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Since Fc-gamma receptors (FcgRs) are involved in the degradation of IgG complexes, we assessed whether a modification in FcgRs' affinity to Fc portion, caused by single nucleotide polymorphisms such as rs1801274-R131H FcgRIIa, rs396991-F158V FcgRIIIa and NA1/NA2-FcgRIIIb, might impact clearance of therapeutic monoclonal antibodies and thus, serum drug levels and the development of anti-drug antibodies.A cross sectional, multicentral and non-interventional study was conducted in Tunisian RA patients treated with rituximab (RTX), etanercept (ETA), infliximab (IFX) and adalimumab (ADL). Serum drug level (SDL) of the different biologics and ADA against them were measured. All patients were genotyped for the three FCGR SNPs.A total of 81 patients were included: 47 were under TNF-inhibitors (18 ETA, 13 ADL and 16 IFX) and 34 were under RTX. Regardless of the type of biotherapy, SDL was in therapeutic range, in 35 patients (43.2%) of whom only one was treated with RTX. Fourteen patients (22.2%) developed ADA but none of the patients treated with ETA had detectable ADA levels. There was no association between SDL positivity and FCGR polymorphisms. However, the high affinity FCGR2A 131 H/H receptor was statistically more prevalent in patients with detectable ADA treated with ADL, IFX and RTX (p=0.018). The same result was obtained in mAb TNFi subgroup (n=29, p=0.022) as well as in patients treated only with IFX (n=16, p=0.029).Our work supports the hypothesis of an impact of FCGR SNPs on biologics' immunogenicity, particularly FCGR R131H polymorphism, but further studies with larger cohorts needs to be undertaken to confirm these results.

Interferon-beta, the most widely prescribed medication for multiple sclerosis, is generally considered safe. Nevertheless, rarely serious and/or life-threatening side effects have been reported such as thrombotic microangiopathy. A few mechanisms have been proposed to explain how interferon causes thrombotic microangiopathy, but insufficient immunological studies have been unable to pin this phenomenon down to a single pathophysiologic pathway. We report thrombotic microangiopathy due to acquired complement factor I deficiency in a male receiving interferon-beta treatment for multiple sclerosis. After three years of starting the therapy, the 28-year-old patient presented with malignant hypertension causing seizures, rapidly progressive renal failure requiring hemodialysis, and hemolytic anemia. Corticosteroid and plasma exchange sessions permitted hemolysis control. Nonetheless, the patient remained hemodialysis-dependent. Exploration of the complement system found a complement factor I deficiency whose activity normalized at the control carried out after two years. We concluded that IFNβ treatment may cause complement factor I deficit, which can lead to thrombotic microangiopathy and severe renal failure.

International audience; A coplanar tri-band wearable antenna combined with an electromagnetic bandgap (EBG) structure is described for sub-6 GHz 5G and wireless local area network (WLAN) applications. The proposed antenna is fully implemented in textile materials thus offering a robust, compact, and discreet solution to meet the requirements of wearable applications. The addition of the EBG structure increases the textile antenna performance in terms of radiation patterns in the presence of the human body. The experimental results show that the proposed design exhibits tolerance to various bending conditions as well as loading by body tissues. In addition, to ensure the safety of the design for human health, the values of the specific absorption rate (SAR) have been reduced by more than 95%, which complies with the international standard. This design could thus be considered as a good candidate for IoT applications compared to the current state of the art while having a tri-band behavior and smaller volume.

SummaryCoronavirus disease 2019 (COVID-19) expresses a wide spectrum of disease severity. We investigated the profile of IgG and IgG subclass antibody responses to SARS– CoV-2 in Tunisian patients with COVID-19 according to disease severity (86 patients with severe disease and 63 with mild to moderate disease). Two in house developed ELISA with excellent performance were used to test for antibodies to the nucleocapsid (N) protein and the receptor-binding domain of the spike antigen (S-RBD) of SARS-CoV-2. IgG, IgG1 and IgG3 antibodies were significantly higher in patients with severe disease compared to non-severe disease. Antibodies to S-RBD or the N protein were dominated by IgG1 and IgG3 or IgG1/IgG3 and IgG2 subclasses respectively. In patients with severe disease, IgG antibodies ‘ appearance to S-RBD was delayed compared to the N protein. IgG subclass imbalance may reflect the pathophysiology of COVID-19 and may herald disease aggravation. This study brings information on the immune responses to SARS-CoV-2 in North African patients and completes the picture drawn on COVID-19 in different African populations and worldwide.

