RESUMEN
Helminth parasites are a highly successful group of pathogens that challenge the immune system in a manner distinct from rapidly replicating infectious agents. Of this group, roundworms (nematodes) that dwell in the intestines of humans and other animals are prevalent worldwide. Currently, more than one billion people are infected by at least one species, often for extended periods of time. Thus, host-protective immunity is rarely complete. The reasons for this are complex, but laboratory investigation of tractable model systems in which protective immunity is effective has provided a mechanistic understanding of resistance that is characterized almost universally by a type 2/T helper 2 response. Greater understanding of the mechanisms of susceptibility has also provided the basis for defining host immunoregulation and parasite-evasion strategies, helping place in context the changing patterns of immunological disease observed worldwide.
Asunto(s)
Helmintiasis/inmunología , Helmintiasis/parasitología , Helmintos/inmunología , Interacciones Huésped-Patógeno/inmunología , Inmunidad Adaptativa , Animales , Antígenos Helmínticos/inmunología , Resistencia a la Enfermedad , Susceptibilidad a Enfermedades , Enfermedades Gastrointestinales/inmunología , Enfermedades Gastrointestinales/microbiología , Enfermedades Gastrointestinales/parasitología , Microbioma Gastrointestinal , Humanos , Inmunidad Innata , Nematodos/inmunología , Infecciones por Nematodos/inmunología , Infecciones por Nematodos/microbiología , Infecciones por Nematodos/parasitologíaRESUMEN
The eggs of the blood fluke Schistosoma mansoni are the main cause of the clinical manifestations of chronic schistosomiasis. After laying, the egg "winners" attach to the endothelium of the mesenteric vein and, after a period of development, induce the growth of a small granuloma, which facilitates their passage to the intestinal lumen. Egg "losers" carried by the bloodstream to non-specific tissues also undergo full development and induce large granuloma formation, but their life ends there. Although these trapped eggs represent a dead end in the parasite life cycle, the vast majority of studies attempting to describe the biology of the S. mansoni eggs have studied these liver-trapped "losers" instead of migrating intestinal "winners". This raises the fundamental question of how these eggs differ. With robust comparative transcriptomic analysis performed on S. mansoni eggs isolated 7 weeks post infection, we show that gene expression is critically dependent on tissue localization, both in the early and late stages of development. While mitochondrial genes and venom allergen-like proteins are significantly upregulated in mature intestinal eggs, well-described egg immunomodulators IPSE/alpha-1 and omega-1, together with micro-exon genes, are predominantly expressed in liver eggs. In addition, several proteases and protease inhibitors previously implicated in egg-host interactions display clear tissue-specific gene expression patterns. These major differences in gene expression could be then reflected in the observed different ability of liver and intestinal soluble egg antigens to elicit host immune responses and in the shorter viability of miracidia hatched from liver eggs. Our comparative analysis provides a new perspective on the biology of parasite's eggs in the context of their development and tissue localization. These findings could contribute to a broader and more accurate understanding of parasite eggs interactions with the host, which have historically been often restricted to liver eggs and sometimes inaccurately generalized.
Asunto(s)
Hígado , Schistosoma mansoni , Esquistosomiasis mansoni , Animales , Schistosoma mansoni/inmunología , Schistosoma mansoni/genética , Hígado/parasitología , Hígado/inmunología , Hígado/metabolismo , Esquistosomiasis mansoni/inmunología , Esquistosomiasis mansoni/parasitología , Ratones , Óvulo/metabolismo , Óvulo/inmunología , Intestinos/parasitología , Intestinos/inmunología , Antígenos Helmínticos/inmunología , Proteínas del Helminto/genética , Proteínas del Helminto/metabolismo , Proteínas del Helminto/inmunología , Femenino , Proteínas del HuevoRESUMEN
Laboratory model organisms have provided a window into how the immune system functions. An increasing body of evidence, however, suggests that the immune responses of naive laboratory animals may differ substantially to those of their wild counterparts. Past exposure, environmental challenges and physiological condition may all impact on immune responsiveness. Chronic infections of soil-transmitted helminths, which we define as establishment of adult, fecund worms, impose significant health burdens on humans, livestock and wildlife, with limited treatment success. In laboratory mice, Th1 versus Th2 immune polarisation is the major determinant of helminth infection outcome. Here we compared antigen-specific immune responses to the soil-transmitted whipworm Trichuris muris between controlled laboratory and wild free-ranging populations of house mice (Mus musculus domesticus). Wild mice harbouring chronic, low-level infections produced lower levels of cytokines in response to Trichuris antigen than laboratory-housed C57BL/6 mice. Wild mouse effector/memory CD4+ T cell phenotype reflected the antigen-specific cytokine response across the Th1/Th2 spectrum. Increasing egg shedding was associated with body condition loss. However, local Trichuris-specific Th1/Th2 balance was positively associated with worm burden only in older wild mice. Thus, although the fundamental relationships between the CD4+ T helper cell response and resistance to T. muris infection are similar in both laboratory and wild M. m. domesticus, there are quantitative differences and age-specific effects that are analogous to human immune responses. These context-dependent immune responses demonstrate the fundamental importance of understanding the differences between model and natural systems for translating mechanistic models to 'real world' immune function.
