RESUMEN
Neospora caninum is an apicomplexan (family: Sarcocystidae) protozoan parasite with a global distribution. In the N. caninum life cycle, dogs and other related canids are the definitive hosts, while other animals such as water buffaloes (Bubalus bubalis) constitute the intermediate host for this parasite. In many countries, the water buffalo is of high economic importance, providing valuable high-quality products for human needs. Although knowledge concerning the prevalence of this parasite in intermediate animal host populations is crucial, data from water buffalo are scarce. Keeping this in mind, the aim of this study was to examine the presence and assess the prevalence rates of N. caninum infection in water buffaloes in Northern Greece, where this animal husbandry sector started to raise, as well as to determine associated risk factors, with the application of a commercially available Neospora ISCOM ELISA test kit, developed for the detection of antibodies against N. caninum in milk samples The study was conducted during January-June 2023 in a total of 172 individual raw milk samples, collected from dairy buffaloes, reared under a semi extensive system, in three different farms. Information on the status of N. caninum infection in buffaloes from Greece was so far unknown with a lack of epidemiological or risk factors associated. For the detection of N. caninum, the commercially available Neospora ISCOM ELISA test kit (SANOVIR ®, Svanova Biotech AB, Uppsala, Sweden) was utilized. Results demonstrated the presence of N. caninum in water buffaloes from Greece for the first time. All positive N. caninum animal were asymptomatic, with absence of any disease signs. The overall prevalence of infection was 22.10%, whereas the main risk factors include the presence of dogs as well as the low biosecurity measures.
Asunto(s)
Búfalos , Coccidiosis , Ensayo de Inmunoadsorción Enzimática , Leche , Neospora , Animales , Neospora/aislamiento & purificación , Neospora/inmunología , Búfalos/parasitología , Coccidiosis/veterinaria , Coccidiosis/epidemiología , Coccidiosis/parasitología , Grecia/epidemiología , Factores de Riesgo , Femenino , Ensayo de Inmunoadsorción Enzimática/veterinaria , Prevalencia , Leche/parasitología , Anticuerpos Antiprotozoarios/sangre , Estudios SeroepidemiológicosRESUMEN
Toxoplasmosis is one of the most common parasitic zoonoses and represents a significant health risk for humans, especially for immunodeficient patients. The main transmission route is by oral uptake of oocysts and consumption of undercooked meat of infected animals. Different species have been evaluated as possible reservoirs of the parasite, but few studies have been carried out to examine the role of horses in transmission of the disease. Given the proximity of these animals to humans and the widespread consumption of their meat in many countries, including the Mediterranean basin, it is important to determine the prevalence of T. gondii infection in this species. In this study, blood samples from 105 horses were collected and the presence of T. gondii was evaluated by serological and molecular methods. Antibodies against T. gondii of 12 horses (11.43%) were detected by enzyme-linked immunosorbent assay (ELISA), whereas 29 horses (27.62%) showed positive for PCR. Seroprevalence was related to use of the animals, being higher in horses used for dressage than in others. Purebreds had higher seroprevalence than crossbred animals. No differences between breed, sex or age were found. The results of this study confirm the presence of T. gondii infection in horses, highlighting the need to analyse the meat of this species before human consumption and to control of this infection in horses, as they could be an important reservoir of this zoonotic parasite.
