Impact of IL-10 gene promoter polymorphisms on treatment response in HCV patients: A systematic review, a meta-analysis, and a meta-regression.

The impact of interleukin-10 (IL-10) gene promoter polymorphisms (SNPs) on treatment response in HCV patients was dissimilarly estimated. Hence, the aim of this meta-analysis was to robustly assess the effect of IL-10 SNPs on treatment response in HCV patients. An electronic literature search was carried out through PubMed, EMBASE, Web of science, and Scopus databases. Studies assessing the association between IL-10 polymorphisms and treatment response in HCV patients were included. Studies were excluded if genotype frequencies are not consistent with the Hardy-Weinberg Equilibrium (HWE) or in case of including patients with hepatitis B virus coinfection. Risk of bias in included studies was assessed using the Newcastle-Ottawa Scale. Meta-analyses were performed for the influence of IL-10 gene promoter SNPs (rs1800896 (-1082 A/G), rs1800871 (-819 C/T), and rs1800872 (-592 C/T)) and haplotypes on treatment response in HCV patients. Subgroup analyses, meta-regressions, publication bias assessment, and sensitivity analyses were also conducted. Overall, 32 studies with a total of 5943 HCV cases and 2697 controls were included in the present study. The -1082*G allele was significantly associated with increased risk of non-response (NR) to treatment, OR [95% CI] = 1.29 [1.1-1.51], p = .002. Besides, the rs1800872 -592*C allele was significantly associated with increased NR risk, OR [95% CI] = 1.22 [1.02-1.46], p = .03. Subgroup analysis showed that this association remained significant only in patients treated with PEG-IFN alone, p = .01. The -1082*G/-819*C/-592*C (GCC) haplotype was significantly associated with increased NR risk, OR [95% CI] = 1.62 [1.13-2.23], p = .009. Our results suggest that the IL-10 rs1800896 was associated with NR risk especially in North-African and Asian populations. Moreover, the IL-10 gene promoter -1082*G/-819*C/-592*C (GCC) haplotype which has been associated with higher production of IL-10, was significantly associated with increased NR risk.

Knowledge and Attitudes Toward Organ Donation Among Tunisian Adults: Results of a National Survey.

OBJECTIVES: Attitudes and knowledge toward organ donation can influence a person's willingness to donate. The aim of this study was to assess attitudes and knowledge regarding organ donation among Tunisian adults. MATERIALS AND METHODS: We conducted a crosssectional survey at the national level from January 23 to February 15, 2017, among 1026 Tunisian adults. We used a standardized questionnaire to collect data by phone call. We performed statistical analyses with Stata software (version 11). RESULTS: The study included 495 male and 531 female participants. Forty-one percent of participants were 18 to 30 years old. In total, 81.7% had heard about organ donation. Fewer than half of respondents (47.8%) were aware that organ donation is regulated. In total, 80.7% accepted to donate their organs after death, and 32.2% had mentioned their opinion to relatives or friends. Only 1% had added their donor status on their national identity cards. CONCLUSIONS: Tunisian adults seem to have positive attitudes regarding organ donation. However, the proportion of respondents who included their donor status on their national identity cards was low. It is important to enhance information and education on organ donation in an effort to mitigate the shortage of organs.

Development and comparative evaluation of SARS-CoV-2 S-RBD and N based ELISA tests in various African endemic settings.

Management of the COVID-19 pandemic relies on molecular diagnostic methods supported by serological tools. Herein, we developed S-RBD- and N- based ELISA assays useful for infection rate surveillance as well as the follow-up of acquired protective immunity against SARS-CoV-2. ELISA assays were optimized using COVID-19 Tunisian patients' sera and prepandemic controls. Assays were further validated in 3 African countries with variable endemic settings. The receiver operating curve was used to evaluate the assay performances. The N- and S-RBD-based ELISA assays performances, in Tunisia, were very high (AUC: 0.966 and 0.98, respectively, p < 0.0001). Cross-validation analysis showed similar performances in different settings. Cross-reactivity, with malaria infection, against viral antigens, was noticed. In head-to-head comparisons with different commercial assays, the developed assays showed high agreement. This study demonstrates, the added value of the developed serological assays in low-income countries, particularly in ethnically diverse populations with variable exposure to local endemic infectious diseases.

