- Email: [email protected]
Complement component 5 deficiency (C5D) in South Africa
Abstracts / Molecular Immunology 48 (2011) 1666–1733
In order to uncover such genetic variability of the disease, we studied whole-genome RNA expression (Agilent) of PBMCs in three non-related HAE type-I families (accounting for 40 individuals), 24 of which carry the same Arg472Stop mutation in the C1-Inhibitor gene. For analytic purposes, those included in this study were clustered according to the presence of mutation and/or clinical symptoms. In all cases, HAE-related treatments were suspended two weeks before biological sampling. Overall, our preliminary results show more than 300 genes differentially expressed in clinically affected and unaffected individuals and suggest the involvement of different pathways in the development of HAE manifestations. In two of the families studied (families AR and Q) transcriptome analysis of the symptoms-developing members reveals significant upregulation (fold change > 2; p < 0.05) of genes involved in RNA translation, endoplasmic reticulum-associated degradation (ERAD), intra-Golgi transport and STAT activation. In the third family (DR), an unexpected highly significant (fold change > 4; p < 0.05) upregulation of the Interferon alpha (IFNalpha)-responsive pathways (including RSADs, OAS, MX, IF transcription factors and ISG pathway members) was observed in the symptomatic individuals. These results, still under study, suggest a mechanistic link between the triggering of edema, protein quality control and the cellular response against viral infections, while standing HAE in the molecular interface between innate and adaptive immunity. doi:10.1016/j.molimm.2011.06.271 P52 The HNA-4a polymorphism, a variant of CD11b subunit of the CR3, in Brazilian systemic lupus erythematosus patients J.E. Toller-Kawahisa a , I.C.C. Vigato b , J.A.T. Pancoto a , J.E.C. Del Lama b , E.A. Donadi a , P. Louzada Júnior a , A.E.C.S. Azzolini b , Y.M. Lucisano-Valim b , C.M. Marzocchi-Machado b,∗ a
Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil b Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
Introduction: The human neutrophil antigen-4a (HNA-4a) (MART) antigen represents a polymorphism of CD11b that has recently been described. Its polymorphism is associated with a single nucleotide substitution (G302A) which causes an Arg61His amino acid substitution on the CD11b of the leucocyte 2 integrin (CD18) family and results in the HNA-4a-negative phenotype. The CD11b is a subunit of the CR3 (CD11b/CD18) and this receptor plays an important synergistic action with FcgR mainly by FcgRIIIb/CR3 cooperation in mediating the immune response to infections and inflammatory processes. Many studies have shown evidence that genetic polymorphism of FcgRIIa (H/R-131) and FcgRIIIb (HNA1a/-1b) is associated with immune abnormalities and risk to the development of systemic lupus erythematosus (SLE).We investigated the HNA-4a polymorphism frequency in SLE associated with FcgR polymorphism. Methods: We determined the HNA-4a genotype frequencies and its association with the FcgRIIa/FcgRIIIb polymorphisms in a group of Brazilian SLE patients (n = 23) and blood donors (n = 64) using a genotyping by PCR with sequence-specific primers. Results: The frequencies of the HNA-4a-negative genotype were 8.69% in SLE and 9.37% in blood donors. The HNA-4a negative genotype was associated with heterozygosis for both FcgRIIa HR-131 and FcgRIIIb HNA-1a,-1b in blood donors. In SLE group the HNA-4a negative genotype was observed in two patients, being one of them
1683
FcgRIIa HR-131 and FcgRIIIb HNA-1a and the other one FcgRIIa R-131 and FcgRIIIb HNA-1a,-1b. Conclusion: These data need to be further investigated regarding the immune effectors’ functions. This study has implications to identify genetic markers that will determine patients who are at high risk of infections. doi:10.1016/j.molimm.2011.06.272 P53 Complement component 5 deficiency (C5D) in South Africa A. Orren a,∗ , T. Owen b , P.C. Potter b , F. Leisegang b , B.P. Morgan a , R. Wurzner c a
Cardiff University, Cardoff, United Kingdom Univ. Cape Town, Cape town, South Africa c Innsbruck Medical Univ., Innsbruck, Austria b
