Evidence for spontaneous regulation of the humoral IgM anti-GM1 autoimmune response by IgG antibodies in multifocal motor neuropathy patients.

BACKGROUND AND AIMS: Multifocal motor neuropathy (MMN) is a peripheral nerve disorder characterized by slow progressive distal asymmetric weakness with minimal or no sensory impairment. Currently, a vast evidence supports a direct pathogenic role of IgM anti-GM1 antibodies on disease pathogenesis. Patients with MMN seropositive for GM1-specific IgM antibodies have significantly more weakness, disability and axon loss than patients without these antibodies. During the screening for IgM anti-GM1 antibodies in a cohort of patients with neuropathy we noticed an absence or significant reduction of natural IgM anti-GM1 autoreactivity in some patients with MMN, suggesting a mechanism of self-control of autoreactivity. We aim to understand the lack of natural reactivity against GM1 in MMN patients. METHODS: The presence of free IgM anti-GM1 reactivity or its complex to blocking IgG was analysed by combining high performance thin layer chromatography-immunostaining, soluble binding inhibition assays, Protein-G or GM1-affinity columns and dot blot assays. RESULTS: We identified in MMN patients an immunoregulation of IgM anti-GM1 antibodies mediated by IgG immunoglobulins characterized by: (i) lack of natural IgM anti-GM1 autoreactivity as a result of a immunoregulatory IgG-dependent mechanism; (ii) presence of natural and disease-associated IgM anti-GM1/IgG blocking Ab complexes in sera; and (iii) high levels of IgG blocking against natural IgM anti-GM1 antibodies (Abs. INTERPRETATION: Our observations unmask a spontaneous IgG-dependent mechanism of immunoregulation against IgM anti-GM1 antibodies that could explain, in part, fluctuations in the usually slowly progressive clinical course that characterizes the disease and, at the same time, allows the identification of an autoimmune response against GM1 ganglioside in seronegative patients.

Gangliosides in nervous system development, regeneration, and pathologies.

Gangliosides, sialic acid-containing sphingolipids, are major constituents of neuronal membranes. According to the number of sialic acids and the structure of the oligosaccharide chain, gangliosides can be classified as simple or complex and grouped in different ganglio-series. Hundreds of gangliosides have been identified in vertebrate cells, with different expression patterns during development and related to several physiological processes, especially in the nervous system. While GD3 and its O-acetylated form, 9acGD3, are highly expressed in early developmental stages, GM1, GD1a, GD1b, and GT1b are the most abundant ganglioside species in the mature nervous system. Mutations in enzymes involved in ganglioside metabolism can lead to the accumulation of specific species, a condition termed gangliosidosis and usually marked by severe neurological impairment. Changes in ganglioside levels have also been described in several neurodegenerative diseases, such as Alzheimer's and Parkinson's. In this review, we summarized recent information about the roles of GD3, 9acGD3, GM1, GD1a, GD1b, GT1b, and other ganglioside species in nervous system development and regeneration, as well as clinical trials evaluating possible therapeutic applications of these molecules.

Effects of ganglioside GM1 and erythropoietin on spinal cord injury in mice: Functional and immunohistochemical assessments.

OBJECTIVES: To evaluate the functional and immunohistochemical effects of ganglioside GM1 and erythropoietin following experimental spinal cord injury. METHODS: Thirty-two male BALB/c mice were subjected to experimental spinal cord injury using the NYU Impactor device and were randomly divided into the following groups: GM1 group, receiving standard ganglioside GM1 (30 mg/kg); erythropoietin group, receiving erythropoietin (1000 IU/kg); combination group, receiving both drugs; and control group, receiving saline (0.9%). Animals were evaluated according to the Basso Mouse Scale (BMS) and Hindlimb Mouse Function Score (MFS). After euthanasia, the immunohistochemistry of the medullary tissue of mice was analyzed. All animals received intraperitoneal treatment. RESULTS: The GM1 group had higher BMS and MFS scores at the end of the experiment when compared to all other groups. The combination group had higher BMS and MFS scores than the erythropoietin and control groups. The erythropoietin group had higher BMS and MFS scores than the control group. Immunohistochemical tissue analysis showed a significant difference among groups. There was a significant increase in myelinated axons and in the myelinated axon length in the erythropoietin group when compared to the other intervention groups (p < 0.01). CONCLUSIONS: Erythropoietin and GM1 have therapeutic effects on axonal regeneration in mice subjected to experimental spinal cord injury, and administration of GM1 alone had the highest scores on the BMS and MFS scales.

