RESUMO
OBJECTIVE: Schistosomiasis is a neglected tropical parasitic disease caused by blood flukes of the genus Schistosoma. Schistosoma japonicum is zoonotic in China, the Philippines, and Indonesia, with bovines acting as major reservoirs of human infection. The primary objective of the trial was to examine the impact of a combination of human mass chemotherapy, snail control through mollusciciding, and SjCTPI bovine vaccination on the rate of human infection. METHODS: A 5-year phase IIIa cluster randomized control trial was conducted among 18 schistosomiasis-endemic villages comprising 18,221 residents in Northern Samar, The Philippines. RESULTS: Overall, bovine vaccination resulted in a statistically significant decrease in human infection (relative risk [RR] = 0.75; 95% confidence interval [CI] = 0.69 to 0.82) across all trial follow-ups. The best outcome of the trial was when bovine vaccination was combined with snail mollusciciding. This combination resulted in a 31% reduction (RR = 0.69; 95% CI = 0.61 to 0.78) in human infection. CONCLUSION: This is the first trial to demonstrate the effectiveness of a bovine vaccine for schistosomiasis in reducing human schistosome infection. The trial is registered with Australian New Zealand Clinical Trials Registry (ACTRN12619001048178).
Assuntos
Schistosoma japonicum , Esquistossomose Japônica , Esquistossomose , Vacinas , Animais , Humanos , Bovinos , Esquistossomose Japônica/epidemiologia , Esquistossomose Japônica/prevenção & controle , Esquistossomose Japônica/veterinária , Austrália , Esquistossomose/epidemiologia , Esquistossomose/prevenção & controle , China , Caramujos/parasitologiaRESUMO
Chemical overexposures and war-related stress during the 1990-1991 Gulf War (GW) are implicated in the persisting pathological symptoms that many GW veterans continue to endure. These symptoms culminate into a disease known as Gulf War Illness (GWI) and affect about a third of the GW veteran population. Currently, comprehensive effective GWI treatment options are unavailable. Here, an established GWI mouse model was utilized to explore the (1) long-term behavioral and neuroinflammatory effects of deployment-related GWI chemicals exposure and (2) ability of the immunotherapeutic lacto-N-fucopentaose III (LNFPIII) to improve deficits when given months after the end of exposure. Male C57BL6/J mice (8-9 weeks old) were administered pyridostigmine bromide (PB) and DEET for 14 days along with corticosterone (CORT; latter 7 days) to emulate wartime stress. On day 15, a single injection of the nerve agent surrogate diisopropylfluorophosphate (DFP) was given. LNFPIII treatment began 7 months post GWI chemicals exposure and continued until study completion. A battery of behavioral tests for assessment of cognition/memory, mood, and motor function in rodents was performed beginning 8 months after exposure termination and was then followed by immunohistochemcal evaluation of neuroinflammation and neurogenesis. Within tests of motor function, prior GWI chemical exposure led to hyperactivity, impaired sensorimotor function, and altered gait. LNFPIII attenuated these motor-related deficits and improved overall grip strength. GWI mice also exhibited more anxiety-like behavior that was reduced by LNFPIII; this was test-specific. Short-term, but not long-term memory, was impaired by prior GWI exposure; LNFPIII improved this measure. In the brains of GWI mice, but not in mice treated with LNFPIII, glial activation was increased. Overall, it appears that months after exposure to GWI chemicals, behavioral deficits and neuroinflammation are present. Many of these deficits were attenuated by LNFPIII when treatment began long after GWI chemical exposure termination, highlighting its therapeutic potential for veterans with GWI.
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BACKGROUND: Sporozoites isolated from the salivary glands of Plasmodium-infected mosquitoes are a prerequisite for several basic and pre-clinical applications. Although salivary glands are pooled to maximize sporozoite recovery, insufficient yields pose logistical and analytical hurdles; thus, predicting yields prior to isolation would be valuable. Preceding oocyst densities in the midgut is an obvious candidate. However, it is unclear whether current understanding of its relationship with sporozoite densities can be used to maximize yields, or whether it can capture the potential density-dependence in rates of sporozoite invasion of the salivary glands. METHODS: This study presents a retrospective analysis of Anopheles stephensi mosquitoes infected with two strains of the rodent-specific Plasmodium berghei. Mean oocyst densities were estimated in the midguts earlier in the infection (11-15 days post-blood meal), with sporozoites pooled from the salivary glands later in the infection (17-29 days). Generalized linear mixed effects models were used to determine if (1) mean oocyst densities can predict sporozoite yields from pooled salivary glands, (2) whether these densities can capture differences in rates of sporozoite invasion of salivary glands, and (3), if the interaction between oocyst densities and time could be leveraged to boost overall yields. RESULTS: The non-linear effect of mean oocyst densities confirmed the role of density-dependent constraints in limiting yields beyond certain oocyst densities. Irrespective of oocyst densities however, the continued invasion of salivary glands by the sporozoites boosted recoveries over time (17-29 days post-blood meal) for either parasite strain. CONCLUSIONS: Sporozoite invasion of the salivary glands over time can be leveraged to maximize yields for P. berghei. In general, however, invasion of the salivary glands over time is a critical fitness determinant for all Plasmodium species (extrinsic incubation period, EIP). Thus, delaying sporozoite collection could, in principle, substantially reduce dissection effort for any parasite within the genus, with the results also alluding to the potential for changes in sporozoites densities over time to modify infectivity for the next host.