Pre- and Post-treatment Serum BAFF Levels and BAFF Gene Polymorphisms in Patients with Graves' Disease.

BACKGROUND: B cell activating factor (BAFF), a crucial factor for B cell survival and differentiation, has been linked to several autoimmune conditions. The aim of this study was to evaluate the association of BAFF gene's polymorphisms with its serum levels and to assess their effect on Graves' disease (GD) susceptibility and presentation. METHODS: Sixty-two GD patients and 152 healthy controls have been enrolled to investigate BAFF rs9514827 (-2841 T/C), rs1041569 (-2701 T/A) and rs9514828 (-871 C/T) gene's polymorphism by PCR-RFLP and serum BAFF level's kinetics under medical treatment by ELISA. RESULTS: Median serum BAFF level at baseline was significantly higher in GD patients (841.7 pg/ml [685.23-1058.32]) comparatively to controls (495.75 pg/ml [383.17-595.7]), p = 7.29 E-25. A ROC curve was used to assess BAFF performances in GD diagnosis and revealed an AUC of 94.9% [0.919-0.979], p = 7.29 E-25. At a cutoff value of 654.9 pg/ml of BAFF at baseline, the sensitivity and the specificity were, respectively, 83.9% and 90.8%. BAFF level was significantly increased in smoking patients (1079.55 pg/ml [875.35-1203]) comparatively to nonsmokers (746.95 pg/ml [643.2-915.7]), p = 3.1 E-5. While -2841 T/C and -2701 T/A genotypes and alleles frequencies were similar between patients and controls, the -871*T allele was significantly more prevalent in patients (0.613) than in controls (0.477); p = .01, OR [95% CI] = 1.73 [1.13-2.65]. The three studied polymorphisms were not associated with serum BAFF level at baseline. CONCLUSION: Serum BAFF level is significantly increased in GD especially in smoking patients. rs9514828 - 871*T allele might be a susceptibility variant for GD.

Comparative study of six SARS-CoV-2 serology assays: Diagnostic performance and antibody dynamics in a cohort of hospitalized patients for moderate to critical COVID-19.

BACKGROUND: To overcome the COVID-19 pandemic, serology assays are needed to identify past and ongoing infections. In this context, we evaluated the diagnostic performance of 6 immunoassays on samples from hospitalized patients for moderate to critical COVID-19. METHODS: 701 serum samples obtained from 443 COVID-19 patients (G1: 356 positive RT-PCR patients and G2: 87 negative RT-PCR cases) and 108 pre-pandemic sera from blood donors were tested with 6 commercial immunoassays: (1) Elecsys Anti-SARS-CoV-2, Roche (Nucleocapsid, N), (2) Elecsys Anti-SARS-CoV-2 S, Roche (Spike, S), (3) Vidas SARS-COV-2 IgM/IgG, BioMérieux (S), (4) SARS-CoV-2 IgG, Abbott (N), (5) Access SARS-CoV-2 IgG, Beckman Coulter (Receptor Binding Domain), and (6) Standard F COVID-19 IgM/IgG Combo FIA, SD Biosensor (N). RESULTS: Global sensitivities of the evaluated assays were as follows: (1) Roche anti-N = 74.5% [69.6-79.3], (2) Roche anti-S = 92.7% [84.7-100], (3) Vidas IgM = 74.9% [68.6-81.2], (4) Vidas IgG = 73.9% [67.6-80.1], (5) Abbott = 78.6% [63.4-93.8], (6) Beckman Coulter = 74.5% [62-86.9], (7) SD Biosensor IgM = 73.1% [61-85.1], and (8) SD Biosensor IgG = 76.9% [65.4-88.4]. Sensitivities increased gradually from week 1 to week 3 as follow: (1) Roche anti-N: 63.3%, 81% and 82.1%; (2) Vidas IgM: 68.2%, 83.2% and 85.9%; and (3) Vidas IgG: 66.7%, 79.1% and 86.6%. All immunoassays showed a specificity of 100%. Seropositivity was significantly associated with a higher frequency of critical COVID-19 (50.8% vs. 38.2%), p = 0.018, OR [95% CI] = 1.668 [1.09-2.553]. Inversely, death occurred more frequently in seronegative patients (28.7% vs. 13.6%), p=3.02 E-4, OR [95% CI] = 0.392 [0.233-0.658]. CONCLUSION: Evaluated serology assays exhibited good sensitivities and excellent specificities. Sensitivities increased gradually after symptoms onset. Even if seropositivity is more frequent in patients with critical COVID-19, it may predict a recovery outcome.