Asunto(s)
Anticuerpos Antiprotozoarios , Ensayo de Inmunoadsorción Enzimática , Enfermedades de los Caballos , Toxoplasma , Toxoplasmosis Animal , Animales , Caballos/parasitología , Toxoplasmosis Animal/epidemiología , Toxoplasmosis Animal/diagnóstico , Toxoplasmosis Animal/parasitología , España/epidemiología , Enfermedades de los Caballos/parasitología , Enfermedades de los Caballos/epidemiología , Enfermedades de los Caballos/diagnóstico , Toxoplasma/aislamiento & purificación , Toxoplasma/genética , Estudios Seroepidemiológicos , Femenino , Anticuerpos Antiprotozoarios/sangre , Masculino , Ensayo de Inmunoadsorción Enzimática/veterinaria , Reacción en Cadena de la Polimerasa/veterinaria , PrevalenciaRESUMEN
Trypanosoma vivax infections are endemic in Africa, where they provoke trypanosomosis against which some local taurine breeds are tolerant and are thus named trypanotolerant. In Latin America, T. vivax was imported in 1919, since when it has been responsible for periodic outbreaks of the disease. This study assessed whether a South American taurine breed resilient to several parasitic and infectious diseases (Curraleiro Pé-Duro-CPD) can meet trypanotolerant criteria (control parasite proliferation, prevent anemia, survive without treatment, and maintain productivity). Three groups were established, each consisting of six animals (Group 1: CPD-infected; Group 2: Holstein/Gyr-infected; Group 3: Holstein/Gyr-uninfected, negative control). Groups 1 and 2 were infected with T. vivax on Day 0 and evaluated until day 532. Throughout the experimental period, parasitological (Woo and Brener), molecular (cPCR), serological (enzyme-linked immunosorbent assay - ELISA, indirect fluorescent antibody test - IFAT, immunochromatographic assay - IA), and clinical (hemogram, fever, weight loss) aspects were evaluated. During the acute phase of the disease, T. vivax was initially detected in Holstein/Gyr. Notably, the CPD animals restored their packed cell volume (PCV) values to the normal range 74 days after inoculations. In the chronic phase, two of the six CPD animals were positive by cPCR until D + 522 following immunosuppression with dexamethasone. Regarding serological aspects, the two CPD animals had positive tests until D + 532. The absence of T. vivax in blood during the chronic phase did not correspond to "self-cure". Holstein/Gyr animals exhibited fever on more evaluation days than CPD animals. Both breeds experienced weight loss, with Holstein/Gyr animals losing significantly more weight. On D + 25, the Holstein/Gyr group required treatment. During the 532 days, none of the CPD animals required treatment, even after being sensitized with dexamethasone. Animals from Group 3 tested negative for T. vivax throughout the experiment. This study demonstrated that CPD cattle fulfill the mentioned trypanotolerant criteria.
Asunto(s)
Trypanosoma vivax , Animales , Bovinos , Enfermedades de los Bovinos/parasitología , Enfermedades de los Bovinos/epidemiología , América Latina , Anticuerpos Antiprotozoarios/sangre , Tripanosomiasis Africana/veterinaria , Tripanosomiasis Africana/sangre , Tripanosomiasis Africana/parasitología , Masculino , Femenino , Tripanosomiasis Bovina/epidemiología , Tripanosomiasis Bovina/sangreRESUMEN
BACKGROUND: Asymptomatic carriage of infected red blood cells (iRBCs) can be prevalent in communities regardless of transmission patterns and can occur with infection of different Plasmodium species. Clinical immunity dampens the inflammatory responses leading to disease symptoms in malaria. The aim of this study was to define the immunological correlates of asymptomatic carriage of Plasmodium falciparum in a highly exposed population. METHODS: 142 asymptomatic Plasmodium-infected individuals greater than 2 years of age without fever (body temperature <37.5 â) were followed weekly for 10 weeks before being treated with artemisinin-based combination therapy (ACT). Plasma levels of 38 cytokines were measured at baseline by Luminex and the quantity and growth inhibitory activities of circulating parasite-reactive antibodies measured. The Plasmodium antigen tested included P. falciparum merozoite extract (ME) and schizont extract (SE), and the recombinant proteins erythrocyte binding antigen 175 (EBA-175) and merozoite surface protein 1 (MSP-119). RESULTS: Median levels of IgG against P. falciparum EBA-175 and MSP-119 at baseline were significantly higher in those older than 20 years of age compared with the younger age group and appeared to correlate with better parasite control. Amongst all participants there were no discernible changes in IgG levels over time. Parasite density was higher in the younger age group and associated with IL-10, TNF and MCP-1 levels. A balanced IL-10:TNF ratio was associated with asymptomatic malaria regardless of age, and balanced ratios of IL-10/TNF and IL-10/IFN-γ were the only significant correlate of maintenance of asymptomatic malaria over the course of the study in individuals 20 years of age and younger. CONCLUSION: The above findings indicate that asymptomatic carriage of P. falciparum in children living in a hyperendemic area occurs independently of IgG but is associated with a balanced inflammatory cytokine ratio.