Assuntos
Anopheles , Esporozoítos , Animais , Anopheles/parasitologia , Plasmodium berghei , Estudos Retrospectivos , Glândulas Salivares/parasitologiaRESUMO
Residual effects of the 1990-1991 Gulf War (GW) still plague veterans 30 years later as Gulf War Illness (GWI). Thought to stem mostly from deployment-related chemical overexposures, GWI is a disease with multiple neurological symptoms with likely immunological underpinnings. Currently, GWI remains untreatable, and the long-term neurological disease manifestation is not characterized fully. The present study sought to expand and evaluate the long-term implications of prior GW chemicals exposure on neurological function 6-8 months post GWI-like symptomatology induction. Additionally, the beneficial effects of delayed treatment with the glycan immunotherapeutic lacto-N-fucopentaose III (LNFPIII) were evaluated. Male C57BL/6J mice underwent a 10-day combinational exposure (i.p.) to GW chemicals, the nerve agent prophylactic pyridostigmine bromide (PB) and the insecticide permethrin (PM; 0.7 and 200 mg/kg, respectively). Beginning 4 months after PB/PM exposure, a subset of the mice were treated twice a week until study completion with LNFPIII. Evaluation of cognition/memory, motor function, and mood was performed beginning 1 month after LNFPIII treatment initiation. Prior exposure to PB/PM produced multiple locomotor, neuromuscular, and sensorimotor deficits across several motor tests. Subtle anxiety-like behavior was also present in PB/PM mice in mood tests. Further, PB/PM-exposed mice learned at a slower rate, mostly during early phases of the learning and memory tests employed. LNFPIII treatment restored or improved many of these behaviors, particularly in motor and cognition/memory domains. Electrophysiology data collected from hippocampal slices 8 months post PB/PM exposure revealed modest aberrations in basal synaptic transmission and long-term potentiation in the dorsal or ventral hippocampus that were improved by LNFPIII treatment. Immunohistochemical analysis of tyrosine hydroxylase (TH), a dopaminergic marker, did not detect major PB/PM effects along the nigrostriatal pathway, but LNFPIII increased striatal TH. Additionally, neuroinflammatory cells were increased in PB/PM mice, an effect reduced by LNFPIII. Collectively, long-term neurobehavioral and neurobiological dysfunction associated with prior PB/PM exposure was characterized; delayed LNFPIII treatment provided multiple behavioral and biological beneficial effects in the context of GWI, highlighting its potential as a GWI therapeutic.
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Agentes Neurotóxicos/farmacologia , Síndrome do Golfo Pérsico/tratamento farmacológico , Polissacarídeos/farmacologia , Tempo para o Tratamento , Animais , Cognição/fisiologia , Modelos Animais de Doenças , Masculino , Camundongos Endogâmicos C57BL , Permetrina/farmacologia , Transmissão Sináptica/efeitos dos fármacosRESUMO
Obesity is the largest risk factor for the development of chronic diseases in industrialized countries. Excessive fat accumulation triggers a state of chronic low-grade inflammation to the detriment of numerous organs. To address this problem, our lab has been examining the anti-inflammatory mechanisms of two human milk oligosaccharides (HMOs), lacto-N-fucopentaose III (LNFPIII) and lacto-N-neotetraose (LNnT). LNFPIII and LNnT are HMOs that differ in structure via presence/absence of an α1,3-linked fucose. We utilize LNFPIII and LNnT in conjugate form, where 10-12 molecules of LNFPIII or LNnT are conjugated to a 40 kDa dextran carrier (P3DEX/NTDEX). Previous studies from our lab have shown that LNFPIII conjugates are anti-inflammatory, act on multiple cell types, and are therapeutic in a wide range of murine inflammatory disease models. The α1,3-linked fucose residue on LNFPIII makes it difficult and more expensive to synthesize. Therefore, we asked if LNnT conjugates induced similar therapeutic effects to LNFPIII. Herein, we compare the therapeutic effects of P3DEX and NTDEX in a model of diet-induced obesity (DIO). Male C57BL/6 mice were placed on a high-fat diet for six weeks and then injected twice per week for eight weeks with 25µg of 40 kDa dextran (DEX; vehicle control), P3DEX, or NTDEX. We found that treatment with P3DEX, but not NTDEX, led to reductions in body weight, adipose tissue (AT) weights, and fasting blood glucose levels. Mice treated with P3DEX also demonstrated improvements in glucose homeostasis and insulin tolerance. Treatment with P3DEX or NTDEX also induced different profiles of serum chemokines, cytokines, adipokines, and incretin hormones, with P3DEX notably reducing circulating levels of leptin and resistin. P3DEX also reduced WAT inflammation and hepatic lipid accumulation, whereas NTDEX seemed to worsen these parameters. These results suggest that the small structural difference between P3DEX and NTDEX has significant effects on the conjugates' therapeutic abilities. Future work will focus on identifying the receptors for these conjugates and delineating the mechanisms by which P3DEX and NTDEX exert their effects.