Effects of ganglioside GM1 and erythropoietin on spinal cord injury in mice: Functional and immunohistochemical assessments

ABSTRACT Objectives: To evaluate the functional and immunohistochemical effects of ganglioside GM1 and erythropoietin following experimental spinal cord injury. Methods: Thirty-two male BALB/c mice were subjected to experimental spinal cord injury using the NYU Impactor device and were randomly divided into the following groups: GM1 group, receiving standard ganglioside GM1 (30 mg/kg); erythropoietin group, receiving erythropoietin (1000 IU/kg); combination group, receiving both drugs; and control group, receiving saline (0.9%). Animals were evaluated according to the Basso Mouse Scale (BMS) and Hindlimb Mouse Function Score (MFS). After euthanasia, the immunohistochemistry of the medullary tissue of mice was analyzed. All animals received intraperitoneal treatment. Results: The GM1 group had higher BMS and MFS scores at the end of the experiment when compared to all other groups. The combination group had higher BMS and MFS scores than the erythropoietin and control groups. The erythropoietin group had higher BMS and MFS scores than the control group. Immunohistochemical tissue analysis showed a significant difference among groups. There was a significant increase in myelinated axons and in the myelinated axon length in the erythropoietin group when compared to the other intervention groups (p < 0.01). Conclusion: Erythropoietin and GM1 have therapeutic effects on axonal regeneration in mice subjected to experimental spinal cord injury, and administration of GM1 alone had the highest scores on the BMS and MFS scales.

GM1 gangliosidosis: a case report / Gangliosidose GM1: um relato de caso

RESUMEN La gangliosidosis GM1 es un trastorno lisosomal caracterizada por la acumulación de gangliósido GM1 (glucoesfingolípido) en el sistema nervioso central (SNC) y visceral, debido a la deficiencia de la enzima beta-galactosidase (hidrolasa lisosomal). Afecta principalmente al SNC y las vísceras y produce importantes anomalías esqueléticas, que a menudo ocurren con la presencia de linfocitos vacuolados en la muestra de la sangre periférica o médula ósea. Tiene tres formas de presentación, lo que dificulta aún más su identificación debido al amplio espectro clínico. El presente estudio tiene como objetivo describir un caso de gangliosidosis GM1 en un paciente masculino, nacido a las 38 semanas. Hasta el momento, no existe un tratamiento efectivo para la gangliosidosis GM1, es decir, el portador de la enfermedad solo recibe medidas sintomáticas y paliativas. Por tanto, el diagnóstico precoz de la enfermedad es de suma importancia, ya que su única forma de prevención, actualmente, es a través del consejo genético.

Testosterone-loaded GM1 micelles targeted to the intracellular androgen receptor for the specific induction of genomic androgen signaling.

Androgens play a central role in homeostatic and pathological processes of the prostate gland. At the cellular level, testosterone activates both the genomic signaling pathway, through the intracellular androgen receptor (AR), and membrane-initiated androgen signaling (MIAS), by plasma membrane receptors. We have previously shown that the activation of MIAS induces uncontrolled proliferation and fails to stimulate the beneficial immunomodulatory effects of testosterone in prostatic cells, becoming necessary to investigate if genomic signaling mediates homeostatic effects of testosterone. However, the lack of specific modulators for genomic androgen signaling has delayed the understanding of this mechanism. In this article, we demonstrate that monosialoganglioside (GM1) micelles are capable of delivering testosterone into the cytoplasm to specifically activate genomic signaling. Stimulation with testosterone-loaded GM1 micelles led to the activation of androgen response element (ARE)-regulated genes in vitro as well as to the recovery of normal prostate size and histology after castration in mice. In addition, these micelles avoided MIAS, as demonstrated by the absence of rapid signaling pathway activation and the inability to induce uncontrolled cell proliferation. In conclusion, our results validate a novel tool for the specific activation of genomic androgen signaling and demonstrate the importance of selective pathway activation in androgen-mediated proliferation.

