseases

Scattered Light Imaging: Resolving the substructure of nerve fiber crossings in whole brain sections with micrometer resolution

For developing a detailed network model of the brain based on image reconstructions, it is necessary to spatially resolve crossing nerve fibers. The accuracy hereby depends on many factors, including the spatial resolution of the imaging technique. 3D Polarized Light Imaging (3D-PLI) allows the three-dimensional reconstruction of nerve fiber tracts in whole brain sections with micrometer in-plane resolution, but leaves uncertainties in pixels containing crossing fibers. Here we introduce Scattered Light Imaging (SLI) to resolve the substructure of nerve fiber crossings. The measurement is performed on the same unstained histological brain sections as in 3D-PLI. By illuminating the brain sections from different angles and measuring the transmitted (scattered) light under normal incidence, SLI provides information about the underlying nerve fiber structure. A fully automated evaluation of the resulting light intensity profiles has been developed, allowing the user to extract various characteristics, like the individual directions of in-plane crossing nerve fibers, for each image pixel at once. We validate the reconstructed nerve fiber directions against results from previous simulation studies, scatterometry measurements, and fiber directions obtained from 3D-PLI. We demonstrate in different brain samples (human optic tracts, vervet monkey brain, rat brain) that the 2D fiber directions can be reliably reconstructed for up to three crossing nerve fiber bundles in each image pixel with an in-plane resolution of up to 6.5 $\mu$m. We show that SLI also yields reliable fiber directions in brain regions with low 3D-PLI signals coming from regions with a low density of myelinated nerve fibers or out-of-plane fibers. In combination with 3D-PLI, the technique can be used for a full reconstruction of the three-dimensional nerve fiber architecture in the brain.Comment: 30 pages, 16 figure

Alcohol consumption and binge drinking in adolescents: comparison of different migration backgrounds and rural vs. urban residence - a representative study

Background Binge drinking is a constant problem behavior in adolescents across Europe. Epidemiological investigations have been reported. However, epidemiological data on alcohol consumption of adolescents with different migration backgrounds are rare. Furthermore representative data on rural-urban comparison concerning alcohol consumption and binge drinking are lacking. The aims of the study are the investigation of alcohol consumption patterns with respect to a) urban-rural differences and b) differences according to migration background. Methods In the years 2007/2008, a representative written survey of N = 44,610 students in the 9th. grade of different school types in Germany was carried out (net sample). The return rate of questionnaires was 88% regarding all students whose teachers respectively school directors had agreed to participate in the study. Weighting factors were specified and used to make up for regional and school-type specific differences in return rates. 27.4% of the adolescents surveyed have a migration background, whereby the Turkish culture is the largest group followed by adolescents who emigrated from former Soviet Union states. The sample includes seven large cities (over 500,000 inhabitants) (12.2%), independent smaller cities ("urban districts") (19.0%) and rural areas ("rural districts") (68.8%). Results Life-time prevalence for alcohol consumption differs significantly between rural (93.7%) and urban areas (86.6% large cities; 89.1% smaller cities) with a higher prevalence in rural areas. The same accounts for 12-month prevalence for alcohol consumption. 57.3% of the rural, re-spectively 45.9% of the urban adolescents engaged in binge drinking in the 4 weeks prior to the survey. Students with migration background of the former Soviet Union showed mainly drinking behavior similar to that of German adolescents. Adolescents with Turkish roots had engaged in binge drinking in the last four weeks less frequently than adolescents of German descent (23.6% vs. 57.4%). However, in those adolescents who consumed alcohol in the last 4 weeks, binge drinking is very prominent across the cultural backgrounds. Conclusions Binge drinking is a common problem behavior in German adolescents. Obviously adolescents with rural residence have fewer alternatives for engaging in interesting leisure activities than adolescents living in cities. This might be one reason for the more problematic consumption patterns there. Common expectations concerning drinking behavior of adolescents of certain cultural backgrounds ('migrants with Russian background drink more'/'migrants from Arabic respectively Oriental-Islamic countries drink less') are only partly affirmed. Possibly, the degree of acculturation to the permissive German alcohol culture plays a role here

Counsellors contact dementia caregivers - predictors of utilisation in a longitudinal study