Assuntos
Amino Açúcares/farmacologia , Anti-Inflamatórios/farmacologia , Fármacos Antiobesidade/farmacologia , Dieta Hiperlipídica , Leite Humano , Obesidade/prevenção & controle , Oligossacarídeos/farmacologia , Polissacarídeos/farmacologia , Adipocinas/sangue , Tecido Adiposo/efeitos dos fármacos , Tecido Adiposo/metabolismo , Tecido Adiposo/fisiopatologia , Adiposidade/efeitos dos fármacos , Amino Açúcares/síntese química , Animais , Anti-Inflamatórios/síntese química , Fármacos Antiobesidade/síntese química , Glicemia/efeitos dos fármacos , Glicemia/metabolismo , Citocinas/sangue , Modelos Animais de Doenças , Mediadores da Inflamação/sangue , Resistência à Insulina , Masculino , Camundongos Endogâmicos C57BL , Leite Humano/química , Estrutura Molecular , Obesidade/sangue , Obesidade/etiologia , Obesidade/fisiopatologia , Oligossacarídeos/síntese química , Polissacarídeos/síntese química , Relação Estrutura-Atividade , Aumento de Peso/efeitos dos fármacosRESUMO
AIMS: The present study investigated if treatment with the immunotherapeutic, lacto-N-fucopentaose-III (LNFPIII), resulted in amelioration of acute and persisting deficits in synaptic plasticity and transmission as well as trophic factor expression along the hippocampal dorsoventral axis in a mouse model of Gulf War Illness (GWI). MAIN METHODS: Mice received either coadministered or delayed LNFPIII treatment throughout or following, respectively, exposure to a 15-day GWI induction paradigm. Subsets of animals were subsequently sacrificed 48 h, seven months, or 11 months post GWI-related (GWIR) exposure for hippocampal qPCR or in vitro electrophysiology experiments. KEY FINDINGS: Progressively worsened impairments in hippocampal synaptic plasticity, as well as a biphasic effect on hippocampal synaptic transmission, were detected in GWIR-exposed animals. Dorsoventral-specific impairments in hippocampal synaptic responses became more pronounced over time, particularly in the dorsal hippocampus. Notably, delayed LNFPIII treatment ameliorated GWI-related aberrations in hippocampal synaptic plasticity and transmission seven and 11 months post-exposure, an effect that was consistent with enhanced hippocampal trophic factor expression and absence of increased interleukin 6 (IL-6) in animals treated with LNFPIII. SIGNIFICANCE: Approximately a third of Gulf War Veterans have GWI; however, GWI therapeutics are presently limited to targeted and symptomatic treatments. As increasing evidence underscores the substantial role of persisting neuroimmune dysfunction in GWI, efficacious neuroactive immunotherapeutics hold substantial promise in yielding GWI remission. The findings in the present report indicate that LNFPIII may be an efficacious candidate for ameliorating persisting neurological abnormalities presented in GWI.
Assuntos
Amino Açúcares/farmacologia , Modelos Animais de Doenças , Hipocampo/efeitos dos fármacos , Plasticidade Neuronal/efeitos dos fármacos , Síndrome do Golfo Pérsico/prevenção & controle , Polissacarídeos/farmacologia , Transmissão Sináptica/efeitos dos fármacos , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Síndrome do Golfo Pérsico/etiologia , Síndrome do Golfo Pérsico/patologiaRESUMO
Approximately one-third of Persian Gulf War veterans are afflicted by Gulf War Illness (GWI), a chronic multisymptom condition that fundamentally presents with cognitive deficits (i.e., learning and memory impairments) and neuroimmune dysfunction (i.e., inflammation). Factors associated with GWI include overexposures to neurotoxic pesticides and nerve agent prophylactics such as permethrin (PM) and pyridostigmine bromide (PB), respectively. GWI-related neurological impairments associated with PB-PM overexposures have been recapitulated in animal models; however, there is a paucity of studies assessing PB-PM-related aberrations in hippocampal synaptic plasticity and transmission that may underlie behavioral impairments. Importantly, FDA-approved neuroactive treatments are currently unavailable for GWI. In the present study, we assessed the efficacy of an immunomodulatory therapeutic, lacto-N-fucopentaose-III (LNFPIII), on ameliorating acute effects of in vivo PB-PM exposure on synaptic plasticity and transmission as well as trophic factor/cytokine expression along the hippocampal dorsoventral axis. PB-PM exposure resulted in hippocampal synaptic transmission deficits 48 h post-exposure, a response that was ameliorated by LNFPIII coadministration, particularly in the dorsal hippocampus (dH). LNFPIII coadministration also enhanced synaptic transmission in the dH and the ventral hippocampus (vH). Notably, LNFPIII coadministration elevated long-term potentiation in the dH. Further, PB-PM exposure and LNFPIII coadministration uniquely altered key inflammatory cytokine and trophic factor production in the dH and the vH. Collectively, these findings demonstrate that PB-PM exposure impaired hippocampal synaptic responses 48 h post-exposure, impairments that differentially manifested along the dorsoventral axis. Importantly, LNFPIII ameliorated GWI-related electrophysiological deficits, a beneficial effect indicating the potential efficacy of LNFPIII for treating GWI.