Clinical findings in Brazilian patients with adult GM1 gangliosidosis.

GM1 gangliosidosis is a lysosomal storage disorder caused by ß-galactosidase deficiency. To date, prospective studies for GM1 gangliosidosis are not available, and only a few have focused on the adult form. This retrospective cross-sectional study focused on clinical findings in Brazilian patients with the adult form of GM1 gangliosidosis collected over 2 years. Ten subjects were included in the study. Eight were males and two females, with median age at diagnosis of 11.5 years (IQR, 4-34 years). Short stature and weight below normal were seen in five out of the six patients with data available. Radiological findings revealed that the most frequent skeletal abnormalities were beaked vertebrae, followed by hip dysplasia, and platyspondyly. Neurological examination revealed that dystonia and swallowing problems were the most frequently reported. None of the patients presented hyperkinesia, truncal hypertonia, Parkinsonism, or spinal cord compression. Clinical evaluation revealed impairment in activities of cognitive/intellectual development and behavioral/psychiatric disorders in all nine subjects with data available. Language/speech impairment (dysarthria) was found in 8/9 patients, fine motor and gross motor impairments were reported in 7/9 and 5/9 patients, respectively. Impairment of cognition and daily life activities were seen in 7/9 individuals. Our findings failed to clearly identify typical early or late alterations presented in GM1 gangliosidosis patients, which confirms that it is a very heterogeneous condition with wide phenotypic variability. This should be taken into account in the evaluation of future therapies for this challenging condition.

Antidiarrheal activity of α-terpineol in mice.

Diarrhea is one of the leading causes of infant death in the world accounting for high child mortality rate. It is also present in different pathophysiologies related to several etiological agents. The aim of this study is to investigate the antidiarrheal effect of α -Terpineol (α-TPN) in different diarrhea models in rodents. The antidiarrheal effect of α-TPN in the treatment of acute diarrhea and enteropooling induced by castor oil or PGE2 in Swiss mice pretreated orally with saline (NaCl 0.9%), Loperamide (5 mg/kg) and α-TPN (6.25, 12.5, 25 and 50 mg/kg) was analyzed. Additionally, parameters of severity, total weight of faeces and post-treatment for 4 h were evaluated. Modulation of the opioid and cholinergic pathways was performed and intestinal transit model using activated charcoal as marker was also used. The effect of α-TPN on secretory diarrhea was investigated using the model of fluid secretion in intestinal loops isolated from cholera toxin-treated mice. α-TPN showed antidiarrheal effect (*p < 0.05), reducing the total stool amount (*55%, *48%, *44%, *24%) and diarrheal (*47%, *66%; *56%, 10%) respectively for the doses tested. All doses investigated in the enteropooling test presented significant changes (*46%, *78%, *66%, *41% respectively) in relation to the control. α-TPN through the muscarinic pathway reduced the gastrointestinal transit (*31%), besides inhibiting PGE2-induced diarrhea (*39%). α-TPN also reduced fluid formation and loss of Cl- ions, by interacting directly with GM1 receptors and cholera toxin, thus increasing the uptake of intestinal fluids. The results suggest an anti-diarrheal activity of α-TPN due to its anticholinergic action, ability to block PGE2 and GM1 receptors and interaction with cholera toxin in secretory diarrhea, making it a promising candidate drug for the treatment of diarrheal diseases.

