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1.
PLoS Pathog ; 20(3): e1011879, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38437239

RESUMO

Placental accumulation of Plasmodium falciparum infected erythrocytes results in maternal anemia, low birth weight, and pregnancy loss. The parasite protein VAR2CSA facilitates the accumulation of infected erythrocytes in the placenta through interaction with the host receptor chondroitin sulfate A (CSA). Antibodies that prevent the VAR2CSA-CSA interaction correlate with protection from placental malaria, and VAR2CSA is a high-priority placental malaria vaccine antigen. Here, structure-guided design leveraging the full-length structures of VAR2CSA produced a stable immunogen that retains the critical conserved functional elements of VAR2CSA. The design expressed with a six-fold greater yield than the full-length protein and elicited antibodies that prevent adhesion of infected erythrocytes to CSA. The reduced size and adaptability of the designed immunogen enable efficient production of multiple variants of VAR2CSA for use in a cocktail vaccination strategy to increase the breadth of protection. These designs form strong foundations for the development of potent broadly protective placental malaria vaccines.


Assuntos
Vacinas Antimaláricas , Malária Falciparum , Malária , Humanos , Gravidez , Feminino , Placenta/metabolismo , Malária Falciparum/parasitologia , Anticorpos Antiprotozoários , Plasmodium falciparum/metabolismo , Antígenos de Protozoários , Sulfatos de Condroitina/metabolismo , Eritrócitos/parasitologia
2.
Parasitol Res ; 123(3): 169, 2024 Mar 23.
Artigo em Inglês | MEDLINE | ID: mdl-38520500

RESUMO

Toxoplasmosis, caused by the protozoan parasite Toxoplasma gondii, is a globally distributed zoonotic infection with significant implications for human and animal health. This study investigated the prevalence of T. gondii infection in a population of beef cattle at three different stages of their productive lifespan and examined the impact of T. gondii serological status on blood parameters. A commercial beef fattening unit in Italy was the setting for this research, which involved a biosecurity assessment upon cattle arrival, blood sampling at three time points and Toxoplasma-specific serological testing using indirect fluorescent antibody tests (IFAT). Results revealed a dynamic pattern of T. gondii seropositivity in cattle, with an initial prevalence of 30.6% at arrival (T0) that increased to 44.6% at 14 days (T1) and then decreased slightly to 39.3% at slaughter after 5 months (T2). Interestingly, seroconversion was observed during the study, indicating ongoing infections, and antibody waning occurred in some animals. In terms of blood parameters, seropositive cattle exhibited significantly lower mean corpuscular volume (MCV) and a higher neutrophil-lymphocyte (N/L) ratio, suggesting an activation of the innate immune response. Furthermore, cattle with higher antibody titres displayed higher neutrophil counts. However, all blood parameters with a statistical significance were within the reference range. This study provides for the first time a longitudinal investigation on the serological status for T. gondii in naturally exposed beef cattle. These findings provide valuable insights into the clinico-pathological aspects of natural T. gondii exposure in cattle and underscore the importance of monitoring and managing T. gondii infection in livestock production systems.


Assuntos
Doenças dos Bovinos , Toxoplasma , Toxoplasmose Animal , Bovinos , Animais , Humanos , Toxoplasmose Animal/parasitologia , Estudos Longitudinais , Anticorpos Antiprotozoários , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/parasitologia , Estudos Soroepidemiológicos
3.
Trop Anim Health Prod ; 56(3): 106, 2024 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-38507146

RESUMO

Coxiella burnetii, or Q fever agent, has notable implications for human and livestock health. Infections in cattle primarily manifest through reproductive issues where infected animals shed the bacterium in birth fluids, placental tissues, and milk, serving as potential sources of transmission. Bovine herds become reservoirs, contributing to the environmental contamination of farming areas. Comprehensive studies on the prevalence, transmission routes, and associated risk factors among cattle contribute to the development of effective control strategies, ultimately safeguarding both livestock and public health.Here we determine the prevalence of Coxiella burnetii antibodies against in dairy cattle farms from Kabylia (northern Algeria) and identify the associated risk factors. Bulk tank milk samples from 184 farms were analyzed by indirect ELISA technique, 49 of them were tested positive which corresponds to a prevalence rate of 26.63% (95% CI 20.25-33.01%). Multivariate analysis by logistic regression showed that the risk factors associated with detection of anti-Coxiella burnetii antibodies are: cohabitation of cattle with small ruminants(OR = 3.74 95% CI [1.41-8.92]), exposure to prevailing winds (OR = 5.12 95% CI [2.11-13.45]), and the veterinarian visits frequency(OR = 5.67 95% CI [2.55-13.60]). These findings underscore the susceptibility of dairy cattle to Q fever in the Kabylia region, highlighting practices that pose risks. We recommend the implementation of hygienic measures and adherence to proper farming conditions to mitigate the transmission of Q fever and reduce the associated zoonotic risk.