Axial spondyloarthritis (SpA) is a common inflammatory arthritis characterized by axial skeletal inflammation, enthesitis, and association with HLA-B27. Pro-inflammatory cytokines play important roles in the regulation of inflammatory response and seem to be good candidates involved in the development of this pathology.To assess the influence of the functional polymorphisms of single nucleotide polymorphims (SNPs) of IL-1 and IL-1 Ra in SpA susceptibility Tunisian patients.One hundred and one patients and 100 ethnic-matched healthy controls were genotyped. Susceptibility to SpA was showed with SNP's: C/T of IL-1α (-889) (p=0.0001) and 1/1 of IL-1Ra (p10-3). Analysis of SpA patients according to clinical behavior of the disease reveled the influence of these polymorphisms in SpA course. Indeed, individuals carrying the allele T (+3954) of IL-1β and allele 1 of IL-1Ra had an increased risk of peripheral arthritis (p=0.047, p=0.05, respectively). Also the 1/1 genotype of IL-1Ra was significantly decreased in SpA patients having an active disease (BASDAI4) (p=0.033).Genetic polymorphisms of pro-inflammatory IL-1/IL-1Ra cytokines seem to be involved in susceptibility and clinical course of SpA in Tunisian patients.

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 Conclusion The ADA formation lowered the DBM and favored the therapeutic failure.

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.

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. Study showing significant associations between Day 7 plasma IL-17A, IL-17F and IL-23 and AR with good performances for IL-17A and IL-23 in predicting acute rejection (AR) occurrence; significant increase of IL-17A expression in kidney graft in case of AR; a significant improvement of graft survival in recipients carrying IL-17F-rs763780*A/A, IL-17RC*G/G and *G/A genotypes.

International audience; This paper describes the antenna performances made from common clothing fabrics for 5G and Internet of Things (IoT) applications by employing electromagnetic bandgap (EBG) structures as the substrate of the antenna for gain enhancement in millimeter-wave frequency. A suspended transmission line method has been taken into account for characterization of EBG structure to obtain the optimum design. Furthermore, the optimum unit cell, which is loaded onto the antenna, is easy to implement and allows obtaining a Peak Gain of 9.79 dBi in 26 GHz band.

This paper presents a novel dual-band wearable antenna using textile materials. The proposed antenna is designed for WLAN applications operation on 2.45 and 5.8 GHz. Due to the use of this structure near the human body, we applied different techniques of miniaturization. The proposed design must respect mains antenna parameters with the presence of the human body. To achieve the fixed goal, we used in this paper an Artificial Magnetic Conductor (AMC) structure. The configuration of the AMC-integrated antenna is low profile with a thickness of 6.19 mm and compact with the area of 48×72 mm2. The proposed antenna presents very interesting results which can be shown in simulation results.

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.

Background Fc gamma receptors (FcgR) type IIA IIIA and IIIB play an important role in the recognition of immune complexes (ICs) by binding their Ig-Fc portion. However, it has been demonstrated that FcgR single nucleotide polymorphisms (SNP) leads to low binding affinity alleles (FcgRIIA-131R, IIIA-158V and IIIB NA2). Therefore, we can make an assumption that the presence of these risk alleles could influence the outcome of immune mediated disease such as rheumatoid arthritis (RA). Objectives The aim of this study was to assess the relationship between functional SNP of FcgR IIA H13R, IIIA V158F and IIIB NA1/NA2 and disease severity scores in RA. Methods We assessed disease severity in RA patients based on the Health Assessment Questionnaire (HAQ) and Sharp/van der Heijde (mSharp) method. To reduce selection biais, all recruited patients were treated with conventional DMARDs.We considered patients with HAQ score ranged from 2 to 3 as having severe disability. For radiographic evaluation, since there is not validated threshold for joint damage severity, we took mSharp score median value of our population as a reference. Patients underwent FcgRIIA, FcgRIIIA and FcgRIIIB SNP study using PCR-SSP and direct sequencing process. Then, biallelic polymorphisms were examined for association with HAQ and mSharp score. Results Fifty-eight RA patients were enrolled. The mean duration of the disease was 11.77 years [0.5-24]. Among these patients, 34 (58.62%) had severe disability according to HAQ score. The mSharp median value was 43,5 [0-232] and 28 (48.28%) patients had a score above this value. Genotypic study showed that FcgR IIIB-NA2 was significantly associated with severe disability (p=0.021) (Table 1). Furthermore, FcgRIIIA-158F and IIA-131R carriers were more frequent in patients with severe disability but the association was not statistically significant. Finally, no correlation was found between radiographic evaluation and FcgR SNP study (table 2). Conclusion FcgR low affinity alleles seem to confer susceptibility to severe functional impairment in RA but not to structural damage. However further studies on larger population must be done to corroborate these findings. References [1] Brun JG, Madland TM, Vedeler CA. Immunoglobulin G Fc-receptor (FcgammaR) IIA, IIIA, and IIIB polymorphisms related to disease severity in rheumatoid arthritis. J Rheumatol. 2002;29:1135–40. [2] Kastbom A, Ahmadi A, Soderkvist P, Skogh T. The 158V polymorphism of Fc gamma receptor type IIIA in early rheumatoid arthritis: increased susceptibility and severity in male patients (the Swedish TIRA project) Rheumatology (Oxford)2005;44:1294–8. [3] Lee YH, Bae SC, Song GG. FCGR2A, FCGR3A, FCGR3B polymorphisms and susceptibility to rheumatoid arthritis: a meta-analysis.Clin Exp Rheumatol. 2015 Sep-Oct; 33 (5):647-54. Disclosure of Interests None declared

