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1.
Parasitol Res ; 121(1): 403-411, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34993637

RESUMO

Cystoisospora belli causes chronic diarrhoea, acalculous cholecystitis, cholangiopathy and disseminated cystoisosporosis in patients with AIDS. Clinical manifestations and histological stages during C. belli infection in a patient with AIDS and liver disease were described. It was possible to identify sporozoite-like structures in the villus epithelium of the duodenum, close to the vascularization that underlies the basal membrane and unizoite tissue cysts near to the vascularization in the lamina propria. Unizoite tissue cysts were found inside of sinusoids in the liver communicating with the central vein and with a bile canaliculus and portal spaces. Based on these findings a hypothesis on C. belli life cycle could consider that the route of migration of unizoite tissue cysts up the liver is via the portal blood. The unizoite tissue cysts located in hepatic portal vein could migrated via sinusoid to central vein and general circulation through the venous system. The unizoite tissue cysts could also return via bile canaliculus to bile duct to portal triad. This hypothesis allows to understand the presence of unizoite stages in blood, the pathway by which the bile ducts become infected and unizoites in the liver being able to behave like hypnozoites that favour relapses and treatment failures.


Assuntos
Coccidiose , Isosporíase , Hepatopatias , Animais , Humanos , Mucosa Intestinal , Estágios do Ciclo de Vida , Fígado
3.
Vet Parasitol ; 301: 109641, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34979475

RESUMO

Ovine neosporosis, caused by the Apicomplexan parasite Neospora caninum, leads to reproductive failure worldwide. Nowadays, there is a trend to develop diagnostic techniques using non-invasive samples, such as milk, in order to reduce animal stress, sample collection effort, and costs. The objective of this study was to develop and validate a highly sensitive and specific serological technique, based on a time resolved-fluorescence immunoassay using a N. caninum GRA7 antigen (GRA7-TRFIA), for the detection of anti-N. caninum immunoglobulins G on sheep' full-cream milk samples. An analytical validation was performed, including intra- and inter-assay precision, analytical sensitivity and accuracy. The diagnostic performance of the assay was evaluated by studying the positive-negative discrimination by Mann Whitney U tests. In additon optimal cut-offs, diagnostic sensitivity and specificity, and areas under the curve were calculated by three Receiver Operating Curve (ROC) analyses, using GRA7-TRFIA and a N. caninum tachyzoite soluble extract-based ELISA (NcSALUVET-ELISA) in blood sera, and the coinciding results of both techniques, as reference techniques. Moreover, Spearman's correlation of GRA7-TRFIA in milk with the techniques in sera and agreement (kappa values) were also estimated. GRA7-TRFIA for milk samples showed an adequate precision, with high analytical sensitivity and accuracy. Regarding ROC analyses, at the optimal cut-offs, the diagnostic sensitivity and specificity were more than 90 % in all cases. In addition, GRA7-TRFIA values in milk were more positively correlated to GRA7-TRFIA values in blood sera than in the case of values obtained with NcSALUVET-ELISA. GRA7-TRFIA in milk showed an almost perfect agreement with GRA7-TRFIA in blood sera (kappa = 0.98) and with the coinciding results of GRA7-TRFIA and NcSALUVET in blood sera (kappa = 1.00), while it has a substantial agreement with NcSALUVET-ELISA (kappa = 0.69). In the light of these results, GRA7-TRFIA in full-cream milk samples is a highly sensitive technique that could be used for screening anti-N. caninum antibodies in sheep flocks.


Assuntos
Doenças dos Bovinos , Coccidiose , Neospora , Doenças dos Ovinos , Animais , Anticorpos Antiprotozoários , Bovinos , Coccidiose/diagnóstico , Coccidiose/veterinária , Ensaio de Imunoadsorção Enzimática/veterinária , Leite , Sensibilidade e Especificidade , Ovinos , Doenças dos Ovinos/diagnóstico
4.
Rev Bras Parasitol Vet ; 31(1): e017421, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35019027