Assuntos
Amino Açúcares/uso terapêutico , Modelos Animais de Doenças , Hipocampo/fisiopatologia , Síndrome do Golfo Pérsico/tratamento farmacológico , Síndrome do Golfo Pérsico/fisiopatologia , Polissacarídeos/uso terapêutico , Transmissão Sináptica/fisiologia , Amino Açúcares/farmacologia , Animais , Dimetil Sulfóxido/toxicidade , Potenciais Pós-Sinápticos Excitadores/efeitos dos fármacos , Potenciais Pós-Sinápticos Excitadores/fisiologia , Hipocampo/efeitos dos fármacos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Plasticidade Neuronal/efeitos dos fármacos , Plasticidade Neuronal/fisiologia , Técnicas de Cultura de Órgãos , Material Particulado/toxicidade , Síndrome do Golfo Pérsico/induzido quimicamente , Polissacarídeos/farmacologia , Transmissão Sináptica/efeitos dos fármacosRESUMO
The microbiota's influence on host (patho) physiology has gained interest in the context of Gulf War Illness (GWI), a chronic disorder featuring dysregulation of the gut-brain-immune axis. This study examined short- and long-term effects of GWI-related chemicals on gut health and fecal microbiota and the potential benefits of Lacto-N-fucopentaose-III (LNFPIII) treatment in a GWI model. Male C57BL/6J mice were administered pyridostigmine bromide (PB; 0.7 mg/kg) and permethrin (PM; 200 mg/kg) for 10 days with concurrent LNFPIII treatment (35 µg/mouse) in a short-term study (12 days total) and delayed LNFPIII treatment (2×/week) beginning 4 months after 10 days of PB/PM exposure in a long-term study (9 months total). Fecal 16S rRNA sequencing was performed on all samples post-LNFPIII treatment to assess microbiota effects of GWI chemicals and acute/delayed LNFPIII administration. Although PB/PM did not affect species composition on a global scale, it affected specific taxa in both short- and long-term settings. PB/PM elicited more prominent long-term effects, notably, on the abundances of bacteria belonging to Lachnospiraceae and Ruminococcaceae families and the genus Allobaculum. LNFPIII improved a marker of gut health (i.e., decreased lipocalin-2) independent of GWI and, importantly, increased butyrate producers (e.g., Butyricoccus, Ruminococcous) in PB/PM-treated mice, indicating a positive selection pressure for these bacteria. Multiple operational taxonomic units correlated with aberrant behavior and lipocalin-2 in PB/PM samples; LNFPIII was modulatory. Overall, significant and lasting GWI effects occurred on specific microbiota and LNFPIII treatment was beneficial.
Assuntos
Microbioma Gastrointestinal , Síndrome do Golfo Pérsico , Amino Açúcares/química , Animais , Guerra do Golfo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Polissacarídeos/química , RNA Ribossômico 16S/genéticaRESUMO
Monoclonal antibodies (mAbs) that recognize glycans are useful tools to assess carbohydrates' structure and function. We sought to produce IgG mAbs to the human milk oligosaccharide (HMO), lacto-N-fucopentaose III (LNFPIII). LNFPIII contains the Lewisx antigen, which is found on the surface of schistosome parasites. mAbs binding the Lewisx antigen are well-reported in the literature, but mAbs recognizing HMO structures are rare. To generate mAbs, mice were immunized with LNFPIII-DEX (P3DEX) plus CpGs in VacSIM®, a novel vaccine/drug delivery platform. Mice were boosted with LNFPIII-HSA (P3HSA) plus CpGs in Incomplete Freund's Adjuvant (IFA). Splenocytes from immunized mice were used to generate hybridomas and were screened against LNFPIII conjugates via enzyme-linked immunosorbent assay (ELISA). Three positive hybridomas were expanded, and one hybridoma, producing IgG and IgM antibodies, was cloned via flow cytometry. Clone F1P2H4D8D5 was selected because it produced IgG1 mAbs, but rescreening unexpectedly showed binding to both LNFPIII and lacto-N-neotetraose (LNnT) conjugates. To further assess the specificity of the mAb, we screened it on two glycan microarrays and found no significant binding. This finding suggests that the mAb binds to the acetylphenylenediamine (APD) linker-spacer structure of the conjugate. We present the results herein, suggesting that our new mAb could be a useful probe for conjugates using similar linker spacer structures.