Background Rheumatoid arthritis (RA)’s prognosis drastically improved with the introduction of TNF-blockers. However, reasons behind therapeutic failure in some patients remain unclear. Several factors might influence pharmacokinetics of these drugs by reducing their half-life and, consequently, their effectiveness. Considering Fc-containing biologics like infliximab (IFX) and adalimumab (ADL), Fc gamma receptors (FcgRs) polymorphism would be an interesting genetic candidate to focus on. Objectives The aim of our study was to determine the influence of low affinity allele FcgRIIA-131R on ADL and IFX bioavailability. Methods We enrolled RA patients treated with IFX and ADL for over six months. Blood samples were collected for each patient immediately prior to drug administration. Quantitative measurements of the residual drug concentration (DC) was carried out by a commercial enzyme-linked immunosorbent assay (ELISA) kit (Promonitor®). Then, we identified patients with DC above therapeutic cut-off (DC+) for each biologic. EULAR criteria were considered to determine treatment outcome. FcgRIIA H131R polymorphism was genotyped using PCR-SSP. Results Twenty-nine patients were included (13 treated with ADL and 16 with IFX). We identified 31.3% and 23.1% non-responders among patients treated with IFX and ADL respectively. Patients with DC+ were more frequent in ADL group (76.9%) than IFX group (43.75%). For IFX, DC+ was significantly correlated with the presence of FcgRIIA 131-R (p=0.033). In fact, none of the HH-genotyped patients had DC+. Furthermore, an association between FcgRIIA 131-R allele and poor response to IFX was noted (p=0.059) while all HH-genotyped patients responded to IFX. For ADL, no correlation was found with both of residual DC and response to treatment. Conclusion The presence of FcgIIA-131 R allele might be a predictive factor of non-responsiveness to TNF-blockers. It also appears to be associated to a higher residual DC. That might be explained by a reduced biologic clearance due to a lower binding affinity to Fc portion compared to wild allele FcgRIIA-131H. Therefore, FcgR polymorphism assessment in RA patients would be a decision-making parameter to consider, as part of the personalized medicine approach. References [1] Montes A, Perez-Pampin E, Narvaez J, et al. Association of FCGR2A with the response to infliximab treatment of patients with rheumatoid arthritis. Pharmacogenet Genomics. 2014;24(5):238-245 [2] DavilaaFajardo CL, van der Straaten T, Baak-Pablo R, et al. FcGR genetic polymorphisms and the response to adalimumab in patients with rheumatoid arthritis. Pharmacogenomics. 2015;16(4):373-381 [3] Canete JD, Suarez B, Hernandez MV, et al. Influence of variants of Fc gamma receptors IIA and IIIA on the American College of Rheumatology and European League Against Rheumatism responses to anti-tumour necrosis factor alpha therapy in rheumatoid arthritis. Ann Rheum Dis. 2009;68(10):1547-1552. Disclosure of Interests None declared