RESUMO

The present study aimed to perform an epidemiological and morphological identification of Eimeria infection in sheep in Brazil. Fecal samples from sheep were collected from 20 farms in northern Paraná, Brazil. An epidemiological questionnaire was used to evaluate the risk factors. Fecal samples containing oocysts per gram of feces (OoPG) ≥1000 were subjected to the modified Willis-Mollay method to perform oocyst identification. Sporulated oocysts were observed microscopically for morphological identification. A total of 807 fecal samples were collected. Based on the morphological characteristics of the sporulated oocysts, 10 species of Eimeria were identified, with main species observed: Eimeira ovinoidalis (98.1%), Eimeria crandallis (87.6%), Eimeria parva (79.1%), and Eimeria bakuensis (60.8%). Only 2.6% (7/268) of the sheep were infected with a single species, 4.8% (13/268) contained two different species, and 92.5% (248/268) were infected with three or more species. The analysis of risk factors showed that an intensive rearing, no rotation of pasture, dirt, and slatted floors, and age up to 12 months were associated with infection. This study showed a high prevalence of Eimeria natural infection in sheep from northern Paraná, Brazil. Furthermore, based on the risk factors, good management and hygiene practices must be employed to avoid infection.


Assuntos
Coccidiose , Eimeria , Doenças dos Ovinos , Animais , Brasil/epidemiologia , Coccidiose/epidemiologia , Coccidiose/veterinária , Fezes , Prevalência , Fatores de Risco , Ovinos , Doenças dos Ovinos/epidemiologia
5.
Parasitol Int ; 86: 102478, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34626806

RESUMO

Madura cattle, which are native to Indonesia and mainly kept on Madura Island, East Java, are expected to contribute to improving the regional meat self-sufficiency. Eimeria spp. are the most pathogenic protozoans among gastrointestinal parasites in livestock but no molecular surveys of Eimeria spp. in Madura cattle have been conducted to date. In this study, a total of 183 fecal samples were collected from Madura cattle and 60 (32.8%) were positive for parasites of protozoans and nematodes by the sugar floatation method. Among the samples with parasites, Eimeria spp. oocysts were detected in 50 samples (27.3%) with an average OPG value of 1686.1. Eimeria spp. were successfully identified to the species level in 26 samples with Eimeria bovis being the most prevalent, followed by E. zuernii and E. aubrunensis. A total of 21 samples showed mixed infection of more than two species of Eimeria. E. bovis and E. zuernii have been recognized as having high virulency and, thus, these parasites are potential sources of severe coccidiosis and the cause of infections in other cattle. Although additional studies are warranted, these results can be helpful for improving the management and productivity of Madura cattle.


Assuntos
Doenças dos Bovinos/epidemiologia , Coccidiose/veterinária , Eimeria/isolamento & purificação , Fezes/parasitologia , Animais , Bovinos , Doenças dos Bovinos/parasitologia , Coccidiose/epidemiologia , Eimeria/classificação , Eimeria/genética , Indonésia/epidemiologia , Oocistos/isolamento & purificação , Contagem de Ovos de Parasitas/veterinária
6.
Vet Parasitol ; 301: 109642, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34971828

RESUMO

Eimeria necatrix, an apicomplexan protozoa of the genus Eimeria, causes intestinal coccidiosis that can reduce growth performance of poultry and result in high mortality in older chickens. In this report, the whole sporozoite proteins of E.necatrix were studied by two-dimensional electrophoresis (2-DE) and Western blotting using hyper-immune chicken serum containing E.necatrix-specific antibodies. Approximately 680 protein spots for E.necatrix sporozoite were detected by 2-DE with silver staining, where 98 spots were cross-reacted with the E. necatrix-specific immune sera. Out of the 56 spots that were selected for MALDI-TOF-MS/MS analysis, 50 unique proteins were identified using the MASCOT software, 8 proteins were identified as known E.necatrix proteins and the rest were all putative proteins. These proteins have a wide range of known or predicted structures, cellular locations and functions, including proteins in category nuclear location & function, multifunctional- or multifunctional motifs-containing proteins, cellular transport and structure-related proteins, proteins of enzymatic activities, motor proteins-related, cell surface and organelle-related proteins. These new findings will enhance our understandings of parasite immunogenicity and immune evasion mechanisms of E. necatrix and facilitate the discovery phase of highly effective vaccine candidates.