Asunto(s)
Inmunidad Adaptativa , Ratones Endogámicos C57BL , Tricuriasis , Trichuris , Animales , Trichuris/inmunología , Tricuriasis/inmunología , Tricuriasis/parasitología , Ratones , Inmunidad Adaptativa/inmunología , Modelos Animales de Enfermedad , Femenino , Animales Salvajes/inmunología , Animales Salvajes/parasitología , Células Th2/inmunología , Citocinas/inmunología , Citocinas/metabolismo , Antígenos Helmínticos/inmunología , MasculinoRESUMEN
The immune system is increasingly recognized as an important regulator of tissue repair. We developed a regenerative immunotherapy from the helminth Schistosoma mansoni soluble egg antigen (SEA) to stimulate production of interleukin (IL)-4 and other type 2-associated cytokines without negative infection-related sequelae. The regenerative SEA (rSEA) applied to a murine muscle injury induced accumulation of IL-4-expressing T helper cells, eosinophils, and regulatory T cells and decreased expression of IL-17A in gamma delta (γδ) T cells, resulting in improved repair and decreased fibrosis. Encapsulation and controlled release of rSEA in a hydrogel further enhanced type 2 immunity and larger volumes of tissue repair. The broad regenerative capacity of rSEA was validated in articular joint and corneal injury models. These results introduce a regenerative immunotherapy approach using natural helminth derivatives.
Asunto(s)
Esquistosomiasis mansoni , Animales , Ratones , Esquistosomiasis mansoni/terapia , Citocinas/metabolismo , Schistosoma mansoni , Linfocitos T Colaboradores-Inductores , Antígenos Helmínticos , InmunoterapiaRESUMEN
The initiation of type 2 immune responses by the epithelial cell-derived cytokines IL-25, IL-33 and TSLP has been an area of extensive research in the past decade. Such studies have led to the identification of a new innate lymphoid subset that produces the canonical type 2 cytokines IL-5, IL-9 and IL-13 in response to IL-25 and IL-33. These group 2 or type 2 innate lymphoid cells (ILC2 cells) represent a critical source of type 2 cytokines in vivo and serve an important role in orchestrating the type 2 response to helminths and allergens. Further characterization of ILC2 cell biology will enhance the understanding of type 2 responses and may identify new treatments for asthma, allergies and parasitic infections. Interactions between ILC2 cells and the adaptive immune system, as well as examination of potential roles for ILC2 cells in the maintenance of homeostasis, promise to be particularly fruitful areas of future research.
Asunto(s)
Hipersensibilidad/inmunología , Inmunidad Innata/inmunología , Linfocitos/inmunología , Células Th2/inmunología , Inmunidad Adaptativa/inmunología , Animales , Antígenos Helmínticos/inmunología , Citocinas/inmunología , Citocinas/metabolismo , Humanos , Hipersensibilidad/metabolismo , Linfocitos/metabolismo , Modelos Inmunológicos , Células Th2/metabolismoRESUMEN
Schistosomiasis is a parasitic disease characterized by liver fibrosis, a process driven by the activation of hepatic stellate cells (HSCs) and subsequent collagen production. Previous studies from our laboratory have demonstrated the ability of Schistosoma japonicum protein P40 (SjP40) to inhibit HSCs activation and exert an antifibrotic effect. In this study, we aimed to elucidate the molecular mechanism underlying the inhibitory effect of recombinant SjP40 (rSjP40) on HSCs activation. Using a cell model in which rSjP40 inhibited LX-2 cell activation, we performed RNA-seq analyses and identified ATF3 as the most significantly altered gene. Further investigation revealed that rSjP40 inhibited HSCs activation partly by suppressing ATF3 activation. Knockdown of ATF3 in mouse liver significantly alleviated S. japonicum-induced liver fibrosis. Moreover, our results indicate that ATF3 is a direct target of microRNA-494-3p, a microRNA associated with anti-liver fibrosis effects. rSjP40 was found to downregulate ATF3 expression by upregulating microRNA-494-3p in LX-2 cells. This downregulation led to the inhibition of the expression of liver fibrosis proteins α-SMA and COL1A1, ultimately alleviating liver fibrosis caused by S. japonicum.