Complement component 6 deficiency (C6Q0) is recognised as a problem in South Africa, but not C5 deficiency (C5D). We diagnosed C5D in a Cape mixed race man (P1) and an African Black woman (P2). Both presented with recurrent meningococcal disease (MD) and the man died from his 5th attack. We identified the known C5 mutation R1476X in P1s mother and investigated his heterozygous sister and his two children. From studies with DNA markers we showed P1 was very probably R1476X homozygous. P2 was heterozygous for the known C5 mutation Q19X and a polymorphism A252T in exon 7; the latter was not believed to be pathological. No other defect could be identified. A252T was present in 5% of 200 Black newborns and 4.8% of 171 adults (Black and Cape mixed race) giving an estimate for homozygotes of 1 in 1600. Adult C5 levels in carriers were significantly lower then in non-carriers. We are now testing all recently diagnosed cases of MD for four C6Q0 defects and the three C5 defects, in order to identify homozygous or compound heterozygous susceptible individuals. Among 95 recent MD individuals we have not identified any with C5 Q19X or R1476X. However, we identified three homozygous A252T individuals. C5 levels have been determined in two, and are less than 1% of those in controls. Thus Q19X and R1476 are rare defects, but A252T is a common cause of C5D and increased MD susceptibility in South Africa. doi:10.1016/j.molimm.2011.06.273 P54 MBL2 genotypes and kidney graft survival Jakob T. Bay a,∗ , Sren S. Srensen b , Jesper Melchior Hansen c , Hans O. Madsen a , Peter Garred a a
Laboratory of Molecular Medicine, Department of Clinical Immunology-7631, Denmark b Department of Nephrology, Rigshospitalet, Denmark c Department of Nephrology, Herlev Hospital, Copenhagen, Denmark Introduction: Conflicting data have been published regarding a possible association between mannose-binding lectin (MBL) levels, MBL genotypes (MBL2) and graft survival in kidney transplantation. Experimental results point towards a role for MBL in ischemia–reperfusion damage in various organs. Thus, we studied the possible association between MBL2 genotypes and graft survival in patients receiving a kidney transplant Patients and methods: DNA was eligible from 669 patients receiving a kidney transplant over a ten years period. MBL2 genotyping was performed using a sequence specific priming technique.
In order to uncover such genetic variability of the disease, we studied whole-genome RNA expression (Agilent) of PBMCs in three non-related HAE type-I families (accounting for 40 individuals), 24 of which carry the same Arg472Stop mutation in the C1-Inhibitor gene. For analytic purposes, those included in this study were clustered according to the presence of mutation and/or clinical symptoms. In all cases, HAE-related treatments were suspended two weeks before biological sampling. Overall, our preliminary results show more than 300 genes differentially expressed in clinically affected and unaffected individuals and suggest the involvement of different pathways in the development of HAE manifestations. In two of the families studied (families AR and Q) transcriptome analysis of the symptoms-developing members reveals significant upregulation (fold change > 2; p < 0.05) of genes involved in RNA translation, endoplasmic reticulum-associated degradation (ERAD), intra-Golgi transport and STAT activation. In the third family (DR), an unexpected highly significant (fold change > 4; p < 0.05) upregulation of the Interferon alpha (IFNalpha)-responsive pathways (including RSADs, OAS, MX, IF transcription factors and ISG pathway members) was observed in the symptomatic individuals. These results, still under study, suggest a mechanistic link between the triggering of edema, protein quality control and the cellular response against viral infections, while standing HAE in the molecular interface between innate and adaptive immunity. doi:10.1016/j.molimm.2011.06.271 P52 The HNA-4a polymorphism, a variant of CD11b subunit of the CR3, in Brazilian systemic lupus erythematosus patients J.E. Toller-Kawahisa a , I.C.C. Vigato b , J.A.T. Pancoto a , J.E.C. Del Lama b , E.A. Donadi a , P. Louzada Júnior a , A.E.C.S. Azzolini b , Y.M. Lucisano-Valim b , C.M. Marzocchi-Machado b,∗ a
Faculdade de Medicina de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil b Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Ribeirão Preto, Brazil