Assuntos
Coccidiose , Eimeria , Doenças das Aves Domésticas , Animais , Galinhas , Coccidiose/veterinária , Esporozoítos , Espectrometria de Massas em Tandem/veterinária
7.
Microb Pathog ; 162: 105357, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34896546

RESUMO

Rabbit coccidiosis is a common parasitic disease leading to economic losses in the rabbit industry. The intestinal flora plays a key role in pathogenesis of coccidiosis, and fecal metabolome mediates host-microbiome interactions as a functional readout of the gut microbiome. In this study, the E. intestinalis-infected and E. magna-infected rabbit models were established to investigate metabolic alterations and metabolic pathways based on LC-MS/MS technique for the first time. Multivariate OPLS-DA analysis was performed to explore differential metabolites. In total, 288 metabolites were detected from infected and uninfected rabbits. The level of 33 metabolites increased and 4 decreased in rabbits infected with E. intestinalis. Eight pathways were significantly perturbed during E. intestinalis infection including biosynthesis of unsaturated fatty acids, fatty acid biosynthesis, etc. After rabbits infected with E. magna, 13 metabolites were altered and 7 metabolic pathways were dysregulated. These metabolites and metabolic pathways were mainly involved in tuberculosis, parathyroid hormone synthesis, etc. Besides, 25 metabolites differed in abundance between E. intestinalis infection group and E. magna infection group, the major perturbed metabolic pathways were lipid metabolism and endocrine system, respectively. In general, it is confirmed that E. intestinalis and E. magna infection destroyed the intestinal flora, which caused corresponding changes in metabolites, and provide novel insights into the molecular mechanisms of rabbit-parasite interactions.


Assuntos
Coccidiose , Eimeria , Animais , Cromatografia Líquida , Coccidiose/veterinária , Metabolômica , Coelhos , Espectrometria de Massas em Tandem
8.
Trop Anim Health Prod ; 54(1): 28, 2021 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-34961903

RESUMO

This study consists of the evaluation of the anticoccidial effect of Artemisia herba-alba Asso during experimental coccidial infection. Four groups of 30 broiler chickens were formed: the negative control (G1), the positive control (G2), the infected Monensin-treated group (G3), and the infected Artemisia-treated group (G4). Each infected bird received orally 105 sporulated oocysts of Eimeria tenella. No mortality was recorded in both G1 and G4. Haematocrit levels showed great variations from the 7th day post-infection, especially in G2 (20.87% ± 5.77). By day 10 P-I, haematocrit recovery was rapid particularly in G4 (28.07% ± 1.50). Haemoglobin concentration also decreased significantly (p < 0.05) in all infected groups by the 7th day P-I. The reduction was very marked, but not statistically significant, in G2 (6.47 g/dL ± 1.67) against (10.53 g/dL ± 0.25) in G1. It was less marked in G4 (8.05 g/dL ± 1.56). Results show the protective effect of A. herba-alba Asso by improving the lesion score and the haematological parameters affected during coccidian infection.


Assuntos
Artemisia , Coccidiose , Coccidiostáticos , Doenças das Aves Domésticas , Animais , Galinhas , Coccidiose/tratamento farmacológico , Coccidiose/veterinária , Coccidiostáticos/farmacologia , Coccidiostáticos/uso terapêutico , Oocistos , Doenças das Aves Domésticas/tratamento farmacológico
9.
Korean J Parasitol ; 59(5): 439-445, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34724762

RESUMO

Coccidiosis in chickens is an intestinal parasitic disease caused by protozoan parasites named Eimeria spp. In some Eimeria infections, intestinal lymphocytes are known to highly express chicken NK-lysin (cNK-lysin), an antimicrobial peptide with anticoccidial activity. Therefore, this study aims to investigate the expression of cNK-lysin in E. necatrix-infected chickens and its role in E. necatrix infection. The expression of cNK-lysin transcript was significantly increased in E. necatrix sporozoites-treated lymphocytes. In E. necatrix infection, cNK-lysin transcript was induced in intestinal lymphocytes but not in the spleen. The recombinant cNK-lysin exhibited anticoccidial activity against E. necatrix sporozoites as well as immunomodulatory activity on macrophages by inducing proinflammatory cytokines. These results indicated that E. necatrix infection induces high local expression of cNK-lysin and the secreted cNK-lysin helps protect coccidiosis.


