Polimorfismo do gene MASP1, concentrações séricas de MASP-1, MASP-3 e MAp44 e susceptibilidade à hanseníase

Orientadora : Profª. Drª. Iara José de Messias-ReasonCo-orientadora : Profª. Drª. Angelica B. Winter BoldtDissertação (mestrado) - Universidade Federal do Paraná, Setor de Ciências da Saúde, Programa de Pós-Graduação em Ciências Farmacêuticas. Defesa: Curitiba, 23/02/2015Inclui referênciasÁrea de concentração: Análises clínicasResumo: A hanseníase é causada pelo patógeno intracelular obrigatório Mycobacterium leprae, que infecta principalmente macrófagos e células Schwann do hospedeiro. A lectina ligante de manose (MBL) e as ficolinas (FCNs) reconhecem padrões de açúcares e resíduos acetilados (PAMP), respectivamente, em uma ampla variedade de patógenos, incluindo o M. leprae. Este reconhecimento desencadeia a transativação das serina-proteases 1 e 2, associadas a MBL (MASP-1 e MASP-2), e em seguida, a ativação da via das lectinas do sistema complemento. O gene MASP1 apresenta diversos polimorfismos que estão associados à modulação das concentrações de MASP-1 e de mais duas outras proteínas, resultantes de processamento alternativo do pré-mRNA: MASP-3 e a forma não-enzimática MAp44, ambas envolvidas na regulação negativa do sistema complemento, através da competição pelos sítios de ligação aos PAMP nas moléculas de reconhecimento. Neste estudo, avaliamos possível associação entre polimorfismos do gene MASP1 e concentrações séricas de MASP-1, MASP-3 e MAp44 em 389 indivíduos da população brasileira e 210 da dinamarqueses (segundo grupo controle), assim como com a susceptibilidade à hanseníase em 196 pacientes e 193 controles do Sul do Brasil. As amostras foram genotipadas por PCR sequência-específica multiplex para g.8113G>A (rs7609662) e g.8795C>T (rs13064994), localizados no intron 01, e g.61897C>G (rs72549262), g.62223C>T (rs1109452) e g.62224G>A (rs850314), localizados no exon 12 do gene MASP1. Os níveis séricos das proteínas foram quantificados com ensaio imunofluorimétrico cronometrado (TRIFMA). Pacientes com hanseníase apresentaram concentrações séricas de MASP-3 e MAp44 menores do que controles (medianas: 4603 ng/ml vs. 5606 ng/ml para MASP-3, pA (rs7609662) and g.8795C>T (rs13064994) located in intron 01 and g.61897C>G (rs72549262), g.62223C>T (rs1109452) and g.62224G>A (rs850314) located in exon 12 of MASP1 gene. Protein serum levels were quantified by time-resolved immunofluorometric assays (TRIFMA). Leprosy patients presented lower MASP-3 and MAp44 serum levels (median: 4603 ng/ml vs. 5606 ng/ml for MASP-3, p<0.005; 1732 vs. 2350 ng/ml for MAp44, p<0.0001). Patients presenting the lepromatous clinical form of Leprosy also showed lower MASP-3 and MAp44 serum levels when compared to non-lepromatous patients (P=0.0016 and P<0.0001). There was an association between the T allele of rs1109452 with higher MASP-1 and lower MASP-3 serum levels in all three groups. The GC CCG haplotype was related to susceptibility to Leprosy (P=0.028, OR=1.43 [CI95%=1.04-1.94]). The exon 12 haplotype distribution is associated to MASP-3 levels in controls (P=0.012) and Danish (P=0.0006), and the genotypes of this variants, also revealed an association with MAp44 levels in patients (P=0.023), with MASP-3 levels in controls (P=0.024) and MASP-3 levels in the Danish cohort group (P<0,0001). Low MASP-3 and MAp44 serum levels in leprosy may be conferred by haplotypes/genotypes of MASP1 gene in addition to possible protein consumption and/or low production in leprosy patients. Key-words: MASP1, MASP-3, MAp44, MBL-associated serine-protease, complement, lectin pathway, leprosy

MASP-1 and MASP-2 Serum Levels Are Associated With Worse Prognostic in Cervical Cancer Progression