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Despite significant progress, China faces the challenge of re-emerging schistosomiasis transmission in currently controlled areas due, in part, to the presence of a range of animal reservoirs, notably water buffalo and cattle, which can harbor Schistosoma japonicum infections. Environmental, ecological and social-demographic changes in China, shown to affect the distribution of oncomelanid snails, can also impact future schistosomiasis transmission. In light of their importance in the S. japonicum, lifecycle, vaccination has been proposed as a means to reduce the excretion of egg from cattle and buffalo, thereby interrupting transmission from these reservoir hosts to snails. A DNA-based vaccine (SjCTPI) our team developed showed encouraging efficacy against S. japonicum in Chinese water buffaloes. Here we report the results of a double-blind cluster randomized trial aimed at determining the impact of a combination of the SjCTPI bovine vaccine (given as a prime-boost regimen), human mass chemotherapy and snail control on the transmission of S. japonicum in 12 selected administrative villages around the Dongting Lake in Hunan province. The trial confirmed human praziquantel treatment is an effective intervention at the population level. Further, mollusciciding had an indirect ~50% efficacy in reducing human infection rates. Serology showed that the SjCTPI vaccine produced an effective antibody response in vaccinated bovines, resulting in a negative correlation with bovine egg counts observed at all post-vaccination time points. Despite these encouraging outcomes, the effect of the vaccine in preventing human infection was inconclusive. This was likely due to activities undertaken by the China National Schistosomiasis Control Program, notably the treatment, sacrifice or removal of bovines from trial villages, over which we had no control; as a result, the trial design was compromised, reducing power and contaminating outcome measures. This highlights the difficulties in undertaking field trials of this nature and magnitude, particularly over a long period, and emphasizes the importance of mathematical modeling in predicting the potential impact of control intervention measures. A transmission blocking vaccine targeting bovines for the prevention of S. japonicum with the required protective efficacy would be invaluable in tandem with other preventive intervention measures if the goal of eliminating schistosomiasis from China is to become a reality.
Assuntos
Anti-Helmínticos/uso terapêutico , Doenças dos Bovinos/prevenção & controle , Praziquantel/uso terapêutico , Esquistossomose Japônica/prevenção & controle , Vacinação/veterinária , Vacinas/uso terapêutico , Adolescente , Adulto , Idoso , Animais , Búfalos , Bovinos , Criança , Pré-Escolar , China , Método Duplo-Cego , Humanos , Pessoa de Meia-Idade , Esquistossomose Japônica/transmissão , Esquistossomose Japônica/veterinária , Caramujos , Adulto JovemRESUMO
The population of Brazil is currently characterised by many individuals harbouring low-intensity Schistosoma mansoni infections. The Kato-Katz technique is the diagnostic method recommended by the World Health Organization (WHO) to assess these infections, but this method is not sensitive enough in the context of low egg excretion. In this regard, potential alternatives are being employed to overcome the limits of the Kato-Katz technique. In the present review, we evaluated the performance of parasitological and immunological approaches adopted in Brazilian areas. Currently, the diagnostic choices involve a combination of strategies, including the utilisation of antibody methods to screen individuals and then subsequent confirmation of positive cases by intensive parasitological investigations.
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Anticorpos Anti-Helmínticos/análise , Antígenos de Helmintos/análise , Técnicas de Laboratório Clínico/métodos , Fezes/parasitologia , Schistosoma mansoni , Esquistossomose mansoni/diagnóstico , Animais , Brasil/epidemiologia , Doenças Endêmicas , Humanos , Técnicas Imunoenzimáticas , Contagem de Ovos de Parasitas , Schistosoma mansoni/imunologia , Schistosoma mansoni/isolamento & purificação , Esquistossomose mansoni/epidemiologia , Sensibilidade e Especificidade , Índice de Gravidade de DoençaRESUMO
Schistosomiasis remains a serious zoonotic disease in China and the Philippines. Water buffalo and cattle account for the majority of transmission. Vaccination of water buffalo is considered a key strategy to reduce disease prevalence. Previously, we showed that vaccination of water buffalo with SjC23 or SjCTPI plasmid DNA vaccines, induced 50% efficacy to challenge infection. Here, we evaluated several parameters to determine if we can develop a two dose vaccine that maintains the efficacy of the three dose vaccine. We performed four trials evaluating: (1) lab produced vs. GLP grade vaccines, (2) varying the time between prime and boost, (3) the influence of an IL-12 adjuvant, and (4) a two dose heterologous (DNA-protein) prime-boost. We found the source of the DNA vaccines did not matter, nor did increasing the interval between prime and boost. Elimination of the IL-12 plasmid lowered homologous DNA-DNA vaccine efficacy. A major finding was that the heterologous prime boost improved vaccine efficacy, with the prime-boost regimen incorporating both antigens providing a 55% reduction in adult worms and 53% reduction in liver eggs. Vaccinated buffalo produced vaccine-specific antibody responses. These trials suggest that highly effective vaccination against schistosomes can be achieved using a two dose regimen. No adjuvants were used with the protein boost, and the potential that addition of adjuvant to the protein boost to further increase efficacy should be evaluated. These results suggest that use of these two schistosome vaccines can be part of an integrated control strategy to reduce transmission of schistosomiasis in Asia.