Assuntos
Coccidiose , Eimeria , Doenças das Aves Domésticas , Animais , Galinhas , Coccidiose/veterinária , Proteolipídeos
10.
Trop Anim Health Prod ; 53(6): 528, 2021 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-34725745

RESUMO

The aim of this study was to estimate the molecular prevalence of Toxoplasma gondii, Neospora caninum and the co-infection by both Apicomplexan parasites in uterus tissues of cows. PCR was used to detect T. gondii and N. caninum DNA in uterus from 140 uteri of slaughtered cows in the regional slaughterhouse of Béja (Northwest Tunisia). Positive PCR products were sequenced and used for the phylogenetic analysis. The overall molecular prevalence of T. gondii and N. caninum in cows' uterus was 5 and 15.57%, respectively. Co-infection prevalence by the two parasites was estimated to be 2.85%. Risk factors including the age categories significantly affected the molecular prevalence of T. gondii and N. caninum in cows' uterus. The highest molecular prevalence of T. gondii (11.5 ± 3.1) and N. caninum (21.1 ± 11.1; p = 0.038) was observed in cows aged of more than 8 years. There were no differences depicted according to cow's breeds and localities. Comparison of the partial sequences of the ITS1 gene revealed 100% similarity among our N. caninum sequence (MW136256) and those deposited in GenBank. The T. gondii sequence described in this study (MW260335) was 99.4-100% homologous to T. gondii sequences published in the GenBank.To the best of our knowledge, this is the first molecular evidence of N. caninum and T. gondii co-infection in naturally infected cows in North Africa. This information is pertinent in designing control programmes that would reduce economic losses in the livestock industry.


Assuntos
Coccidiose , Coinfecção , Neospora , Toxoplasma , Toxoplasmose Animal , Animais , Anticorpos Antiprotozoários , Bovinos , Coccidiose/epidemiologia , Coccidiose/veterinária , Coinfecção/epidemiologia , Coinfecção/veterinária , Feminino , Genitália , Neospora/genética , Filogenia , Estudos Soroepidemiológicos , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Tunísia/epidemiologia
11.
Trop Anim Health Prod ; 53(5): 497, 2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34609608

RESUMO

To explore the potential alternative of anti-coccidials, we investigated the therapeutic efficacy of dietary Piper sarmentosum extract (PSE) on induced coccidia infection in chickens. A total of 96-day-old chickens were randomly distributed to 1 of 3 treatment groups, including (1) control negative untreated uninfected (CN), (2) control positive untreated infected (CP), and (3) Piper sarmentosum (P. sarmentosum) extract-treated infected group (PSE). Our results demonstrated that E. tenella challenged untreated group showed a reduction (P < 0.05) in post-infection (PI) body weight compared to control negative group. However, supplementation of P. sarmentosum extract had no significant effects on body weight and cecal lesions compared with control positive group. Infected chickens fed PSE diet decreased (P < 0.05) the bloody diarrhea scores and oocyst shedding (during the day 5 to 8 post-infection) than that of CP chickens. E. tenella-challenged chickens upregulated (P < 0.05) the mRNA expression of IL-8 and Bcl-2 compared to PSE chickens, while IFN-γ compared to CN chickens. On the other hand, treatment of P. sarmentosum extract tended to increase (P < 0.05) the transcription patterns of IL-4, IL-10, CLDN 1, SOD 1, and Bax with the comparison of control positive group; however, there were no significant effects on IL-8, ZO 1, and CAT expression between the PSE and CP groups. Collectively, these findings elaborated that dietary P. sarmentosum extract exhibit potential anti-coccidial effects in controlling the coccidia infection in chickens.


