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1.
The cell-mediated response in BALB/c mice infected either by Trichinella pseudospiralis or Trichinella spiralis was compared at days 30–50 post-infection (muscle phase). The former species is non-encapsulated, whereas the latter is encapsulated in host muscles. The pattern of response against the two species was similar. Both species elicited TH0 or TH1/TH2 response, with the last one being dominant. Productions of interferon gamma (IFN-γ), interleukin (IL)-4 and IL-5 were observed after antigenic restimulation of splenocytes from infected mice. No significant difference was observed between the levels of response to concanavalin A (Con-A) by the splenocytes from both infected and non-infected animals. There was a significant increase in serum IgG1 and IgG2a. Flow cytometric analysis revealed a marked proliferative response of splenocytes from infected mice to worm antigens, dominated by B (CD19) lymphoblasts. Only a few helper (CD4+) and cytotoxic (CD8+) T lymphoblasts were present. This was confirmed by an up-regulation of CD69, with a dominant expression on B lymphoblasts. In conclusion, the minimal or lack of intense cellular response against T. pseudospiralis in muscles is likely not due to depression of cell-mediated immunity.  相似文献   

2.
The 53-kDa proteins in larval excretory and secretory (E-S) products were expressed from five Trichinella species (T. spiralis, T. britovi, T. nativa, T. pseudospiralis, and T. papuae), using the Escherichia coli expression system, and the antibody responses to the 53-kDa recombinant proteins in mice infected with Trichinella spp. were analyzed by Western blotting. The 53-kDa protein is conserved among the five Trichinella species, with >60% similarity in amino acid sequences. The 53-kDa recombinant proteins of T. spiralis and T. pseudospiralis reacted to sera from mice infected with T. spiralis and T. pseudospiralis at 8 days postinfection (p.i.), respectively. An antibody against the 53-kDa recombinant protein of T. spiralis recognized the 53-kDa protein in the crude extracts from adult worms and 30-day p.i. muscle larvae and E-S products from muscle larvae of T. spiralis but did not recognize any proteins from T. pseudospiralis. The sera from the mice infected with T. spiralis strongly reacted with the 53-kDa recombinant protein of T. spiralis but did not react with the 53-kDa recombinant proteins of T. britovi, T. nativa, T. pseudospiralis, and T. papuae. Similarly, the sera from mice infected with T. britovi, T. nativa, T. pseudospiralis, or T. papuae strongly reacted with the 53-kDa recombinant proteins of T. britovi, T. nativa, T. pseudospiralis, or T. papuae, respectively. These results showed that the 53-kDa recombinant proteins provide early and species-specific antibody responses in mice infected with Trichinella spp.  相似文献   

3.
The effect of Trichinella spiralis infection on the pharmacokinetic profile of orally administered albendazol has been investigated in mice during the intestinal phase of the disease. Swiss CD-1 mice were orally infected with 300 ± 50 muscle larvae of T. spiralis and then treated with albendazole (ABZ) formulated in hydroxy-propyl-beta-cyclodextrins at the dose of 10 mg/kg given orally on days 0, 5, 10 and 22 post-infection (p.i.). Blood samples were taken at 0.25, 0.5, 0.75, 1, 5, 6 and 24 h post-treatment (p.t.). Adult worm establishment as well as the histopathological alterations induced in the small intestine was assessed on days 0, 5, 10 and 22 p.i. The area under the blood concentrations to time curve (AUC) for ABZ sulphoxide was not significantly higher in infected mice than in control during the first step of intestinal infection (day 5 p.i.), whereas in the late step (day 10 p.i.), it was significantly lower. On day 22 p.i., the AUC showed similar values in both groups. The histopathological analysis showed a transient acute inflammatory reaction that varied from moderate to severe as the infection progressed from the early to the late intestinal stage. After intestinal infection, the inflammation was mild or absent with no signs of chronic effects. The histopathological studies correlated with the pharmacokinetics of ABZ and show that after transient inflammation induced by intestinal T. spiralis infection, the mucosa is restored to allow absorption of ABZ up to levels comparable to those observed in non-infected controls.  相似文献   

