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Background Deposition 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. Methodology We 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 findings Lower MASP-3 and MAp44 levels were observed in patients, compared with controls (P = 0.0002 and P, Author summary Since immemorial times, Mycobacterium leprae inflicts permanent injuries in human kind, within a wide symptomatic spectrum ranging from insensitive skin patches to disabling physical lesions. Innate resistance to this parasite is well recognized, but poorly understood. The complement system is one of the most important arms of the innate response, and several lines of evidence indicate that it may be usurped by the parasite to enhance its entrance into host cells. These include our recent work on genetic association of the disease with lectin pathway components and the complement receptor CR1, whose polymorphisms modulate susceptibility to infection and clinical presentation. Here, we add another pivotal piece in the leprosy parasite-host interaction puzzle: polymorphisms and serum levels of three different lectin pathway proteins, all encoded by the same gene, namely mannan-binding lectin-associated serine protease 1 (MASP1). We found lower levels of two of these proteins, MASP-3 and MAp44, in leprosy patients. Higher MASP-3/lower MASP-1 levels were associated with protective haplotypes, containing two side-by-side polymorphisms located in the exclusive untranslated region of MASP-3 exon 12, which may regulate exon splicing and/or translation efficiency. The associations revealed in this study reflect the pleiotropic nature of this gene. They further illustrate the complexity of the response mounted against the parasite, which places MASP1 products in the regulatory crossroad between the innate and adaptive arms of the immunological system, modulating leprosy susceptibility.

Pyridoxine-dependent epilepsy (PDE) is a severe neonatal seizure disorder and is here modeled in aldh7a1 -/- zebrafish. Mutant larvae display spontaneous.., 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.

Lineage tracing of specific populations of progenitor cells provides crucial information about developmental programs. Four members of the Dlx homeobox gene family, Dlx1,2, 5 and 6, are involved in the specification of γ-aminobutyric acid (GABA)ergic neurons in the vertebrate forebrain. Orthologous genes in mammals and teleost show similarities in expression patterns and transcriptional regulation mechanisms. We have used lineage tracing to permanently label dlx-expressing cells in the zebrafish and have characterized the progeny of these cells in the larva and in the juvenile and adult brain. We have found that dlx1a/2a and dlx5a/6a expressing progenitors give rise, for the most part, to small populations of cells which constitute only a small proportion of GABAergic cells in the adult brain tissue. Moreover, some of the cells do not acquire a neuronal phenotype suggesting that, regardless of the time a cell expresses dlx genes in the brain, it can potentially give rise to cells other than neurons. In some instances, labeling larval dlx5a/6a-expressing cells, but not dlx1a/2a-expressing cells, results in massively expanding, widespread clonal expansion throughout the adult brain. Our data provide a detailed lineage analysis of the dlx1a/2a and dlx5a/6a expressing progenitors in the zebrafish brain and lays the foundation for further characterization of the role of these transcription factors beyond the specification of GABAergic neurons.

Objective: To evaluate serum concentrations of mannose-binding lectin (MBL) in women presenting with different human papillomavirus (HPV)-associated cervical lesions. Subjects and Methods: A total of 364 women, who underwent screening for cervical cancer or treatment at the Erasto Gaertner Cancer Hospital (HEG), Curitiba, Brazil, were enrolled in the study. Based on the latest cervical colposcopy-guided biopsy results, the women were divided into 4 groups: cervical intraepithelial neoplasia CIN-I (n = 54), CIN-II (n = 72), CIN-III (n = 145), and invasive cancer (n = 93). A time-resolved immunofluorometric assay was used to measure the MBL concentrations in serum. The statistical analysis was done using GraphPad Prism 6.0. Comparisons were performed by Kruskal-Wallis and Mann-Whitney tests and analyzed by χ2 test; continuous variables are presented as medians and categorical variables as frequencies. Results: The median MBL concentrations in decreasing order were as follows: invasive cancer: 1,452 ng/mL, CIN-I: 1,324 ng/mL, CIN-II: 1,104 ng/mL, and CIN-III 1,098 ng/mL. However, no statistical significance was found among the 4 groups with HPV-associated lesions (p = 0.11). Equally, the MBL levels did not show a significant association between the age of the patients and the severity of the cervical lesions (p = 0.68). No statistical significance was found in the median values of MBL or in the status of MBL deficient (1,000 ng/mL) among the women in each group (p = 0.77). Conclusion: In this study, there was no statistically significant difference in MBL serum levels among the groups with CIN. Hence MBL serum concentration appeared not to have influenced the progression of HPV-related preinvasive cervical lesions into invasive cancer.

Multilex PCR-SSP for genotyping of the following 5 SNPs of Human MASP1 gene: Intron 1 rs7609662*G>A rs13064994*C>T Exon 12 3’-untranslated: rs72549262*C>G rs1109452*C>T rs850314*G>A

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. TheDlxhomeobox genes are involved in the development of nervous system, neural crest, brachial arches and developing appendages.Dlxgenes also take part in neuronal migration and differentiation during development, more precisely, in the migration and differentiation of GABAergic neurons. Functional analysis ofdlxgenes 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 brain of adult zebrafish makes them a good model for the visualization of mechanisms involvingdlxgenes during adulthood in physiological conditions and during regeneration of the nervous system. We have identified the adult brain regions where transcripts ofdlx1a, dlx2a, dlx5aanddlx6agenes are normally found and have confirmed that within telencephalic domains, there is high overlapping expression of the fourdlxparalogs 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 thedlx5a/6abigene may have a neural stem cell identity by co-localizing with a Sox2 antibody. Furthermore, investigations in a response to stab wound lesions, have demonstrated a possible participation of thedlx5a/6abigene, most likely, ofdlx5aduring the regeneration of the adult zebrafish brain. These data suggest a possible participation ofdlx-expressing cells during brain regeneration in adult zebrafish and also provide information on the role ofdlxgenes under normal physiological conditions in adults.

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 < 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 < 0.0001, medians 18,240 vs. 44,030 ng/ml, respectively) and HIV/HCV coinfected (p < 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.