Asunto(s)
Portador Sano , Citocinas , Inmunoglobulina G , Malaria Falciparum , Plasmodium falciparum , Humanos , Plasmodium falciparum/inmunología , Plasmodium falciparum/fisiología , Niño , Inmunoglobulina G/sangre , Preescolar , Malaria Falciparum/epidemiología , Malaria Falciparum/inmunología , Malaria Falciparum/parasitología , Citocinas/sangre , Adolescente , Masculino , Femenino , Portador Sano/epidemiología , Adulto Joven , Infecciones Asintomáticas/epidemiología , Anticuerpos Antiprotozoarios/sangre , Enfermedades Endémicas/estadística & datos numéricosRESUMEN
Tropical theileriosis is a lymphoproliferative disease caused by Theileria annulata and is transmitted by Ixodid ticks of the genus Hyalomma. It causes significant losses in livestock, especially in exotic cattle. The existing methods for controlling it, chemotherapeutic agents and a vaccine based on an attenuated schizont stage parasite, have several limitations. A promising solution to control this disease is the use of molecular vaccines based on potential immunogenic proteins of T. annulata. For this purpose, we selected five antigenic sequences of T. annulata, i.e. SPAG-1, Tams, TaSP, spm2, and Ta9. These were subjected to epitope prediction for cytotoxic T lymphocytes, B-cells, and helper T lymphocytes. CTL and B-cell epitopes with a higher score whereas those of HTL with a lower score, were selected for the construct. A single protein was constructed using specific linkers and evaluated for high antigenicity and low allergenicity. The construct was acidic, hydrophobic, and thermostable in nature. Secondary and tertiary structures of this construct were drawn using the PSIPRED and RaptorX servers, respectively. A Ramachandran plot showed a high percentage of residues in this construct in favorable, allowed, and general regions. Molecular docking studies suggested that the complex was stable and our construct could potentially be a good candidate for immunization trials. Furthermore, we successfully cloned it into the pET-28a plasmid and transformed it into the BL21 strain. A restriction analysis was performed to confirm the transformation of our plasmid. After expression and purification, recombinant protein of 49 kDa was confirmed by western blotting. An ELISA detected increased specific antibody levels in the sera of the immunized animals compared with the control group, and flow cytometric analysis showed a stronger cell-mediated immune response. We believe our multi-epitope recombinant protein has the potential for the large-scale application for disease prevention globally in the bovine population. This study will act as a model for similar parasitic challenges.