Assuntos
Doenças dos Bovinos , Coxiella burnetii , Febre Q , Humanos , Bovinos , Animais , Feminino , Gravidez , Febre Q/epidemiologia , Febre Q/veterinária , Febre Q/microbiologia , Leite/microbiologia , Prevalência , Argélia/epidemiologia , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/microbiologia , Placenta , Anticorpos Antibacterianos , Fatores de Risco , Anticorpos Antiprotozoários
4.
PLoS One ; 19(2): e0298393, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38319921

RESUMO

Ocular toxoplasmosis (OT) is caused by protozoan T. gondii. Ophthalmological examination is considered the gold standard for OT diagnosis, and laboratory tests are used for diagnostic confirmation. However, these tests can present different results, which change depending on their basis, on sample type and on patients' clinical alteration. Thus, the aim of the present study is to assess immunodiagnostic and molecular techniques applied in blood, serum and tear fluid to diagnose T. gondii infection in patients seen at an Ophthalmology Clinic. In total, 160 patients were included in the study, 40 of them had OT with active lesions (G1); 40 had OT with healed lesions (G2), 40 had non-toxoplasmic uveitis (G3) and 40 had no ocular alterations (G4). Serum samples were subjected to Immunoenzymatic Assay (ELISA) and to Indirect Immunofluorescence Reaction (IFAT) to search for anti-T. gondii IgM and IgG. Tear fluid samples were analyzed through ELISA for IgA research. All blood and tear fluid samples were subjected to conventional polymerase chain reaction (cPCR) and in a Nested PCR model for T. gondii DNA amplification with targets B1, GRA7 and REP 529. IgG and IgM anti-T. gondii was detected in serum samples from 106 and 15 patients, respectively, when combining ELISA and IFAT results. Anti-T.gondii IgA antibodies were detected in 9.2% of the tear material. Nested PCR with GRA7 target showed higher positivity in blood samples (24.4%); Nested PCR with B1 target showed a higher frequency of positivity in tears (15%). Biological samples of patients with active lesions showed the highest positivity frequencies in all immunodiagnostic assays, as well as in most PCR models. The present results highlighted the need of associating techniques with different fundamentals to confirm OT diagnosis. Furthermore, further tear fluid analyses should be performed to validate this biological material as lesser invasive alternative for the more accurate OT diagnosis.


Assuntos
Toxoplasma , Toxoplasmose Ocular , Humanos , Brasil , Anticorpos Antiprotozoários , Testes Imunológicos , Imunoglobulina G , Imunoglobulina M , Imunoglobulina A/análise
5.
Sci Rep ; 14(1): 4888, 2024 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-38418831

RESUMO

Clinical immunity to malaria develops slowly after repeated episodes of infection and antibodies are essential in naturally acquired immunity against malaria. However, chronic exposure to malaria has been linked to perturbation in B-cell homeostasis with the accumulation of atypical memory B cells. It is unclear how perturbations in B cell subsets influence antibody breadth, avidity, and function in individuals naturally exposed to malaria. We show that individuals living in high malaria transmission regions in Ghana have higher Plasmodium falciparum merozoite antigen-specific antibodies and an increased antibody breadth score but lower antibody avidities relative to low transmission regions. The frequency of circulating atypical memory B cells is positively associated with an individual's antibody breadth. In vitro growth inhibition is independent of the ability to bind to free merozoites but associated with the breadth of antibody reactivity in an individual. Taken together, our data shows that repeated malaria episodes hamper the development of high avid antibodies which is compensated for by an increase in antibody breadth. Our results provide evidence to reinforce the idea that in regions with high malaria prevalence, repeated malaria infections lead to the broadening of antibody diversity and the continued presence of atypical memory B cell populations.


Assuntos
Malária Falciparum , Malária , Adulto , Animais , Humanos , Malária Falciparum/epidemiologia , Células B de Memória , Antígenos de Protozoários , Anticorpos Antiprotozoários , Plasmodium falciparum , Merozoítos , Proteínas de Protozoários
6.
Parasite Immunol ; 46(2): e13023, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38372452

RESUMO

Toxoplasmosis is one of the most dangerous zoonotic diseases, causing serious economic losses worldwide due to abortion and reproductive problems. Vaccination is the best way to prevent disease; thus, it is imperative to develop a candidate vaccine for toxoplasmosis. BAG1 and ROP8 have the potential to become vaccine candidates. In this study, rTgBAG1, rTgROP8, and rTgBAG1-rTgROP8 were used to evaluate the immune effect of vaccines in each group by detecting the humoral and cellular immune response levels of BABL/c mice after immunization and the ability to resist acute and chronic infection with Toxoplasma gondii (T. gondii). We divided the mice into vaccine groups with different proteins, and the mice were immunized on days 0, 14, and 28. The protective effects of different proteins against T. gondii were analysed by measuring the cytokines, serum antibodies, splenocyte proliferation assay results, survival time, and number and diameter of brain cysts of mice after infection. The vaccine groups exhibited substantially higher IgG, IgG1, and IgG2a levels and effectively stimulated lymphocyte proliferation. The levels of IFN-γ and IL-2 in the vaccine group were significantly increased. The survival time of the mice in each vaccine group was prolonged and the diameter of the cysts in the vaccine group was smaller; rTgBAG1-rTgROP8 had a better protection. Our study showed that the rTgBAG1, rTgROP8, and rTgBAG1-rTgROP8 recombinant protein vaccines are partial but effective approaches against acute or chronic T. gondii infection. They are potential candidates for a toxoplasmosis vaccine.