Direct visualization of the lateral structure of giant vesicles composed of pseudo-binary mixtures of sulfatide, asialo-GM1 and GM1 with POPC.

We compared the lateral structure of giant unilamellar vesicles (GUVs) composed of three pseudo binary mixtures of different glycosphingolipid (GSL), i.e. sulfatide, asialo-GM1 or GM1, with POPC. These sphingolipids possess similar hydrophobic residues but differ in the size and charge of their polar head group. Fluorescence microscopy experiments using LAURDAN and DiIC18 show coexistence of micron sized domains in a molar fraction range that depends on the nature of the GSLs. In all cases, experiments with LAURDAN show that the membrane lateral structure resembles the coexistence of solid ordered and liquid disordered phases. Notably, the overall extent of hydration measured by LAURDAN between the solid ordered and liquid disordered membrane regions show marked similarities and are independent of the size of the GSL polar head group. In addition, the maximum amount of GSL incorporated in the POPC bilayer exhibits a strong dependence on the size of the GSL polar head group following the order sulfatide>asialo-GM1>GM1. This observation is in full harmony with previous experiments and theoretical predictions for mixtures of these GSL with glycerophospholipids. Finally, compared with previous results reported in GUVs composed of mixtures of POPC with the sphingolipids cerebroside and ceramide, we observed distinctive curvature effects at particular molar fraction regimes in the different mixtures. This suggests a pronounced effect of these GSL on the spontaneous curvature of the bilayer. This observation may be relevant in a biological context, particularly in connection with the highly curved structures found in neural cells.

Asociación de melanocitosis dérmica con enfermedades lisosomales / Association of dermal melanocytosis with lysosomal storage diseases

Introducción: la melanocitosis dérmica incluye un espectro de lesiones de piel que abarca la mancha mongólica, entre otras lesiones. Las enfermedades lisosomales son afecciones de base genética que se caracterizan por la acumulación de metabolitos insolubles parciamente degradados en los compartimentos lisosomales, debido a una determinada deficiencia enzimática. Las deficiencias de b-galactosidasa y de a-L-iduronidasa provocan la gangliosidosis GM1 y la mucopolisacaridosis tipo I respectivamente, ambas presentando similitudes en su presentación clínica. La asociación de la melanocitosis dérmica con las enfermedades lisosomales es poco común y mal entendida. Objetivo: reportar dos pacientes con esta rara asociación. Casos clínicos: dos varones de 3 y 9 meses sin antecedentes prenatales ni perinatales a destacar y antecedentes de infecciones respiratorias reiteradas. Se presentaron con retraso del desarrollo, hipotonía central y trastorno deglutorio. Al examen se constató hepatomegalia, fascies tosca y melanosis dérmica extensa. Los estudios permitieron diagnosticar al paciente de 3 meses mucopolisacaridosis Tipo I y al de 9 meses gangliosidosis GM1. Discusión: no se conoce exactamente la causa de esta asociación. Se plantea que sería el resultado de la acumulación de gangliósidos y heparán sulfato que estimularían al receptor del factor de crecimiento neuronal de tipo tirosinquinasa, deteniendo la migración de los melanocitos en la dermis. Por lo tanto la melanosis dérmica aberrante, en el contexto clínico adecuado, puede ser un signo que facilite el diagnóstico de una enfermedad lisosomal subyacente.