Asunto(s)
Factor de Transcripción Activador 3 , Proteínas del Helminto , Células Estrelladas Hepáticas , Cirrosis Hepática , MicroARNs , Schistosoma japonicum , Esquistosomiasis Japónica , Animales , Factor de Transcripción Activador 3/metabolismo , Factor de Transcripción Activador 3/genética , Células Estrelladas Hepáticas/metabolismo , Células Estrelladas Hepáticas/parasitología , Esquistosomiasis Japónica/parasitología , Esquistosomiasis Japónica/metabolismo , Esquistosomiasis Japónica/genética , Cirrosis Hepática/parasitología , Cirrosis Hepática/genética , Cirrosis Hepática/patología , Cirrosis Hepática/metabolismo , Ratones , Humanos , MicroARNs/genética , MicroARNs/metabolismo , Proteínas del Helminto/genética , Proteínas del Helminto/metabolismo , Actinas/metabolismo , Actinas/genética , Línea Celular , Regulación de la Expresión Génica , Hígado/metabolismo , Hígado/parasitología , Hígado/patología , Modelos Animales de Enfermedad , Antígenos HelmínticosRESUMEN
BACKGROUND: The Global Programme to Eliminate Lymphatic Filariasis (GPELF) aims to reduce and maintain infection levels through mass drug administration (MDA), but there is evidence of ongoing transmission after MDA in areas where Culex mosquitoes are the main transmission vector, suggesting that a more stringent criterion is required for MDA decision making in these settings. METHODS: We use a transmission model to investigate how a lower prevalence threshold (<1% antigenemia [Ag] prevalence compared with <2% Ag prevalence) for MDA decision making would affect the probability of local elimination, health outcomes, the number of MDA rounds, including restarts, and program costs associated with MDA and surveys across different scenarios. To determine the cost-effectiveness of switching to a lower threshold, we simulated 65% and 80% MDA coverage of the total population for different willingness to pay per disability-adjusted life-year averted for India ($446.07), Tanzania ($389.83), and Haiti ($219.84). RESULTS: Our results suggest that with a lower Ag threshold, there is a small proportion of simulations where extra rounds are required to reach the target, but this also reduces the need to restart MDA later in the program. For 80% coverage, the lower threshold is cost-effective across all baseline prevalences for India, Tanzania, and Haiti. For 65% MDA coverage, the lower threshold is not cost-effective due to additional MDA rounds, although it increases the probability of local elimination. Valuing the benefits of elimination to align with the GPELF goals, we find that a willingness to pay per capita government expenditure of approximately $1000-$4000 for 1% increase in the probability of local elimination would be required to make a lower threshold cost-effective. CONCLUSIONS: Lower Ag thresholds for stopping MDAs generally mean a higher probability of local elimination, reducing long-term costs and health impacts. However, they may also lead to an increased number of MDA rounds required to reach the lower threshold and, therefore, increased short-term costs. Collectively, our analyses highlight that lower target Ag thresholds have the potential to assist programs in achieving lymphatic filariasis goals.
Asunto(s)
Análisis Costo-Beneficio , Filariasis Linfática , Administración Masiva de Medicamentos , Filariasis Linfática/prevención & control , Filariasis Linfática/epidemiología , Filariasis Linfática/economía , Humanos , Administración Masiva de Medicamentos/economía , Haití/epidemiología , Tanzanía/epidemiología , Prevalencia , India/epidemiología , Animales , Erradicación de la Enfermedad/economía , Erradicación de la Enfermedad/métodos , Filaricidas/uso terapéutico , Filaricidas/administración & dosificación , Filaricidas/economía , Antígenos Helmínticos/sangre , CulexRESUMEN
Trichinellosis caused by Trichinella spiralis (T. spiralis) is a zoonotic disease that poses a substantial risk to human health. At present, vaccines used to prevent trichinellosis are effective, but the production of antibody levels and immunogenicity are low. Adjuvants can increase antibody levels and vaccine immunogenicity. As a result, it is critical to develop an effective adjuvant for the T. spiralis vaccine. Recent research has shown that traditional Chinese medicine polysaccharides with low-toxicity and biodegradability can act as adjuvants in vaccines. In this study, BALB/c mice were orally inoculated with a recombinant Lactobacillus plantarum (L. plantarum) vaccine expressing the T. spiralis cathepsin F-like protease 1 gene (rTs-CPF1), which was given three times at 10-day intervals. Lycium barbarum polysaccharide (LBP) was administered orally for 37 days. At 37 days after the first immunization, mice were infected with 350 T. spiralis muscle larvae (ML). Specific IgG and sIgA antibody levels against the T. spiralis CPF1 protein were increased in mice immunized with rTs-CPF1+LBP compared to those immunized with rTs-CPF1 alone. Furthermore, LBP increased IFN-γ and IL-4 expression levels, and the number of intestinal and intramuscular worms was significantly reduced in the rTs-CPF1+LBP group compared to that in the rTs-CPF1 group. In the rTs-CPF1+LBP group, the reduction rates of adult worms and muscle larvae were 47.31 % and 68.88 %, respectively. To summarize, LBP promotes the immunoprotective effects of the T. spiralis vaccine and may be considered as a novel adjuvant in parasitic vaccines.