Immunogenicity of antitumor necrosis factor therapy in patients with spondyloarthritis.

Objectives To evaluate the serum dosage of the biomedicine (DBM) and the incidence of antidrug antibody (ADA) against antitumor necrosis factor (TNF) in spondyloarthritis, and to demonstrate the influence of these parameters on the clinical efficiency. Methods We conducted a cross-sectional multicentric study including patients with spondylarthritis (SpA) under antiTNF (infliximab [INF], etanercept [ETA] and adalimumab [ADL]) for at least 6 months. A dosage of the ADA and DBM were practiced by the immuno-enzymatic essay. Result Seventy one patients were recruited. Disease modifying antirheumatic drugs (DMARDs) were associated with anti-TNF in 30%. ADA was positive in 54% for INF, 33% for ADL and 0% for ETA with a significant difference(p<0.0001). Immunogenicity was correlated to a bad therapeutic response (Bath Ankylosing Spondylitis Disease Activity Index [BASDAI]≥4)(p=0.04). The DBM was inversely correlated with the rate of ADA for patients treated with INF(p<0.0001) and ADL(p<0.0001). The DBM was also inversely correlated with BASDAI of INF(p=0.03) and ADL (p=0.01). ADA was significantly associated with an anterior switch of anti TNF(p=0.04), the use of INF(p=0.002), presence of coxitis(p=0.01) and higher body mass index (BMI)(p=0.007). DMARDs associated with anti TNF were not a protective factor for positive ADA. In a multivariate study, only INF and BMI were independent factors of positive ADA. Conclusion The ADA formation lowered the DBM and favored the therapeutic failure.

PLA2R antibody, PLA2R rs4664308 polymorphism and PLA2R mRNA levels in Tunisian patients with primary membranous nephritis.

BACKGROUND: Primary membranous nephritis (PMN) is an autoimmune disease induced by the deposit of antibodies (Ab) to the phospholipase receptor A2 receptor (PLA2R) on podocytes. In this context, we aimed to assess the relationships between anti-PLA2R Ab, PLA2R rs4664308 SNP, PLA2R mRNA levels and PMN susceptibility and outcome. METHODS: Sixty-eight PMN patients, 30 systemic lupus erythematosus (SLE) patients with secondary MN and 30 healthy control subjects served for anti-PLA2R Ab measurement by ELISA and PLA2R rs4664308 SNP genotyping by a commercial real-time PCR. Twenty patients with tubulo-interstitial nephritis (TIN) were used as controls for renal PLA2R mRNA quantification in PMN patients from kidney biopsies. PLA2R mRNA quantification was carried-out by real-time PCR after RNA extraction. RESULTS: Forty-three (63.2%) PMN patients received initial therapy consisting of alternating monthly cycles of corticosteroids and cyclophosphamide. Twelve (17.6%) patients had resistant PMN to initial therapy and were consecutively treated by cyclosporine or tacrolimus. Anti-PLA2R Ab were positive in 54 (79.4%) PMN patients, while all SLE patients and controls were negative, p<0.0001. Moreover, anti-PLA2R Ab levels were significantly higher in PMN patients (134.85 [41.25-256.97] RU/ml) than in SLE patients (3.35 [2.3-4.35] RU/ml) and controls (2 [2-2.3]), p<0.0001. Consequently, a ROC curve showed for 100% specificity a sensitivity of 94.1% at a threshold of 2.6 RU/ml. Besides, Anti-PLA2R antibodies levels were significantly associated to non-remission; p = 0.002. The rs4664308*A wild-type allele was significantly more frequent in PMN patients (0.809) than in controls (0.633) and SLE patients (0.65); p = 0.008, OR [95% CI] = 2.44 [1.24-4.82] and p = 0.016, OR [95% CI] = 2.27 [1.15-4.5], respectively. Renal PLA2R mRNA levels were significantly higher in PMN patients (218.29 [66.05-486.07]) than in TIN patients (22.09 [13.62-43.34]), p<0.0001. Moreover, PLA2R mRNA levels were significantly higher in non-remission patients (fold-factor vs. partial remission = 2.46 and fold-factor vs. complete remission = 12.25); p = 1.56 10E-8. In addition, PLA2R mRNA and anti-PLA2R Ab levels were significantly correlated, Spearman Rho = 0.958, p<0.0001. CONCLUSION: Anti-PLA2R Ab and renal PLA2R mRNA could be useful markers for PMN outcome predicting. The PLA2R rs6446308 SNP is associated with PMN susceptibility in Tunisians.