Introduction: dermal melanocytosis includes a spectrum of skin lesions, mongolian spots being one of them. Lysosomal storage diseases are characterized by the accumulation of partially degraded insoluble metabolites in lysosomal compartments due to enzyme deficiency. Deficiency in b-galactosidosisis is the cause of GM1 gangliosidosis and deficiency in a-L-iduronidasa of mucopolysaccharidosis type I. Both have similar clinical presentations. Association of dermal melanocytosis and lysosomal storage diseases is uncommon and misunderstood. Objective: to report the case of two patients with this rare association. Clinical cases: the study presents two boys, 3 and 9 months old, with no remarkable family, pregnancy or delivery history. Both had repeated respiratory tract infections. They presented with developmental delay, central hypotonia and swallowing disorder. Upon clinical examination they showed hepatomegaly, coarse facies and extensive dermal melanocytosis. They were diagnosed with GM1 gangliosidosis and mucopolysaccharidosis type I. Discussion: the cause of this association is not well known. It is hypothesized that accumulation of gangliosides and heparan sulfates stimulates tyrosine-kinase neuronal growth factor receptor, stopping dermal melanocytosis migration. Therefore extensive dermal melanocytosis, in an appropriate clinical setting, may contribute to diagnosing lysosomal storage diseases.

Asociación de melanocitosis dérmica con enfermedades lisosomales / Association of dermal melanocytosis with lysosomal storage diseases

Introducción: la melanocitosis dérmica incluye un espectro de lesiones de piel que abarca la mancha mongólica, entre otras lesiones. Las enfermedades lisosomales son afecciones de base genética que se caracterizan por la acumulación de metabolitos insolubles parciamente degradados en los compartimentos lisosomales, debido a una determinada deficiencia enzimática. Las deficiencias de b-galactosidasa y de a-L-iduronidasa provocan la gangliosidosis GM1 y la mucopolisacaridosis tipo I respectivamente, ambas presentando similitudes en su presentación clínica. La asociación de la melanocitosis dérmica con las enfermedades lisosomales es poco común y mal entendida. Objetivo: reportar dos pacientes con esta rara asociación. Casos clínicos: dos varones de 3 y 9 meses sin antecedentes prenatales ni perinatales a destacar y antecedentes de infecciones respiratorias reiteradas. Se presentaron con retraso del desarrollo, hipotonía central y trastorno deglutorio. Al examen se constató hepatomegalia, fascies tosca y melanosis dérmica extensa. Los estudios permitieron diagnosticar al paciente de 3 meses mucopolisacaridosis Tipo I y al de 9 meses gangliosidosis GM1. Discusión: no se conoce exactamente la causa de esta asociación. Se plantea que sería el resultado de la acumulación de gangliósidos y heparán sulfato que estimularían al receptor del factor de crecimiento neuronal de tipo tirosinquinasa, deteniendo la migración de los melanocitos en la dermis. Por lo tanto la melanosis dérmica aberrante, en el contexto clínico adecuado, puede ser un signo que facilite el diagnóstico de una enfermedad lisosomal subyacente.

Exogenous GM1 ganglioside increases accumbal BDNF levels in rats.

Gangliosides are compounds that are abundant throughout the CNS, participating actively in neuroplasticity. We previously described that exogenous GM1 ganglioside pretreatment enhances the rewarding properties of cocaine, evidenced by a lower number of sessions and/or dosage necessary to induce conditioned place preference (CPP). Since GM1 pretreatment did not modify cocaine's pharmacokinetic parameters, we suspected that the increased rewarding effect found might be mediated by BDNF, a neurotrophic factor closely related to cocaine addiction. This study was performed to investigate the possibility that GM1 may induce changes in BDNF levels in the nucleus accumbens (NAc), a core structure in the brain's reward circuitry, of rats submitted to three conditioning sessions with cocaine (10 mg/kg, i.p.). The results demonstrate that GM1 administration, which showed no rewarding effect by itself in the CPP, induced a significant increase of BDNF protein levels in the NAc, which may account for the increased rewarding effect of cocaine shown in the CPP paradigm.