4.
Trichinella parasites with different epidemiological features still occur in Europe and four species of genus Trichinella have been identified: T. spiralis, T. britovi , T. nativa and T. pseudospiralis. Until now, two of them, T. spiralis and T. britovi, have been identified in Poland. In our studies we selected sequence coding for large mitochondrial rRNA (mt LrDNA) as a genetic marker and developed a sensitive LrDNA multiprimer PCR assay allowing for rapid identification of T. spiralis and T. britovi, parasites present in wild and domestic animals in Poland.  相似文献   

5.
A total of 36 sheep in groups of 4 were inoculated with 9 isolates of Trichinella and euthanized after 10 weeks. Thereafter, numbers of muscle larvae were determined in 13 different muscles/muscle groups. Muscle larvae were found in high numbers in all four sheep inoculated with T. spiralis, in lower numbers in two sheep inoculated with T. pseudospiralis (USA isolate), and in very low numbers in one sheep inoculated with T. pseudospiralis (USSR isolate) and one inoculated with T. britovi. In infections of high and moderate larval intensity, predilection sites of T. spiralis were the masseter muscles, the tongue, and the diaphragm and those of T. pseudospiralis were the masseter muscle and the neck. In low-intensity infections, muscle larvae were detected only in the diaphragm or in pooled muscle samples. For evaluation of the freeze tolerance of the different Trichinella species in sheep-muscle tissue, samples taken from the filet were stored at +5°, −5°, and −18 °C, respectively. After exposure for 1 and 4 weeks the tissue was digested and the released larvae were inoculated into mice for determination of the reproductive capacity index (RCI). Larvae of both T. spiralis and T. pseudospiralis survived freezing at −5° and −18 °C for 4 weeks. Received: 10 September 1999 / Accepted: 22 October 1999  相似文献   

6.
The infectivity of Trichinella spiralis, T. nativa, and T. britovi was experimentally compared in pigs. Blood sampling was performed weekly, and muscle juices were obtained at slaughter 10 weeks after inoculation. Muscle larvae were found in all of four pigs inoculated with T. spiralis [mean 190 larvae per gram (lpg)] and in three of four pigs inoculated with T. britovi (mean 7 lpg). No larvae were found in pigs inoculated with T. nativa. For T. spiralis and T. britovi, the neck muscle (m. splenius) appears to be a predilection site in addition to the tongue, the diaphragm, and the jaw. High antibody responses were found in all experimental groups, independent of the antigen used, and even in pigs in which no muscle larvae were recovered. The strong and consistent antibody response found with meat juice indicates the usefulness of this material where a blood sample is not obtainable, e.g. meat samples from wild animals. Immunoblotting (Western blots) on slaughter sera revealed no species specificity when comparing homologous versus heterologous staining. Received: 30 July 1997 / Accepted: 25 September 1997  相似文献   

7.
Oligonucleotide primers were synthesized for the polymerase-chain-reaction amplification of target DNA from two sequences ofTrichinella spiralis. Six strains belonging toT. spiralis, T. nativa, T. britovi, T. pseudospiralis, andT. nelsoni were tested. Amplification products were obtained withT. spiralis, T. britovi, andT. nelsoni DNA from a 53-kDa antigen cDNA sequence and withT. spiralis andT. nelsoni DNA from a 1.6-kb repetitive DNA sequence. Differences in the length of the amplification products obtained from the repetitive sequence would enable a differentiation betweenT. spiralis andT. nelsoni, suggesting that the 1.6 kb repetitive DNA sequence would not be specific forT. spiralis. No amplification was detected forT. nativa orT. pseudospiralis DNA from the two sequences and forT. britovi DNA from the 1.6-kb repetitive DNA sequence.  相似文献   

