RESUMEN
A total of 16 Taenia multiceps isolates collected from naturally infected sheep or goats in Gansu Province, China were characterized by sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) gene. The complete cox1 gene was amplified for individual T. multiceps isolates by PCR, ligated to pMD18T vector, and sequenced. Sequence analysis indicated that out of 16 T. multiceps isolates 10 unique cox1 gene sequences of 1,623 bp were obtained with sequence variation of 0.12-0.68%. The results showed that the cox1 gene sequences were highly conserved among the examined T. multiceps isolates. However, they were quite different from those of the other Taenia species. Phylogenetic analysis based on complete cox1 gene sequences revealed that T. multiceps isolates were composed of 3 genotypes and distinguished from the other Taenia species.
Asunto(s)
Animales , China , Análisis por Conglomerados , Cisticercosis/parasitología , ADN de Helmintos/química , ADN Mitocondrial/química , Complejo IV de Transporte de Electrones/genética , Variación Genética , Enfermedades de las Cabras/parasitología , Cabras , Filogenia , Reacción en Cadena de la Polimerasa , Subunidades de Proteína/genética , Análisis de Secuencia de ADN , Ovinos , Enfermedades de las Ovejas/parasitología , Taenia/clasificaciónRESUMEN
The excretory-secretory products (ESP) released by muscle stage of Trichinella spiralis have been suggested to be involved in nurse cell formation. However, the molecular mechanisms by which ESP modulate nurse cell formation remain unclear. In the present study, the ability of ESP of muscle larvae of T. spiralis (ML-ESP) to influence the proliferation and differentiation of murine myoblasts and the mechanisms were evaluated in vitro using C2C12 myoblast cell line, which were incubated for various times under grow or differentiation culture medium containing various concentrations of ML-ESP. The results indicated that ML-ESP promoted myoblast proliferation in a dose-dependent manner and increased the expression of the cell-cycle regulator cyclin D1 as well as that of proliferating cell nuclear antigen (PCNA). Conversely, ML-ESP inhibited the differentiation of these cells, which was evidenced by a reduction in the levels of MHC and MRFs expression (MyoD and myogenin) as well as that of p21. In addition, ML-ESP also inhibited the phosphorylation of p38 MAPK in differentiating C2C12 myoblast. Taken together, these results imply that certain critical mediators contained in ML-ESP inhibit myogenesis through enhancing skeletal myoblasts proliferation and down-regulating the expression of MRFs as well as involving p38 MAPK signalling pathway, which provides insight into the mechanisms utilised by T. spiralis to interfere normal wound repair in infected muscle cells and affect nurse cell formation.
Asunto(s)
Diferenciación Celular/efectos de los fármacos , Proteínas del Helminto/metabolismo , Mioblastos/fisiología , Trichinella spiralis/patogenicidad , Factores de Virulencia/metabolismo , Animales , Antígenos Helmínticos , Ciclo Celular/efectos de los fármacos , Línea Celular , Perfilación de la Expresión Génica , Larva/patogenicidad , Ratones , Mioblastos/efectos de los fármacosRESUMEN
Trichinella spiralis is a zoonotic nematode and food borne parasite and infection with T. spiralis leads to suppression of the host immune response and other immunopathologies. The excretory/secretory (ES) products of T. spiralis play important roles in the process of immunomodulation. However, the mechanisms and related molecules are unknown. Macrophages, a target for immunomodulation by the helminth parasite, play a critical role in initiating and modulating the host immune response to parasite infection. In this study, we examined the effect of ES products from different stages of T. spiralis on modulating J774A.1 macrophage activities. ES products from different stages of T. spiralis reduced the capacity of macrophages to express pro-inflammatory cytokines (tumor necrosis factor α, interleukin-1ß , interleukin-6 , and interleukin-12) in response to lipopolysaccharide (LPS) challenge. However, only ES products from 3-day-old adult worms and 5-day-old adult worms/new-born larvae significantly inhibited inducible nitric oxide synthase gene expression in LPS-induced macrophages. In addition, ES products alone boosted the expression of anti-inflammatory cytokines interleukin-10 and transforming growth factor-ß and effector molecule arginase 1 in J774A.1 macrophages. Signal transduction studies showed that ES products significantly inhibited nuclear factor-κB translocation into the nucleus and the phosphorylation of both extracellular signal-regulated protein kinase 1/2 and p38 mitogen-activated protein kinase in LPS-stimulated J774A.1 macrophages. These results suggest that ES products regulate host immune response at the macrophage level through inhibition of pro-inflammatory cytokines production and induction of macrophage toward the alternative phenotype, which maybe important for worm survival and host health.
Asunto(s)
Medios de Cultivo Condicionados/farmacología , Citocinas/metabolismo , Larva/metabolismo , Macrófagos/metabolismo , Trichinella spiralis/metabolismo , Transporte Activo de Núcleo Celular/efectos de los fármacos , Animales , Línea Celular , Núcleo Celular/metabolismo , Supervivencia Celular/efectos de los fármacos , Citocinas/genética , Expresión Génica/efectos de los fármacos , Regulación de la Expresión Génica , Interacciones Huésped-Parásitos , Inflamación/inducido químicamente , Inflamación/metabolismo , Lipopolisacáridos , Macrófagos/efectos de los fármacos , Macrófagos/enzimología , Ratones , Proteínas Quinasas Activadas por Mitógenos/metabolismo , FN-kappa B/metabolismo , Óxido Nítrico Sintasa de Tipo II/metabolismo , Fosforilación , Ratas , Ratas WistarRESUMEN
Protoscoleces of Taenia multiceps were collected from the naturally infected sheep and total RNA was extracted. Specific primers were designed according to TaHe2-D11 mRNA sequence and T. multiceps thioredoxin peroxidase gene (TmTPx) was amplified by RT-PCR. PCR products were ligated into pMD18-T vector and transformed to E. coli DH5alpha. The recombinant plasmids were identified by restriction digestion and sequencing. A 614 bp cDNA was amplified. The TmTPx open reading frame (591 bp) encoded a 196-amino acid protein with Mr 21,690, pI 7.61. Bioinformatics analysis indicated that TmTPx had a typical 2-Cys Prx conserved domain. Phylogenetic tree revealed that T. multiceps had the closest relationship to T. asiatica, followed by T. solium and T. crassiceps, E. granulosus and E. multilocularis.