Asunto(s)
Inmunidad Celular , Inmunidad Humoral , Proteínas Recombinantes , Theileria annulata , Theileriosis , Theileria annulata/inmunología , Theileria annulata/genética , Animales , Bovinos , Theileriosis/inmunología , Theileriosis/parasitología , Theileriosis/prevención & control , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genética , Epítopos de Linfocito T/inmunología , Epítopos de Linfocito B/inmunología , Vacunas Antiprotozoos/inmunología , Proteínas Protozoarias/inmunología , Proteínas Protozoarias/genética , Simulación por Computador , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/genética , Anticuerpos Antiprotozoarios/inmunología , Anticuerpos Antiprotozoarios/sangreRESUMEN
Blood transfusion has a hazard of transmission of many pathogens, including Toxoplasma gondii (T. gondii) and other venereal infections. It is crucial to conduct epidemiological surveillance to detect the prevalence of these pathogens. The study aimed to assess the seroprevalence of T. gondii and common transfusable venereal infections among healthy blood donors in Menoufia Province, Egypt, and identify associated risk factors. Four hundred twenty individuals were recruited between January and April 2023 for cross-sectional descriptive research from the blood banks of Menoufia University medical hospitals. Collected blood samples were screened for anti-T. gondii IgM and IgG, HBsAg, anti-HCV antibodies, HIV p24 antigen and anti-HIV antibodies, and anti-Treponema pallidum antibodies. 46 (11.0%) and 22 donors (5.2%) individuals tested positive for anti-T. gondii IgG with a 95% CI (8.3-14.6) and IgM with a 95% CI (3.5-8.1), respectively, while one patient (0.2%) was positive for both antibodies. Regarding venereal infections, 12 (2.9%) were positive for HBV, 6 (1.4%) were positive for HCV, 7 (1.7%) were positive for HIV, and none of the tested population showed positivity for syphilis. Female gender, consumption of raw meat, agricultural environment, poor awareness about T. gondii, and blood group type (especially AB and O groups) were identified as independent risk factors for T. gondii infection. The study highlights the importance of testing blood donors for T. gondii and common transfusable venereal illnesses. Starting health education programs and preventative measures, such as suitable meat handling and cleanliness practices, is critical for minimizing the occurrence of these illnesses. Larger-scale additional study is advised to confirm these results and provide guidance for public health initiatives.
Asunto(s)
Donantes de Sangre , Enfermedades de Transmisión Sexual , Toxoplasma , Toxoplasmosis , Humanos , Egipto/epidemiología , Masculino , Toxoplasma/inmunología , Femenino , Toxoplasmosis/epidemiología , Toxoplasmosis/parasitología , Adulto , Enfermedades de Transmisión Sexual/epidemiología , Enfermedades de Transmisión Sexual/parasitología , Estudios Transversales , Estudios Seroepidemiológicos , Persona de Mediana Edad , Factores de Riesgo , Adulto Joven , Anticuerpos Antiprotozoarios/sangre , Prevalencia , Adolescente , Sífilis/epidemiología , Sífilis/sangreRESUMEN
The control of African trypanosomiasis (AT) in Eastern and Southern Africa, including Zambia, faces huge challenges due to the involvement of wild and domestic animal reservoirs. Free-roaming dogs in wildlife-populated and tsetse-infested villages of Zambia's Mambwe district are exposed to infectious tsetse bites. Consuming fresh raw game meat and bones further exacerbates their risk of contracting AT. We focus on the reservoir role of such dogs in maintaining and transmitting diverse species of trypanosomes that are infective to humans and livestock in Zambia's Mambwe district. A cohort of 162 dogs was enrolled for follow-up at 3 different time points from June to December 2018 in selected villages of Malama, Mnkhanya, and Nsefu chiefdoms of Mambwe district, eastern Zambia. Blood and serum were screened for AT by microscopy, GM6 ELISA, PCR (ITS1 and SRA), and Sanger sequencing. Out of the 162 dogs in the cohort, 40 were lost to follow-up and only 122 remained traceable at the end of the study. GM6 ELISA detected Trypanosoma antibodies in 121 dogs (74.7%) and ITS1-PCR detected DNA involving single and mixed infections of T. congolense, T. brucei, and suspected T. simiae or T. godfreyi in 115 dogs (70.9%). The human-infective T. b. rhodesiense was detected by SRA PCR in 67 dogs (41.4%), and some sequence data that support the findings of this study have been deposited in the GenBank under accession numbers OL961811, OL961812, and OL961813. Our study demonstrates that the Trypanosoma reservoir community in Zambia is wider than was thought and includes domesticated dogs. As dogs are active carriers of human and livestock-infective trypanosomes, they pose a risk of transmitting AT in endemic villages of Mambwe district as they are neglected and left untreated. To fully bring AT under control, countries such as Zambia where the role of animal reservoirs is important, should not limit their prevention and treatment efforts to livestock (especially cattle) but also include dogs that play an integral part in most rural communities.