Introduction: The human neutrophil antigen-4a (HNA-4a) (MART) antigen represents a polymorphism of CD11b that has recently been described. Its polymorphism is associated with a single nucleotide substitution (G302A) which causes an Arg61His amino acid substitution on the CD11b of the leucocyte 2 integrin (CD18) family and results in the HNA-4a-negative phenotype. The CD11b is a subunit of the CR3 (CD11b/CD18) and this receptor plays an important synergistic action with FcgR mainly by FcgRIIIb/CR3 cooperation in mediating the immune response to infections and inflammatory processes. Many studies have shown evidence that genetic polymorphism of FcgRIIa (H/R-131) and FcgRIIIb (HNA1a/-1b) is associated with immune abnormalities and risk to the development of systemic lupus erythematosus (SLE).We investigated the HNA-4a polymorphism frequency in SLE associated with FcgR polymorphism. Methods: We determined the HNA-4a genotype frequencies and its association with the FcgRIIa/FcgRIIIb polymorphisms in a group of Brazilian SLE patients (n = 23) and blood donors (n = 64) using a genotyping by PCR with sequence-specific primers. Results: The frequencies of the HNA-4a-negative genotype were 8.69% in SLE and 9.37% in blood donors. The HNA-4a negative genotype was associated with heterozygosis for both FcgRIIa HR-131 and FcgRIIIb HNA-1a,-1b in blood donors. In SLE group the HNA-4a negative genotype was observed in two patients, being one of them
1683
FcgRIIa HR-131 and FcgRIIIb HNA-1a and the other one FcgRIIa R-131 and FcgRIIIb HNA-1a,-1b. Conclusion: These data need to be further investigated regarding the immune effectors’ functions. This study has implications to identify genetic markers that will determine patients who are at high risk of infections. doi:10.1016/j.molimm.2011.06.272 P53 Complement component 5 deficiency (C5D) in South Africa A. Orren a,∗ , T. Owen b , P.C. Potter b , F. Leisegang b , B.P. Morgan a , R. Wurzner c a
Cardiff University, Cardoff, United Kingdom Univ. Cape Town, Cape town, South Africa c Innsbruck Medical Univ., Innsbruck, Austria b
Complement component 6 deficiency (C6Q0) is recognised as a problem in South Africa, but not C5 deficiency (C5D). We diagnosed C5D in a Cape mixed race man (P1) and an African Black woman (P2). Both presented with recurrent meningococcal disease (MD) and the man died from his 5th attack. We identified the known C5 mutation R1476X in P1s mother and investigated his heterozygous sister and his two children. From studies with DNA markers we showed P1 was very probably R1476X homozygous. P2 was heterozygous for the known C5 mutation Q19X and a polymorphism A252T in exon 7; the latter was not believed to be pathological. No other defect could be identified. A252T was present in 5% of 200 Black newborns and 4.8% of 171 adults (Black and Cape mixed race) giving an estimate for homozygotes of 1 in 1600. Adult C5 levels in carriers were significantly lower then in non-carriers. We are now testing all recently diagnosed cases of MD for four C6Q0 defects and the three C5 defects, in order to identify homozygous or compound heterozygous susceptible individuals. Among 95 recent MD individuals we have not identified any with C5 Q19X or R1476X. However, we identified three homozygous A252T individuals. C5 levels have been determined in two, and are less than 1% of those in controls. Thus Q19X and R1476 are rare defects, but A252T is a common cause of C5D and increased MD susceptibility in South Africa. doi:10.1016/j.molimm.2011.06.273 P54 MBL2 genotypes and kidney graft survival Jakob T. Bay a,∗ , Sren S. Srensen b , Jesper Melchior Hansen c , Hans O. Madsen a , Peter Garred a a
Laboratory of Molecular Medicine, Department of Clinical Immunology-7631, Denmark b Department of Nephrology, Rigshospitalet, Denmark c Department of Nephrology, Herlev Hospital, Copenhagen, Denmark Introduction: Conflicting data have been published regarding a possible association between mannose-binding lectin (MBL) levels, MBL genotypes (MBL2) and graft survival in kidney transplantation. Experimental results point towards a role for MBL in ischemia–reperfusion damage in various organs. Thus, we studied the possible association between MBL2 genotypes and graft survival in patients receiving a kidney transplant Patients and methods: DNA was eligible from 669 patients receiving a kidney transplant over a ten years period. MBL2 genotyping was performed using a sequence specific priming technique.