<p>Abstract</p> <p>Background</p> <p>Counselling of family members is an established procedure in the support of dementia patients' relatives. In absence of widespread specialised dementia care services in most countries, however, counselling services are often not taken up or only very late in the course of the disease.</p> <p>Object</p> <p>In order to promote acceptance of this service, a new counselling concept was implemented where general practitioners recommended family counsellors, who then actively contacted the family caregivers to offer counselling ("Counsellors Contact Caregivers", CCC). The research questions were: To what extent can the rate of family counselling be increased by CCC? What are the predictors for usage of this form of family counselling?</p> <p>Methods</p> <p>The study started in June 2006 in Middle Franconia for patients with mild to moderate dementia. At baseline, 110 family caregivers were offered counselling based on the CCC guideline. Data was analysed from 97 patient-caregiver dyads who received counselling for one year. The mean age of the patients with dementia (67 women and 30 men) was 80.7 years (SD = 6.2). The mean age of their primary family caregivers (68 women, 23 men) was 60.8 years (SD = 13.8).</p> <p>Results</p> <p>35 family members (36%) made use of more extensive counselling (more than one personal contact). By contrast, 29 family members (30%) had no personal contact or only one personal contact (33 cases, 34%). The factors "spouse" (p = .001) and "degree of care" (p = .005) were identified as significant predictors for acceptance of extensive counselling.</p> <p>Conclusions</p> <p>Actively contacting patients and their caregivers is a successful means of establishing early and frequent contact with family members of patients with mild to moderate dementia. Use of extensive counselling is made especially by spouses of patients requiring intensified care.</p> <p>Trial Registration</p> <p>ISRCTN68329593</p

Support groups for dementia caregivers - Predictors for utilisation and expected quality from a family caregiver's point of view: A questionnaire survey PART I*

<p>Abstract</p> <p>Background</p> <p>Support groups have proved to be effective in reducing the burden on family caregivers of dementia patients. Nevertheless, little is known about the factors that influence utilisation or quality expectations of family caregivers. These questions are addressed in the following paper.</p> <p>Methods</p> <p>The cross-sectional study was carried out as an anonymous written survey of family caregivers of dementia patients in Germany. Qualitative and quantitative data from 404 caregivers were analysed using content analysis and binary logistic regression analysis.</p> <p>Results</p> <p>The only significant predictor for utilisation is assessing how helpful support groups are for the individual care situation. Family caregivers all agree that psycho-educative orientation is a priority requirement.</p> <p>Conclusions</p> <p>In order to increase the rate of utilisation, family caregivers must be convinced of the relevant advantages of using support groups. Support groups which offer an exchange of experiences, open discussion, information and advice meet the requirements of family caregivers.</p

Towards Ultra-High Resolution Fibre Tract Mapping of the Human Brain – Registration of Polarised Light Images and Reorientation of Fibre Vectors

Polarised light imaging (PLI) utilises the birefringence of the myelin sheaths in order to visualise the orientation of nerve fibres in microtome sections of adult human post-mortem brains at ultra-high spatial resolution. The preparation of post-mortem brains for PLI involves fixation, freezing and cutting into 100-μm-thick sections. Hence, geometrical distortions of histological sections are inevitable and have to be removed for 3D reconstruction and subsequent fibre tracking. We here present a processing pipeline for 3D reconstruction of these sections using PLI derived multimodal images of post-mortem brains. Blockface images of the brains were obtained during cutting; they serve as reference data for alignment and elimination of distortion artefacts. In addition to the spatial image transformation, fibre orientation vectors were reoriented using the transformation fields, which consider both affine and subsequent non-linear registration. The application of this registration and reorientation approach results in a smooth fibre vector field, which reflects brain morphology. PLI combined with 3D reconstruction and fibre tracking is a powerful tool for human brain mapping. It can also serve as an independent method for evaluating in vivo fibre tractography

Effects of general practitioner training and family support services on the care of home-dwelling dementia patients - Results of a controlled cluster-randomized study

<p>Abstract</p> <p>Background</p> <p>More than 90% of dementia patients are cared for by their general practitioners, who are decisively involved in the diagnosis, therapy and recommendation of support services. <it>Objective: </it>To test whether special training of general practitioners alters the care of dementia patients through their systematic recommendation of caregiver counseling and support groups.</p> <p>Method</p> <p>129 general practitioners enrolled 390 dementia patients and their informal caregivers in a prospective, three-arm cluster-randomized 2-year study. Arm A constituted usual care, in Arm B and C support groups and caregiver counseling (in Arm B one year after baseline, in Arm C at baseline) were recommended by the general practitioners. The general practitioners received arm-specific training. Diagnostic and therapeutic behavior of physicians was recorded at baseline. Informal caregivers were questioned in follow-up after 2 years about the utilization of support services.</p> <p>Results</p> <p>The diagnostic behavior of the general practitioners conforms to relevant guidelines. The procedure in newly-diagnosed patients does not differ from previously diagnosed patients with the exception of the rate of referral to a specialist. About one-third of the newly-diagnosed dementia patients are given an anti-dementia drug. The utilization of support groups and counseling increased five- and fourfold, respectively. Utilization of other support services remained low (< 10%), with the exception of home nursing and institutional short-term nursing.</p> <p>Conclusion</p> <p>Trained general practitioners usually act in conformity with guidelines with respect to diagnosing dementia, and partly in conformity with the guidelines with respect to recommended drug therapy. Recommendations of support services for informal caregivers by the general practitioner are successful. They result in a marked increase in the utilization rate for the recommended services compared to offers which are not recommended by the general practitioner.</p> <p>Trial registration</p> <p>ISRCTN68329593</p