Asunto(s)
Reservorios de Enfermedades , Enfermedades de los Perros , Tripanosomiasis Africana , Animales , Perros , Zambia/epidemiología , Tripanosomiasis Africana/epidemiología , Tripanosomiasis Africana/veterinaria , Tripanosomiasis Africana/transmisión , Tripanosomiasis Africana/parasitología , Enfermedades de los Perros/parasitología , Enfermedades de los Perros/epidemiología , Enfermedades de los Perros/transmisión , Reservorios de Enfermedades/parasitología , Humanos , Masculino , Femenino , Animales Domésticos/parasitología , Anticuerpos Antiprotozoarios/sangre , Trypanosoma/genética , Trypanosoma/aislamiento & purificaciónRESUMEN
Background: Transmission-blocking vaccines (TBVs) can effectively prevent the community's spread of malaria by targeting the antigens of mosquito sexual stage parasites. At present, only a few candidate antigens have demonstrated transmission-blocking activity (TBA) potential in P. vivax. Quiescin-sulfhydryl oxidase (QSOX) is a sexual stage protein in the rodent malaria parasite Plasmodium berghei and is associated with a critical role in protein folding by introducing disulfides into unfolded reduced proteins. Here, we reported the immunogenicity and transmission-blocking potency of the PvQSOX in P. vivax. Methods and findings: The full-length recombinant PvQSOX protein (rPvQSOX) was expressed in the Escherichia coli expression system. The anti-rPvQSOX antibodies were generated following immunization with the rPvQSOX in rabbits. A parasite integration of the pvqsox gene into the P. berghei pbqsox gene knockout genome was developed to express full-length PvQSOX protein in P. berghei (Pv-Tr-PbQSOX). In western blot, the anti-rPvQSOX antibodies recognized the native PvQSOX protein expressed in transgenic P. berghei gametocyte and ookinete. In indirect immunofluorescence assays, the fluorescence signal was detected in the sexual stages, including gametocyte, gamete, zygote, and ookinete. Anti-rPvQSOX IgGs obviously inhibited the ookinetes and oocysts development both in vivo and in vitro using transgenic parasites. Direct membrane feeding assays of anti-rPvQSOX antibodies were conducted using four field P. vivax isolates (named isolates #1-4) in Thailand. Oocyst density in mosquitoes was significantly reduced by 32.00, 85.96, 43.52, and 66.03% with rabbit anti-rPvQSOX antibodies, respectively. The anti-rPvQSOX antibodies also showed a modest reduction of infection prevalence by 15, 15, 20, and 22.22%, respectively, as compared to the control, while the effect was insignificant. The variation in the DMFA results may be unrelated to the genetic polymorphisms. Compared to the P.vivax Salvador (Sal) I strain sequences, the pvqsox in isolate #1 showed no amino acid substitution, whereas isolates #2, #3, and #4 all had the M361I substitution. Conclusions: Our results suggest that PvQSOX could serve as a potential P. vivax TBVs candidate, which warrants further evaluation and optimization.
