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Résumé: Objectif: L’antigène leucocytaire humain HLA-B27 est un antigène de classe I du complexe majeur d’histocompatibilité étroitement associé à la spondylarthrite ankylosante (SA) et autres spondylarthropathies associées (SpAs). Le mécanisme de cette association reste inconnu. HLA-B27 est une spécificité sérologique qui représente une famille d’au moins 25 allèles HLA-B27 différents (2701–2725). Ces allèles sont étroitement liés par une homologie de la séquence nucléotidique mais diffèrent dans leur distribution ethnique. L’objectif de cette étude est d’analyser la distribution des allèles HLA-B27 chez des témoins sains et chez des patients atteints de spondylarthrite ankylosante (SA). Méthode: Nous avons sélectionné 160 personnes HLA-B27 positives (39 témoins et 121 patients atteints de SA). Le typage des allèles HLA-B27 et Cw a été réalisé par la réaction de polymérisation en chaîne avec amorces spécifiques à la séquence (PCR–SSP) et par typage sérologique (technique de microlymphotoxicité). Résultats: Sept sous-types B * 27 ont été identifies : B * 2702, 03, 04, 05, 07, 09 et B * 2714. La distribution de ces allèles dans la population de patients était : B * 2702 (47,1 %) et : B * 2705 (47,1 %). Ces sous-types étaient aussi détectés chez 16 (41 %) et 16 (41 %), respectivement des 39 témoins sains. HLA-B2707 était détecté chez quatre patients (3,31 %) et chez trois témoins (7,6 %). B * 2704 et B * 2714 étaient relativement rares et n’ont été détectés que chez un seul sujet chaque. Aucune différence significative n’a été observée dans la fréquence et la distribution des allèles HLA-B27 entre les patients et les témoins. Conclusion: Nos résultats montrent un nombre restreint de sous-types HLA-B27 associés à la SA. B * 2702 et B * 2705 étaient aussi courants chez les patients que chez les témoins. Les haplotypes B27/Cw les plus proéminents dans les groupes de patients et de témoins étaient : B * 2702/Cw02022 et : B * 2705/Cw02022. [Copyright &y& Elsevier]

Infliximab (IFX) is a chimeric monoclonal antibody which has proven its efficacy in the treatment of inflammatory diseases. However, its efficacy can be limited by the development of anti-IFX antibodies (ATI) resulting in a therapeutic failure of IFX. ATI plasmatic monitoring is then indicated to optimize IFX treatment. The aim of this study was to validate an ELISA (enzyme linked immuno sorbent assay) method of ATI plasmatic monitoring., Methods: Assessment of performance was based on the study of correlation and concordance (Bland Altman method) of the absorbances measured by the two readers. ELISA kit validation was made by calculating the accuracy and the exactitude., Results: We collected 23 samples. Their mean age was 46 years and sex ratio M/W was 0.92. In nine cases, plasmatic AIT were positive and in 14 cases, they were not detected. Correlation between the two readers showed a correlation coefficient r 2 of 99.95%. Concordance limits of the confidence interval 95% were [-112.768%-41.425%] with a bias of -35.671%. Repeatability and reproductibility were checked by a positive control and coefficients of variation were respectively of 5.574% and 14.184%. Limits of detection and quantification were respectively of 0.046 and 0.086. The positive predictive value was 0.5 and the negative predictive value was 1. The sensitivity was 100% and the specificity was 83%., Conclusion: The assessment of the performance of the tested microplate reader and the validation of the tested ELISA kit showed good results allowing ATI routine measurement to optimize therapeutic management of patients treated by IFX.

Epithelial-mesenchymal transition (EMT) is a process by which differentiated epithelial cells undergo a phenotypic conversion and acquire a mesenchymal phenotype, including elongated morphology, enhanced migratory and invasion capacity, and greatly increased production of extracellular matrix (ECM) components. This phenomenon plays a pivotal role in embryonic development, wound healing and tissue regeneration. It has also been involved in organ fibrosis. Some studies suggest that following injury, renal tubular epithelial cells undergo reprograming in mesenchymal cells, and thus constitute an important source of de novo myofibroblasts invading the renal interstitium and contributing to fibrosis. However, an increasing number of studies raise doubts about the existence of this process in vivo. The role of EMT in the development of renal fibrosis remains a matter of intense debate and may depend on the model studied. In this review, we describe the role of EMT in the development of fibrosis of renal graft, and then we propose approaches for detecting and treating renal fibrogenesis by targeting TEM., (© 2015 médecine/sciences – Inserm.)

Background: Hepatitis viral C (HVC) is relatively frequent among kidney transplants. It is responsible for a morbid-mortality that compromises the results of transplantation in the medium and long term., Aim: To evaluate and to compare the prevalence of HVC, 172 kidney transplant adult patients were investigated in two Maghrebian centers at Casablanca (G1): 57 Moroccan patients and Tunisia (G2):.115 Tunisian patients. The impact of the HVC infection for a morbid-mortality was concerned only the Tunisian recipient patients: 20 kidney recipients having antibodies anti-VHC and positive HVC-RNA (Cases) which were matched in age, sex and date of the kidney graft, to 20 kidney transplant patients anti-HVC and VHCRNA negative (Controls)., Methods: The anti-VHC antibodies were detected by ELISA: Innogenetics and their positivity were confirmed by RIBAII. The ARN-VHC was analyzed by RT-PCR INNO-LiPA HCV II amplification of Innogenetics., Results: The prevalence of hepatitis C is similar for the two groups: 19.3% among Moroccan kidney transplants and 20.9% among Tunisians. The infection by the HVC was often active and the detection of viral RNA was found in 91.7% of the G2 patients against 50% among G1 patients. The genotype 1b is the most prevalent; it is found in 59% of the patients. The frequency of HVC among our kidney transplant patients is particularly determined by the duration and the mode of dialysis. In fact, 22.1% of the patients treated by hemodialysis are VHC (+) against 5,6% patients treated by peritoneal dialysis. Also, the average duration of the dialysis is 58,8 months for HVC (+) patients against 33.5 months for HVC (-) (p<0.0001) patients. The frequency of the chronic rejection of the graft is higher in the G2, but it is similar in Tunisian patients with or without antibodies anti-HVC. In the G1, this frequency is statistically higher among positive HVC transplant patients compared to the negative HVC grafted patients (p<0.05). The case-control study emphasizes the frequency of the proteinuria, the renal insufficiency, the mellitensis diabetes and the polyglobulinemia among patients HCV (+); however the differences between the two groups remain statistically non significant. The total rate of the hospitalizations is 26 per 100 patients per year in the HCV (+) group against 17 for the HCV (-). The average duration of hospitalizations is 72 days among HCV (+) patients against 30.2 days for the controls (p<0.05). The averages of survival of the patients and of the controls were similar 11.6±5.6 years for transplant patient HCV (+) against 11.2±5.5 years for the controls. The actuarial curves of the patients were not different for the patients having antibodies anti-HCV positive or negative., Conclusion: The blood and nosocomial modes of contamination of HVC infection explain their higher frequency in this population at risk. The mortality and the morbidity of the renal transplant patients infected by the HCV seem to be higher compared to the uninfected patients. A further study by large population should be carried out to confirm these results.