Assuntos
Coccidiose , Eimeria tenella , Piper , Doenças das Aves Domésticas , Animais , Galinhas , Coccidiose/tratamento farmacológico , Coccidiose/veterinária , Suplementos Nutricionais , Doenças das Aves Domésticas/tratamento farmacológico
12.
PLoS One ; 16(10): e0258157, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34597342

RESUMO

Eimeria parasites cause enteric disease in livestock and the closely related Cyclospora cayetanensis causes human disease. Oocysts of these coccidian parasites undergo maturation (sporulation) before becoming infectious. Here, we assessed transcription in maturing oocysts of Eimeria acervulina, a widespread chicken parasite, predicted gene functions, and determined which of these genes also occur in C. cayetanensis. RNA-Sequencing yielded ~2 billion paired-end reads, 92% of which mapped to the E. acervulina genome. The ~6,900 annotated genes underwent temporally-coordinated patterns of gene expression. Fifty-three genes each contributed >1,000 transcripts per million (TPM) throughout the study interval, including cation-transporting ATPases, an oocyst wall protein, a palmitoyltransferase, membrane proteins, and hypothetical proteins. These genes were enriched for 285 gene ontology (GO) terms and 13 genes were ascribed to 17 KEGG pathways, defining housekeeping processes and functions important throughout sporulation. Expression differed in mature and immature oocysts for 40% (2,928) of all genes; of these, nearly two-thirds (1,843) increased their expression over time. Eight genes expressed most in immature oocysts, encoding proteins promoting oocyst maturation and development, were assigned to 37 GO terms and 5 KEGG pathways. Fifty-six genes underwent significant upregulation in mature oocysts, each contributing at least 1,000 TPM. Of these, 40 were annotated by 215 GO assignments and 9 were associated with 18 KEGG pathways, encoding products involved in respiration, carbon fixation, energy utilization, invasion, motility, and stress and detoxification responses. Sporulation orchestrates coordinated changes in the expression of many genes, most especially those governing metabolic activity. Establishing the long-term fate of these transcripts in sporulated oocysts and in senescent and deceased oocysts will further elucidate the biology of coccidian development, and may provide tools to assay infectiousness of parasite cohorts. Moreover, because many of these genes have homologues in C. cayetanensis, they may prove useful as biomarkers for risk.


Assuntos
Coccídios/genética , Coccidiose/genética , Eimeria/genética , Regulação da Expressão Gênica/genética , Animais , Biomarcadores/metabolismo , Galinhas/genética , Galinhas/parasitologia , Coccídios/patogenicidade , Coccidiose/parasitologia , Cyclospora/genética , Cyclospora/parasitologia , Eimeria/patogenicidade , Humanos , Gado/parasitologia , Modelos Biológicos
13.
Parasitol Res ; 120(11): 3875-3882, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34599357

RESUMO

Neospora caninum has been implicated as a sporadic cause of abortion and perinatal deaths in sheep flocks globally. However, its significance as a reproductive pathogen for sheep in Australia remains unknown. The aims of this study were to (i) determine the seroprevalence of N. caninum in Australian breeding ewes and (ii) examine if natural exposure to N. caninum is associated with poor reproductive performance of primiparous ewes in southern Australia. Thirty flocks of primiparous ewes (aged 1-2 years old at lambing) from 28 farms in three states (Western Australia, South Australia and Victoria) were monitored between mating and lamb marking. Blood samples were also collected from multiparous mature ewes (aged 3 years or older) at each farm. Seroprevalence for anti-N. caninum IgG using indirect ELISA was determined for a subset of primiparous ewes that were predominantly determined to be pregnant and subsequently failed to rear a lamb (n = 1279) and randomly selected mature multiparous ewes with unknown reproductive status (n = 558). Neopsora caninum apparent seroprevalence was 0.16% (95% confidence interval 0.03%, 0.5%) in primiparous ewes, with seropositivity identified in two ewes from farms located in South Australia and Victoria. There was no evidence of seropositivity in mature ewes with apparent seroprevalence 0% (0%, 0.45%). These findings suggest that N. caninum infection was not widespread in primiparous ewes or mature multiparous ewes on these farms, and exposure to N. caninum infection was unlikely to explain abortion and perinatal mortalities observed for primiparous ewes.