Background Even though biologics have been used for several years in treatment of rheumatoid arthritis (RA), little is known about factors that modify their pharmacokinetics and therefore their efficacy. Polymorphisms (SNPs) in receptors for constant region Fc of IgG (FcgR) might influence the therapeutic outcome of molecules that incorporate an Fc fragment in their structure such as etanercept (ETA), adalimumab (ADL) infliximab (IFX) and rituximab (RTX). Objectives The aim of our study was to determine whether the presence of low affinity allele of FcgR (FcgRIIA-131R, FcgRIIIA-158F and FcgRIIIB-NA2) influences efficiency and immunogenicity of ETA, ADL, IFX and RTX in RA Tunisian patients. Methods We included RA patients treated with biologics for at least six months. Response to treatment was assessed according to EULAR criteria. Quantitative measurement of antidrug antibodies (ADAb) for each biologic agent was carried out by a commercial enzyme-linked immunosorbent assay (ELISA) kit (Promonitor®). To do so, blood samples were collected for each patient right before drug administration. FcgRIIA, FcgRIIIA and FcgRIIIB SNPs was genotyped for all patients using PCR-SSP and direct sequencing process. Results Seventy-nine RA patients treated with biologics were enrolled (18 with ETA,13 with ADL,16 with IFX and 32 with RTX). Regardless of biologic type, 61 patients (77.2%) responded to treatment and 14 patients (17.7%) developed ADAb. Genotypic study revealed a correlation between poor response to treatment and the presence of at least one FcgRIIA 131-R allele (94.7% for RH/RR genotypes versus 5.3% for H/H genotype). But, the difference was not statistically significant (p=0.25). Besides, this mutant allele was significantly associated to the presence of ADAb (71.4% of ADAb positivity for RH/RR genotypes versus 28.6% for H/H genotype: p=0.041). The haplotypic study shows that the risk allele combination of FcgR IIA-131R/IIIA-158F/IIIB-NA2 was more frequent in ADAb+ (27%) compared to ADAb- subjects (23%) and in non-responders (27%) versus good responders (23%). But, neither of these associations was statically significant. Conclusion Our study suggests that RA patients FcgRIIA-131R allele carriers are more susceptible to develop ADAb than those with HH wild genotype. That could be explained by a higher biologic clearance in H-carrier patients, resulting in a decreased half-life and ultimately a lower risk of ADAb formation. Thus, FcgR polymorphism genotyping may be a useful marker for predicting response to Fc-containing biologics in Tunisian RA patients. Further studies need to be done on larger population. References [1] Romero-Cara P, Torres-Moreno D, Pedregosa J, Vilchez JA, Garcia-Simon MS, Ruiz-Merino G, Moran-Sanchez S, Conesa-Zamora P. A FCGR3A Polymorphism Predicts Anti-drug Antibodies in Chronic Inflammatory Bowel Disease Patients Treated With Anti-TNF. Int J Med Sci2018; 15(1):10-15 [2] Lee YH, Bae SC. Associations between PTPRC rs10919563 A/G and FCGR2A R131H polymorphisms and responsiveness to TNF blockers in rheumatoid arthritis: a meta-analysis. Rheumatol Int. 2016Jun;36(6):837-44. [3] Lee YH, Bae SC, Song GG,Functional FCGR3A 158 V/F and IL-6 -174 C/G polymorphisms predict response to biologic therapy in patients with rheumatoid arthritis: a meta-analysis. Rheumatol Int. 2014Oct;34(10):1409-15. Disclosure of Interests None declared

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 ...

We aimed to investigate the prevalence of the JAK2 V617F mutation in Tunisian patients with myeloproliferative neoplasms (MPN) and to look for possible associations with diseases’ presentation. In this context, JAK2 V617F polymorphism was detected by PCR-RFLP and direct sequencing in 213 MPN patients (109 with polycythemia vera (PV), 93 with essential thrombocythemia (ET) and 11 with primary myelofibrosis (PMF)), 77 unclassified patients with thrombosis (UPT) and 95 healthy control subjects. The JAK2 V617F mutant allele was present by either PCR-RFLP or direct sequencing in 158 (74.17%) MPN patients while all UPT and controls were negative. Besides, the JAK2 V617F mutation was significantly more frequent in patients with PV 98 (89.9%) than in ET 54 (58.1%) and PMF 6 (54.5%) groups, p