Assuntos
Vacinas Protozoárias , Toxoplasmose , Animais , Camundongos , Anticorpos Antiprotozoários , Antígenos de Protozoários/genética , Imunidade Celular , Imunização , Imunoglobulina G , Camundongos Endogâmicos BALB C , Proteínas de Protozoários , Vacinas Protozoárias/imunologia , Proteínas Recombinantes/genética , Toxoplasma , Toxoplasmose/prevenção & controle , Vacinação
7.
Sci Rep ; 14(1): 2812, 2024 02 02.
Artigo em Inglês | MEDLINE | ID: mdl-38307906

RESUMO

Predators in food webs are valuable sentinel species for zoonotic and multi-host pathogens such as Toxoplasma gondii. This protozoan parasite is ubiquitous in warm-blooded vertebrates, and can have serious adverse effects in immunocompromised hosts and foetuses. In northern ecosystems, T. gondii is disproportionately prevalent in Inuit people and wildlife, in part due to multiple routes of transmission. We combined data on T. gondii infection in foxes from Nunavik (northern Québec, Canada) with stable isotope data tracking trophic relationships between foxes and several of their main prey species. Red (Vulpes vulpes) and Arctic fox (Vulpes lagopus) carcasses were collected by local trappers from 2015 to 2019. We used magnetic capture PCR to detect DNA of T. gondii in heart and brain tissues, and enzyme-linked immunosorbent assay to detect antibodies in blood. By linking infection status with diet composition, we showed that infected foxes had a higher probability of consuming aquatic prey and migratory geese, suggesting that these may be important sources of T. gondii transmission in the Arctic. This use of stable isotopes to reveal parasite transmission pathways can be applied more broadly to other foodborne pathogens, and provides evidence to assess and mitigate potential human and animal health risks associated with T. gondii in northern ecosystems.


Assuntos
Raposas , Toxoplasma , Toxoplasmose Animal , Animais , Animais Selvagens/parasitologia , Anticorpos Antiprotozoários , Ecossistema , Raposas/parasitologia , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/transmissão , Dieta/veterinária
8.
Front Public Health ; 12: 1340434, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38333736

RESUMO

Introduction: Despite human toxoplasmosis and toxocariasis having been listed among the top six most neglected parasitic zoonoses worldwide, presenting similar associated risk factors and transmission routes, few studies have been conducted in pregnant women and the consequences of concurrent infection remain to be fully established. Accordingly, the present study has serologically assessed the co-infection and associated risk factors for Toxoplasma gondii and Toxocara spp. in pregnant women, assisted by the public Unified National Health System (SUS) in southeastern Brazil. Materials and Methods: Blood samples were collected and tested for IgG antibodies against Toxoplasma gondii by chemiluminescence immunoassay and against Toxocara spp. by enzyme-linked immunosorbent assay (ELISA). An epidemiological questionnaire was applied to gather socioeconomic information to assess the risk factors associated with seropositivity to toxocariasis/toxoplasmosis by univariate analysis followed by logistic regression. Results: Overall, seropositivity was 69/280 (24.6, 95% CI: 19.96-30.01) for T. gondii and 56/280 (20.0, 95% CI: 15.73-25.08) for Toxocara spp. Co-infection was observed in 25/280 (8.9, 95% CI: 6.12-12.85) pregnant women, with increased odds (OR: 3.3, CI 95%: 1.77-6.14, p = 0.0002). Logistic regression revealed that a higher educational level (high school or college) significantly reduced the likelihood of co-infection seropositivity, owning cats increased the odds of toxocariasis, and older pregnant women presented significantly higher T. gondii seropositivity. Conclusion: Co-infection herein highlights the importance of educational programs in the prevention of toxocariasis and toxoplasmosis in pregnant women and other high-risk populations.