Asunto(s)
Lactobacillus plantarum , Trichinella spiralis , Triquinelosis , Ratones , Humanos , Animales , Trichinella spiralis/genética , Triquinelosis/prevención & control , Triquinelosis/parasitología , Catepsina F , Lactobacillus plantarum/genética , Antígenos Helmínticos/genética , Vacunas Sintéticas , Adyuvantes Inmunológicos/farmacología , Ratones Endogámicos BALB CRESUMEN
The two major lineages of classical dendritic cells (cDCs) express and require either IRF8 or IRF4 transcription factors for their development and function. IRF8-dependent cDCs promote anti-viral and T-helper 1 (Th1) cell responses, whereas IRF4-expressing cDCs have been implicated in controlling both Th2 and Th17 cell responses. Here, we have provided evidence that Kruppel-like factor 4 (Klf4) is required in IRF4-expressing cDCs to promote Th2, but not Th17, cell responses in vivo. Conditional Klf4 deletion within cDCs impaired Th2 cell responses during Schistosoma mansoni infection, Schistosoma egg antigen (SEA) immunization, and house dust mite (HDM) challenge without affecting cytotoxic T lymphocyte (CTL), Th1 cell, or Th17 cell responses to herpes simplex virus, Toxoplasma gondii, and Citrobacter rodentium infections. Further, Klf4 deletion reduced IRF4 expression in pre-cDCs and resulted in selective loss of IRF4-expressing cDCs subsets in several tissues. These results indicate that Klf4 guides a transcriptional program promoting IRF4-expressing cDCs heterogeneity.
Asunto(s)
Células Dendríticas/inmunología , Factores de Transcripción de Tipo Kruppel/genética , Factores de Transcripción de Tipo Kruppel/metabolismo , Esquistosomiasis mansoni/inmunología , Células Th2/inmunología , Animales , Antígenos Helmínticos/inmunología , Asma/inmunología , Células Cultivadas , Células Dendríticas/metabolismo , Modelos Animales de Enfermedad , Infecciones por Enterobacteriaceae/inmunología , Eliminación de Gen , Regulación de la Expresión Génica/genética , Regulación de la Expresión Génica/inmunología , Herpes Simple/inmunología , Factores Reguladores del Interferón/genética , Factores Reguladores del Interferón/inmunología , Factor 4 Similar a Kruppel , Ratones , Ratones Endogámicos C57BL , Pyroglyphidae , Células Th2/citología , Toxoplasmosis/inmunologíaRESUMEN
We aimed to develop an indirect enzyme-linked immunosorbent assay (ELISA) to evaluate the presence of specific IgG against Toxocara canis and Toxocara cati somatic antigens on the serum of patients with toxocariasis. The sensitivity, specificity, positive and negative predictive values for indirect-ELISA were calculated by receiver operating characteristic curve (ROC) analysis and Youden's J using Likelihood ratio. All statistics were analysed and graphs are plotted using GraphPad Prism version 8.4.3 (Graph Pad Software, La Jolla, CA, USA), with 95% confidence interval (CI). The sensitivity, specificity, positive and negative predictive values for T. canis were 100%, 82%, 79% and 100%, respectively. The mentioned variables for T. cati were 97%, 82%, 78% and 98%, respectively. Five immune reactive bands of 38, 40, 72, 100 and 250 kDa were common in both species. Toxocara crude antigens were highly immunogenic in human sera. Immunoreactive bands against T. canis compared to T. cati somatic antigen were about two times more. Unlike Toxocara excretory-secretory antigen, that was homologue in two species, somatic antigens of T. canis and T. cati showed different immunoreactive bands in our western blot.
