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.

Phylogenetic analysis of isolated HCV strains from tunisian hemodialysis patients.

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.

Chemokine and chemokine receptor gene polymorphism in Tunisian hemodialysis patients with HCV infection.

Introduction: Our aim was to investigate the possibility of a significant relationship between chemokines and chemokine receptor genes polymorphisms and the spontaneous clearance or the persistence of HCV infection.

Methods: A total of 96 hemodialysis (HD) patients infected with HCV were classified into two groups: G1 included 73 patients with persistently positive HCV-RNA and G2 included 23 HD patients who have spontaneously eliminated the virus. The control group consisted of 170 healthy blood donors.

Cytokine and apoptosis gene polymorphisms influence the outcome of hepatitis C virus infection.

Background: Hepatitis C virus (HCV) infection is thought to be chronic and the factors leading to viral clearance or persistence are poorly understood. This study was undertaken to investigate the possibility of a significant relationship between the spontaneous clearance or the persistence of hepatitis C virus (HCV) infection and cytokine and apoptosis gene polymorphisms in Tunisian patients on hemodialysis.

Methods: Polymorphisms of the genes IL-1 (-889 IL-1alpha, -511 and +3954 IL-1beta, IL-1Ra), IL-18 (-137 and -607), IL-12 (-1188) and Apo1/Fas (-670) were determined by PCR-RFLP, PCR-SSP and PCR-VNTR in 100 healthy blood donors and 100 patients infected with HCV and undergoing hemodialysis.

CD86 +1057G>A polymorphism and susceptibility to acute kidney allograft rejection.

Introduction: CD86 is a costimulatory molecule that participates in the regulation of T-cell lymphocytes activation. Thus, we examined a genetic marker on the CD86 gene in kidney transplant outcome.

Materials And Methods: In our retrospective study, 168 kidney allograft recipients were genotyped by direct sequencing.

Anti-CCP antibodies, rheumatoid factors and anti-keratin antibodies: clinical value in established rheumatoid arthritis.

Background: It is well documented that in early rheumatoid arthritis, anti-CCP antibodies have better diagnostic value than rheumatoid factors and anti-keratin antibodies. However, their role is less well defined in patients with established or long duration disease.

Aim: To evaluate and to compare diagnostic performances of anti- CCP, anti-keratin, IgM and IgA rheumatoid factors in established rheumatoid arthritis.

Interleukin-18 gene polymorphisms in tunisian patients with inflammatory bowel disease.

Aim: Interleukin (IL)-18 can regulate the Th2-mediated immune response and it may be involved in the pathogenesis of Th1 and Th2 chronic inflammatory diseases. This study sought to detect a possible association between two single nucleotide polymorphisms (SNPs) (-137G/C and -607C/A) in the IL-18 gene promoter region and susceptibility to inflammatory bowel disease (IBD) including Crohn's disease (CD) and ulcerative colitis (UC) in the Tunisian population.

Methods: The (-137G/C and -607C/A) IL-18 polymorphism was analyzed in 105 patients with CD, 59 patients with UC, and 100 controls using the sequence-specific polymerase chain reaction method.

[Hepatitis C in kidney transplantation: comparative study between two Maghrebin centers: Casablanca and Tunis].

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):.

[IL1/IL1 Ra, CTLA-4 and Apo1/Fas genes polymorphisms and susceptibility to IgA nephropathy in Tunisian patients].

Background: The IgA nephropathy (IgA-N) is considered the most common form of primary glomerulonephritis and its pathogenic mechanisms are very complex. The study of several genes which encode for immunoregulator molecules in inflammatory and immunological responses during the disease, allowed to describe some number of polymorphisms would be involved in the molecular expression, the road marking, the synthesis and\or the binding to the receptors. So an abnormality of the molecular function associated with its polymorphism would be suggested in the genetic predisposition to the disease.

Lymphoid tyrosine phosphatase R620W variant and inflammatory bowel disease in Tunisia.

Aim: To assess the possible association between PTPN22 (R620W) gene polymorphism and inflammatory bowel disease (IBD).