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Búfalos/imunologia , Proteínas de Helminto/imunologia , Schistosoma/imunologia , Vacinas de DNA/imunologia , Adjuvantes Imunológicos/administração & dosagem , Animais , Antígenos de Helmintos/imunologia , Búfalos/parasitologia , China , Imunização Secundária/métodos , Interleucina-12/imunologia , Vacinação/métodos , Zoonoses/imunologia , Zoonoses/parasitologia , Zoonoses/prevenção & controleRESUMO
BACKGROUND: Despite decades of use of control programs, schistosomiasis remains a global public health problem. To further reduce prevalence and intensity of infection, or to achieve the goal of elimination in low-endemic areas, there needs to be better diagnostic tools to detect low-intensity infections in low-endemic areas in Brazil. The rationale for development of new diagnostic tools is that the current standard test Kato-Katz (KK) is not sensitive enough to detect low-intensity infections in low-endemic areas. In order to develop new diagnostic tools, we employed a proteomics approach to identify biomarkers associated with schistosome-specific immune responses in hopes of developing sensitive and specific new methods for immunodiagnosis. METHODS AND FINDINGS: Immunoproteomic analyses were performed on egg extracts of Schistosoma mansoni using pooled sera from infected or non-infected individuals from a low-endemic area of Brazil. Cross reactivity with other soil-transmitted helminths (STH) was determined using pooled sera from individuals uniquely infected with different helminths. Using this approach, we identified 23 targets recognized by schistosome acute and chronic sera samples. To identify immunoreactive targets that were likely glycan epitopes, we compared these targets to the immunoreactivity of spots treated with sodium metaperiodate oxidation of egg extract. This treatment yielded 12/23 spots maintaining immunoreactivity, suggesting that they were protein epitopes. From these 12 spots, 11 spots cross-reacted with sera from individuals infected with other STH and 10 spots cross-reacted with the negative control group. Spot number 5 was exclusively immunoreactive with sera from S. mansoni-infected groups in native and deglycosylated conditions and corresponds to Major Egg Antigen (MEA). We expressed MEA as a recombinant protein and showed a similar recognition pattern to that of the native protein via western blot. IgG-ELISA gave a sensitivity of 87.10% and specificity of 89.09% represented by area under the ROC curve of 0.95. IgG-ELISA performed better than the conventional KK (2 slides), identifying 56/64 cases harboring 1-10 eggs per gram of feces that were undiagnosed by KK parasitological technique. CONCLUSIONS: The serological proteome approach was able to identify a new diagnostic candidate. The recombinant egg antigen provided good performance in IgG-ELISA to detect individuals with extreme low-intensity infections (1 egg per gram of feces). Therefore, the IgG-ELISA using this newly identified recombinant MEA can be a useful tool combined with other techniques in low-endemic areas to determine the true prevalence of schistosome infection that is underestimated by the KK method. Further, to overcome the complexity of ELISA in the field, a second generation of antibody-based rapid diagnostic tests (RDT) can be developed.
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Antígenos de Helmintos/sangue , Proteínas de Helminto/sangue , Proteoma/metabolismo , Schistosoma mansoni/imunologia , Esquistossomose mansoni/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Antígenos de Helmintos/imunologia , Biomarcadores/sangue , Brasil , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Fezes/parasitologia , Feminino , Proteínas de Helminto/imunologia , Humanos , Imunoglobulina G/sangue , Lactente , Masculino , Pessoa de Meia-Idade , Óvulo/imunologia , Contagem de Ovos de Parasitas , Proteoma/imunologia , Proteômica , Proteínas Recombinantes/imunologia , Esquistossomose mansoni/sangue , Sensibilidade e Especificidade , Testes Sorológicos/métodosRESUMO
The population of Brazil is currently characterised by many individuals harbouring low-intensity Schistosoma mansoni infections. The Kato-Katz technique is the diagnostic method recommended by the World Health Organization (WHO) to assess these infections, but this method is not sensitive enough in the context of low egg excretion. In this regard, potential alternatives are being employed to overcome the limits of the Kato-Katz technique. In the present review, we evaluated the performance of parasitological and immunological approaches adopted in Brazilian areas. Currently, the diagnostic choices involve a combination of strategies, including the utilisation of antibody methods to screen individuals and then subsequent confirmation of positive cases by intensive parasitological investigations.