Asunto(s)
Anticuerpos Antihelmínticos , Antígenos Helmínticos , Ensayo de Inmunoadsorción Enzimática , Inmunoglobulina G , Sensibilidad y Especificidad , Toxocara canis , Toxocara , Toxocariasis , Humanos , Animales , Antígenos Helmínticos/inmunología , Antígenos Helmínticos/sangre , Toxocariasis/inmunología , Toxocariasis/diagnóstico , Toxocariasis/sangre , Toxocara/inmunología , Anticuerpos Antihelmínticos/sangre , Ensayo de Inmunoadsorción Enzimática/métodos , Inmunoglobulina G/sangre , Toxocara canis/inmunología , Adulto , Valor Predictivo de las Pruebas , Curva ROC , Femenino , MasculinoRESUMEN
Trichinella spiralis (T. spiralis) is an immunomodulating parasite that can adversely affect tumor growth and extend host lifespan. The aim of this study was to elucidate the mechanisms by which T. spiralis larval antigens achieve this effect using Ehrlich solid carcinoma (ESC) murine model. Assessment was done by histopathological and immunohistochemical analysis of caspase-3, TNF-α, Ki-67 and CD31. Additionally, Bcl2 and Bcl2-associated protein X (Bax) relative gene expression was assessed by molecular analysis for studying the effect of T. spiralis crude larval extract (CLE) antigen on tumor necrosis, apoptosis, cell proliferation and angiogenesis. We found that both T. spiralis infection and CLE caused a decrease in the areas of necrosis in ESC. Moreover, they led to increased apoptosis through activation of caspase-3, up-regulation of pro-apoptotic gene, Bax and down-regulation of anti-apoptotic gene, Bcl2. Also, T. spiralis infection and CLE diminished ESC proliferation, as evidenced by decreasing Ki-67. T. spiralis infection and CLE were able to suppress the development of ESC by inhibiting tumor proliferation, inducing apoptosis and decreasing tumor necrosis, with subsequent decrease in tumor metastasis. T. spiralis CLE antigen may be considered as a promising complementary immunotherapeutic agent in the treatment of cancer.
Asunto(s)
Carcinoma de Ehrlich , Larva , Trichinella spiralis , Animales , Trichinella spiralis/efectos de los fármacos , Ratones , Larva/efectos de los fármacos , Carcinoma de Ehrlich/tratamiento farmacológico , Carcinoma de Ehrlich/patología , Carcinoma de Ehrlich/inmunología , Apoptosis/efectos de los fármacos , Proliferación Celular/efectos de los fármacos , Modelos Animales de Enfermedad , Antígenos Helmínticos/inmunología , Caspasa 3/metabolismo , Proteína X Asociada a bcl-2/metabolismo , Antígeno Ki-67/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/metabolismo , Proteínas Proto-Oncogénicas c-bcl-2/genética , Factor de Necrosis Tumoral alfa/metabolismo , Antineoplásicos/farmacología , Antineoplásicos/uso terapéutico , Femenino , InmunohistoquímicaRESUMEN
Trichinella spiralis (T. spiralis) is a zoonotic parasitic nematode with a unique life cycle, as all developmental stages are contained within a single host. Excretory-secretory (ES) proteins are the main targets of the interactions between T. spiralis and the host at different stages of development and are essential for parasite survival. However, the ES protein profiles of T. spiralis at different developmental stages have not been characterized. The proteomes of ES proteins from different developmental stages, namely, muscle larvae (ML), intestinal infective larvae (IIL), preadult (PA) 6 h, PA 30 h, adult (Ad) 3 days post-infection (dpi) and Ad 6 dpi, were characterized via label-free mass spectrometry analysis in combination with bioinformatics. A total of 1217 proteins were identified from 9341 unique peptides in all developmental stages, 590 of which were quantified and differentially expressed. GO classification and KEGG pathway analysis revealed that these proteins were important for the growth of the larvae and involved in energy metabolism. Moreover, the heat shock cognate 71 kDa protein was the centre of protein interactions at different developmental stages. The results of this study provide comprehensive proteomic data on ES proteins and reveal that these ES proteins were differentially expressed at different developmental stages. Differential proteins are associated with parasite survival and the host immune response and may be potential early diagnostic antigen or antiparasitic vaccine candidates.
Asunto(s)
Trichinella spiralis , Trichinella , Triquinelosis , Animales , Triquinelosis/veterinaria , Proteínas del Helminto/metabolismo , Proteómica , Músculos , Larva/metabolismo , Antígenos Helmínticos , Trichinella/metabolismoRESUMEN
BACKGROUND: Porcine cysticercosis, a serious zoonotic parasitic disease, is caused by the larvae of Taenia solium and has been acknowledged by the World Organization for Animal Health. The current detection methods of Cysticercus cellulosae cannot meet the needs of large-scale and rapid detection in the field. We hypothesized that the immunofluorescence chromatography test strip (ICS) for detecting Cysticercus cellulosae, according to optimization of a series of reaction systems was conducted, and sensitivity, specificity, and stability testing, and was finally compared with ELISA. This method utilizes Eu3+-labeled time-resolved fluorescent microspheres (TRFM) coupled with TSOL18 antigen to detect TSOL18 antibodies in infected pig sera. RESULTS: ICS and autopsy have highly consistent diagnostic results (n = 133), as determined by Cohen's κ analysis (κ = 0.925). And the results showed that the proposed ICS are high sensitivity (0.9459) with specificity (0.9792). The ICS was unable to detect positive samples of other parasites. It can be stored for at least six months at 4â. CONCLUSIONS: In summary, we established a TRFM-ICS method with higher sensitivity and specificity than indirect ELISA. Results obtained from serum samples can be read within 10 min, indicating a rapid, user-friendly test suitable for large-scale field detection.