8.
Mammalian hosts often develop distinct immune response against the diverse parasitic helminths that have evolved for immune evasion. Interleukin-25 (IL-25), an IL-17 cytokine family member, plays a key role in initiating the protective immunity against several parasitic helminths; however, the involvement and underlying mechanisms by which IL-25 mediates immune response against Trichinella spiralis infection have not been investigated. Here we showed that IL-25 functions in promoting protective immunity against T. spiralis infection. Mice treated with IL-25 exhibited a lower worm burden and fewer muscle larvae in the later stage of T. spiralis infection. In contrast, mice treated with neutralizing antibody against IL-25 failed to expel T. spiralis effectively. During T. spiralis infection, intestinal IL-25 expression was rapidly elevated before the onset of IL-4 and IL-9 induction. While antigen-specific Th2 and Th9 immune responses were both developed during T. spiralis infection, an antigen-specific Th9 response appeared to be transiently induced in the early stage of infection. Mice into which antigen-specific T cells deficient in IL-9 were transferred were less effective in worm clearance than those given wild-type T cells. The strength of the antigen-specific Th9 immune response against T. spiralis could be enhanced or attenuated after treatment with IL-25 or neutralizing antibody against IL-25, respectively, correlating positively with the levels of intestinal mastocytosis and the expression of IL-9-regulated genes, including mast cell- and Paneth cell-specific genes. Thus, our study demonstrates that intestinal IL-25 promotes protective immunity against T. spiralis infection by inducing antigen-specific Th9 immune response.  相似文献   

9.
Meat of domestic pigs and wild boars has been the significant source of emerged human trichinellosis in Lithuania, Latvia, and Estonia over the past two decades. However, there is very little known on the occurrence of Trichinella spp. in main wildlife reservoirs and its transmission in domestic and sylvatic cycles in these countries. The present study demonstrated considerably higher endemicity of Trichinella spp. in main sylvatic reservoirs (28.9–42% in foxes (Vulpes vulpes) and raccoon dogs (Nyctereutes procyonoides) in all three countries than previously reported. Molecular identification of Trichinella larvae from more than 500 sylvatic and domestic animals revealed four Trichinella species (Trichinella spiralis, Trichinella britovi, Trichinella nativa, and Trichinella pseudospiralis) sympatric in a relatively small area and several as the first records for the respective countries. The nonencapsulating T. pseudospiralis is found for the first time in the Eastern Europe. Sylvatic T. britovi was found in domestic pigs in Lithuania and Latvia (16 and 57.1%, respectively) and only in these countries, domestic T. spiralis was detected in sylvatic animals in areas where domestic trichinellosis was registered. The study suggests that transmission of Trichinella between domestic and sylvatic cycles in Lithuania and Latvia is favored by improper human behavior, e.g., pig and slaughter waste management.  相似文献   

10.
Epidemiological and experimental studies have indicated that helminth infections can ameliorate autoimmune diseases. The present study investigated the amelioration effect of the Trichinella pseudospiralis infection on experimental autoimmune encephalomyelitis (EAE), a T-cell-mediated autoimmune disease of central nervous system (CNS), and expression kinetics of Th17 and Th1 cytokine which play a crucial role in the pathogenesis of EAE. The results indicated that the infection of helminth T. pseudospiralis obviously ameliorated clinical severity and greatly delayed the onset of EAE induced by myelin oligodendrocyte glycoprotein (MOG) immunization. Infection caused much lesser inflammatory infiltration and demyilination in the CNS of infected EAE mice than uninfected EAE mice. The reduced infiltration was also suggested by the expressions of the inflammation cytokines, IL-17, IL-6, IL-1β, IFN-γ, and TNF-α, which were high in the spinal cords of the uninfected EAE mice, but was nearly normal or low in the infected EAE mice. The increased production of MOG-induced IL-17 and IFN-γ and the expression of IL-6, IL-1β, TGF-β in splenocytes after restimulation with MOG was inhibited in the infected EAE mice. On the other hand, the greatly induced Th2 response was observed in the splenocytes of the infected EAE mice. The present study showed that T. pseudospiralis infection can suppresses EAE by reducing the inflammatory infiltration in CNS, likely associated with the suppression of Th17 and Th1 responses by the infection.  相似文献   