Assuntos
Humanos , Schistosoma mansoni , ImunoensaioRESUMO
BACKGROUND: Schistosomiasis in the People's Republic of China (PRC) can be traced back to antiquity. In the past 60 years, the Chinese government has made great efforts to control this persistent disease with elimination slated by 2020 through the implementation of a comprehensive control strategy. This strategy aims to reduce the role of bovines and humans as sources of infection as a pre-requisite for elimination through transmission interruption. The goal of elimination will be achievable only by the implementation of a sustainable surveillance and control system, with sensitive diagnosis a key feature so that the true disease burden is not underestimated. Currently used diagnostics lack the necessary sensitivity to accurately determine the prevalence of Schistosoma japonicum infection in areas with low infection intensities. It is of critical importance to find and treat people and to identify animals with low-level infections if the National Control Programme for China is to achieve schistosomiasis elimination. METHODS: We evaluated a real-time polymerase chain reaction (qPCR) assay using 633 human stool samples collected from five villages in Hunan, Anhui, Hubei, and Jiangxi provinces, and 182 bovine (70 cattle and 112 buffalo) stool samples obtained from four villages in Hunan, Anhui, and Jiangxi provinces in the PRC. All stool samples were subjected to the miracidium hatching test (MHT, a diagnostic procedure used in the National Schistosomiasis Control Programme) and the qPCR assay. Samples positive by MHT were subjected to either the Kato-Katz technique for humans, or the formalin-ethyl acetate sedimentation-digestion (FEA-SD) procedure for bovines, to determine infection intensities. RESULTS: The qPCR assay exhibited a high level of sensitivity in the detection of S. japonicum infections. With both the human and bovine samples, a significantly higher prevalence was determined using the qPCR assay (11.06% humans, 24.73% bovines) than with the MHT (0.93% humans, 7.69% bovines). The animal contamination index (calculated using data obtained with the qPCR technique) for all positive bovines was 27 618 000 eggs per day, indicating a considerable amount of environmental egg contamination that would be underestimated using less sensitive diagnostic procedures. CONCLUSIONS: The qPCR assay we have evaluated will be applicable as a future field diagnostic and surveillance tool in low-transmission zones where schistosomiasis elimination is targeted and for monitoring post-intervention areas to verify that elimination has been maintained.
Assuntos
Doenças dos Bovinos/diagnóstico , Fezes/parasitologia , Schistosoma japonicum/genética , Esquistossomose Japônica/diagnóstico , Esquistossomose Japônica/epidemiologia , Animais , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , China/epidemiologia , Humanos , Contagem de Ovos de Parasitas , Prevalência , Reação em Cadeia da Polimerase em Tempo Real/métodos , Schistosoma japonicum/isolamento & purificação , Esquistossomose Japônica/transmissão , Esquistossomose Japônica/veterináriaRESUMO
Alterations in lipid metabolism play a significant role in the pathogenesis of obesity-associated disorders, and dysregulation of the lipidome across multiple diseases has prompted research to identify novel lipids indicative of disease progression. To address the significant gap in knowledge regarding the effect of age and diet on the blood lipidome, we used shotgun lipidomics with electrospray ionization-mass spectrometry (ESI-MS). We analyzed blood lipid profiles of female C57BL/6 mice following high-fat diet (HFD) and low-fat diet (LFD) consumption for short (6weeks), long (22weeks), and prolonged (36weeks) periods. We examined endocannabinoid levels, plasma esterase activity, liver homeostasis, and indices of glucose tolerance and insulin sensitivity to compare lipid alterations with metabolic dysregulation. Multivariate analysis indicated differences in dietary blood lipid profiles with the most notable differences after 6weeks along with robust alterations due to age. HFD altered phospholipids, fatty acyls, and glycerolipids. Endocannabinoid levels were affected in an age-dependent manner, while HFD increased plasma esterase activity at all time points, with the most pronounced effect at 6weeks. HFD-consumption also altered liver mRNA levels of PPARα, PPARγ, and CD36. These findings indicate an interaction between dietary fat consumption and aging with widespread effects on the lipidome, which may provide a basis for identification of female-specific obesity- and age-related lipid biomarkers.
Assuntos
Envelhecimento/sangue , Dieta Hiperlipídica , Endocanabinoides/sangue , Metabolismo dos Lipídeos , Lipídeos/sangue , Fatores Etários , Envelhecimento/metabolismo , Animais , Gorduras na Dieta/farmacologia , Endocanabinoides/metabolismo , Feminino , Metabolismo dos Lipídeos/efeitos dos fármacos , Lipídeos/análise , Metaboloma/efeitos dos fármacos , Camundongos , Camundongos Endogâmicos C57BLRESUMO
BACKGROUND: A cross-sectional survey was performed in 2012 among 18 rural barangays in Northern Samar, the Philippines in order to determine the prevalence of single and multiple species helminth infections and the underlying risk factors of acquiring one or more parasites. METHODS: A total of 6976 participants who completed a medical questionnaire and provided a stool sample for examination were included in the final analysis. RESULTS: The overall prevalence rates of Schistosoma japonicum, Ascaris lumbricoides, Trichuris trichiura, and hookworm were found to be moderate to high at 28.9%, 36.5%, 61.8%, and 28.4%, respectively. However, the prevalence of harbouring any of the helminths was found to be higher at 75.6%. Significant variation was evident among the predicted barangay-specific random effects for infection with S. japonicum (barangay variance of 0.66, 95% confidence interval 0.31-1.40) and for any helminth infection (barangay variance of 0.63, 95% confidence interval 0.30-1.29). The predictive models showed, with greater than 80% sensitivity and specificity, that low socio-economic status, low levels of education, poor sanitation, proximity to water sources, occupation (i.e., farming and fishing), and male sex were all reliable indicators of infection status. CONCLUSIONS: This study will aid in the targeting of limited resources for national treatment and WASH (water, sanitation, and hygiene) efforts in low- and middle-income countries.
