RESUMEN
The epidemiological association between exposure to fine particulate matter (PM2.5) and adverse health effects is well-known. Here we report the size distribution, metals content, endotoxin content, and biological activity of National Institute of Standards and Technology (NIST) Interim Reference Material (RM) PM2.5. Biological activity was measured in vitro by effects on cell viability and the release of four inflammatory immune mediators, from human A549 alveolar epithelial cells or murine RAW264.7 monocytes. A dose range covering three orders of magnitude (1-1000µg/mL) was tested, and biological activity was compared to an existing Standard Reference Material (SRM) for urban PM (NIST SRM 1648). Robust release of IL-8 and MCP-1 from A549 cells was observed in response to IRM PM2.5 exposures. Significant TNF-α, but not IL-6, secretion from RAW264.7 cells was observed in response to both IRM PM2.5 and SRM 1648 particle types. Cytokine or chemokine release at high doses often occurred in the presence of cytotoxicity, likely as a result of externalization of preformed mediator. Our results are consistent with a local cytotoxic and pro-inflammatory mechanism of response to exposure to inhaled ambient PM2.5 and reinforce the continued relevance of in vitro assays for mechanistic research in PM toxicology. Our study furthers the goal of developing reference samples of environmentally relevant particulate matter of various sizes that can be used for hypothesis testing by multiple investigators.
Asunto(s)
Contaminantes Atmosféricos/normas , Material Particulado/normas , Contaminantes Atmosféricos/química , Contaminantes Atmosféricos/toxicidad , Animales , Línea Celular , Línea Celular Tumoral , Supervivencia Celular/efectos de los fármacos , Citocinas/metabolismo , Endotoxinas/análisis , Humanos , Metales/análisis , Ratones , Tamaño de la Partícula , Material Particulado/química , Material Particulado/toxicidad , Estándares de ReferenciaRESUMEN
A major challenge for the treatment of many central nervous system (CNS) disorders is the lack of convenient and effective methods for delivering biological agents to the brain. Mucopolysaccharidosis II (Hunter syndrome) is a rare inherited lysosomal storage disorder resulting from a deficiency of iduronate-2-sulfatase (I2S). I2S is a large, highly glycosylated enzyme. Intravenous administration is not likely to be an effective therapy for disease-related neurological outcomes that require enzyme access to the brain cells, in particular neurons and oligodendrocytes. We demonstrate that intracerebroventricular and lumbar intrathecal administration of recombinant I2S in dogs and nonhuman primates resulted in widespread enzyme distribution in the brain parenchyma, including remarkable deposition in the lysosomes of both neurons and oligodendrocytes. Lumbar intrathecal administration also resulted in enzyme delivery to the spinal cord, whereas little enzyme was detected there after intraventricular administration. Mucopolysaccharidosis II model is available in mice. Lumbar administration of recombinant I2S to enzyme deficient animals reduced the storage of glycosaminoglycans in both superficial and deep brain tissues, with concurrent morphological improvements. The observed patterns of enzyme transport from cerebrospinal fluid to the CNS tissues and the resultant biological activity (a) warrant further investigation of intrathecal delivery of I2S via lumbar catheter as an experimental treatment for the neurological symptoms of Hunter syndrome and (b) may have broader implications for CNS treatment with biopharmaceuticals.
Asunto(s)
Sistema Nervioso Central/efectos de los fármacos , Terapia de Reemplazo Enzimático/métodos , Iduronato Sulfatasa/uso terapéutico , Mucopolisacaridosis II/tratamiento farmacológico , Animales , Sistema Nervioso Central/metabolismo , Sistema Nervioso Central/patología , Perros , Humanos , Iduronato Sulfatasa/administración & dosificación , Iduronato Sulfatasa/genética , Inmunohistoquímica , Inyecciones Espinales , Radioisótopos de Yodo , Lisosomas/metabolismo , Macaca fascicularis , Ratones , Ratones Noqueados , Mucopolisacaridosis II/genética , Mucopolisacaridosis II/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Oligodendroglía/efectos de los fármacos , Oligodendroglía/metabolismo , Oligodendroglía/patología , Tomografía de Emisión de Positrones , Proteínas Recombinantes/administración & dosificación , Proteínas Recombinantes/farmacocinética , Proteínas Recombinantes/uso terapéutico , Especificidad de la Especie , Médula Espinal/efectos de los fármacos , Médula Espinal/metabolismo , Médula Espinal/patología , Distribución TisularRESUMEN
BACKGROUND: Complement C2 deficiency is the most common genetically determined complete complement deficiency and is associated with a number of diseases. Most prominent are the associations with recurrent serious infections in young children and the development of systemic lupus erythematosus (SLE) in adults. The links with these diseases reflect the important role complement C2 plays in both innate immunity and immune tolerance. Infusions with normal fresh frozen plasma for the treatment of associated disease have demonstrated therapeutic effects but so far protein replacement therapy has not been evaluated. RESULTS: Human complement C2 was cloned and expressed in a mammalian cell line. The purity of recombinant human C2 (rhC2) was greater than 95% and it was characterized for stability and activity. It was sensitive to C1s cleavage and restored classical complement pathway activity in C2-deficient serum both in a complement activation ELISA and a hemolytic assay. Furthermore, rhC2 could increase C3 fragment deposition on the human pathogen Streptococcus pneumoniae in C2-deficient serum to levels equal to those with normal serum. CONCLUSIONS: Taken together these data suggest that recombinant human C2 can restore classical complement pathway activity and may serve as a potential therapeutic for recurring bacterial infections or SLE in C2-deficient patients.