β-Galactosidase Deficiency in Colombia: Report of 20 Patients Detected Using Dried Blood Spot Samples

Abstract β-Galactosidase (BGal) is the first enzyme involved in the catabolism of sphingolipids. Two pathologies have been directly associated with its deficiency: GM1 gangliosidosis and Morquio B. Morquio B is among the rarest types of mucopolysaccharidosis (MPS). We aim to document the β-galactosidase deficiency in Colombia. We evaluated leukocytes from 1492 healthy Colombian individuals and 923 patients, referred between 2005 and August 2014. Dried blood spot (DBS) samples from the same number of patients were evaluated. β-Galactosidase was measured with 4-methylumbelliferyl-β-d-galactoside. As a control enzyme, the total hexosaminidase activity was also evaluated. We identified 14 patients with GM1 gangliosidosis, 5 patients with Morquio B, and 1 patient with I-cell disease. We could establish a reference value for Bgal in Colombian leukocyte samples. GM1 gangliosidosis is the main pathology associated with a direct deficiency of BGal. The high number of patients found with MPS IVB indicates that there are patients who could be misdiagnosed due to an unawareness of the disease.

Gangliosidosis generalizada tipo 1 / Generalized gangliosidosis type 1

La gangliosidosis generalizada tipo 1 es una enfermedad de acúmulo lisosomal producida por mutaciones en el gen de la enzima b-galactosidasa, caracterizada fundamentalmente por toma del sistema nervioso central, la visceromegalia, disostosis ósea y dimorfismo facial. Se presenta el caso de un lactante varón, hijo de padres no consanguíneos, de 5 meses de edad, Apgar 6/8 debido a hipoxia neonatal, con historia de múltiples ingresos por enfermedad diarreica e infecciones respiratorias. Es remitido a la Consulta de Genética Clínica por retardo del desarrollo psicomotor, macrocráneo y hepatomegalia, además de máculas hipercrómicas en piel. En el examen físico se encontraron evidencias de una posible afectación por enfermedad metabólica lisosomal. Entre las enfermedades a descartar estaban la galactosialidosis, de características clínicas similares, y la enfermedad de Morquio, con diferente presentación clínica pero idéntico defecto enzimático

Generalized or GM 1 gangliosidosis is a lysosomal storage disease caused by mutations in the enzyme b-galactosidase gene, mainly characterized by affecting the central nervous system, visceromegalia, osseous dysostosis and facial dimorphism. This is the case of a male nursling born to non-consanguineous parents, 5 months of age, Apgar index of 6/8 due to neonatal hypoxia, with a history of several admissions to hospital because of diarrheal disease and respiratory infections. He was referred to the clinical genetic service since he presented with retarded psychomotor development, macrocrania and hepatomegalia, in addition to hyperchromic skin spots. The physical exam found evidence of possible effects by lysosomal metabolic disease. Among the diseases to be ruled out for the diagnosis were galactosialidosis of similar clinical characteristics and Morquio B disease with different clinical presentation but identical enzymatic deficiency

Tritrichomonas foetus displays classical detergent-resistant membrane microdomains on its cell surface.

Tritrichomonas foetus is a serious veterinary parasite that causes bovine trichomoniasis, a sexually transmitted disease that results in reproductive failure and considerable economic losses in areas that practice natural breeding. T. foetus is an extracellular parasite, which initially adheres to and infects the urogenital tract using a diverse array of surface glycoconjugates, including adhesins and extracellular matrix-binding molecules. However, the cellular mechanisms by which T. foetus colonizes mucosal surfaces and causes tissue damage are not well defined. Several studies have demonstrated the involvement of pathogen or host lipid rafts in cellular events that occur during pathogenesis, including adhesion, invasion and evasion of the immune response. In this study, we demonstrate that detergent-resistant membranes are present in the plasma membrane of T. foetus. We further demonstrate that microdomains are cholesterol-enriched and contain ganglioside GM1-like molecules. In addition, we demonstrate that lipid microdomains do not participate in T. foetus adhesion to host cells. However, the use of agents that disrupt and disorganize the plasma membrane indicated the involvement of the T. foetus lipid microdomains, in cell division and in the formation of endoflagellar forms. Our results suggest that trophozoites and endoflagellar forms present a different plasma membrane organization.

Procyanidins can interact with Caco-2 cell membrane lipid rafts: involvement of cholesterol.