Assuntos
Helmintíase/epidemiologia , Adolescente , Adulto , Animais , Criança , Pré-Escolar , Estudos Transversais , Fezes/parasitologia , Feminino , Helmintíase/parasitologia , Helmintos/genética , Helmintos/isolamento & purificação , Helmintos/fisiologia , Humanos , Higiene , Masculino , Filipinas/epidemiologia , Prevalência , Fatores de Risco , População Rural , Adulto JovemRESUMO
OBJECTIVE: This study assessed the impact of annual versus biennial praziquantel treatment regimens on the prevalence, intensity of infection, and liver fibrosis dynamics of Asiatic schistosomiasis (caused by Schistosoma japonicum) among individuals residing in 18 endemic barangays in Northern Samar, Philippines. METHODS: Five hundred and sixty-five subjects who reported symptoms of gastrointestinal illness and/or were believed to have clinical morbidity based on physical examination were selected for cohort follow-up. RESULTS: The mean prevalence of schistosomiasis was 34% and the mean intensity of infection was 123.1 eggs per gram. Moderate to severe hepatic fibrosis (grade II/III) was demonstrated in approximately 25% of the study population. As expected, a greater reduction in both the prevalence and intensity of infection was documented with two treatment rounds versus one. Overall, hepatic fibrosis (grades I-III) regressed in only 24.3% of those who received a single treatment and in only 19.3% of those who received two doses. The prevalence of grade II-III fibrosis at baseline (25.2%) remained unchanged 2 years after treatment. CONCLUSIONS: These findings suggest that in order to reverse moderate to severe liver fibrosis due to schistosomiasis and improve clinical outcomes, a higher clinical dosage of praziquantel (i.e., 60-80mg/kg) may be required over an extended duration.
Assuntos
Cirrose Hepática/mortalidade , Praziquantel/administração & dosagem , Esquistossomose/tratamento farmacológico , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Esquema de Medicação , Feminino , Humanos , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Cirrose Hepática/patologia , Masculino , Pessoa de Meia-Idade , Morbidade , Filipinas/epidemiologia , Schistosoma japonicum/efeitos dos fármacos , Esquistossomose/epidemiologia , Esquistossomose/mortalidade , Esquistossomose/parasitologia , Adulto JovemRESUMO
OBJECTIVES: We conducted a cross-sectional survey in 2012 among 22 rural barangays in Northern Samar, the Philippines in order to determine the prevalence of single and multiple species helminth infections, their geospatial distribution and underlying risk factors. METHODS: A total of 10,434 individuals who had completed both a medical questionnaire and a stool examination were included in the analysis. Barangay specific prevalence rates were displayed in ArcMap. RESULTS: The prevalence of Trichuris trichiura infection was found to be the highest at 62.4%, followed by Ascaris lumbricoides, hookworm and S. japonicum with the prevalence rates of 40.2%, 31.32%, and 27.1%, respectively. 52.7% of people were infected with at least two parasites and 4.8% with all four parasites. Males aged 10-19 years were the most vulnerable to coinfection infection. Students, fishermen, farmers and housewives were the most vulnerable occupations for co-infection of A. lumbricoides and T. trichiura. Considerable heterogeneity in the spatial distribution was observed for the different parasite species. There was a considerably higher risk of A. lumbricoides and T. trichiura co-infection in villages with no schistosomiasis infection (P<0.0001) regardless of MDA treatment. CONCLUSIONS: A better understanding of the geospatial distribution of multi-parasitism will guide future integrated strategies leading to elimination.
Assuntos
Helmintíase/epidemiologia , Adolescente , Animais , Ascaríase/epidemiologia , Ascaris lumbricoides , Criança , Estudos Transversais , Feminino , Geografia Médica , Infecções por Uncinaria/epidemiologia , Humanos , Masculino , Filipinas/epidemiologia , Prevalência , Medição de Risco , População Rural , Tricuríase/epidemiologia , Adulto JovemRESUMO
Mass drug administration utilising a single oral dose of 40mg/kg of praziquantel (PZQ) has been endorsed and advocated by the World Health Organisation (WHO) for the global control and elimination of schistosomiasis. However, this strategy is failing primarily because the drugs are not getting to the people who need them the most. The current global coverage is 20%, the drug compliance rate is less than 50%, and the drug efficacy is approximately 50%. Thus in reality, only about 5% of the reservoir human population is actually receiving intermittent chemotherapy. Despite claims that more of the drug will soon be made available the current strategy is inherently flawed and will not lead to disease elimination. We discuss the many practical issues related to this global strategy, and advocate for an integrated control strategy targeting the life cycle and the most at-risk. Moreover, we discuss how an integrated control package for schistosomiasis should fit within a larger integrated health package for rural and remote villages in the developing world. A holistic health system approach is required to achieve sustainable control and ultimately disease elimination.