Assuntos
Coccidiose , Neospora , Animais , Anticorpos Antiprotozoários , Austrália/epidemiologia , Coccidiose/epidemiologia , Coccidiose/veterinária , Estudos Transversais , Feminino , Gravidez , Estudos Soroepidemiológicos , Ovinos , Austrália do Sul
14.
Trop Anim Health Prod ; 53(5): 493, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34599403

RESUMO

Proper health management is essential for productivity in duck farming. However, there is limited information on the effect of management conditions on rates of metabolic problems and parasitic infections in anatids. We evaluated the rates of metabolic syndromes and gastrointestinal parasite involvement in Muscovy ducks up to 12 weeks of age, under 3 management conditions: backyard, organized, and organized with probiotics. Individuals under organized management developed 2 metabolic problems: ascites, which was rare (3.5%), fatal, and affected both males and females, and angel wing syndrome, which was more frequent (10.6%), has low impact on general health, and only affected males. The treatments do not have a significant effect on the development of ascites, but only individuals in controlled conditions presented this syndrome, and due to its low prevalence, further studies with a larger sample size are required. The risk of angel wing syndrome increased significantly with probiotic supplementation. Regarding to parasitic infection, the improvement of sanitary management and the use of probiotics supplementation reduced the occurrence of coccidiosis. Similarly organized management with probiotic supplementation showed a protective effect on helminthiasis by reducing the frequency of Heterakis gallinarum and greatly reducing the helminth egg load. Coccidiosis and helminthiasis infections were not significantly correlated with the final weight of the ducks. Therefore, organized management and the use of probiotics seems to reduce the impact of parasitic infection, although it increases the risk of developing metabolic syndrome.


Assuntos
Coccidiose , Doenças Transmissíveis , Síndrome Metabólica , Doenças Parasitárias , Animais , Coccidiose/veterinária , Doenças Transmissíveis/veterinária , Patos , Feminino , Masculino , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/veterinária
15.
Front Cell Infect Microbiol ; 11: 751481, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34660347

RESUMO

As a common parasitic disease in animals, coccidiosis substantially affects the health of the host, even in the absence of clinical symptoms and intestinal tract colonization. Gut microbiota is an important part of organisms and is closely related to the parasite and host. Parasitic infections often have adverse effects on the host, and their pathogenic effects are related to the parasite species, parasitic site and host-parasite interactions. Coccidia-microbiota-host interactions represent a complex network in which changes in one link may affect the other two factors. Furthermore, coccidia-microbiota interactions are not well understood and require further research. Here, we discuss the mechanisms by which coccidia interact directly or indirectly with the gut microbiota and the effects on the host. Understanding the mechanisms underlying coccidia-microbiota-host interactions is important to identify new probiotic strategies for the prevention and control of coccidiosis.


Assuntos
Coccídios , Coccidiose , Microbioma Gastrointestinal , Microbiota , Animais , Intestinos
16.
Folia Parasitol (Praha) ; 682021 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-34642290

RESUMO

Although intranuclear coccidiosis was first identified in chelonians less than 30 years ago, it is now considered an important emerging disease. Symptoms include anorexia, weakness and weight loss, potentially leading to death of the infected animal. The use of molecular tools has led to improved diagnosis and has also led to an increase in known host species. Here we report a putative intranuclear coccidium in Mauremys leprosa (Schweigger), from Morocco, based on 18S rDNA sequence analysis. This is, to the best of our knowledge, the first report of this parasite from a freshwater terrapin species.


Assuntos
Coccídios/isolamento & purificação , Coccidiose/veterinária , Tartarugas/parasitologia , Animais , Coccídios/genética , Coccidiose/parasitologia , DNA Ribossômico/genética , Água Doce/parasitologia , Marrocos
17.
Front Cell Infect Microbiol ; 11: 675219, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34650932