11.
Nematode worms of the genus Trichinella are one of the most widespread zoonotic pathogens. Natural transmission between hosts can only occur through the ingestion of infected meat. To date, two Trichinella species are known to be etiological agents of disease among domestic animals and wildlife in Poland: T. spiralis and T. britovi. In the last decades, since the administration of an oral vaccination against rabies, the red fox population in Poland has increased exponentially. The study area covers the Nowy Targ region: a mountainous area (585–1138 m above the sea) in southern Poland. Of 24 red foxes examined in the study, four were infected with Trichinella isolates: three were identified as T. britovi and one as T. pseudospiralis. The muscle of red foxes infected with T. britovi harboured 2.75, 3.11, 4.4 LPG and with T. pseudospiralis 0.36 LPG. Trichinella larvae were identified at species level by genomic and mitochondrial multiplex PCR, the products of which were sequenced for comparison with other sequences available in GenBank. The sequences obtained from the Polish T. pseudospiralis isolate, deposited in GenBank under the accession numbers JQ809660.1 and JQ809661.1, matched sequences already published in GenBank. Sequence comparison showed a 100% match with the large subunit ribosomal RNA gene of T. pseudospiralis isolate ISS 013, and a 96–95% match with those of T. pseudospiralis isolates ISS 141 and ISS 470. This is the first report of the identification of T. pseudospiralis larvae from red fox in Poland.  相似文献   

12.
In Europe, Serbia ranks among countries with a high prevalence of Trichinella infection in pigs, which continues to be a serious human health problem. While in some Balkan countries, more than one Trichinella species/genotype has been described in both the sylvatic and domestic cycles, these data are lacking for Serbia. To date, only a few Serbian isolates of Trichinella have been genetically specified, and all were classified as T. spiralis. Although transmission of Trichinella from domestic pigs to wildlife could be assumed, neither the infection status nor the species of Trichinella circulating among wildlife in Serbia has been investigated. This study shows the presence of two Trichinella species, T. spiralis and T. britovi, in wild animals originating from five districts in Serbia, where Trichinella infections in domestic pigs and humans have been recorded. Trichinella spiralis was detected in jackals (n = 3), red foxes (n = 2) and a wild cat (n = 1). We also established that wolves (n = 4) and red foxes (n = 2) serve as sylvatic reservoirs for T. britovi. This is the first report on the presence of T. britovi in Serbia.  相似文献   

13.
The following effects of Lactobacillus casei in NIH mice were evaluated: the establishment of Trichinella spiralis adult worms in the intestine (AWI), larvae per gram of muscle tissue (LPG), levels of IgG and IgA, and levels of IL-4 and IFN-γ. One hundred and eight mice were allocated at random into 18 groups of six mice each. Each mouse in treated or non-treated groups was inoculated intraperitoneally once a week during 6 weeks with L. casei or phosphate-buffered solution. Later each mouse was challenged either with 200, 50, or 25 T. spiralis infective larvae. When the infection dose was 200 T. spiralis infective larvae, the reductions in AWI were 78.6% at 4 days after infection (dai) and 76.7% at 10 dai; while the reduction of LPG was 80.9% with respect to control groups. When the infection dose was 50 or 25 T. spiralis infective larvae, the reductions of AWI were 100% both at 4 and 10 dai; while the reduction of LPG at 30 dai was also 100% with respect to control groups. The levels of IgG and IgA anti-T. spiralis and IL-4 were significantly higher (P < 0.01) at 4 and 10 dai in mice from groups treated with L. casei than in animals in control groups; while at 10 dai, the levels of IFN-γ were higher in control mice (P < 0.01) than in L. casei-treated animals. The results suggest that frequent treatment of mice with L. casei induces a total protection against infection with low doses of T. spiralis.  相似文献   

14.
Many epidemiological data support the postulate that infection with helminths might provide some protection against allergic and autoimmune diseases. Hence arises the concept that helminths strongly influence the immune system and enable protective pathways against these hyperimmune-associated disorders. This review discusses how Trichinella spiralis can make the immune system smarter in dealing with hyperimmune-associated disorders. T. spiralis possesses the capacity to direct the immune system towards a mixed Th1/Th2 phenotype with predominance of Th2 response, or it may interfere with dendritic cell maturation, induce the alternatively activated macrophages and elicit the regulatory arm of the immune response via Treg or regulatory B cells.  相似文献   