Assuntos
Coinfecção , Toxocaríase , Toxoplasma , Toxoplasmose , Animais , Humanos , Feminino , Gravidez , Toxocaríase/epidemiologia , Toxocara , Gestantes , Brasil/epidemiologia , Coinfecção/epidemiologia , Anticorpos Antiprotozoários , Toxoplasmose/epidemiologia
9.
Parasite ; 31: 7, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38334687

RESUMO

The ISAGA immunocapture test for the detection of anti-Toxoplasma immunoglobulin M is a manual technique known for its excellent sensitivity and specificity. The purpose of this retrospective, multicenter study was to compare the performances and agreement between ISAGA and other IgM detection techniques before cessation of ISAGA production. The analytic performance of the different tests was evaluated using 1,341 serum samples from adults with positive IgM and negative IgG to Toxoplasma gondii, and 1,206 sera from neonates born to mothers with seroconversion. The agreement between the tests was evaluated on 13,506 adult and 5,795 child serum samples. The sensitivity of Toxo-ISAGA IgM® (adults 98.7%, neonates 63.1%) was similar to that of Platelia Toxo IgM® (adults 94.4%, neonates 64.6%), and significantly higher than Liaison Toxo IgM® (adults 90.6%), Architect/Alinity Toxo IgM® (adults 95.7%, neonates 48.6%), and Vidas Toxo IgM® (adults 81.8%, neonates 17.5%). However, the specificities varied between 24.4% (Platelia Toxo IgM®) and 95.2% (Liaison Toxo IgM®) in adults and were >95% for all tests in neonates. An analysis of the kappa coefficients showed better agreement between ISAGA IgM® and the other tests in children (0.75-0.83%) than in adults (0.11-0.53%). We conclude that, in the absence of Toxo-ISAGA IgM®, the association of a very sensitive technique (Platelia Toxo IgM® or Architect/Alinity Toxo IgM®) and a very specific technique (Vidas Toxo IgM® or Liaison Toxo IgM®) is recommended for IgM detection in adult sera. For neonates, Platelia Toxo IgM® appeared to be the best alternative to replace Toxo-ISAGA IgM®.


Title: Performances comparatives des tests ISAGA IgM et ELISA pour le diagnostic des infections maternelles et congénitales à Toxoplasma : quelle technique pourrait remplacer ISAGA IgM ? Abstract: Le test d'immunocapture ISAGA pour la détection des immunoglobulines M anti-Toxoplasma est une technique manuelle connue pour son excellente sensibilité et spécificité. Le but de cette étude rétrospective et multicentrique était de comparer les performances et la concordance entre l'ISAGA et d'autres techniques de détection d'IgM avant l'arrêt de la commercialisation de l'ISAGA. Les performances analytiques des différents tests ont été évaluées à partir de 1 341 échantillons de sérum d'adultes présentant des IgM positives et des IgG négatives à Toxoplasma gondii, et de 1 206 sérums de nouveau-nés nés de mères présentant une séroconversion. La concordance entre les tests a été évaluée sur 13 506 échantillons de sérum d'adultes et 5 795 sérums d'enfants. La sensibilité de Toxo-ISAGA IgM® (adultes 98,7 %, nouveau-nés 63,1 %) était similaire à celle de Platelia Toxo IgM® (adultes 94,4 %, nouveau-nés 64,6 %) et significativement supérieure à celle de Liaison Toxo IgM® (adultes 90,6 %), Architect/Alinity Toxo IgM® (adultes 95,7 %, nouveau-nés 48,6 %) et Vidas Toxo IgM® (adultes 81,8 %, nouveau-nés 17,5 %). Cependant, les spécificités variaient entre 24,4 % (Platelia Toxo IgM®) et 95,2 % (Liaison Toxo IgM®) chez les adultes et étaient >95 % pour tous les tests chez les nouveau-nés. L'analyse des coefficients kappa a montré une meilleure concordance entre ISAGA IgM® et les autres tests chez les enfants (0,75­0,83%) que chez les adultes (0,11­0,53%). Nous concluons qu'en l'absence de Toxo-ISAGA IgM®, l'association d'une technique très sensible (Platelia Toxo IgM® ou Architect/Alinity Toxo IgM®) et d'une technique très spécifique (Vidas Toxo IgM® ou Liaison Toxo IgM®) est recommandée pour la détection des IgM dans les sérums adultes. Pour les nouveau-nés, Platelia Toxo IgM® apparaît comme la meilleure alternative en remplacement de Toxo-ISAGA IgM®.


Assuntos
Toxoplasma , Toxoplasmose Congênita , Toxoplasmose , Criança , Adulto , Feminino , Recém-Nascido , Humanos , Toxoplasmose Congênita/diagnóstico , Toxoplasmose/diagnóstico , Estudos Retrospectivos , Imunoglobulina M , Ensaio de Imunoadsorção Enzimática , Anticorpos Antiprotozoários
10.
Vaccine ; 42(7): 1785-1792, 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38365484