RESUMO

Listeria monocytogenes (LM) has been proposed as vaccine vector in various cancers and infectious diseases since LM induces a strong immune response. In this study, we developed a novel and safe LM-based vaccine vector platform, by engineering a triple attenuated mutant (Lm3Dx) (ΔactA, ΔinlA, ΔinlB) of the wild-type LM strain JF5203 (CC 1, phylogenetic lineage I). We demonstrated the strong attenuation of Lm3Dx while maintaining its capacity to selectively infect antigen-presenting cells (APCs) in vitro. Furthermore, as proof of concept, we introduced the immunodominant Neospora caninum (Nc) surface antigen NcSAG1 into Lm3Dx. The NcSAG1 protein was expressed by Lm3Dx_SAG1 during cellular infection. To demonstrate safety of Lm3Dx_SAG1 in vivo, we vaccinated BALB/C mice by intramuscular injection. Following vaccination, mice did not suffer any adverse effects and only sporadically shed bacteria at very low levels in the feces (<100 CFU/g). Additionally, bacterial load in internal organs was very low to absent at day 1.5 and 4 following the 1st vaccination and at 2 and 4 weeks after the second boost, independently of the physiological status of the mice. Additionally, vaccination of mice prior and during pregnancy did not interfere with pregnancy outcome. However, Lm3Dx_SAG1 was shed into the milk when inoculated during lactation, although it did not cause any clinical adverse effects in either dams or pups. Also, we have indications that the vector persists more days in the injected muscle of lactating mice. Therefore, impact of physiological status on vector dynamics in the host and mechanisms of milk shedding requires further investigation. In conclusion, we provide strong evidence that Lm3Dx is a safe vaccine vector in non-lactating animals. Additionally, we provide first indications that mice vaccinated with Lm3Dx_SAG1 develop a strong and Th1-biased immune response against the Lm3Dx-expressed neospora antigen. These results encourage to further investigate the efficiency of Lm3Dx_SAG1 to prevent and treat clinical neosporosis.


Assuntos
Coccidiose , Listeria monocytogenes , Neospora , Vacinas Protozoárias , Animais , Antígenos de Protozoários , Antígenos de Superfície , Feminino , Lactação , Listeria monocytogenes/genética , Camundongos , Camundongos Endogâmicos BALB C , Filogenia , Gravidez , Vacinas Protozoárias/genética
18.
Parasite ; 28: 70, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34665126

RESUMO

We examined 674 fresh fecal samples from forest musk deer (Moschus berezovskii Flerov) in Sichuan and Shaanxi Provinces, China, for coccidian oocysts and 65% were infected with Eimeria spp. Previously, only four Eimeria species were known from Moschus spp. Here we describe six new Eimeria species. Eimeria aquae n. sp., in 38% deer, has ovoidal oocysts, 32.0 × 23.0 µm, micropyle (M) and scattered polar granules (PGs) of various sizes are present, sometimes oocyst residuum (OR) is present; ovoidal sporocysts, 14.1 × 7.5 µm, with Stieda body (SB) and sporocyst residuum (SR). Eimeria dolichocystis n. sp., in 11% deer; cylindroidal oocysts, 36.6 × 18.9, with a M, 1 PG and OR; ovoidal sporocysts, 13.9 × 7.7, with SB and SR. Eimeria fengxianensis n. sp., in 7% deer; ovoidal oocysts, 36.3 × 25.2, a M and PGs present but OR absent; ovoidal sporocysts, 13.9 × 7.3, with SB and SR. Eimeria helini n. sp. in 24% deer; subspheroidal oocysts, 27.0 × 24.1, OR and PGs often present, but M absent; ovoidal sporocysts, 13.5 × 7.7, with SB and SR. Eimeria kaii n. sp. in 26% deer; ovoidal oocysts, 33.2 × 20.7, M and PGs present, but OR absent; ovoidal sporocysts, 14.4 × 7.5, with SB and SR. Eimeria oocylindrica n. sp., in 17% deer; cylindroidal oocysts, 36.0 × 21.4, M and 1-2 PGs present but OR absent; ovoidal sporocysts, 13.8 × 7.7, with SB and SR. Eimeria dujiangyanensis n. nom. is proposed to replace E. moschus Sha, Zhang, Cai, Wang & Liu, 1994, a junior homonym of E. moschus Matschoulsky, 1947.