Methods: One hundred and sixty-four patients with IBD [105 Crohn's disease (CD) and 59 ulcerative colitis (UC)] and 100 healthy controls were recruited. Genotyping of the PTPN22 gene 1858C-->T polymorphism was performed by restriction fragment length polymorphism-polymerase chain reaction with RsaI digestion.

Atypical hemolytic uremic syndrome and mutation analysis of factor H gene in two Tunisian families.

We carried out a protein and genetic investigation of the factor H gene mutations within two families presenting with a diagnostic suspicion of atypical hemolytic uremic syndrome (aHUS). The results within the patients of the first family revealed a factor H-deficiency. Direct sequencing allowed the detection of a 4-nucleotide deletion in the factor H gene.

Role of genetic polymorphisms in factor H and MBL genes in Tunisian patients with immunoglobulin A nephropathy.

The molecular mechanisms of IgA nephropathy (IgAN) remain poorly understood. Several different polymorphic genes have been investigated in order to demonstrate their possible association with this disease. It is evident that mainly alternative and lectin pathways complement activation and play an important role in renal injury of IgAN.

Association of Fas/Apo1 gene promoter (-670 A/G) polymorphism in Tunisian patients with IBD.

Aim: To detect a possible association between the polymorphism of the (-670 A/G) Fas/Apo1 gene promoter and susceptibility to Crohn's disease (CD) and ulcerative colitis (UC) in the Tunisian population.

Methods: The (-670 A/G) Fas polymorphism was analyzed in 105 patients with CD, 59 patients with UC, and 100 controls using the polymerase chain reaction restriction fragment length polymorphism method.

Results: Significantly lower frequencies of the Fas -670 A allele and A/A homozygous individuals were observed in CD and UC patients when compared with controls.

Association between CTLA-4 gene promoter (49 A/G) in exon 1 polymorphisms and inflammatory bowel disease in the Tunisian population.

Background/aim: To investigate the possible association between the polymorphism of the CTLA-4 exon 1 +49 A/G and susceptibility to Crohn's disease (CD) and ulcerative colitis (UC) in the Tunisian population.

Methods: The +49 A/G dimorphism was analyzed in 119 patients with CD, 65 patients with UC, and 100 controls by the polymerase chain reaction-restriction fragment length polymorphism method.

Results: Significantly higher frequencies of the CTLA-4 +49A allele and A/A homozygous individuals were observed in patients with CD when compared with controls (pc = 0.

VEGF and mRNA VEGF expression in CSF from Behçet's disease with neurological involvement.

Vascular endothelial growth factor (VEGF) stimulates angiogenesis, but is also pro-inflammatory and plays an important role in the development of neurological disease, where it can have both attenuating and exacerbating effects. Several studies have indicated that VEGF-A (VEGF) may play a role in the pathogenesis of neurological inflammatory diseases. To assess the role of VEGF in patients with Behçet's disease with neurological involvement, VEGF was measured in the cerebrospinal fluid (CSF) of 32 patients compared to a group of 12 patients with noninflammatory neurological diseases (NIND) and 14 patients with multiple sclerosis (MS).

[Vascular trombosis of renal graft: 9 cases].

Background: Allograft renal thrombosis can occur in 1 to 6% of cases. Many predisposing factors has been identified especially alteration of coagulation.

Aim: We analyzed in this study frequency and predisposing factors of renal graft thrombosis.

Acute rejection episodes after kidney transplantation.

Acute rejection episodes (AREs) are a major determinant of renal allograft survival. The incorporation of new immunosuppressive agents explains, at least partially, the improvement seen in the results of transplantation in recent years. The objectives of this study are to analyze the incidence and severity of AREs, their risk factors and their influence on graft and patient survival.

Polymorphism in ICAM-1, PECAM-1, E-selectin, and L-selectin genes in Tunisian patients with inflammatory bowel disease.

