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Chronic Hepatitis C is one of the most important risk factors of liver cirrhosis and hepatocellular carcinoma. Before reaching these ultimate steps, insulin resistance triggered by hepatitis C virus infection is known to participate in the progression of liver disease. The present study aims to investigate the influence of two functional polymorphisms on SOCS3 mRNA expression and on the outcomes of CHC progression in a North African context.In this case-control study, 601 Moroccan subjects composed of 200 healthy controls, 101 resolvers and 300 patients with persistent HCV infection including 95 mild chronic hepatitis, 131 Advanced Liver Diseases and 74 HCC were enrolled. They were genotyped for the 4874 A/G (rs4969170) and A + 930- G (rs4969168) SOCS3 variants using TaqMan SNPs assays. SOCS3 mRNA expression was assessed using Real Time PCR technique.Logistic regression analysis showed that variation at rs4969168 was associated with spontaneous clearance of HCV (P 0.05). In addition, minor allele frequencies were significantly higher in AdLD patients when compared to the mCHC group both for rs4969168 (P = 7.0 E-04) and rs4969170 (P = 4.0 E-05). A significant association between haplotype and liver disease progression was also found. Moreover, SOCS3 mRNA was significantly more expressed in peripheral leukocytes from patients with HCC than in those from mCHC. Finally, rs4969170 was significantly associated with LDL-lipoprotein (P = 0.04), total cholesterol (P = 5.0 E-04), and higher fasting glucose levels (P = 0.005) in patients with persistent HCV infection.Our results underline the importance of the functional SOCS3 polymorphisms in the modulation of CHC progression and suggest their contribution to HCC development by affecting its mRNA expression and perturbing key metabolic parameters.

International audience; X-linked agammagobulinemia (XLA) is a primary immunodeficiency caused by Bruton's tyrosine kinase (BTK) gene defect. XLA patients have absent or reduced number of peripheral B cells and a profound deficiency in all immunoglobulin isotypes. This multicenter study reports the clinical, immunological and molecular features of Bruton's disease in 40 North African male patients. Fifty male out of 63 (male and female) patients diagnosed with serum agammaglobulinemia and non detectable to less than 2 % peripheral B cells were enrolled. The search for BTK gene mutations was performed for all of them by genomic DNA amplification and Sanger sequencing. We identified 33 different mutations in the BTK gene in 40 patients including 12 missense mutations, 6 nonsense mutations, 6 splice-site mutations, 5 frameshift, 2 large deletions, one complex mutation and one in-frame deletion. Seventeen of these mutations are novel. This large series shows a lower frequency of XLA among male patients from North Africa with agammaglobulinemia and absent to low B cells compared with other international studies (63.5 % vs 85 %). No strong evidence for genotype-phenotype correlation was observed. This study adds to other reports from highly consanguineous North African populations, showing lower frequency of X-linked forms as compared to AR forms of the same primary immunodeficiency. Furthermore, a large number of novel BTK mutations were identified and could further help identify carriers for genetic counseling.

Distinction between Brucella melitensis infected and vaccinated sheep is needed to fully achieve ovine brucellosis eradication in several countries. For this purpose, we probed immunoblots of cytosoluble protein extract (CPE) of the rough (R) B. melitensis strain B115 with sera of Brucella-free, naturally infected, B. melitensis H38 experimentally infected and B. melitensis Rev.1 vaccinated sheep to identify immunogenic Brucella cytosoluble proteins which may lead to the development of more useful diagnostic tests and which may eventually differentiate vaccinated sheep from infected sheep. Brucella-free sheep sera showed IgM antibody reactivity to protein bands between 19 and 92 kDa. The use of conjugate specific for sheep IgG avoided non specific reactivity to all these bands except to the 39 and 50 kDa bands which were still detected in some Brucella-free sheep sera. In sera of B. melitensis H38 experimentally infected sheep, a specific IgG antibody response was observed against proteins of molecular masses of 19, 24, 28, 32, 39, 50 and 54 kDa. These proteins were also variably detected by IgG of sera from naturally infected sheep. Other proteins of 10, 12, 23, 36, 38, 42, 46, 68, 80 and 92 kDa were also detected by the latter sera. In sera from B. melitensis Rev.1 vaccinated sheep, an IgG antibody response was only observed against proteins with molecular masses of 39 and 50 kDa. These results suggest that the 19, 24, 28, 32 and 54 kDa proteins (the first recognized after experimental infection and that provoked a consistent humoral response during natural infection) could be interesting to develop serological tests for differentiating B. melitensis infection from B. melitensis Rev.1 vaccination.