Large procyanidins (more than three subunits) are not absorbed at the gastrointestinal tract but could exert local effects through their interactions with membranes. We previously showed that hexameric procyanidins (Hex), although not entering cells, interact with membranes modulating cell signaling and fate. This paper investigated if Hex, as an example of large procyanidins, can selectively interact with lipid rafts which could in part explain its biological actions. This mechanism was studied in both synthetic membranes (liposomes) and Caco-2 cells. Hex promoted Caco-2 cell membrane rigidification and dehydration, effects that were abolished upon cholesterol depletion with methyl-ß-cyclodextrin (MCD). Hex prevented lipid raft structure disruption induced by cholesterol depletion/redistribution by MCD or sodium deoxycholate. Supporting the involvement of cholesterol-Hex bonding in Hex interaction with lipid rafts, the absence of cholesterol markedly decreased the capacity of Hex to prevent deoxycholate- and Triton X-100-mediated disruption of lipid raft-like liposomes. Stressing the functional relevance of this interaction, Hex mitigated lipid raft-associated activation of the extracellular signal-regulated kinases (ERK) 1/2. Results support the capacity of a large procyanidin (Hex) to interact with membrane lipid rafts mainly through Hex-cholesterol bondings. Procyanidin-lipid raft interactions can in part explain the capacity of large procyanidins to modulate cell physiology.

Biofilm formation and binding specificities of CFA/I, CFA/II and CS2 adhesions of Enterotoxigenic Escherichia coli and CfaE-R181A mutant

Enterotoxigenic Escherichia coli (ETEC) strains are leading causes of childhood diarrhea in developing countries. Adhesion is the first step in pathogenesis of ETEC infections and ETEC pili designated colonization factor antigens (CFAs) are believed to be important in the biofim formation, colonization and host cell adhesions. As a first step, we have determined the biofilm capability of ETEC expressing various types of pili (CFA/I, CfaE-R181A mutant/ CfaE tip mutant, CFA/II and CS2). Further, enzyme-linked immunosorbent assay (ELISA) assay were developed to compare the binding specificity of CFA/I, CFA/II (CS1 - CS3) and CS2 of ETEC, using extracted pili and piliated bacteria. CFA/II strain (E24377a) as well as extracted pili exhibited significantly higher binding both in biofilm and ELISA assays compared to non piliated wild type E24377a, CFA/I and CS2 strains. This indicates that co-expression of two or more CS2 in same strain is more efficient in increasing adherence. Significant decrease in binding specificity of DH5αF'lacIq/∆cotD (CS2) strain and MC4100/pEU2124 (CfaE-R181A) mutant strain indicated the important contribution of tip proteins in adherence assays. However, CS2 tip mutant strain (DH5αF'lacIq/pEU5881) showed that this specific residue may not be important as adhesions in these strains. In summary, our data suggest that pili, their minor subunits are important for biofilm formation and adherence mechanisms. Overall, the functional reactivity of strains co expressing various antigens, particularly minor subunit antigen observed in this study suggest that fewer antibodies may be required to elicit immunity to ETEC expressing a wider array of related pili.

Gangliosidosis gml juvenil como causa de regresión en el neurodesarrollo: reporte de caso / Juvenile GM1 gangliosidosis as a cause of regression in neurodevelopment: a case report

La gangliosidosis GM1 es ocasionada por deficiencia en la actividad catalítica de la enzima lisosomal beta-galacto-sidasa, dando origen a la acumulación del esfingolípido conocido como gangliósido GM1. La enfermedad se manifiesta en forma generalizada, con trastornos neurológicos y visceromegalias. Reportamos un caso de presentación juvenil, masculino de 5 años con historia de pérdida de hitos del desarrollo motor, cognitivo y lenguaje en forma progresiva. Se diagnosticó gangliosidosis GM1 juvenil o tipo II luego del análisis de los estudios de laboratorio, neuroimágen y baja actividad enzimática de la beta-galactosidasa.

