Abstract Previous studies have shown that intracellular adenosine triphosphate (iATP) in activated CD4 T cells in vitro may identify patients at risk of infection or rejection post-transplantation. ...In this study, we evaluated whether this test could identify the level of risk in 656 renal transplant recipients (RTRs) with good and stable graft function. Therefore, 1095 blood samples from RTRs and 200 from healthy blood donors (normal controls NCs) were collected in 2 years and analyzed using the Cylex® ImmuKnow™ assay (Cylex, Inc., Columbia, MD, USA). The classification of T cell responses into strong, moderate, and low revealed significant differences between patients and NCs in low and strong responses ( P < .001 and P = .021, respectively). The majority of patient samples exhibited moderate immune response (72.2%) in comparison with NC (75%). One hundred twenty-eight patients had fluctuated T cell responses between the three response zones. All patients were clinically stable for at least 1 month after the test. T cell response was increased after time post-transplantation ( P < .001) and was found higher in protocols using azathioprine versus other immunosuppression ( P < .001) and cyclosporine instead of tacrolimus ( P = .012). According to the results of this study, we are not able to support this assay as an immune monitoring test post-transplantation in clinically stable RTRs. In contrast, measuring of iATP in CD4 T cells is a valuable tool for estimating T cell activation capacity. Because T cell activation is mainly affected by immunosuppression, this test may give information regarding the strength of different immunosuppressive protocols or the strength of immunosuppression as it is associated with longer follow-up periods.
Chlamydia trachomatis: time for screening? Spiliopoulou, A.; Lakiotis, V.; Vittoraki, A. ...
Clinical microbiology and infection,
September 2005, Letnik:
11, Številka:
9
Journal Article
Recenzirano
Odprti dostop
Genital Chlamydia trachomatis infection is the leading cause of bacterial sexually transmitted disease in industrialised countries, particularly among young people. The consequences of chlamydial ...infection may involve urethritis, cervicitis, pelvic inflammatory disease, ectopic pregnancy, tubal factor infertility, epididymitis and prostatitis. In addition, chlamydial infection increases the risk of acquisition of human immunodeficiency virus and has been associated with cervical cancer. Although screening programmes exist in a number of countries, the continuously increasing prevalence of chlamydial infections demonstrates the necessity for health authorities to establish effective screening policies, and the importance of defining a comprehensive European screening policy is emerging.
Tumour markers are neither sensitive nor specific enough for cancer screening. Despite established guidelines, tumour marker ‘screening myth’ may be alive among physicians, but no study has analysed ...the phenomenon. This study aims to investigate tumour marker recommendation for screening purposes in primary care setting. A total of 209 Hellenic physicians were surveyed for screening activities by a multiple‐choice questionnaire. Data were ed for the following tumour marker recommendations: carcinoembryonic antigen (CEA); cancer antigens 19.9, 125 and 15.3; alpha‐fetoprotein and β‐human chorionic gonadotropin (β−HCG). A high rate of physicians advocate that tumour markers in cancer screening (range from 24% for β‐HCG to 46% for CEA).This phenomenon is not related to age, sex, type and level of physicians’ specialization. In conclusion, many physicians recommend tumour markers for screening purposes. This may be harmful, since their prescriptions unnecessarily burden health economics, and further evaluation of false‐positive findings might be associated with increased costs and risk from additional diagnostic/therapeutic interventions.
Cancer is the second cause of death in developed countries. Many efforts to educate the public to more tumor free life-style and screening practice have been therefore adopted. Considering the high ...costs of diagnostic procedures and educational programs a cancer prevention/screening practice monitoring system is required to reduce costs, to assist health making policy decisions, and to tailor more targeted interventions whenever indicated. We, therefore, realized a computerized data-base able to assist medical personnel in health intervention monitoring and making policy at community level with a focus on the European region. An international medical board provided the translation of medical-related contents in English, French, German, Greek, Italian, Rumanian, Spanish and Turkish. The electronic system recognizes and finds relationships between screening events or secondary prevention tests and various causes of medical examinations (symptoms, diseases, professions, presence and type of health insurance, sex, age, medical history, family history, educational level, knowledge about cancer screening and prevention, patient location, type of community, region of provenance, etc). Due to its multi-language standardized characteristics its application may bridge European countries in cancer screening monitoring policy.
Allele specific antibody response against the polymorphic system of HLA is the allogeneic response marker determining the immunological risk for graft acceptance before and after organ ...transplantation and therefore routinely studied during the patient's workup. Experimentally, bead bound antigen- antibody reactions are detected using a special multicolor flow cytometer (Luminex). Routinely for each sample, antibody responses against 96 different HLA antigen groups are measured simultaneously and a 96-dimensional immune response vector is created. Under a common experimental protocol, using unsupervised clustering algorithms, we analyzed these immune intensity vectors of anti HLA class II responses from a dataset of 1,748 patients before or after renal transplantation residing in a single country. Each patient contributes only one serum sample in the analysis. A population view of linear correlations of hierarchically ordered fluorescence intensities reveals patterns in human immune responses with striking similarities with the previously described CREGs but also brings new information on the antigenic properties of class II HLA molecules. The same analysis affirms that "public" anti-DP antigenic responses are not correlated to anti DR and anti DQ responses which tend to cluster together. Principal Component Analysis (PCA) projections also demonstrate ordering patterns clearly differentiating anti DP responses from anti DR and DQ on several orthogonal planes. We conclude that a computer vision of human alloresponse by use of several dimensionality reduction algorithms rediscovers proven patterns of immune reactivity without any a priori assumption and might prove helpful for a more accurate definition of public immunogenic antigenic structures of HLA molecules. Furthermore, the use of Eigen decomposition on the Immune Response generates new hypotheses that may guide the design of more effective patient monitoring tests.
Current pre-transplantation routine matching involves serum anti-HLA antibodies quantification but cannot always preclude unfavorable graft outcomes. Epitope-based matching is proposed as a more ...precise approach, but to date no epitope-matching algorithm provides a satisfactory predictive tool for transplantation outcomes. In this study, anti-HLA-II loci responses from 1748 patients were analyzed with unsupervised machine learning algorithms, namely principal component analysis (PCA) and antigenic distances, projected as dendrograms. PCA for anti-HLA-DR anti-bodies revealed three main clusters of responses: anti-HLA-DR51 combined with anti-HLA-DRB1*01, anti-HLA-DR52 combined with anti-HLA-DRB1*08 and anti-HLA-DR53 combined with anti-HLA-DRB1*10. The dendrogram for anti-HLA-DR confirmed the pattern and showed further bisection of each cluster. Common epitopes present exclusively in all HLA molecules of each cluster were determined following the HLA epitope registry. Thus, we propose that 19 out of 123 HLA-DR epitopes are those that mainly lead anti-HLA-DR responses in the studied population. Likewise, we identified 22 out of 83 epitopes responsible for anti-HLA-DQ and 13 out of 62 responsible for anti-HLA-DP responses. Interpretation of these results may elucidate mechanisms of interlocus cross-reactivity, providing an alternative way of estimating the significance of each epitope in a population and thus suggesting a novel strategy towards optimal donor selection.
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