Background : The Tuberculin skin test (TST) has been used for years in the latent tuberculosis infection (LTBI) diagnosis, but it has, well-documented, low sensitivity and specificity. Interferon-γ release assays (IGRA) has been reported to be more sensitive and specific than TST. Therefore, this study aimed to evaluate the performance of a commercial IGRA, QuantiFERON ® -TB Gold In-Tube (QFT-GIT), comparatively to TST in LTBI diagnosis. Patients and Methods : This study included 238 patients who were candidate for an anti-TNF therapy. The screening for LTBI was performed by both TST and QFT-GIT test for all patients. In order to evaluate the strength of associations, the odds ratios (OR) together with 95% confidence intervals (CI) were calculated. The correlation between QFT-GIT and TST was evaluated using κ statistics. Results : Sixty-three (26.4%) sera were positive for QFT-GIT with a mean level of IFN-γ of about 1.18 IU/ml, while 81 (34%) patients were positive for TST. Agreement between QFT-GIT and TST was poor (37 QFT-GIT+/TST- and 55 QFT-GIT-/TST+), κ=0.09 (SD=0.065). The positivity of QFT-GIT was not influenced by BCG vaccination or by immunosuppression. Nevertheless, it was significantly associated to both history of an earlier tuberculosis disease (HETD) and its radiological sequel (RS), p =6E-7 and p =1E-8, respectively. Inversely, the TST results were not correlated to either HETD or RS, but the TST positivity was less frequent in immunosuppressed patients (45.5% vs. 73.9%), p =1E-5, OR (95% CI) = 0.29 [0.17-0.52]. Moreover, the extent of both the immunosuppression period and the time elapsed from the last BCG injection was significantly correlated to a lesser TST positivity, p =3E-12 and p =5E-7, respectively. Among the QFT-GIT-/TST+ patients (n=55) whom received an anti-TNF agent without any prophylactic treatment of LTBI, no tuberculosis was detected with a median follow-up of 78 weeks [56-109]. Conclusion : Our study suggests that the QFT-GIT has a higher performance comparatively to TST in the LTBI screening that is unaffected by either BCG vaccination or immunosuppression. Therefore, IGRAs has to replace TST especially in patients who are under consideration for an anti-TNF therapy.

BackgroundPrimary 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.MethodsSixty-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.ResultsForty-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, pConclusionAnti-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.

Background:Fc gamma receptors (FcγRs) play a major role in the regulation of humoral immune responses. Single-nucleotide polymorphisms (SNPs) of FCGR2A and FCGR3A and FCGR3B can impact the expression level, IgG affinity and function of the CD32 and CD16 FcγRs in response to their engagement by the Fc fragment of IgG. It was described in patient treated for rheumatoid arthritis (RA), that such a polymorphism may influence patients response to TNF-blockers.Objectives:In this study, we aimed to investigate whether the FCGR2A H131R (rs1801274), FCGR3A F158V (rs396991), and FCGR3B NA1/NA2 polymorphisms can be involved in the genesis of anti-drug-antibody ADAb to anti-TNF therapy in RA patients under etanercept (ETA), adalimumab (ADL) and infliximab (INF).Methods:We included 47 patients treated for RA under TNF-blockers. To assess the association between the FCGR2A H131R (rs1801274), FCGR3A F158V (rs396991), and FCGR3B NA1/NA2 polymorphisms and immunogenicity of TNF-blockers, we used allele contrast, the recessive model, the dominant model, and the homozygote contrast. Quantitative measurements of the ADAbs was carried out by a commercial enzyme-linked immunosorbent assay (ELISA) kit (Promonitor)®after 6 months of treatment.Results:We involved 18 patients treated with ETA, 13 patients with ADL and 16 under INF. None of the patients under ETA has developed ADAb and respectively 1 and 7 patients developed immunogenicity with ADL and INF. We excluded patients under ETA from statistical study since they didn’t develop ADAb.A significant association was revealed between FCGR2A H131R polymorphism and immunogenicity of INF and ADL (table 1).Table 1.Association between FCGR2A polymorphism and immunogenicity to INF and ADLFCGR2A association with ADAb (n=29, crude analysis)GenotypeADAb=0ADAb=1OR (95% CI)P-valueH/H1 (4.8%)3 (37.5%)1.000.031H/R-R/R20 (95.2%)5 (62.5%)0.08 (0.01-0.98)There weren’t significant associations between ADAb’s development and FCGR3A F158V and FCGR3B NA1/NA2 polymorphism.Conclusion:FCGR2A R allele carriers show less susceptibility to develop ADAb to ADL and INF with follow-up times of 6 months. Our results provide an explanation for controversies in the relationships between FCGR2A H131R polymorphism and TNF-blockers response. Further studies with larger population of RA patients should be undertaken to confirm this hypothesis.References:NoneDisclosure of Interests:None declared

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.To evaluate the effect of Cyp2C19 * 2 polymorphism on MACE occurrence and hemorrhagic complications in patients treated with clopi.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.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.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.