15.
Herbivorous animals can play a very important role in spreading trichinellosis. In the study presented here, the susceptibility and distribution of Trichinella spiralis infection was examined in 16 goat kids. The goats were inoculated with 10,000 T. spiralis larvae isolated by artificial digestion methods. The animals were necropsied per two animals in weekly intervals, and the larval burdens in different muscle tissue and anti-Trichinella antibodies measured with the indirect enzyme-linked immunosorbent assay (ELISA) serological method using excretory–secretory (E/S) antigen for detecting anti-Trichinella antibodies were assessed during the experiment. T. spiralis larval burden was maximal at 6 weeks postinoculation (480–5,057 larvae/g according to locality), and the larvae were also found in the myocardium (0.77 larvae/g). In this paper, our next step was to compare the specificity and the time of seroconversion by means of ELISA based on E/S antigen prepared from T. spiralis. Antibody response was detected in all 16 goats. The ELISA test carried out showed the first increments in optical density 2 weeks postinfection (p.i.), reached their peak 4 weeks p.i., and remained elevated from that day until the end of the experiment (10 weeks p.i.). These results indicated that specific anti-Trichinella antibodies in goats persist for a relatively long time.  相似文献   

16.
Inflammatory bowel disease (IBD), including ulcerative colitis and Crohn’s disease (CD), are chronic autoimmune diseases with a high recurrence rate. Epidemiological data have shown that the incidence of IBD increases annually because of improved sanitary conditions and reduced parasitic infection rates. In this experiment, experimental colitis was induced in mice by administering 2,4,6-trinitrobenzene sulfonic acid (TNBS) 28?days after they were infected with Trichinella spiralis to confirm that T. spiralis infection could alleviate the severity of TNBS-induced colitis.Thirty-six male BALB/c mice aged 6–8 weeks were randomly divided into four groups: control group (with 50% ethanol, Control), T. spiralis-infected group (TS-Control), TNBS-induced colitis model group (Colitis), and T. spiralis-pre-infected and TNBS-induced colitis group (TS-Colitis). The mice were sacrificed 3, 7, and 14?days after the model was established. Changes in various colitis indicators to investigate the effect of T. spiralis infection on TNBS-induced murine CD model.Results showed that the weight, DAI score, and macroscopic and microscopic colon damage in the TS-Colitis significantly decreased compared with those in the Colitis. ELISA revealed that the IFN-γ expression decreased and the IL-4 expression increased in the TS-Colitis compared with those in the Colitis. Western Blotting results revealed that the NF-κB expression increased in the Colitis and higher than those in the TS-Colitis. And Flow cytometry results revealed that the percentage of CD4+CD25+Foxp3+ Treg cells significantly increased in the TS-Colitis.T. spiralis-infected mice induced Th2 immune responses and balanced Th1 immune responses stimulated by TNBS to ameliorate intestinal inflammation.  相似文献   

17.
A cDNA library for Trichinella pseudospiralis was constructed to study the expression of specific antigens. Four positive clones were identified using antibodies against the excretory/secretory (ES) products of the nematode as probe. Sequence analysis showed that they contained identical cDNA inserts of 606 bp, including a 5′ non-translated region of 96 bp, a core translated segment of 408 bp and a poly(A)+ 3′ terminus. It encoded a novel 136-amino-acid polypeptide. Southern blot analysis indicated that the cDNA did not cross-hybridize to the genomic digests of T. spiralis, mouse, or rat. A single copy only of its complementary sequence was found in the genome of T. pseudospiralis. Using the lambda ZAP expression system, the cDNA was induced to express a 23-kDa β-galactosidase-fusion protein which did not cross-react with polyclonal and monoclonal antibodies against T. spiralis, heat shock proteins, or four heterologous species of nematodes. The antiserum against the fusion protein recognized a 15-kDa band from the ES products of T. pseudospiralis in immunoblotting. Immunocytolocalization demonstrated that the anti-fusion protein serum only recognized an epitope in the stichosome of T. pseudospiralis and not in T. spiralis. The protein can therefore serve as a specific antigen for the differential diagnosis of trichinellosis. Received: 22 December 1998 / Accepted: 17 February 1999  相似文献   