Background: MBL-associated serine proteases (MASP-1, MASP-2, MASP-3, MAp-44, and MAp-19) are key factors in the activation of the lectin pathway of complement. Serum levels of these components have been associated with recurrence and poor survival of some types of cancer, such as colorectal and ovarian cancer. In this investigation, we determined the serum levels of MASP-1, MASP-2, MASP-3, MAp-44, and MAp-19 in patients with cervical cancer and cervical intraepithelial neoplasia (CIN).Methods:A total of 351 women who underwent screening for cervical cancer or treatment at the Erasto Gaertner Cancer Hospital in Curitiba-Brazil, were enrolled in the study. Based on their latest cervical colposcopy-guided biopsy results, they were divided into four groups: CIN-I: n = 52; CIN-II: n = 73; CIN-III: n = 141; and invasive cancer: n = 78. All the serum protein levels were determined by time-resolved immunofluorometric assay (TRIFMA).Results:Patients with invasive cancer presented significantly higher MASP-2, MASP-1, and MAp-19 serum levels than other groups (p &lt; 0.0001; p = 0.012; p = 0.025 respectively). No statistically significant differences in MASP-3 and MAp-44 serum levels were found between the four studied groups. In addition, high MASP-2, MASP-1, and MAp-19 serum levels were significantly associated with poor survival in patients with invasive cancer and relapse (p = 0.002, p = 0.0035 and p = 0.025, respectively).Conclusion:High MASP-2, MASP-1, and MAp-19 serum levels were associated with cervical cancer progression and worse disease prognosis. These novel findings demonstrate the involvement of the serine proteases of the lectin pathway in the pathogenesis of cervical cancer and future investigations should clarify their role in the disease process

Ficolin-1 and Ficolin-3 Plasma Levels Are Altered in HIV and HIV/HCV Coinfected Patients From Southern Brazil

The complement system is a key component of the innate immune system, participating in the surveillance against infectious agents. Once activated by one of the three different pathways, complement mediates cell lysis, opsonization, signalizes pathogens for phagocytosis and induces the adaptive immune response. The lectin pathway is constituted by several soluble and membrane bound proteins, called pattern recognition molecules (PRM), including mannose binding lectin (MBL), Ficolins-1, -2, and -3, and Collectin 11. These PRMs act on complement activation as recognition molecules of pathogen-associated molecular patterns (PAMPs) such as N-acetylated, found in glycoproteins of viral envelopes. In this study, Ficolin-1 and Ficolin-3 plasma levels were evaluated in 178 HIV patients (93 HIV; 85 HIV/HCV) and 85 controls from southern Brazil. Demographic and clinical-laboratory findings were obtained during medical interview and from medical records. All parameters were assessed by logistic regression, adjusted for age, ancestry, and sex. Significantly lower levels of Ficolin-1 were observed in HIV/HCV coinfected when compared to HIV patients (p = 0.005, median = 516 vs. 667 ng/ul, respectively) and to controls (p &lt; 0.0001, 1186 ng/ul). Ficolin-1 levels were lower in males than in females among HIV patients (p = 0.03) and controls (p = 0.0003), but no association of Ficolin-1 levels with AIDS was observed. On the other hand, Ficolin-3 levels were significantly lower in controls when compared to HIV (p &lt; 0.0001, medians 18,240 vs. 44,030 ng/ml, respectively) and HIV/HCV coinfected (p &lt; 0.0001, 40,351 ng/ml) patients. There was no correlation between Ficolin-1 and Ficolin-3 levels and age, HIV viral load or opportunistic infections. However, Ficolin-3 showed a positive correlation with T CD4 cell counts in HIV monoinfected patients (p = 0.007). We provide here the first assessment of Ficolin-1 and−3 levels in HIV and HIV/HCV coinfected patients, which indicates a distinct role for these pattern recognition molecules in both viral infections

High-throughput functional analysis of autism genes in zebrafish identifies convergence in dopaminergic and neuroimmune pathways

Advancing from gene discovery in autism spectrum disorders (ASDs) to the identification of biologically relevant mechanisms remains a central challenge. Here, we perform parallel in vivo functional analysis of 10 ASD genes at the behavioral, structural, and circuit levels in zebrafish mutants, revealing both unique and overlapping effects of gene loss of function. Whole-brain mapping identifies the forebrain and cerebellum as the most significant contributors to brain size differences, while regions involved in sensory-motor control, particularly dopaminergic regions, are associated with altered baseline brain activity. Finally, we show a global increase in microglia resulting from ASD gene loss of function in select mutants, implicating neuroimmune dysfunction as a key pathway relevant to ASD biology

Expression of dlx genes in the normal and regenerating brain of adult zebrafish.

Dysfunctions in the GABAergic system lead to various pathological conditions and impaired inhibitory function is one of the causes behind neuropathies characterized by neuronal hyper excitability. The Dlx homeobox genes are involved in the development of nervous system, neural crest, branchial arches and developing appendages. Dlx genes also take part in neuronal migration and differentiation during development, more precisely, in the migration and differentiation of GABAergic neurons. Functional analysis of dlx genes has mainly been carried out in developing zebrafish embryos and larvae, however information regarding the expression and roles of these genes in the adult zebrafish brain is still lacking. The extensive neurogenesis that takes place in the adult zebrafish brain, makes them a good model for the visualization of mechanisms involving dlx genes during adulthood in physiological conditions and during regeneration of the nervous system. We have identified the adult brain regions where transcripts of dlx1a, dlx2a, dlx5a and dlx6a genes are normally found and have confirmed that within telencephalic domains, there is high overlapping expression of the four dlx paralogs with a marker for GABAergic neurons. Co-localization analyses carried with the Tg(dlx6a-1.4kbdlx5a/dlx6a:GFP) reporter line have also shown that in some areas of the diencephalon, cells expressing the dlx5a/6a bigene may have a neural stem cell identity. Furthermore, investigations in a response to stab wound lesions, have demonstrated a possible participation of the dlx5a/6a bigene, most likely of dlx5a, during regeneration of the adult zebrafish brain. These observations suggest a possible participation of dlx-expressing cells during brain regeneration in adult zebrafish and also provide information on the role of dlx genes under normal physiological conditions in adults

Adding MASP1 to the lectin pathway-Leprosy association puzzle: Hints from gene polymorphisms and protein levels.