RESUMO

Plasmodium vivax malaria is increasingly recognized as a major global health problem and the socio-economic impact of P.vivax-induced burden is huge. Vaccine development against P. vivax malaria has been hampered by the lack of an in vitro culture system and poor access to P. vivax sporozoites. The recent generation of Plasmodium falciparum parasites that express a functional P. vivax AMA1 molecule has provided a platform for in vitro evaluation of PvAMA1 as a potential blood stage vaccine. Three so-called PvAMA1 Diversity Covering (DiCo) proteins were designed to assess their potential to induce a functional and broad humoral immune response to the polymorphic PvAMA1 molecule. Rabbits were immunized with the mixture of three, Pichia-produced, PvAMA1 DiCo proteins, as well as with 2 naturally occurring PvAMA1 alleles. For these three groups, the experimental adjuvant raffinose fatty acid sulfate ester (RFASE) was used, while in a fourth group the purified main mono-esterified constituent (RSL10) of this adjuvant was used. Animals immunized with the mixture of the three PvAMA1 DiCo proteins in RFASE showed high anti-PvAMA1 antibody titers against three naturally occurring PvAMA1variants while also high growth-inhibitory capacity was observed against P. falciparum parasites expressing PvAMA1. This supports further clinical development of the PvAMA1 DiCo mixture as a potential malaria vaccine. However, as the single allele PvAMA1 SalI-group showed similar characteristics in antibody titer and inhibition levels as the PvAMA1 DiCo mixture-group, this raises the question whether a mixture is really necessary to overcome the polymorphism in the vaccine candidate. RFASE induced strong humoral responses, as did the animals immunized with the purified component, RSL10. This suggests that RSL10 is the active ingredient. However, one of the RSL10-immunized animal showed a delayed response, necessitating further research into the clinical development of RSL10.


Assuntos
Vacinas Antimaláricas , Malária Falciparum , Malária Vivax , Parasitos , Animais , Coelhos , Proteínas de Protozoários/genética , Plasmodium vivax , Rafinose , Sulfatos , Proteínas de Membrana/genética , Antígenos de Protozoários/genética , Adjuvantes Imunológicos , Malária Falciparum/prevenção & controle , Plasmodium falciparum , Malária Vivax/prevenção & controle , Anticorpos Antiprotozoários
11.
Vaccine ; 42(8): 1980-1992, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38388238

RESUMO

Two malaria transmission-blocking vaccine (TBV) candidates, R0.6C and ProC6C, have completed preclinical development including the selection of adjuvants, Alhydrogel® with or without the saponin based adjuvant Matrix-M™. Here, we report on the final drug product (formulation) design of R0.6C and ProC6C and evaluate their safety and biochemical stability in preparation for preclinical and clinical pharmacy handling. The point-of-injection stability studies demonstrated that both the R0.6C and ProC6C antigens are stable on Alhydrogel in the presence or absence of Matrix-M for up to 24 h at room temperature. As this is the first study to combine Alhydrogel and Matrix-M for clinical use, we also evaluated their potential interactions. Matrix-M adsorbs to Alhydrogel, while not displacing the > 95 % adsorbed protein. The R0.6C and ProC6C formulations were found to be safe and well tolerated in repeated dose toxicity studies in rabbits generating high levels of functional antibodies that blocked infection of mosquitoes. Further, the R0.6C and ProC6C drug products were found to be stable for minimally 24 months when stored at 2-8 °C, with studies ongoing through 36 months. Together, this data demonstrates the safety and suitability of the L. lactis expression system as well as supports the clinical testing of the R0.6C and ProC6C malaria vaccine candidates in First-In-Human clinical trials.


Assuntos
Vacinas Antimaláricas , Malária Falciparum , Animais , Coelhos , Hidróxido de Alumínio , Anticorpos Antiprotozoários , Antígenos de Protozoários , Vacinas Antimaláricas/efeitos adversos , Malária Falciparum/prevenção & controle , Plasmodium falciparum , Proteínas de Protozoários
12.
BMC Vet Res ; 20(1): 62, 2024 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-38389083

RESUMO

BACKGROUND: The wild boar (Sus scrofa) and the Apennine wolf (Canis lupus italicus) are two wild species that have both increased their presence in the Italian territory, albeit in varying numbers. They can be occasionally found in peri-urban areas as well. Both of these species can serve as intermediate hosts for Toxoplasma gondii, as they can become infected either through the consumption of oocysts found in water, soil, or on vegetables, or through the ingestion of meat containing bradyzoites. Consequently, these animals can be regarded as key indicators of Toxoplasma presence in the wild or peri-urban environment. In our study, we examined a total of 174 wild boar meat juice and 128 wolf sera from Italy for the detection of T. gondii IgG using the indirect fluorescent antibody test (IFAT). RESULTS: The results showed that 40 (22.6%) of the wild boar meat juice and 34 (26.6%) of the wolf serum samples tested positive. Interestingly, there were no significant differences in seropositivity with respect to gender, age group, or the region of origin in both species. CONCLUSIONS: Overall the results indicate a moderate exposure in both the species under investigation, highlighting the spread of T. gondii in sylvatic and periurban environments. The prevalence of T. gondii in wild boar is consistent with findings from other studies conducted in Europe. Our study, with a considerably larger sample size compared to the available research in European context, provides valuable data on the seroprevalence of T. gondii in wolves.