Background: Ulcerative colitis (UC) and Crohn's disease (CD) are chronic intestinal disorders characterized by immune dysregulation and leukocytes recruitment into gastrointestinal tract. Cell adhesion molecules (CAM) mediate the extravasation of leukocytes and their accumulation in inflamed intestinal mucosa. Recently, CAM genes have been implicated in determining susceptibility to UC and CD.

Role of immune system, apoptosis and angiogenesis in pathogenesis of rheumatoid arthritis and joint destruction, a systematic review.

Background: Rheumatoid arthritis (RA) is a chronic inflammatory disorder of unknown cause that is notorious for the chronic polyarticular synovial inflammation and progressive destruction of affected joints. Understanding the pathogenesis of RA provides the basis for optimal management of that disease in patients. The pathogenesis of RA was largely explored in many studies in human as much as in mice models with collagen II induced arthritis, nevertheless the pathogenesis puzzle is still incomplete.

Human platelet antigens polymorphisms and susceptibility of thrombosis in hemodialysis patients.

To investigate the association between the polymorphisms of human platelet antigen (HPA)-1,2,3,4,5 and susceptibility to develop thrombosis accident in arteriovenous fistula (AVF), genomic DNA of 112 hemodialysis (HD) patients and 100 healthy blood donors were genotyped by PCR-SSP. The patients were classified into 2 groups: G1 included 54 HD patients presented at least one thrombotic episode on the level of the AVF, and G2 included 58 HD patients without any episode of thrombosis. The allelic frequencies of HPA-1, 2, 3, and 5 among patients and controls did not reveal significant differences.

Distribution of HLA-B*27 subtypes in Tunisians and their association with ankylosing spondylitis.

Objective: The human leukocyte antigen HLA-B27 is a class I antigen of the major histocompatibility complex strongly associated with ankylosing spondylitis (AS) and other related spondyloarthropathies (SpAs). The mechanism of this association remains unknown. HLA-B27 is a serologic specificity that represents a family of at least 25 different HLA-B27 alleles (2701-2725).

Comparison of HLA Class I and II Molecular and Serological Typing within Clinical Laboratory.

In order to develop an adequate tissue typing strategy, we performed human leukocyte antigen (HLA)-A, B and DR generic typing on 235 (120 HLA-A, B and 115 HLA-DR) routine clinical samples by polymerase -chain reaction (PCR)-SSP in parallel with conventional serological typing. At the A locus, there were two (1.7%) discrepancies between molecular and serological typing besides 25 (20.

Clearance and persistence of hepatitis C virus in a Tunisian population: association with HLA class I and class II.

Human leukocyte antigens (HLAs) of class I and class II are reported to influence the outcome of hepatitis C virus (HCV) infection. The aim of this study was to assess the role of HLA class I and class II in influencing spontaneous viral clearance or persistence in HCV-infected patients. HLA class I (A and B) typing was performed by lymphocytotoxicity test and HLA class II (DRB1) was determined by low-resolution PCR-SSP (polymerase chain reaction amplification with sequence-specific primers) for 99 subjects (48 men and 51 women).

Hepatitis B virus genotypes and precore/core-promoter mutations in Tunisian patients with chronic hepatitis B virus infection.

Objective: The aim of this study was to determine the frequency of genotype and precore/core-promoter mutations in chronic hepatitis B virus (HBV) infected individuals in Tunisia.

Methods: We studied 164 Tunisian patients (38 HBeAg-positive and 126 HBeAg-negative) with chronic HBV infection. Genotypes and precore/core-promoter mutations were studied using Inno-LiPA and Multiplex-PCR and PCR-RFLP methodology.

Discrepancies of NKT cells expression in peripheral blood and in cerebrospinal fluid from Behçet's disease.

The precise role of natural killer T (NKT) cells in the pathogenesis of Behçet's disease (BD) remains unknown. The frequency, cytokine profile and heterogeneity of NKT cells were studied in peripheral blood mononuclear cells (PBMC) from 42BD patients and in cerebrospinal fluid (CSF) samples from 9 neuro-BD patients. Flow cytometry revealed a decreased frequency of NKT cells in PBMC from BD patients (median: 0.