Assuntos
Coccidiose , Cervos , Eimeria , Parasitos , Animais , China/epidemiologia , Coccidiose/epidemiologia , Coccidiose/veterinária , Ácidos Graxos Monoinsaturados , Fezes , Florestas
19.
Rev Bras Parasitol Vet ; 30(3): e010621, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34495126

RESUMO

Aimed with this study to evaluate vertical transmission of Neospora caninum in naturally infected sheep and to monitor the kinetics of antibodies against this protozoon in their lambs. Therefore, 48 pregnant ewes, from five herds, were divided into two groups: G1 - positive for anti-N. caninum antibodies, with 19 animals; and G2 - seronegative, with 29 animals. Blood samples were taken from the ewes and their lambs, immediately after birth, before ingesting colostrum, and 2, 7, 14, 21, 28, 35, 42, 49 and 56 days after birth. Analysis on serum antibodies was performed using the indirect immunofluorescent antibody test. Among the 19 seropositive mothers, six (31.6%) gave birth to lambs seropositive before ingesting colostrum and it was found that these lambs remained positive until the end of the study (56 days). Only one of the lambs, from a ewe that presented an antibody titer of 200, seroconverted after ingestion of colostrum. All the lambs that had been born from negative mothers remained negative throughout the experimental period. It was concluded that transplacental transmission was an important form of diffusion of N. caninum in the herds studied and that seropositive lambs maintained circulating antibodies during the period analyzed.


Assuntos
Coccidiose , Neospora , Doenças dos Ovinos , Animais , Anticorpos Antiprotozoários , Brasil , Coccidiose/veterinária , Feminino , Transmissão Vertical de Doenças Infecciosas/veterinária , Cinética , Gravidez , Ovinos
20.
Mol Immunol ; 139: 140-152, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34509754

RESUMO

Neospora caninum is an intracellular parasite which can cause neosporosis and significant economic losses in both dairy and beef industries worldwide. A better understanding of the immune response by host cells against N. caninum could help to design better strategies for the prevention and treatment of neosporosis. Although previous studies have shown TLR2/TLR3 were involved in controlling N. caninum infection in mice, the precise mechanisms of the AKT and MAPK pathways controlled by TLR2/TLR3 to regulate N. caninum-induced IL-12p40 production and the role of TLR2/TLR3 in anti-N. caninum infection in bovine macrophages remain unclear. In the present study, TLR2-/- mice displayed more parasite burden and lower level of IL-12p40 production compared to TLR3-/- mice. N. caninum could activate AKT and ERK signaling pathways in WT mouse macrophages, which were inhibited in TLR2-/- and TLR3-/- mouse macrophages. In N. caninum-infected WT mouse macrophages, AKT inhibitor or AKT siRNA could decrease the phosphorylation of ERK. AKT or ERK inhibitors reduced the production of IL-12p40 and increased the number of parasites. The productions of ROS, NO, and GBP2 were significantly reduced in TLR2-/- and TLR3-/- mouse macrophages. Supplementation of rIL-12p40 inhibited N. caninum proliferation and rescued the productions of IFN-γ, NO, and GBP2 in WT, TLR2-/-, and TLR3-/- mouse macrophages. In bovine macrophages, the expressions of TLR2, TLR3, and IL-12p40 mRNA were significantly enhanced by N. caninum, and N. caninum proliferation was inhibited by TLR2/TLR3 agonists. Taken together, the proliferation of N. caninum in mouse macrophages was controlled by the TLR2/TLR3-AKT-ERK signal pathway via increased IL-12p40 production, which in turn lead to the productions of NO, GBP2, and IFN-γ during N. caninum infection. And in bovine macrophages, TLR2 and TLR3 contributed to inhibiting N. caninum proliferation via increased IL-12p40 production.


Assuntos
Coccidiose/imunologia , Subunidade p40 da Interleucina-12/imunologia , Macrófagos/imunologia , Transdução de Sinais/imunologia , Animais , Bovinos , Sistema de Sinalização das MAP Quinases/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Neospora/imunologia , Proteína Oncogênica v-akt/imunologia , Receptor 2 Toll-Like/imunologia , Receptor 3 Toll-Like/imunologia
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