Assuntos
Doenças dos Suínos , Toxoplasma , Toxoplasmose Animal , Lobos , Suínos , Animais , Estudos Soroepidemiológicos , Toxoplasmose Animal/epidemiologia , Doenças dos Suínos/epidemiologia , Itália/epidemiologia , Sus scrofa , Anticorpos Antiprotozoários
13.
BMC Vet Res ; 20(1): 71, 2024 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-38395812

RESUMO

Toxoplasma gondii causes lifelong infection in most definitive and intermediate hosts. Clinical cases of toxoplasmosis in captive cheetahs have been reported. However, there are few reports of viable T. gondii strains isolated from cheetahs. Here, T. gondii infection was investigated using molecular and serological assays in cheetahs from China. Modified agglutination test (MAT) (cut-off: 1:25) indicated that all six examined cheetahs (n = 6) showed T. gondii antibodies. Toxoplasma gondii DNA was detected in three out of five cheetahs. Two viable T. gondii strains were isolated from the striated muscles of two cheetahs using mice bioassay. They were designated as TgCheetahCHn1 and TgCheetahCHn2. Genetic characterization of DNA derived from tachyzoites was performed using RFLP-PCR of 10 markers. Toxoplasma gondii TgCheetahCHn1 is ToxoDB PCR-RFLP genotype #319, and the alleles of ROP18/ROP5 types were 3/7. TgCheetahCHn2 is ToxoDB genotype #9, and the alleles of ROP18/ROP5 were 3/6. The average survival time of TgCheetahCHn1-infected Swiss mice was 22 ± 1 days (n = 23), and the mice did not have detectable T. gondii-specific antibodies until 117 ± 30 days post-inoculation (n = 8), therefore, TgCheetahCHn1 had intermediate virulence. TgCheetahCHn2 was avirulent for Swiss mice. Few brain tissue cysts (0-50) were observed in the mice inoculated with TgCheetahCHn1 or TgCheetahCHn2. The results provide direct evidence of cheetah as intermediate host of T. gondii.


Assuntos
Acinonyx , Doenças dos Roedores , Toxoplasma , Toxoplasmose Animal , Animais , Camundongos , Genótipo , Anticorpos Antiprotozoários , DNA de Protozoário/genética
14.
Vaccine ; 42(6): 1342-1351, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38310017

RESUMO

Toxoplasma gondii (T. gondii) is one of the most common pathogenic protozoa in the world, and causes toxoplasmosis, which in varying degrees causes significant economic losses and poses a serious public health challenge globally. To date, the development of an effective vaccine for human toxoplasmosis remains a challenge. Given that T.gondii calcium-dependent protein kinase 3 (CDPK3), dense granule protein 35 (GRA35) and rhoptry organelle protein 46 (ROP46) play key roles during Toxoplasma gondii invasion of host cells, we developed a protein vaccine cocktail including these proteins and validated its protective efficacy. The specific protective effects of vaccine on mice were analyzed by measuring serum antibodies, cytokines, splenocyte proliferation, the percentage of CD4+ and CD8+ T-lymphocytes, survival rate, and parasite cyst burden. The results showed that mice vaccinated with a three-protein cocktail produced the highest levels of immune protein antibodies to IgG, and high levels of IFN-γ, IL-2, IL-4, and IL-10 compared to other mice vaccinated with two proteins. In addition, CD4+ and CD8+ T cell percentages were significantly elevated. Compared to the control groups, mice vaccinated with the three-protein cocktail survived significantly longer after acute infection with T. gondii and had significantly fewer cysts after chronic infection. These results demonstrated that a cocktail vaccine of TgCDPK3, TgGRA35, and TgROP46 can effectively induce cellular and humoral immune responses with good protective effects in mice, indicating its potential as vaccine candidates for toxoplasmosis.


Assuntos
Proteínas Quinases , Vacinas Protozoárias , Toxoplasma , Toxoplasmose Animal , Toxoplasmose , Vacinas de DNA , Animais , Camundongos , Humanos , Camundongos Endogâmicos BALB C , Toxoplasmose/prevenção & controle , Proteínas de Protozoários/genética , Organelas , Anticorpos Antiprotozoários , Toxoplasmose Animal/prevenção & controle
15.
Cytokine ; 177: 156545, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38368695

RESUMO

The symptomatology of COVID-19 is dependent on the immune status and the cytokine response of the host. The cytokine level of the host is influenced by the presence of chronic persistent or latent infections with co-pathogens. Parasitic diseases are known to induce host immune-modulation which may impact the response to co-infection. Toxoplasmosis is a widespread protozoal infection that remains quiescent in its latent form to be re-activated during states of immune depression. Clinical data on the relation between toxoplasmosis and COVID-19 cytokine profile and symptomatology are still insufficient. Seventy-nine subjects were included in this study. Patients were diagnosed with COVID-19 by PCR. Serological testing for toxoplasmosis was performed by the detection of anti-Toxoplasma IgG antibodies, in addition to IgG avidity testing. IFN-γ and TNF-α levels were determined by RT-PCR. Among patients diagnosed with COVID-19, 67.1% were seronegative for anti-Toxoplasma IgG, while 32.9% were seropositive. High avidity was found in 10 cases (40% of seropositive cases), 4 of whom required ICU administration, while low avidity was found in 15 cases (60%), 7 of which were administered to the ICU. TNF-α and INF-γ levels were significantly higher in COVID-19 patients than in healthy control subjects. No significant association was found between the seroprevalence of toxoplasmosis and the presence of COVID-19 and its severity. Cytokines were significantly higher in both seropositive and seronegative COVID-19 patients than in their control counterparts. The high prevalence of toxoplasmosis merits further exploration of its relation to COVID-19 by mass studies.