Asunto(s)
Anticuerpos Antihelmínticos , Antígenos Helmínticos , Cisticercosis , Ensayo de Inmunoadsorción Enzimática , Técnica del Anticuerpo Fluorescente , Sensibilidad y Especificidad , Enfermedades de los Porcinos , Animales , Porcinos , Enfermedades de los Porcinos/diagnóstico , Enfermedades de los Porcinos/parasitología , Enfermedades de los Porcinos/sangre , Cisticercosis/veterinaria , Cisticercosis/diagnóstico , Anticuerpos Antihelmínticos/sangre , Antígenos Helmínticos/sangre , Antígenos Helmínticos/inmunología , Técnica del Anticuerpo Fluorescente/veterinaria , Técnica del Anticuerpo Fluorescente/métodos , Ensayo de Inmunoadsorción Enzimática/veterinaria , Ensayo de Inmunoadsorción Enzimática/métodos , Cysticercus/inmunología , Taenia solium/inmunologíaRESUMEN
Human cysticercosis caused by Taenia soliun (T. soliun) is endemic in certain areas of Latin America, Asia and Sub-Saharan Africa. Neurocysticercosis (NCC) is mainly diagnosed by neuroimaging, which, in most cases, is unavailable in endemic areas. Due to their high sensitivity and specificity, serological tests such as enzyme-linked immunosorbent assay (ELISA) and Western blot (WB) based on the glycosylated fraction of the cyst CS50 are widely used for the detection of the anti-cysticercus IgG antibodies despite their significant cost and the need of cysticercus material. Given their cost-effectivess and simplicity, immunoassays based on recombinant proteins could provide new alternatives for human cysticercosis diagnosis: such tests would be aimed at screening those people living in remote areas who need further examination. To date, however, no test using recombinant antigens is commercially available. Herein, five recombinant proteins (R14, R18, R93.1, R914.1, and R915.2) were produced, three of which (R93.1, R914.1, and R915.2) were newly identified from the cyst fluid. Evaluation of the diagnostic performance of these recombinant antigens by ELISA was done using sera from 200 epileptic and non-epileptic individuals in comparison with the WB-CS50 as the reference serological method. Recombinant proteins-based ELISA showed a level of diagnostic performance that is inferior than the reference serological method, but similar to that of the native antigen ELISA for human cysticercosis (commonly used for screening). Further optimization of expression conditions is still needed in order to improve proteins solubility and enhance diagnostic performance for human cysticercosis detection. However, this preliminary evaluation of the recombinant antigens has shown their potential valuable use for screening cysticercosis in patients with epilepsy attending dispensaries in remote areas. Future studies should be conducted to evaluate our recombinant antigens in a large group of patients with different stages of NCC, and in correlation with imaging findings.
Asunto(s)
Anticuerpos Antihelmínticos , Antígenos Helmínticos , Western Blotting , Cisticercosis , Ensayo de Inmunoadsorción Enzimática , Proteínas Recombinantes , Sensibilidad y Especificidad , Taenia solium , Humanos , Proteínas Recombinantes/inmunología , Antígenos Helmínticos/inmunología , Antígenos Helmínticos/genética , Cisticercosis/diagnóstico , Animales , Taenia solium/inmunología , Taenia solium/genética , Anticuerpos Antihelmínticos/sangre , Inmunoglobulina G/sangre , Neurocisticercosis/diagnóstico , Neurocisticercosis/inmunología , Epilepsia/diagnóstico , Adulto , Masculino , Pruebas Serológicas/métodos , FemeninoRESUMEN
Timely and accurate diagnosis of Schistosoma infection is important to adopt effective strategies for schistosomiasis control. Previously, we demonstrated that Schistosoma japonicum can secret extracellular vesicles and their cargos may serve as a novel type of biomarkers for diagnosing schistosomiasis. Here, we developed a Gaussia luciferase immunoprecipitation assay combined with S. japonicum extracellular vesicle (SjEV) protein to evaluate its potential for diagnosing schistosomiasis. A saposin-like protein (SjSLP) identified from SjEVs was fused to the Gaussia luciferase as the diagnostic antigen. The developed method showed good capability for detecting S. japonicum infection in mice and human patients. We also observed that the method could detect Schistosoma infection in mice as early as 7 days of post-infection, which showed better sensitivity than that of indirect ELISA method. Overall, the developed method showed a good potential for detecting Schistosoma infection particularly for early stage, which may provide an alternative strategy for identify Schistosoma infection for disease control.