[Comparison of two kits of anti-infliximab antibodies plasmatic measurement]. / Comparaison de deux réactifs de dosage plasmatique des anticorps anti-infliximab.

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 r2 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.

Association of Autoantibody to Rods and Rings with Hepatitis C Outcome and Viral Load.

Despite the current availability of more potent drugs, hepatitis C virus (HCV) infection is still treated with a combination of IFN-α and ribavirin in many countries. Interferon/ribavirin therapy can induce the appearance of autoantibodies to Rods and Rings (anti-RR), which have been associated to a poorer prognosis. The aim of this study was to investigate the prevalence of anti-RR antibodies before and after ribavirin therapy and to look for a possible association with HCV infection outcome. In this context, anti-RR antibodies were detected by IFI on HEp-2 cells in 142 patients under ribavirin therapy (G1: 74 patients with a positive posttreatment HCV-PCR and G2: 68 patients with a negative posttreatment HCV-PCR, matched in age and gender), 84 kidney transplant recipients (KTRs) under mycophenolate and 158 controls (30 with systemic lupus erythematosus, 37 with rheumatoid arthritis, and 91 healthy blood donors). No patient had anti-RR antibody before IFN-α/ribavirin therapy, while 27 (19%) developed the anti-RR pattern under treatment. The anti-RR antibody was absent in all KTRs and the 158 controls. The frequency of anti-RR antibody was significantly higher in G1 (27; 36.48%) than in G2 (0), p < 0.001. Moreover, and in G1, anti-RR antibody was more frequent in nonresponders (NR) patients (23, 56.1%) than in relapsers (REL) (4, 12.1%); p < 0.001, OR [95%CI] = 9.26 [2.75-31.18]. Moreover, anti-RR antibody titer was significantly higher in NR patients (3,200 [1,600-6,400]) comparatively to REL patients (800 [500-1,400]), p = 0.002. Likewise, log of viral load postribavirin therapy was significantly higher in anti-RR positive patients (6.24 ± 0.64) than in anti-RR negative (4.69 ± 1.06), p < 0.001. Based on these findings, ribavirin-induced anti-RR autoantibody seems to be associated with a more frequent nonresponse to IFN-α/ribavirin therapy with a significant higher HCV viral load.

Response to clopidogrel and of the cytochrome CYP2C19 gene polymorphism.

INTRODUCTION: Clopidogrel (clopi) is a prodrug widely prescribed in the management of coronary artery disease and requires the intervention of hepatic cytochrome P450 2C19 (CYP2C19) for its activation. However, there is interindividual variability in response to clopi despite the use of recommended doses. Thus, the studies have highlighted the effect of the CYP2C19 gene polymorphism or Cyp2C19 gene on the response to clopi and particularly Cyp2C19 * 2 which may be associated with an increased risk of major cardiovascular events or MACE. OBJECTIVE: To evaluate the effect of Cyp2C19 * 2 polymorphism on MACE occurrence and hemorrhagic complications in patients treated with clopi. METHODS: We carried out a descriptive longitudinal study including 71 patients placed under clopi for a minimum duration of one month. Genotyping of the Cyp2C19 allele was performed by conventional polymerase chain reaction (PCR). After a follow-up period of 495 ± 183 days, we performed a statistical analysis to evaluate the association between the Cyp2C19 * 2 polymorphism and the occurrence of MACE or hemorrhagic complications. RESULTS: Among our patients, 51% had an angioplasty, 42% medical treatment and 7% a coronary artery bypass surgery. In our study population, 52% were heterozygous (HTZ), 28% homozygous (HMZ) healthy * 1 / * 1 and 20% HMZ had the loss of function allele * 2 / * 2. The allelic frequency of Cyp2C19 * 2 was 46%. Follow-up mean duration was of 495 ± 183 days. During this period, the prevalence of MACE was 11% and that of hemorrhagic complications was 13%. In our study, we did not observe a significant association between the occurrence of MACE or hemorrhagic complications with the genotype carrying the Cyp2C19 * 2 allele. CONCLUSION: Among patients treated with clopi, wearing a Cyp2C19 * 2 function loss allele didn't seem to be associated with a significantly higher risk of MACE, nor a significantly lower risk of hemorragic complications. This suggests the necessity of larger studies.