Gangliosidosis GM1 is due a deficiency of lysosomal acid beta-galactosidase which gives sphingolipids (GM1) accumulation. It has systemic compromise, mainly neurologic disease and organomegaly. Here, We report a 5-years old child with a juvenile presentation or type II, which is characterized by regression of neurodevelopment and progression to neurodegeneration. Based in his laboratory, neuroimaging and low enzymatic activity of beta-galactosidase a diagnosis of gangliosidoses GM1 was made.

Biofilm formation and binding specificities of CFA/I, CFA/II and CS2 adhesions of enterotoxigenic Escherichia coli and Cfae-R181A mutant.

Enterotoxigenic Escherichia coli (ETEC) strains are leading causes of childhood diarrhea in developing countries. Adhesion is the first step in pathogenesis of ETEC infections and ETEC pili designated colonization factor antigens (CFAs) are believed to be important in the biofim formation, colonization and host cell adhesions. As a first step, we have determined the biofilm capability of ETEC expressing various types of pili (CFA/I, CfaE-R181A mutant/CfaE tip mutant, CFA/II and CS2). Further, enzyme-linked immunosorbent assay (ELISA) assay were developed to compare the binding specificity of CFA/I, CFA/II (CS1 - CS3) and CS2 of ETEC, using extracted pili and piliated bacteria. CFA/II strain (E24377a) as well as extracted pili exhibited significantly higher binding both in biofilm and ELISA assays compared to non piliated wild type E24377a, CFA/I and CS2 strains. This indicates that co-expression of two or more CS2 in same strain is more efficient in increasing adherence. Significant decrease in binding specificity of DH5αF'lacI (q)/∆cotD (CS2) strain and MC4100/pEU2124 (CfaE-R181A) mutant strain indicated the important contribution of tip proteins in adherence assays. However, CS2 tip mutant strain (DH5αF'lacI (q)/pEU5881) showed that this specific residue may not be important as adhesions in these strains. In summary, our data suggest that pili, their minor subunits are important for biofilm formation and adherence mechanisms. Overall, the functional reactivity of strains co expressing various antigens, particularly minor subunit antigen observed in this study suggest that fewer antibodies may be required to elicit immunity to ETEC expressing a wider array of related pili.

Biofilm formation and binding specificities of CFA/I, CFA/II and CS2 adhesions of Enterotoxigenic Escherichia coli and CfaE-R181A mutant

Enterotoxigenic Escherichia coli (ETEC) strains are leading causes of childhood diarrhea in developing countries. Adhesion is the first step in pathogenesis of ETEC infections and ETEC pili designated colonization factor antigens (CFAs) are believed to be important in the biofim formation, colonization and host cell adhesions. As a first step, we have determined the biofilm capability of ETEC expressing various types of pili (CFA/I, CfaE-R181A mutant/ CfaE tip mutant, CFA/II and CS2). Further, enzyme-linked immunosorbent assay (ELISA) assay were developed to compare the binding specificity of CFA/I, CFA/II (CS1 - CS3) and CS2 of ETEC, using extracted pili and piliated bacteria. CFA/II strain (E24377a) as well as extracted pili exhibited significantly higher binding both in biofilm and ELISA assays compared to non piliated wild type E24377a, CFA/I and CS2 strains. This indicates that co-expression of two or more CS2 in same strain is more efficient in increasing adherence. Significant decrease in binding specificity of DH5F'lacIq/cotD (CS2) strain and MC4100/pEU2124 (CfaE-R181A) mutant strain indicated the important contribution of tip proteins in adherence assays. However, CS2 tip mutant strain (DH5F'lacIq/pEU5881) showed that this specific residue may not be important as adhesions in these strains. In summary, our data suggest that pili, their minor subunits are important for biofilm formation and adherence mechanisms. Overall, the functional reactivity of strains co expressing various antigens, particularly minor subunit antigen observed in this study suggest that fewer antibodies may be required to elicit immunity to ETEC expressing a wider array of related pili.