Aim The aim of the present study was to characterize the molecular basis of complement factor I deficiency in Tunisian atypical haemolytic and uremic syndrome patients with low factor I levels. Methods Six adults and seven children were enrolled in this study. Complement factor I levels were assessed by a homemade sandwich ELISA and ranged between 12.5% and 60%. Genomic DNA was amplified by way of a polymerase chain reaction using intronic primers flanking the 13 coding exons. Sequencing of amplified products was carried out by the dye terminator sequencing method. Molecular study was performed on parental samples for three dead paediatric patients. The control group consisted of 100 healthy Tunisian donors. Results We identified a total of 13 substitutions and one insertion: seven in introns, four in exons and three in UTR. The new mutations were c.-132G > C, c.71 + 181 T > A in 5'UTR and intron 1, respectively. Three intronic polymorphisms were predicted to have impact on splicing events: c.482 + 6C > T, c.884-42_884-41insTTAAA (rs34422850) and c.1429 + 33 A > G (rs9998151). They were three missense mutations leading to a p.Ile 357Met, p.Ile416Leu and p.GLu548Gln. p.Ile 357Met was found in two patients and one relative. Half of the patients had associated mutation and/or polymorphisms. Conclusion This is the first genetic study in Tunisian and Maghrebin atypical haemolytic and uraemic syndrome patients. The high occurrence of Ile357Met mutation may reflect a founding effect. Functional impact of the two new mutations c.-132G > C and c.71 + 181A > T have to be studied. Association of simultaneous genetic abnormalities may explain the variability of atypical haemolytic and uraemic syndrome, penetrance and disease phenotype.

To analyze the polymorphisms of CTLA-4 gene involved in the response against hepatitis C virus (HCV) infection.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.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.Our study suggests a possible role of CTLA-4 polymorphisms in the outcome of HCV infection in the Tunisian hemodialysed population.

Background : Several automated systems had been developed in order to reduce inter-observer variability in indirect immunofluorescence (IIF) interpretation. We aimed to evaluate the performance of a processing system in antinuclear antibodies (ANA) screening on HEp-2 cells. Patients and Methods : This study included 64 ANA-positive sera and 107 ANA-negative sera that underwent IIF on two commercial kits of HEp-2 cells (BioSystems® and Euroimmun®). IIF results were compared with a novel automated interpretation system, the “ Cyclopus CADImmuno®” (CAD). Results : All ANA-positive sera images were recognized as positive by CAD (sensitivity = 100%), while 17 (15.9%) of the ANA-negative sera images were interpreted as positive (specificity = 84.1%), κ=0.799 (SD=0.045). Comparison of IIF pattern determination between human and CAD system revealed on HEp-2 (BioSystems®), a complete concordance in 6 (9.37%) sera, a partial concordance (sharing of at least 1 pattern) in 42 (65.6%) cases and in 16 (25%) sera the pattern interpretation was discordant. Similarly, on HEp-2 (Euroimmun®) the concordance in pattern interpretation was total in 5 (7.8%) sera, partial in 39 (60.9%) and absent in 20 (31.25%). For both tested HEp-2 cells kits agreement was enhanced for the most common patterns, homogenous, fine speckled and coarse speckled. While there was an issue in identification of nucleolar, dots and nuclear membranous patterns by CAD. Conclusion : Assessment of ANA by IIF on HEp-2 cells using the automated interpretation system, the “ Cyclopus CADImmuno®” is a reliable method for positive/negative differentiation. Continuous integration of IIF images would improve the pattern identification by the CAD.

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.

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.

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 β-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.