18.
Antigenic differences betweenTrichinella spiralis andT. pseudospiralis were established using two monoclonal antibodies (mAbs) that show different specificities to muscle larvae of the two variants. Enzymelinked immunosorbent assay (ELISA) revealed that mAb 3G6 reacts positively againstT. spiralis, T. nelsoni, T. nativa andT. pseudospiralis, whereas mAb 3E10 does not react withT. pseudospiralis under the same experimental conditions. These antigenic differences were confirmed after preabsorption of the antibodies with serial dilutions of extracts ofT. spiralis orT. pseudospiralis muscle larvae. The indirect immunofluorescence technique showed that the antigen corresponding to mAb 3G6 is located in the stichosomes and the cuticle surface of bothT. spiralis andT. pseudospiralis. In contrast, mAb 3E10 positively stained cryostat sections ofT. spiralis, forming a dense reaction product on the surface of the whole larvae and the surrounding capsule. This antibody can be quite useful as a specific probe for distinguishingT. spiralis fromT. pseudospiralis in taxonomic studies. Using an avidin-biotin system, we could prove that mAb 3G6 recognizes an excretory/secretory-type antigen.  相似文献   

19.
Trichinellosis is a widespread zoonoses for which no effective drug treatment is available at this time. Though anthelmintics such as mebendazole and albendazole are commonly used to treat human trichinellosis, none of these drugs are fully effective against the encysted or new-born larvae of Trichinella spiralis. In recent years, there has been a growing interest in developing newer anthelminthics from medicinal plants, particularly the ones used in traditional medicines in many parts of the world, due to the increasing spread of anthelminthic resistance and/or decreasing activity against encapsulated larval stages of parasites. The aim of the present study was to investigate the efficacy of leaf extract of Lasia spinosa (Araceae) against different life cycle stages of T. spiralis, i.e. adult (days 3 and 4 post-infection), migrating larvae (days 8, 9 and 10 post-infection) and encysted muscle larvae (days 31–37 post-infection). The study showed that L. spinosa leaf extract is effective against all the three life cycle stages of parasite. Against the adult stage, an oral administration of plant extract at 800 mg/kg dose revealed a 75.30% reduction in the number of adult worms, as compared to untreated controls at day 10 post-infection. Whereas against migrating larvae, the same dose of plant extract given for 3 days, reduced the number of larvae recovered from musculature of treated animals by 72.23%. However, in comparison of preceding two stages, the extract showed comparatively less efficacy against the encysted larvae of parasite. In this case, the 800 mg/kg dose of extract given for 7 days (after 30 day of post-infection) revealed only 64.84% reduction in the number of encysted larvae, as was evident from larval count on day 49 post-infection. Therefore, the results of this study indicate that leaf extract of L. spinosa possesses significant anthelminthic efficacy against the adult stages and migrating larvae of T. spiralis. On the other hand, the encysted muscle larvae of parasite are comparatively less sensitive to L. spinosa leaf extract treatment.  相似文献   

20.
The parasitic nematode Trichinella spiralis can cause trichinellosis, which leads to pathological processes in the intestine and muscle. The intestinal invasion determines the development, subsequent course, and consequences of the disease. Gastrointestinal nematode infection, including with T. spiralis, is accompanied by a rapid and reversible expansion of mucosal mast cell and goblet cell in the intestinal epithelium, which play important roles in the host immune response to parasite and worm expulsion from the intestine. Taurine and its derivatives have anti-infection and anti-inflammatory properties. We investigated whether taurine supplementation in mice could influence the development and pathological processes of infection with T. spiralis. Supplementing 1 % taurine in drinking water in mice infected with T. spiralis could alleviate the burden of intestinal adult worms on days 7 and 10 postinfection (all p?<?0.01) and the formation of infective muscle larvae in striated muscle during T. spiralis infection (p?<?0.01). As compared with T. spiralis infection alone, taurine treatment increased the number of goblet cells on days 7, 10, and 15 (p?<?0.01 and p?<?0.05) and alleviated intestinal mucosal mast cell hyperplasia on days 10 and 15 (all p?<?0.01). So taurine supplementation in drinking water increased infection-induced intestinal goblet cell hyperplasia and ameliorated mucosal mastocytosis. Thus, taurine can ameliorate the pathological processes of trichinellosis and may be of great value for the treatment and prevention of infection with T. spiralis and other gastrointestinal nematodes.  相似文献   

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