Assuntos
COVID-19 , Coinfecção , Toxoplasma , Toxoplasmose , Humanos , Fator de Necrose Tumoral alfa , SARS-CoV-2 , Estudos Soroepidemiológicos , Imunoglobulina G , Citocinas , Imunoglobulina M , Anticorpos Antiprotozoários , Gravidade do Paciente
16.
PLoS One ; 19(2): e0298357, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38377066

RESUMO

Toxoplasma gondii and Trichinella spp. are critical tissue-dwelling foodborne zoonotic parasites associated with pork consumption and pig rearing. Despite being a major pig-rearing region in the country, Northeastern India has not undergone any investigation regarding the presence of T. gondii and Trichinella spp. in pigs. Therefore, this study aims to determine the seroprevalence of T. gondii and Trichinella spp. and identify associated risk factors in pigs reared by tribal communities and small-holder livestock farmers in the northeastern region of India. In a cross-sectional serological survey, 400 pigs from 400 households across five northeastern states of India underwent testing for the seroprevalence of porcine toxoplasmosis and trichinellosis. Serum samples (80 from each state) were analyzed using commercially available ELISA assays. Data on backyard farm characteristics and various management aspects were collected, and risk factors linked with prevalence were analyzed through univariate and multivariate logistic regression analysis. The findings revealed that the apparent and true prevalence of anti-T. gondii antibodies were 45% (40.12-49.88, 95% CI) and 45.7% (40.7-50.69, 95% CI), respectively. As for anti- Trichinella antibodies, both the apparent and true prevalence were 0.75% (-0.1-1.6, 95% CI). The univariate and multivariate analyses indicated that age above 24 months (OR 7.20, 95% CI 2.45-23.71), exposure to cats (OR = 5.87, 95% CI 2.55-14.05), and farms operating for breeding purposes (OR = 5.60, 95% CI 3.01-11.04) were significant risk factors associated with the seroprevalence of T. gondii. This study marks the initial documentation of the seroprevalence of T. gondii and Trichinella spp. in pigs reared by tribal communities in Northeastern India. The results emphasize the significance of these parasites as foodborne zoonotic threats in the region, potentially posing substantial public health risks, especially within tribal and rural communities. The insights derived from this research could be valuable in formulating targeted preventive and control strategies against T. gondii and Trichinella spp. in pigs, not only in this region but also in areas with similar rearing practices.


Assuntos
Doenças dos Suínos , Toxoplasma , Toxoplasmose Animal , Trichinella , Suínos , Animais , Humanos , Gado , Estudos Soroepidemiológicos , Fazendeiros , Estudos Transversais , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/parasitologia , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/parasitologia , Anticorpos Antiprotozoários
17.
J Infect Dev Ctries ; 18(1): 60-65, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38377086

RESUMO

INTRODUCTION: Toxoplasma gondii is an obligate intracellular parasite affecting a broad range of warm-blooded animals, including humans. Infection acquired during pregnancy can be transmitted to the fetus and leading to serious problems such as spontaneous abortion, stillbirth, or severe mental and/or physical handicaps in the child. The purpose of this study was to investigate the seroprevalence of Toxoplasma infection and related risk factors in pregnant woman. METHODOLOGY: The study enrolled 1200 serum samples of pregnant women from February-November 2017. Then the samples were tested for the presence of anti-T. gondii antibodies (Ab) using enzyme-linked immunosorbent assay. RESULTS: Out of the 1200 samples, 381 (31.7%) and 41 (3.4%) subjects were positive for IgG and IgM Ab, respectively. Among the evaluated risk factors, the seroprevalence of Toxoplasma infection was not related to the occupation in a significant way. However significant relationship was observed with factors such as; contact with soil, cats, consumption of raw washed vegetables, and washed hands before meals. CONCLUSIONS: According to the results, more than two-thirds of pregnant women are susceptible to Toxoplasma infection, hence training health care programs should be provided to prevent infection.