BackgroundDeposition of complement factors on Mycobacterium leprae may enhance phagocytosis. Such deposition may occur through the lectin pathway of complement. Three proteins of the lectin pathway are produced from the gene MASP1: Mannan-binding lectin-associated serine protease 1 (MASP-1) and MASP-3 and mannan-binding lectin-associated protein of 44 kDa (MAp44). Despite their obvious importance, the roles played by these proteins have never been investigated in leprosy disease.MethodologyWe haplotyped five MASP1 polymorphisms by multiplex sequence-specific PCR (intronic rs7609662*G>A and rs13064994*C>T, exon 12 3'-untranslated rs72549262*C>G, rs1109452*C>T and rs850314*G>A) and measured MASP-1, MASP-3 and MAp44 serum levels in 196 leprosy patients (60%, lepromatous) and 193 controls.Principal findingsLower MASP-3 and MAp44 levels were observed in patients, compared with controls (P = 0.0002 and PConclusionPolymorphisms regulating MASP-3/MAp44 availability in serum modulate leprosy susceptibility, underlining the importance of lectin pathway regulation against pathogens that exploit phagocytosis to parasitize host macrophages

Pyridoxine-Dependent Epilepsy in Zebrafish Caused by Aldh7a1 Deficiency

Pyridoxine-dependent epilepsy (PDE) is a rare disease characterized by mutations in the lysine degradation gene ALDH7A1 leading to recurrent neonatal seizures, which are uniquely alleviated by high doses of pyridoxine or pyridoxal 5'-phosphate (vitamin B6 vitamers). Despite treatment, neurodevelopmental disabilities are still observed in most PDE patients underlining the need for adjunct therapies. Over 60 years after the initial description of PDE, we report the first animal model for this disease: an aldh7a1-null zebrafish (Danio rerio) displaying deficient lysine metabolism and spontaneous and recurrent seizures in the larval stage (10 days postfertilization). Epileptiform electrographic activity was observed uniquely in mutants as a series of population bursts in tectal recordings. Remarkably, as is the case in human PDE, the seizures show an almost immediate sensitivity to pyridoxine and pyridoxal 5'-phosphate, with a resulting extension of the life span. Lysine supplementation aggravates the phenotype, inducing earlier seizure onset and death. By using mass spectrometry techniques, we further explored the metabolic effect of aldh7a1 knockout. Impaired lysine degradation with accumulation of PDE biomarkers, B6 deficiency, and low γ-aminobutyric acid levels were observed in the aldh7a1-/- larvae, which may play a significant role in the seizure phenotype and PDE pathogenesis. This novel model provides valuable insights into PDE pathophysiology; further research may offer new opportunities for drug discovery to control seizure activity and improve neurodevelopmental outcomes for PDE

Pyridoxine-Dependent Epilepsy in Zebrafish Caused by Aldh7a1 Deficiency

Pyridoxine-dependent epilepsy (PDE) is a rare disease characterized by mutations in the lysine degradation gene ALDH7A1 leading to recurrent neonatal seizures, which are uniquely alleviated by high doses of pyridoxine or pyridoxal 5'-phosphate (vitamin B6 vitamers). Despite treatment, neurodevelopmental disabilities are still observed in most PDE patients underlining the need for adjunct therapies. Over 60 years after the initial description of PDE, we report the first animal model for this disease: an aldh7a1-null zebrafish (Danio rerio) displaying deficient lysine metabolism and spontaneous and recurrent seizures in the larval stage (10 days postfertilization). Epileptiform electrographic activity was observed uniquely in mutants as a series of population bursts in tectal recordings. Remarkably, as is the case in human PDE, the seizures show an almost immediate sensitivity to pyridoxine and pyridoxal 5'-phosphate, with a resulting extension of the life span. Lysine supplementation aggravates the phenotype, inducing earlier seizure onset and death. By using mass spectrometry techniques, we further explored the metabolic effect of aldh7a1 knockout. Impaired lysine degradation with accumulation of PDE biomarkers, B6 deficiency, and low g-aminobutyric acid levels were observed in the aldh7a1(-/-) larvae, which may play a significant role in the seizure phenotype and PDE pathogenesis. This novel model provides valuable insights into PDE pathophysiology; further research may offer new opportunities for drug discovery to control seizure activity and improve neurodevelopmental outcomes for PD