Sera from Brucella infected and B. melitensis Rev1 vaccinated sheep were analysed by immunoblotting using the cell envelope fraction (CEF) of B. melitensis B115. The CEF of B. melitensis B115 was analysed using a bank of monoclonal antibodies. The fraction consisted mainly of S-LPS like molecules, R-LPS and outer membrane proteins (OMPs) of molecular masses of 10, 16.5, 19, 25–27, 31–34, 36–38, 73 and 89 kDa. Immunoblot analysis indicates that the antibody response in infected sheep was mainly directed against the major OMPs of 25–27, 31–34, 36–38 kDa, against 55 to 62, 70–73 and 89 to 94 kDa proteins associated with the CEF and, against S-LPS like molecules. Some infected sheep reacted with antigens of molecular mass lower than 20 kDa. Sera from vaccinated sheep reacted only with OMPs of 36–38, 60, 70–73 and 89 kDa. The major 25–27 and 31–34 kDa OMPs and proteins below 20 kDa were only detected by the sera of infected sheep. These differences may be due to the persistence of the field infection also reflected by the fact that antibody response against O-polysaccharide (O-PS), as measured by enzyme-linked immunosorbent assay (ELISA), was more intense in infected sheep than in vaccinated ones. These results also indicate that these OMPs could be useful to differentiate B. melitensis infection from B. melitensis Rev.1 vaccination in sheep.

International audience; OBJECTIVES: The aim of this study was to determine the prevalence of Hepatitis B Virus (HBV) genotypes, subgenotypes, HBV surface antigen (HBsAg) subtypes and naturally occurring mutations in Major Hydrophilic region (MHR) of HBsAg among Moroccan patients with chronic HBV infection. METHODS: The study included 200 patients chronically infected with HBV. The HBV genotypes, subgenotypes, HBsAg subtypes and MHR variants were determined by direct sequencing of the HBV surface (S) gene and phylogenetic analysis. RESULTS: The S gene was successfully amplified in 134 patients. The mean age was 40.6 ± 12.2 years. Genotype D was predominant (90%, 120/134) and genotype A was less frequent (10%, 14/134). Genotype D strains belonged to subgenotypes D7 (70.8%, 85/120), D1 (25.8%, 31/120) and D2 (0.9%, 1/120). Three strains (2.5%) could not be classified in any subgenotype of genotype D. All genotype A strains belonged to subgenotype A2. HBsAg subtypes found were ayw2 (82.1%, 110/134), adw2 (10.4%, 14/134), ayw3 (3%, 4/134) and ayw4 (3%, 4/134). The global prevalence of MHR variants was 15% (20/134) with substitution P120T/S the most frequent (3.7%, 5/134). The occurrence of MHR variants was significantly associated with advancing age (>40 years) (p = 0.003) and independent of sex, HBeAg status, viral load, genotype, subgenotype and HBsAg subtype. CONCLUSIONS: This study provides the first description of predominance of HBV subgenotype D7/subtype ayw2 among Moroccan HBV chronic carriers. It also showed a significant prevalence of naturally occurring MHR variants in Morocco.

Competitive enzyme-linked immunosorbent assay (C-ELISA) was performed using 15 monoclonal antibodies (MAbs), specific for Brucella BP26 (previously also called CP28), a periplasmic protein antigen, to investigate antibody responses in naturally and B. melitensis H38 experimentally infected and B. melitensis Rev.1 vaccinated sheep. The antigen preparation consisted of cytosoluble protein extract (CPE) of B. melitensis B115. By combining the C-ELISA results of several MAbs, a high percentage of naturally infected animals were detected which showed different status in the current conventional diagnostic tests. Indeed, 90% of sheep which were positive in the conventional bacteriological and serological tests were positive in C-ELISA. 72% of the bacteriologically negative but serologically and delayed type hypersensitivity positive sheep were also positive in the C-ELISA. Moreover, 79% of the bacteriologically and serologically negative sheep but delayed type hypersensitivity positive were also detected by C-ELISA. Thus, these results confirmed the importance of BP26 as a frequently recognized target of the humoral immune response of infected sheep. The 8 B. melitensis H38 experimentally infected sheep showed various degrees of antibody responses at the 90th day after infection, which was delayed in comparison to that against O-polysaccharide (O-PS). Of the 15 MAbs tested, only one MAb was weakly inhibited (20 to 35% inhibition) by 56% of negative control sera. Furthermore, no antibody response against BP26 was detected in B. melitensis Rev.1 vaccinated sheep. Results of the C-ELISA with the 15 MAbs showed individual variability of the antibody responses against BP26. Thus, it is suggested that several epitopes of BP26 are of interest for diagnosis of B. melitensis infection in sheep.