Assuntos
Aborto Espontâneo , Toxoplasma , Toxoplasmose , Animais , Criança , Humanos , Feminino , Gravidez , Gestantes , Estudos Soroepidemiológicos , Anticorpos Antiprotozoários , Imunoglobulina G , Estudos Transversais , Toxoplasmose/epidemiologia , Fatores de Risco , Imunoglobulina M
18.
PLoS One ; 19(2): e0297523, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38394236

RESUMO

BACKGROUND: Schizophrenia, a complex neuropsychiatric disorder, is believed to be influenced by various factors including environmental exposures. A potential environmental factor is the infection by the obligate intracellular parasitic protozoan, Toxoplasma gondii which affects neurotransmitter levels, which could potentially exacerbate, trigger symptoms of schizophrenia or make them worst. OBJECTIVE: To investigate the association between Toxoplasma gondii seropositivity and psychopathological presentation in persons with schizophrenia in Ecuador. METHODS: This study was conducted at the Neuroscience Institute of Guayaquil, Ecuador. Among 368 inpatients, 104 were selected based on specific inclusion and exclusion criteria. Descriptive statistics captured patient characteristics and mental health outcomes. Logistic regression models estimated the effect of toxoplasmosis on various mental health outcomes, controlling for demographic and health-related variables. RESULTS: 86.5% of participants were seropositive for toxoplasmosis. Toxoplasma-seropositive schizophrenic patients had a lower risk of depression but a significantly higher risk of disorientation. The most prevalent mental health outcomes were Language Impairments (70.2%) and Bizarre Behavior (76.0%). CONCLUSION: Our findings suggest that Toxoplasma gondii seropositivity may have specific effects on mental functions in schizophrenic patients, particularly reducing the risk of depression but increasing the risk of disorientation. Further studies are required to clarify these associations and the potential underlying mechanisms.


Assuntos
Esquizofrenia , Toxoplasma , Toxoplasmose , Humanos , Equador/epidemiologia , Anticorpos Antiprotozoários , Toxoplasmose/complicações , Toxoplasmose/epidemiologia , Esquizofrenia/complicações , Esquizofrenia/epidemiologia , Esquizofrenia/parasitologia , Confusão , Fatores de Risco , Estudos Soroepidemiológicos
19.
Methods Mol Biol ; 2762: 109-121, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38315362

RESUMO

Malaria is a vector-borne disease caused by Plasmodium parasites of which Plasmodium falciparum contributed to an estimated 247 million cases worldwide in 2021 (WHO malaria report 2022). The P. falciparum Circumsporozoite protein (PfCSP) covers the surface of the sporozoite which is critical to cell invasion in the human host. PfCSP is the leading pre-erythrocytic vaccine candidate and forms the basis of the RTS'S (Mosquirix®) malaria vaccine. However, high-yield production of full-length PfCSP with proper folding has been challenging. Here, we describe expression and purification of full-length PfCSP (containing 4 NVDP and 38 NANP repeats) with proper conformation by a simple three-step procedure in the Lactococcus lactis expression system.


Assuntos
Lactococcus lactis , Vacinas Antimaláricas , Malária Falciparum , Malária , Humanos , Lactococcus lactis/genética , Lactococcus lactis/metabolismo , Malária/prevenção & controle , Plasmodium falciparum/metabolismo , Proteínas de Protozoários/metabolismo , Anticorpos Antiprotozoários
20.
J Clin Microbiol ; 62(2): e0122223, 2024 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-38259072

RESUMO

To assess the performance of PLATELIA Toxo IgM (Bio-Rad) and Toxo ISAGA (BioMérieux) to detect anti-Toxoplasma IgM in infants at risk of congenital toxoplasmosis, a retrospective multicenter study was conducted comparing serological results obtained in the framework of routine diagnosis work-up for congenital toxoplasmosis. All infants born to mothers infected with T. gondii during pregnancy from 2010 to 2020 with at least 6 months of serological follow-up were included (n = 1,010). One thousand ten cases were included, of which 250 infants (24.75%) had congenital toxoplasmosis. A total of 1039 sera were included. The concordance between the two techniques was 96%, with kappa coefficient of 0.87, showing an almost perfect agreement between ISAGA and PLATELIA. Cumulative sensitivity and specificity were 73.2% and 99.5.% and 74.8% and 100% for ISAGA and PLATELIA, respectively. The mean time to detect IgM using ISAGA and PLATELIA tests was 6.9 ± 20.1 days and 5.6 ± 14.7 days, respectively not significant (ns). Finally, the sensitivity of ISAGA and PLATELIA to detect IgM antibodies in infected neonates at 5 days of life was 62% and 64%, respectively. Performances of PLATELIA Toxo IgM assay were comparable to the gold standard ISAGA. This enzyme-linked immunosorbent assay is suitable for routine serology for the diagnosis of congenital toxoplasmosis in newborns. IMPORTANCE This study will help clinical microbiologists to chose an alternative serological method for the neonatal diagnosis of congenital toxoplasmosis, once the gold standard technique ISAGA will be withdrawn next year.


Assuntos
Toxoplasma , Toxoplasmose Congênita , Toxoplasmose , Lactente , Gravidez , Feminino , Humanos , Recém-Nascido , Toxoplasmose Congênita/diagnóstico , Toxoplasmose/diagnóstico , Anticorpos Antiprotozoários , Imunoglobulina M
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