The role of IL-23/IL-17 axis in human kidney allograft rejection.

Th17 cell subset has been implicated in autoimmune diseases, tumor immunity and, transplant rejection. In order to investigate the role of IL-17/IL-23 pathway in allograft outcome, intragraft expression of IL-17 mRNA and single nucleotide polymorphisms (SNPs) of IL-17A, IL-17F, IL-17RC, and IL23R genes were evaluated with a quantification of IL-17A, IL-17F, and IL-23 plasma levels. This study revealed that recipients with acute rejection (AR) had a significant increase in IL-17A mRNA expression levels after transplantation compared to controls (P = 0.037). Moreover, IL-17A plasma levels were significantly higher in AR group; pretransplantation (Day-1 [D-1]): P = 0.00022 and posttransplantation (Day 7 [D7]): P < 10-14 . IL-17F and IL-23 plasma levels were significantly higher in AR at D7 only (47.86 vs. 22.99 pg/ml; and 33.82 vs. 18.811 pg/ml; P = 0.015 and P < 10-17 , respectively). Using receiver-operating characteristic curves, D7 IL-17A and IL-23 plasma levels exhibited excellent sensitivities and specificities for predicting AR. Genetic study revealed no association between IL-17A, IL-17F, IL-17RC, and IL23R studied SNPs and AR. Nevertheless, a significant improvement of graft survival was found in kidney transplant recipients carrying IL-17F-rs763780*A/A, IL-17RC*G/G, and *G/A genotypes. Besides, IL-17A mRNA levels were significantly higher in patients carrying the IL-23R*G/G genotype comparatively to those with *G/A genotype. Based on these findings, significant increase of IL-17A mRNA and protein levels in AR recipients that are genetically controlled highlights the role of this cytokine that can be a useful clinical biomarker to predict early acute renal allograft rejection.

IL-17A, IL-17RC polymorphisms and IL17 plasma levels in Tunisian patients with rheumatoid arthritis.

BACKGROUND: Interleukin-17 (IL-17), a cytokine mainly secreted by Th17 cells, seems to play a significant role in the pathogenesis of rheumatoid arthritis (RA). Functional genetic polymorphisms in IL-17 and its receptor genes can influence either qualitatively or quantitatively their functions. Therefore, we aimed to study the impact of IL17-A and IL17RC polymorphisms on plasma level of IL-17 and RA susceptibility and severity. METHODS: In this context, IL-17A*rs2275913 and IL-17RC*rs708567 polymorphisms were investigated together with the quantification of IL17 plasma level in 115 RA patients and 91 healthy control subjects matched in age, sex and ethnic origin. RESULTS: There were no statistically significant associations between IL-17A and IL-17RC studied polymorphisms and RA susceptibility. In contrast, IL-17A plasma levels were significantly higher in patients (55.07 pg/ml) comparatively to controls (4.75 pg/ml), p<10E-12. A ROC curve was used to evaluate the performance of plasma IL-17 in detecting RA. Given 100% specificity, the highest sensitivity of plasma IL-17A was 61.7% at a cut-off value of 18.25 pg/ml; p < 10E-21, CI = [0.849-0.939]. Analytic results showed that the IgM-rheumatoid factor and anti-CCP antibodies were significantly less frequent in patients with the IL-17RC*A/A genotype than those carrying *G/G and *G/A genotypes; p = 0.013 and p = 0.015, respectively. Otherwise, IL-17 plasma levels' analysis showed a significant association with the activity of RA (DAS28≥5.1 = 74.71 pg/ml vs. DAS28<5.1 = 11.96 pg/ml), p<10E-6. CONCLUSION: IL-17A*rs2275913 (G/A) and IL-17RC*rs708567 (G/A) polymorphisms did not seem to influence RA susceptibility in Tunisian population. This result agrees with those reported previously. Plasma IL-17A level seems to be predictive of severe RA occurrence.