Asunto(s)
Anticuerpos Antiprotozoarios , Vacunas contra la Malaria , Malaria Vivax , Plasmodium berghei , Plasmodium vivax , Proteínas Recombinantes , Plasmodium vivax/inmunología , Plasmodium vivax/genética , Plasmodium vivax/enzimología , Animales , Conejos , Vacunas contra la Malaria/inmunología , Anticuerpos Antiprotozoarios/inmunología , Malaria Vivax/prevención & control , Malaria Vivax/transmisión , Malaria Vivax/inmunología , Plasmodium berghei/inmunología , Plasmodium berghei/genética , Plasmodium berghei/enzimología , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Ratones , Escherichia coli/genética , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/genética , Proteínas Protozoarias/inmunología , Proteínas Protozoarias/genética , Proteínas Protozoarias/metabolismo , Femenino , Humanos , Inmunogenicidad Vacunal , Ratones Endogámicos BALB CRESUMEN
BACKGROUND: Plasmodium falciparum erythrocyte membrane protein 1 (PfEMP1) proteins are expressed on the surface of infected erythrocytes, mediating parasite sequestration in the vasculature. PfEMP1 is a major target of protective antibodies, but the features of the antibody response are poorly defined. METHODS: In Malawian children with cerebral or uncomplicated malaria, we characterized the antibody response to 39 recombinant PfEMP1 Duffy binding like (DBL) domains or cysteine-rich interdomain regions (CIDRs) in detail, including measures of antibody classes, subclasses, and engagement with Fcγ receptors and complement. Using elastic net regularized logistic regression, we identified a combination of seven antibody targets and Fc features that best distinguished between children with cerebral and uncomplicated malaria. To confirm the role of the selected targets and Fc features, we measured antibody-dependent neutrophil and THP-1 cell phagocytosis of intercellular adhesion molecule-1 (ICAM-1) and endothelial protein C (EPCR) co-binding infected erythrocytes. RESULTS: The selected features distinguished between children with cerebral and uncomplicated malaria with 87% accuracy (median, 80-96% interquartile range) and included antibody to well-characterized DBLß3 domains and a less well-characterized CIDRγ12 domain. The abilities of antibodies to engage C1q and FcγRIIIb, rather than levels of IgG, correlated with protection. In line with a role of FcγRIIIb binding antibodies to DBLß3 domains, antibody-dependent neutrophil phagocytosis of ICAM-1 and EPCR co-binding IE was higher in uncomplicated malaria (15% median, 8-38% interquartile range) compared to cerebral malaria (7%, 30-15%, p < 0.001). CONCLUSIONS: Antibodies associated with protection from cerebral malaria target a subset of PfEMP1 domains. The Fc features of protective antibody response include engagement of FcγRIIIb and C1q, and ability to induce antibody-dependent neutrophil phagocytosis of infected erythrocytes. Identifying the targets and Fc features of protective immunity could facilitate the development of PfEMP1-based therapeutics for cerebral malaria.
Asunto(s)
Anticuerpos Antiprotozoarios , Malaria Cerebral , Plasmodium falciparum , Proteínas Protozoarias , Humanos , Malaria Cerebral/inmunología , Malaui , Anticuerpos Antiprotozoarios/inmunología , Anticuerpos Antiprotozoarios/sangre , Proteínas Protozoarias/inmunología , Preescolar , Plasmodium falciparum/inmunología , Masculino , Femenino , Niño , Lactante , Molécula 1 de Adhesión Intercelular/inmunología , Receptor de Proteína C Endotelial/inmunología , Fagocitosis , Eritrocitos/parasitología , Eritrocitos/inmunología , Malaria Falciparum/inmunología , Antígenos de Protozoos/inmunologíaRESUMEN
BACKGROUND: Toxoplasma gondii is an intracellular opportunistic pathogenic protozoan that poses serious threats, particularly in immunocompromised individuals. In the absence of a robust prophylactic measure, the mitigation and management of toxoplasmosis present formidable challenges to public health. We recently found that GRA72 plays an important role in parasitophorous vacuole (PV) morphology, growth and virulence of T. gondii. However, whether gra72-deficient strain can be used as a vaccine remains unknown. METHODS: We first examined the attenuated virulence of gra72 gene knockout strain (PruΔgra72) and the parasite load in organs of the infected mice. Subsequently, we