Asunto(s)
Complemento C2/metabolismo , Síndromes de Inmunodeficiencia/genética , Lupus Eritematoso Sistémico/genética , Proteínas Recombinantes/metabolismo , Infecciones Estreptocócicas/genética , Streptococcus pneumoniae/inmunología , Adulto , Línea Celular Transformada , Niño , Complemento C1/inmunología , Complemento C1/metabolismo , Complemento C2/genética , Complemento C2/uso terapéutico , Complemento C3/inmunología , Complemento C3/metabolismo , Vía Clásica del Complemento/efectos de los fármacos , Humanos , Síndromes de Inmunodeficiencia/complicaciones , Síndromes de Inmunodeficiencia/tratamiento farmacológico , Lupus Eritematoso Sistémico/complicaciones , Lupus Eritematoso Sistémico/tratamiento farmacológico , Unión Proteica/efectos de los fármacos , Proteínas Recombinantes/genética , Proteínas Recombinantes/uso terapéutico , Recurrencia , Infecciones Estreptocócicas/complicaciones , Infecciones Estreptocócicas/tratamiento farmacológicoRESUMEN
BACKGROUND: Recent studies indicate that the composition of fine particulate matter [PM Asunto(s)
Contaminantes Atmosféricos/análisis
, Asma/epidemiología
, Zinc/análisis
, Adolescente
, Niño
, Preescolar
, Femenino
, Geografía
, Humanos
, Lactante
, Recién Nacido
, Masculino
, Maryland/epidemiología
, Modelos Teóricos
, Salud Urbana/estadística & datos numéricos
RESUMEN
Cryptosporidiosis in young children prompts local inflammation in the intestinal tract. We studied a cohort of young children with cryptosporidiosis to determine whether systemic inflammatory responses occur and, if so, to evaluate whether inflammation persists after infection. Cryptosporidiosis was associated with increased levels of interleukin-8 and tumor necrosis factor- alpha systemically, which persisted at 6 months after enrollment. The level of intestinal tumor necrosis factor- alpha was elevated at enrollment, but elevated levels did not persist. Worsening of malnutrition, particularly stunting, was observed after infection. The association of cryptosporidiosis, inflammation, and stunting in children with cryptosporidiosis warrants further evaluation.
Asunto(s)
Criptosporidiosis/metabolismo , Interferón gamma/metabolismo , Interleucinas/metabolismo , Receptores del Factor de Necrosis Tumoral/metabolismo , Antígenos de Protozoos/sangre , Estudios de Cohortes , Femenino , Humanos , Lactante , Interferón gamma/sangre , Masculino , Receptores del Factor de Necrosis Tumoral/sangreRESUMEN
Vibrio vulnificus is the leading cause of death in the United States associated with the consumption of raw seafood, particularly oysters. In epidemiological studies, primary septicemia and inflammation-mediated septic shock caused by V. vulnificus is strongly associated with liver disease, often in the context of chronic alcohol abuse. The present study was undertaken to determine whether clinical biomarkers of liver function or cellular oxidative stress are associated with peripheral blood mononuclear cell inflammatory cytokine responses to V. vulnificus. Levels of interleukin-1 beta (IL-1 beta), IL-6, IL-8, and tumor necrosis factor alpha elicited in response to V. vulnificus and measured in cell supernatants were not associated with the liver biomarkers aspartate aminotransferase (AST) or alanine aminotransferase (ALT) or the AST/ALT ratio. In contrast, reduced glutathione (GSH) levels were associated with the release of all four cytokines (IL-1 beta [R(2) = 0.382; P = 0.006], IL-6 [R(2) = 0.393; P = 0.005], IL-8 [R(2) = 0.487; P = 0.001], and TNF-alpha [R(2) = 0.292; P = 0.021]). Those individuals with below-normal GSH levels produced significantly less proinflammatory cytokines in response to V. vulnificus. We hypothesize that persons with markers for cellular oxidative stress have increased susceptibility to V. vulnificus septicemia.