Background Genetic polymorphisms of interleukin (IL)-17F, associated with functional and/or quantitative change in this glycoprotein, have been described as predisposing to various autoimmune diseases. The proinflammatory IL-17 has some roles in renal transplantation. In this context, the relationship between the most common IL-17F polymorphisms with acute renal allograft rejection susceptibility in Tunisian renal recipients has been investigated. Methods We examined 93 renal transplant recipients who were enrolled and classified as follows: GI, 48 transplant recipients who developed at least one episode of acute rejection; and GII, 45 controls, kidney recipients who also were followed for at least 1 year and had stable renal function. Single nucleotide polymorphisms (SNPs) of IL-17F gene, including -1507 C/T (rs18889570), 7384 A/G (rs2397084), 7469 C/T (rs11465553), and 7489 A/G (rs763780), were evaluated using direct sequencing. Results No statistically significant association of the IL-17F SNPs studied with the onset of acute rejection was observed. However, AA genotype on 7489A/G SNP showed anti-HLA antibodies less than other genotypes and a higher graft survival time (P = .017). Conclusion The AA genotype on 7489A/G SNP of IL-17F and the A allele might be associated with a lower risk of acute rejection with better graft survival.

This paper presents results of direction of arrival (DOA) estimation using multiple signal classification (MUSIC), Root-MUSIC, and estimation of signal parameters via rotational invariance technique algorithms. As is well known, these algorithms are mainly based on the specific properties of the signal covariance matrix as well as the decomposition of the observation space into two subspaces, one for the signal and the other for the noise. Here, we are particularly interested in the quality of sources localization considering only the case of uncorrelated radio frequency signals impinging on an antenna array. A measurement system consisting of a linear array antenna and a five-port network applicable to a demodulator such as a receiver is used for the DOA estimation process. Co-simulations performed with the Advanced Device System and Matlab yielded interesting results not only on their performance but also on their limitation.

Introduction L’infliximab (IFX) est un anticorps monoclonal chimerique de la famille des anti-TNFa dont l’efficacite au cours des rhumatismes inflammatoires chroniques, tels que la polyarthrite rhumatoide (PR) et la spondylarthrite ankylosante (SPA), a largement ete demontree au cours des dernieres annees. Si ces nouvelles therapeutiques ont represente une avancee majeure dans la prise en charge de ces maladies, tous les patients ne sont pas repondeurs et, parmi ceux qui le sont, le niveau de reponse est variable d’un individu a l’autre. L’objectif de notre travail est d’etudier la biodisponibilite de l’IFX dans une population de patients suivis pour PR et SPA a la recherche d’une variabilite inter individuelle. Patients et methodes Il s’agit d’une etude descriptive transversale et multicentrique incluant 39 patients suivis pour PR et SPA dans differents services de rhumatologie et de medecine interne qui etaient traites par infliximab (IFX) depuis au moins 14 semaines. Le jour de la perfusion, un prelevement sanguin pour mesure de la concentration plasmatique residuelle d’IFX (C0 IFX) etait pratique et adresse pour dosage par la methode ELISA. Le rapport de C0 IFX par rapport a la dose ponderale prescrite pour chaque patient a ete calcule, refletant ainsi la biodisponibilite du biomedicament. Une remission etait definie pour la PR avec un DAS28 ≤ 2,6 et pour la SPA par un score BASDAI Resultats Trente-neuf patients ont ete inclus : 18 suivis pour PR dont 15 seropositifs, et 21 suivis pour SPA. L’âge moyen etait de 50 ans pour la PR (1H/17F) et 42 ans pour la SPA (14H/7F). La duree moyenne d’evolution de la maladie avant le passage a la biotherapie etait de 8,4 ans pour la PR vs 11 ans pour la SPA et ce pour inefficacite ou intolerance aux traitements conventionnels. La dose ponderale par perfusion d’IFX etait de 3 mg/kg pour 14 PR et de 5 mg/kg pour toutes les SPA ainsi que pour 4 PR. La duree de traitement moyenne par l’IFX etait, au moment de notre etude, de 4 ans, les causes d’arret etant principalement representees par l’echappement therapeutique secondaire. Les dosages ont mis en evidence une variabilite importante de C0 IFX dans les 2 groupes de patients allant de 0 a 6 μg/ml dans le groupe PR et de 0 a 8,32 μg/mL dans le groupe SPA. Quant a la biodisponibilite de l’IFX, pour la PR elle variait entre 0 et 0,64 dans le groupe PR et entre 0 et 1,66 dans le groupe SPA. Ceci confirme l’existence d’une importante variabilite inter individuelle dans les 2 groupes de patients. Conclusion La variabilite de la biodisponibilite de l’IFX d’un patient a l’autre pourrait expliquer en partie les echecs therapeutiques que nous rencontrons chez certains patients. De nombreux facteurs influencent cette biodisponibilite qu’il serait interessant d’etudier dans l’avenir afin d’aller vers une optimisation du traitement.