evaluated the immune-protective effects of the PruΔgra72 vaccination against challenge with various types of T. gondii tachyzoites and Pru cysts. Furthermore, levels of antibodies and cytokines induced by PruΔgra72 vaccination were examined. Statistical analysis was conducted by Student's t-test or Mantel-Cox log-rank test based on data obtained from three independent experiments with GraphPad Prism 8.0. RESULTS: We found that PruΔgra72 strain exhibited a significantly attenuated virulence even at the highest dose of 5 × 107 tachyzoites in Kunming mice model. The significant decrease of brain cyst burden and parasite load in the organs of the PruΔgra72-infected mice suggested its potentiality as a live-attenuated vaccine. Hence, we explored the protective immunity of PruΔgra72 vaccination against toxoplasmosis. Results showed that vaccination with 5 × 106 PruΔgra72 tachyzoites triggered a strong and sustained Th1-biased immune response, marked by significantly increased levels of anti-T. gondii IgG antibodies, and significantly higher levels of Th1 type cytokines (IL-2, IL-12 and IFN-γ) compared to that of Th2 type (IL-4 and IL-10). Vaccination with 5 × 106 PruΔgra72 tachyzoites in mice conferred long-term protection against T. gondii infection by less virulent tachyzoites (ToxoDB#9 PYS and Pru strains) and Pru cysts, provided partial protection against acute infection by high virulent Type I RH tachyzoites and significantly decreased brain cyst burden of chronically infected mice. CONCLUSIONS: The avirulent PruΔgra72 induced strong protective immunity against acute and chronic T. gondii infection and is a promising candidate for developing a safe and effective live-attenuated vaccine against T. gondii infection.
Asunto(s)
Anticuerpos Antiprotozoarios , Proteínas Protozoarias , Vacunas Antiprotozoos , Toxoplasma , Toxoplasmosis Animal , Vacunas Atenuadas , Animales , Toxoplasma/inmunología , Toxoplasma/genética , Ratones , Vacunas Antiprotozoos/inmunología , Vacunas Antiprotozoos/administración & dosificación , Vacunas Atenuadas/inmunología , Vacunas Atenuadas/administración & dosificación , Proteínas Protozoarias/inmunología , Proteínas Protozoarias/genética , Anticuerpos Antiprotozoarios/sangre , Femenino , Toxoplasmosis Animal/prevención & control , Toxoplasmosis Animal/inmunología , Citocinas/metabolismo , Virulencia , Carga de Parásitos , Modelos Animales de Enfermedad , Enfermedad Crónica , Toxoplasmosis/prevención & control , Toxoplasmosis/inmunología , Toxoplasmosis/parasitologíaRESUMEN
Toxoplasmosis is one of the most widespread zoonotic diseases in the world. Human infection rates range from 10% to 80% in many countries. Female cancer patients receiving chemotherapy are more susceptible to developing acute forms of toxoplasmosis, which can cause brain defects, neurological damage, and encephalitis. The aim of the present study was to investigate the effect of Toxoplasma gondii infection on the induction of interferon-gamma in breast cancer patients from Iraq. This descriptive cross-sectional study was performed on women had breast cancer in Al-Haboubi Teaching Hospital in Nasiriya City-Thi-Qar Province (Iraq) during the period from January to September 2022. Approximately three ml of blood was drawn from all participants and sera were collected. The Sera were then tested for Toxoplasma IgM, IgG, and IFN-γ (Nova Tec Immunodiagnostica GmbH, Germany) using the enzyme-linked immunosorbent assay (ELISA) kits according to the protocols of the manufacturer. Before blood collection, participants completed a printed questionnaire with some demographic information, such as age and place of residence. The total number of positive T. gondii infections from breast cancer patients in the current study was 60 (85.7%). The results of sample analysis by ELISA assay showed that 85.7% and 74.2% of patients were positive for IgG and IgM, respectively. The mean IFN-γ levels in breast cancer patients with toxoplasmosis, without toxoplasmosis, and in the control group were 47.66, 0.00, and 0.57 pg/ ml, respectively. Higher IgG and interferon gamma levels were detected in the group of breast cancer patients with toxoplasmosis than in the group without toxoplasmosis. According to the ELISA findings, T. gondii was the most common parasite in female cancer patients.