Urinary mRNA analysis of biomarkers to epithelial mesenchymal transition of renal allograft.

Renal allograft loss is most often a chronic process, irrespective of the mechanism at stake. In this prospective study, we studied the expression of epithelial to mesenchymal transition (EMT) markers vimentin and ß-catenin by immunohistochemistry in the surveillance biopsy and measured the mRNA encoding vimentin (VIM), CD45, GAPDH and uroplakin 1a (UPK) by quantitative PCR in urinary cells in 75 renal transplant patients. The aim is to establish a simple screening test for chronic renal allograft dysfunction. We found that the value of the mRNA of vimentin and CD45 relative to the uroplakin 1a (UPK) mRNA is correlated with the score in vimentin immunostaining in routine biopsies. These biomarkers could be used as a noninvasive tool to monitor the renal graft fibrogenesis. This test could be used for early detection of fibrotic diseases of the kidney transplant.

Complement Component C3 Variant (R102G) and the Risk of Neovascular Age-Related Macular Degeneration in a Tunisian Population.

Purpose To explore the association between the polymorphism (S/F) p.R102G in the complement component 3 (C3) gene and age-related macular degeneration (AMD) in a Tunisian population. Methods The molecular study was performed by polymerase chain reaction using sequence-specific primers (PCR-SSP) in 207 control subjects free of any eye disease (fundus normal) and 145 patients with exudative AMD. The CH50 activity and quantification of C3 and C4 have been made by technical home method and nephelometry, respectively. Results The prevalence of C3 GG genotype polymorphism was significantly higher in AMD patients compared to controls (OR: 2.41, IC 95% [1.90-3.05], p = 0.0007). However, no correlation was found between this allelic variant and the type of neovascularization. Similarly, there is no association between this polymorphism and the presence of functional and/or quantitative hypocomplementemia. Conclusions The C3 GG genotype of the gene could be a susceptibility factor for AMD in the Tunisian population. However, it does not seem to influence the clinical profile of the disease.

Computer-Assisted Classification Patterns in Autoimmune Diagnostics: The AIDA Project.

Antinuclear antibodies (ANAs) are significant biomarkers in the diagnosis of autoimmune diseases in humans, done by mean of Indirect ImmunoFluorescence (IIF) method, and performed by analyzing patterns and fluorescence intensity. This paper introduces the AIDA Project (autoimmunity: diagnosis assisted by computer) developed in the framework of an Italy-Tunisia cross-border cooperation and its preliminary results. A database of interpreted IIF images is being collected through the exchange of images and double reporting and a Gold Standard database, containing around 1000 double reported images, has been settled. The Gold Standard database is used for optimization of a CAD (Computer Aided Detection) solution and for the assessment of its added value, in order to be applied along with an Immunologist as a second Reader in detection of autoantibodies. This CAD system is able to identify on IIF images the fluorescence intensity and the fluorescence pattern. Preliminary results show that CAD, used as second Reader, appeared to perform better than Junior Immunologists and hence may significantly improve their efficacy; compared with two Junior Immunologists, the CAD system showed higher Intensity Accuracy (85,5% versus 66,0% and 66,0%), higher Patterns Accuracy (79,3% versus 48,0% and 66,2%), and higher Mean Class Accuracy (79,4% versus 56,7% and 64.2%).

Prediction of T Cell Epitopes from Leishmania major Potentially Excreted/Secreted Proteins Inducing Granzyme B Production.

Leishmania-specific cytotoxic T cell response is part of the acquired immune response developed against the parasite and contributes to resistance to reinfection. Herein, we have used an immune-informatic approach for the identification, among Leishmania major potentially excreted/secreted proteins previously described, those generating peptides that could be targeted by the cytotoxic immune response. Seventy-eight nonameric peptides that are predicted to be loaded by HLA-A*0201 molecule were generated and their binding capacity to HLA-A2 was evaluated. These peptides were grouped into 20 pools and their immunogenicity was evaluated by in vitro stimulation of peripheral blood mononuclear cells from HLA-A2+-immune individuals with a history of zoonotic cutaneous leishmaniasis. Six peptides were identified according to their ability to elicit production of granzyme B. Furthermore, among these peptides 3 showed highest affinity to HLA-A*0201, one derived from an elongation factor 1-alpha and two from an unknown protein. These proteins could constitute potential vaccine candidates against leishmaniasis.

