Search

Yousr Gorgi1, Imen Hbibi1, Imen Sfar1, Tahar Gargueh2, Majda Cherif3, Rim Goucha Louzir3, Raoudha Daghbouj 1, Houda Aouadi1, Mouna Makhlouf1, Thouraya Ben Romdhane1, Salwa Jendoubi-Ayed1, Mohamed Amri1, Adel Kheder3, Mohaled R Lakhoua2, Taïeb Ben Abdallah1, Khaled Ayed11Immunology Research Laboratory of Kidney Transplantation and Immunopathology (Laboratoire de recherche LR03SP01), Charles Nicolle Hospital, Tunisia; 2Pediatric department, Charles Nicolle Hospital, Tunisa; 3Nephrology Department, Charles Nicolle Hospital, TunisaAbstract: 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. This study was conducted to determine eventual deficiencies of factor H in the SCR20 gene region and to look for a possible association between the polymorphism (+54) exon 1 of the MBL gene and the predisposition in Tunisian patients with IgAN. We then evaluated the effects of these FH mutations and/or this MBL polymorphism on nephropathy susceptibility and progression. Polymorphism A/B (+54) in the exon1 of the MBL gene and analysis within the C-terminal domain of the protein SCR20 in the exon 22 of the factor H (FH) gene were conducted in 36 sporadic IgAN Tunisian patients and 117 age and gender matched healthy subjects recruited from blood donors, by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing respectively. The analysis of the Gly54Asp (+54) mutation of the MBL gene according to the criteria of gravity of the IgAN reveals that the patients with genotype AB present more frequently with end-stage renal disease (ESRD) compared with those of genotype AA [OR: 8, CI (1.74–54.49), P = 0.019]. Moreover, the variant allele B was stati

Imen Habibi1,Imen Sfar1,Walid Ben Alaya1, Jihen Methlouthi2, Abdelkrim Ayadi2, Mounira Brahim2, Jacques Blouin3, Raoudha Dhagbouj1, Thouraya Ben Rhomdhane1, Mouna Makhlouf1, Houda Aouadi1, Saloua Ayed-Jendoubi1, Véronique Fremeaux-bacchi3, Tahar Sfar2, Taieb Ben Abdallah1, Khaled Ayed1, Yousr Gorgi11Laboratory of Immunology, Charles Nicolle Hospital, Tunis, Tunisia; 2Paediatric Department, Tahar Sfar Hospital, Mahdia, Tunisia; 3Immunology Department, George Pompidou Hospital, Paris, FranceAbstract: 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. This deletion was found as the homozygote form in the proband and as the heterozygote form in the parents. Protein and functional analyses of the complement system were normal in all members of the second family. However, the molecular investigation for the father showed the presence of an amino acid substitution in the FH gene. Unfortunately, his two affected children died without being investigated for mutations. The functional consequences of these abnormal proteins are still to be demonstrated.Keywords: atypical hemolytic uremic syndrome, complement, alternative pathway, factor H, deletion, nucleotide substitution

Imen Habibi1,Imen Sfar1,Walid Ben Alaya1, Jihen Methlouthi2, Abdelkrim Ayadi2, Mounira Brahim2, Jacques Blouin3, Raoudha Dhagbouj1, Thouraya Ben Rhomdhane1, Mouna Makhlouf1, Houda Aouadi1, Saloua Ayed-Jendoubi1, Véronique Fremeaux-bacchi3, Tahar Sfar2, Taieb Ben Abdallah1, Khaled Ayed1, Yousr Gorgi11Laboratory of Immunology, Charles Nicolle Hospital, Tunis, Tunisia; 2Paediatric Department, Tahar Sfar Hospital, Mahdia, Tunisia; 3Immunology Department, George Pompidou Hospital, Paris, FranceAbstract: 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. This deletion was found as the homozygote form in the proband and as the heterozygote form in the parents. Protein and functional analyses of the complement system were normal in all members of the second family. However, the molecular investigation for the father showed the presence of an amino acid substitution in the FH gene. Unfortunately, his two affected children died without being investigated for mutations. The functional consequences of these abnormal proteins are still to be demonstrated.Keywords: atypical hemolytic uremic syndrome, complement, alternative pathway, factor H, deletion, nucleotide substitution

Yousr Gorgi1, Imen Hbibi1, Imen Sfar1, Tahar Gargueh2, Majda Cherif3, Rim Goucha Louzir3, Raoudha Daghbouj 1, Houda Aouadi1, Mouna Makhlouf1, Thouraya Ben Romdhane1, Salwa Jendoubi-Ayed1, Mohamed Amri1, Adel Kheder3, Mohaled R Lakhoua2, Taïeb Ben Abdallah1, Khaled Ayed11Immunology Research Laboratory of Kidney Transplantation and Immunopathology (Laboratoire de recherche LR03SP01), Charles Nicolle Hospital, Tunisia; 2Pediatric department, Charles Nicolle Hospital, Tunisa; 3Nephrology Department, Charles Nicolle Hospital, TunisaAbstract: 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. This study was conducted to determine eventual deficiencies of factor H in the SCR20 gene region and to look for a possible association between the polymorphism (+54) exon 1 of the MBL gene and the predisposition in Tunisian patients with IgAN. We then evaluated the effects of these FH mutations and/or this MBL polymorphism on nephropathy susceptibility and progression. Polymorphism A/B (+54) in the exon1 of the MBL gene and analysis within the C-terminal domain of the protein SCR20 in the exon 22 of the factor H (FH) gene were conducted in 36 sporadic IgAN Tunisian patients and 117 age and gender matched healthy subjects recruited from blood donors, by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) and direct sequencing respectively. The analysis of the Gly54Asp (+54) mutation of the MBL gene according to the criteria of gravity of the IgAN reveals that the patients with genotype AB present more frequently with end-stage renal disease (ESRD) compared with those of genotype AA [OR: 8, CI (1.74–54.49), P = 0.019]. Moreover, the variant allele B was stati