Asunto(s)
Inmunoprecipitación , Luciferasas , Schistosoma japonicum , Esquistosomiasis Japónica , Animales , Esquistosomiasis Japónica/diagnóstico , Esquistosomiasis Japónica/parasitología , Schistosoma japonicum/enzimología , Schistosoma japonicum/inmunología , Ratones , Humanos , Inmunoprecipitación/métodos , Luciferasas/genética , Femenino , Sensibilidad y Especificidad , Ratones Endogámicos BALB C , Ensayo de Inmunoadsorción Enzimática/métodos , Vesículas Extracelulares , Antígenos Helmínticos/análisis , Antígenos Helmínticos/inmunología , MasculinoRESUMEN
Opisthorchis viverrini infection and the subsequent bile duct cancer it induces remains a significant public health problem in Southeast Asia. Opisthorchiasis has been reported to cause reduced plasma glucose levels among infected patients. The underlying mechanism for this phenomenon is unclear. In the present study, evidence is presented to support the hypothesis that O. viverrini exploits host cholangiocyte glucose transporters (GLUTs) in a similar manner to that of rodent intestinal nematodes, to feed on unabsorbed glucose in the bile for survival. GLUT levels in a cholangiocyte H69 cell line co-cultured with excretory-secretory products of O. viverrini were examined using qPCR and immunoblotting. GLUT 8 mRNA and expressed proteins were found to be downregulated in H69 cells in the presence of O. viverrini. This suggests that O. viverrini alters glucose metabolism in cells within its vicinity by limiting transporter expression resulting in increased bile glucose that it can utilize and potentially explains the previously reported anti-insulin effect of opisthorchiasis.
Asunto(s)
Antígenos Helmínticos , Neoplasias de los Conductos Biliares , Opistorquiasis , Opisthorchis , Animales , Humanos , Neoplasias de los Conductos Biliares/metabolismo , Conductos Biliares Intrahepáticos , Glucosa/metabolismo , Opistorquiasis/complicaciones , Opistorquiasis/metabolismo , Opisthorchis/metabolismo , Antígenos Helmínticos/metabolismo , Proteínas Facilitadoras del Transporte de la Glucosa/metabolismoRESUMEN
Background: Inflammatory bowel disease is an autoimmune disease that affects the gut. T. spiralis larvae (E/S Ags) loaded on calcium-benzene-1,3,5-tricarboxylate metal-organic frameworks (Ca-BTC MOFs) were tested to determine whether they might prevent or cure acetic acid-induced murine colitis. Methods: T. spiralis larvae E/S Ags/Ca-BTC MOFs were used in prophylactic and therapeutic groups to either precede or follow the development of murine colitis. On the seventh day after colitis, mice were slaughtered. The effect of our target antigens on the progress of the colitis was evaluated using a variety of measures, including survival rate, disease activity index, colon weight/bodyweight, colon weight/length) ratios, and ratings for macroscopic and microscopic colon damage. The levels of inflammatory cytokines (interferon-γ and interleukin-4), oxidative stress marker malondialdehyde, and glutathione peroxidase in serum samples were evaluated. Foxp3 T-reg expression was carried out in colonic and splenic tissues. Results: T. spiralis larvae E/S Ags/Ca-BTC MOFs were the most effective in alleviating severe inflammation in murine colitis. The survival rate, disease activity index score, colon weight/length and colon weight/bodyweight ratios, and gross and microscopic colon damage scores have all considerably improved. A large decrease in proinflammatory cytokine (interferon-γ) and oxidative stress marker (malondialdehyde) expression and a significant increase in interleukin-4 and glutathione peroxidase expression were obtained. The expression of Foxp3+ Treg cells was elevated in colonic and splenic tissues. Conclusion: T. spiralis larvae E/S Ags/Ca-BTC MOFs had the highest anti-inflammatory, antioxidant, and cytoprotective capabilities against murine colitis and might be used to develop new preventative and treatment strategies.