Natural evolution of hepatitis C virus infection in hemodialysis Tunisian patients and CTLA-4 SNP's.

AIM: To analyze the polymorphisms of CTLA-4 gene involved in the response against hepatitis C virus (HCV) infection. METHODS: We recruited 500 hemodialysed patients from several hemodialysis centers, all HCV-antibody positive, spread over different regions of Tunisia, as part of a national survey in 2008 conducted in the laboratory of immunology at the Charles Nicolle hospital Tunisia, classified into two groups G1 (PCR+) and G2 (PCR-) according to the presence or absence of viral RNA. Of these patients, 307 were followed prospectively on a viral molecular level over a period from 2002 to 2008, divided into two groups based on the persistence and viral clearance. PCR-RFLP was performed for the analysis of SNPs (+49) A/G and (+6230) G/A CTLA-4 for these 500 patients and 358 healthy controls. RESULTS: Analysis of clinical and virological characteristics of our cohort suggests a nosocomial infection in our hemodialysed patients with transfusion history as a primary risk factor and a predominance of genotype 1b. The haplotype analysis revealed an increase of frequencies of GG (+49)/(CT60) CTLA-4 in the entire patients group compared to controls (P = 0.0036 and OR = 1.42; 95%CI: 1.12-1.79, respectively). This haplotype is therefore associated with susceptibility to HCV infection. CONCLUSION: Our study suggests a possible role of CTLA-4 polymorphisms in the outcome of HCV infection in the Tunisian hemodialysed population.

[The epithelial-mesenchymal transition and fibrosis of the renal transplant]. / La transition épithélio-mésenchymateuse et la fibrose du transplant rénal.

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.

Vascular endothelial growth factor genetic polymorphisms and susceptibility to age-related macular degeneration in Tunisian population.

PURPOSE: Three VEGF SNPs (-2578) C/A, (+405) G/C and (+936) C/T were investigated in Tunisian exudative AMD patients in order to determine their association with the disease susceptibility and their influence to intravitreal bevacizumab therapy response. METHODS: 145 AMD patients and 207 age-matched controls were included. 68 patients were treated with intravitreal bevacizumab. SNPs genotyping were performed using direct sequencing. The serum VEGF was assayed by ELISA (R&D). RESULTS: The (+405) CC and (+936) TT genotypes were higher in AMD patients than in controls (p = 5 × 10(-6) and p = 0.021, respectively). The mean plasma levels of VEGF were statistically higher in AMD patients (84.22 pg/ml) than in controls (15 pg/ml). Three months after bevacizumab treatment, 52 patients (85.6%) were classified as good responders (GR) and 16 (14.4%) as poor responders (PR). The mean plasmatic-VEGF levels in GR patients was higher (86.61 ± 80.30 pg/ml) than in PR patients (47.12 ± 45.74 pg/ml) (p = 0.086). The patients with genotype homozygous TT (+936) would be PR compared to those carrying CT and CC genotypes. Whereas, those with AA (-2578) genotype would be GR compared with others genotypes (p = 0.014; p = 0.042 respectively). CONCLUSIONS: Our results show that VEGF genetic variants may contribute to the susceptibility to neovascular AMD in Tunisian patients.

New C1q mutation in a Tunisian family.

Hereditary C1q deficiency (C1qD) is the most penetrant genetic factor predisposing to the development of lupus pathology with more than 93% of C1q deficient patients developing this autoimmune pathology throughout their life. It is a rare autosomal recessive deficiency, with only 67 cases reported so far including one Tunisian girl who died at the age of three from complications resulting from severe systemic lupus erythematosus. Although C1qD was confirmed in the serum of this patient using C1q ELISA and classical pathway specific functional assays, no DNA sample had been obtained from this patient. Here we report the analysis of sera and DNA of members of this patient's closer family. Our analysis identified a homozygous mutation within the gene encoding the C-chain of C1q leading to a deficiency of C1q in an older sister of our original patient. This mutation, termed g.5580G4C, represents a single basepair substitution in exon 1 of the C1q C chain gene which changes the codon of Gly61 to Arg 61. Amongst the other 14 mutations leading to C1qD, g.5580G4C represents the first reported transversion leading to human C1qD.