Background Acute and chronic rejections remain an important cause of graft loss after renal transplantation. It has been suggested that cytokine genotyping may have a predictive role to identify patients at greater risk of rejection regardless of human leukocyte antigen (HLA) compatibility and/or the presence of anti-HLA antibodies before the renal allograft. Objectives We sought to investigate polymorphisms of tumor necrosis factor (TNF)-α, transforming growth factor (TGF)-β1, interleukin (IL)-10, IL-6, and interferon (IFN)-γ as indices of differential cytokine production in kidney transplantation and to examine their predictive roles for acute or chronic rejection. Patients and Methods TNF-α (G/A -308), TGF -β1 (haplotype codon 10/codon 25), IL-10 (haplotype-1082, −819, −592), IL-6 (C/G -174), and IFN-γ (T/A +874) single nucleotide polymorphisms (SNPs) were detected using polymerase chain reaction (PCR)-specific sequence primers (SSP) in 231 kidney transplant recipients (KTR) including 106 treated with mycophenolate mofetil (MMF+). Results We observed no significant associations of any of investigated polymorphism taken alone with acute rejection episodes (ARE) or chronic allograft dysfunction (CAD). Nevertheless, TGF-β1 Low (L) production was correlated with greater graft survival at 20 years (81.8%) compared with intermediate (L) or high (H) levels (56.1%), affect that the difference was not significant (P = .2). Cytokine haplotype analysis in KTR (MMF−) without HLA-mismatches or presynthesized anti-HLA antibodies (n = 32) showed ARE to be significantly more prevalent among the TNF-α*H/TGF- β1*H/IL-10*H production haplotype (75%) compared with the other haplotypes (16%; P = .03). Conclusion The presence of TGF-β1-H secretion profile may protect the kidney graft. TNF-α*H/TGF-β1*H/IL-10*H haplotype was associated with a higher risk of ARE and with poorer graft survival.

The present study describes the strains of hepatitis C virus (HCV) isolated from Tunisian hemodialysis patients. Thirty-three HCV strains isolated from different dialysis centers in Tunis City were amplified by RT-PCR in a region of the NS5b gene, genotyped by sequencing, and compared to international sequences by phylogenetic analysis. The phylogenetic tree showed that 16 HCV isolates have been identified as subtype 4k (48.5%), 7 as unspecified HCV-4 subtype (21.2%), 5 as subtype 4a et 1b (each 15.2%). The analysis of this tree revealed that the HCV-1b strains were closely related to Anglo-Saxon and European isolates, while the HCV-4 isolates are genetically similar to Egyptian and African strains. Phylogenic analysis of 33 Tunisian isolates with international HCV strains on a region of the NS5b gene demonstrated that the subtype 4k submerged the Tunis city and a new subtype of HCV4 seems to be suspect in this area.

The Direction-of-Arrival (DOA) estimation techniques using antenna arrays are applied in large areas of research fields and have received great attention in literature. Mobile communication, Sonar and Radar are just some examples among a large number of possible applications. For example, in military application, it is very important to recognize the direction of any threat. Another example of commercial application is to identify the direction of an emergency cell phone call so that the rescue unit can act in time to the right location. Thereby, DOA estimation using a traditional fixed antenna has many limitations and becomes inappropriate in such applications. In this letter, we describe a DOA estimation system based on an antenna array and five port circuits for detecting arrival angles in azimuth plane of signals pitched by the antenna array. For this, we have based on Multiple Signal Classification (MUSIC) algorithm, which showed a certain limit of its performance in spite of its big reputation by the researchers. In our case, we only consider uncorrelated signals and assume the channel parameters corresponding to a real context. The purpose is to compare the quality of the detected angle in term of precision depending on the number of the samples depicted. ADS software and MATLAB are used to achieve this study. The simulation results on the proposed system designed to operate at 2.4 GHz frequency indicate that MUSIC algorithm is unable to automatically detect and localize the DOA of signals with high accuracy. Other algorithms exist and may provide more precision but require more computation time.