Asunto(s)
Colitis , Citocinas , Larva , Estructuras Metalorgánicas , Trichinella spiralis , Animales , Ratones , Estructuras Metalorgánicas/química , Colitis/prevención & control , Colitis/inducido químicamente , Colitis/parasitología , Trichinella spiralis/inmunología , Antígenos Helmínticos/inmunología , Modelos Animales de Enfermedad , Colon/parasitología , Colon/patología , Ratones Endogámicos BALB C , Femenino , MasculinoRESUMEN
Trichinellosis is an important foodborne zoonosis, and no effective treatments are yet available. Nod-like receptor (NLR) plays a critical role in the host response against nematodes. Therefore, we aimed to explore the role of the NLRP3 inflammasome (NLRP3) during the adult, migrating, and encysted stages of Trichinella spiralis infection. The mice were treated with the specific NLRP3 inhibitor MCC950 after inoculation with T. spiralis. Then, the role that NLRP3 plays during T. spiralis infection of mice was evaluated using enzyme-linked immunosorbent assay (ELISA), Western blotting, flow cytometry, histopathological evaluation, bone marrow-derived macrophage (BMDM) stimulation, and immunofluorescence. The in vivo results showed that NLRP3 enhanced the Th1 immune response in the adult and migrating stages and weakened the Th2 immune response in the encysted stage. NLRP3 promoted the release of proinflammatory factors (interferon gamma [IFN-γ]) and suppressed the release of anti-inflammatory factors (interleukin 4 [IL-4]). Pathological changes were also improved in the absence of NLRP3 in mice during T. spiralis infection. Importantly, a significant reduction in adult worm burden and muscle larvae burden at 7 and 35 days postinfection was observed in mice treated with the specific NLRP3 inhibitor MCC950. In vitro, we first demonstrated that NLRP3 in macrophages can be activated by T. spiralis proteins and promotes IL-1ß and IL-18 release. This study revealed that NLRP3 is involved in the host response to T. spiralis infection and that targeted inhibition of NLRP3 enhanced the Th2 response and accelerated T. spiralis expulsion. These findings may help in the development of protocols for controlling trichinellosis.
Asunto(s)
Trichinella spiralis , Triquinelosis , Ratones , Animales , Proteína con Dominio Pirina 3 de la Familia NLR , Antígenos Helmínticos , Ratones Endogámicos BALB CRESUMEN
Neurocysticercosis prevalence estimates often are based on serosurveys. However, assessments of Taenia solium seropositivity durability in patients with various neurocysticercosis types are lacking. We optimized a triplex serologic ELISA by using synthetic GP50, T24H, and Ts18var3 antigens for T. solium. We used that assay to test sequential serologic responses over several years after neurocysticercosis cure in 46 patients, 9 each with parenchymal or ventricular neurocysticercosis and 28 with subarachnoid disease. Triplex results were concordant with 98% of positive and 100% of negative enzyme-linked immunoelectrotransfer blots. Eight years after neurocysticercosis cure, 11.1% of patients with parenchymal, 47.3% with subarachnoid, and 41.7% with ventricular disease were still seropositive. Median time to seroreversion after cure in this cohort in a T. solium nonendemic area was 2 years for parenchymal disease, 4 years for ventricular disease, and 8 years for subarachnoid disease. Our findings can inform epidemiologic models that rely on serosurveys to estimate disease burden.
Asunto(s)
Neurocisticercosis , Taenia solium , Taenia , Animales , Humanos , Neurocisticercosis/diagnóstico , Neurocisticercosis/epidemiología , Antígenos Helmínticos , Anticuerpos Antihelmínticos , Ensayo de Inmunoadsorción Enzimática/métodosRESUMEN
Neurocysticercosis (NCC) is the most common helminthic infection of the human central nervous system. The antibody detection assay of choice is the enzyme-linked immunoelectrotransfer blot assay using lentil-lectin purified parasite antigens (LLGP-EITB, Western blot), an immunoassay with exceptional performance in clinical samples. However, its use is mainly restricted to a few research laboratories because the assay is labor-intensive and requires sophisticated equipment, expertise, and large amounts of parasite material for preparation of reagents. We report a new immunoprint assay (MAPIA) that overcomes most of these barriers. We initially compared the performance of five different antigen combinations in a subset of defined samples in the MAPIA format. After selecting the best-performing assay format (a combination of rGP50 + rT24H + sTs14 antigens), 148 archived serum samples were tested, including 40 from individuals with parenchymal NCC, 40 with subarachnoid NCC, and 68 healthy controls with no evidence of neurologic disease. MAPIA using three antigens (rGP50 + rT24H + sTs14) was highly sensitive and specific for detecting antibodies in NCC. It detected 39 out of 40 (97.5%) parenchymal NCC cases and 40/40 (100%) subarachnoid cases and was negative in 67 out of 68 (98.53%) negative samples. MAPIA using three recombinant and synthetic antigens is a simple and economical tool with a performance equivalent to the LLGP-EITB assay for the detection of specific antibodies to NCC. The MAPIA overcomes existing barriers to adoption of the EITG LLGP and is a candidate for worldwide use.