Asunto(s)
Neoplasias de la Mama , Interferón gamma , Toxoplasma , Toxoplasmosis , Adulto , Anciano , Femenino , Humanos , Persona de Mediana Edad , Anticuerpos Antiprotozoarios/sangre , Estudios Transversales , Inmunoglobulina G/sangre , Inmunoglobulina M/sangre , Interferón gamma/sangre , Interferón gamma/análisis , Irak/epidemiología , Toxoplasma/fisiologíaRESUMEN
The apical membrane antigen-1 (AMA-1) is a crucial target for malaria management and prevention strategies. While the immunogenicity of AMA-1 has been extensively studied for Plasmodium falciparum and Plasmodium vivax, there is a notable scarcity of information for Plasmodium malariae. In this study, recombinant PmAMA-1 was expressed in Escherichia coli, and its integrity was confirmed via western blotting and indirect immunofluorescence assays. Immunization of BALB/c mice with rPmAMA-1 emulsified in Freund's adjuvant resulted in significantly elevated specific IgG antibodies, predominantly IgG1. The immune response exhibited Th1, Th2, and Th17 phenotypes, with a notable Th1 bias. Antisera from immunized mice effectively recognized native PmAMA-1 on P. malariae. These results suggest that PmAMA-1 is a promising target for both vaccine development and diagnostic applications for P. malariae infections, offering dual preventive and diagnostic benefits in malaria control.
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Anticuerpos Antiprotozoarios , Antígenos de Protozoos , Malaria , Proteínas de la Membrana , Plasmodium malariae , Proteínas Protozoarias , Animales , Femenino , Ratones , Anticuerpos Antiprotozoarios/sangre , Anticuerpos Antiprotozoarios/inmunología , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/genética , Escherichia coli/genética , Inmunoglobulina G/sangre , Malaria/diagnóstico , Malaria/prevención & control , Malaria/inmunología , Vacunas contra la Malaria/inmunología , Vacunas contra la Malaria/administración & dosificación , Proteínas de la Membrana/inmunología , Proteínas de la Membrana/genética , Ratones Endogámicos BALB C , Plasmodium malariae/inmunología , Plasmodium malariae/genética , Proteínas Protozoarias/inmunología , Proteínas Protozoarias/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genéticaRESUMEN
Epidemiological studies and meta-analyses have shown a strong association between high seroprevalence of Toxoplasma gondii (T. gondii) and schizophrenia. Schizophrenic patients showed higher levels of anti-Toxoplasma immunoglobulins M and G (IgM and IgG) when compared to healthy controls. Previously, in a rat model, we demonstrated that the progeny of mothers immunized with T. gondii lysates before gestation had behavioral and social impairments during adulthood. Therefore, we suggested that T. gondii infection can trigger autoreactivity by molecularly mimicking host brain proteins. Here, we aimed to identify the occurrence of antigenic mimicry between T. gondii epitopes and host brain proteins. Using a bioinformatic approach, we predicted T. gondii RH-88 B cell epitopes and compared them to human cell-surface proteins involved in brain development and differentiation (BrainS). Five different algorithms for B-cell-epitope prediction were used and compared, resulting in 8584 T. gondii epitopes. We then compared T. gondii predicted epitopes to BrainS proteins by local sequence alignments using BLASTP. T. gondii immunogenic epitopes significantly overlapped with 42 BrainS proteins. Among these overlapping proteins essential for brain development and differentiation, we identified HSP90 and NOTCH receptors as the proteins most likely to be targeted by the maternally generated pathogenic antibodies due to their topological overlap at the extracellular region of their sequence. This analysis highlights the relevance of pregestational clinical surveillance and screening for potential pathogenic anti-T. gondii antibodies. It also identifies potential targets for the design of vaccines that could prevent behavioral and cognitive impairments associated with pre-gestational T. gondii exposure.
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Encéfalo , Epítopos de Linfocito B , Imitación Molecular , Toxoplasma , Toxoplasma/inmunología , Imitación Molecular/inmunología , Humanos , Epítopos de Linfocito B/inmunología , Encéfalo/parasitología , Encéfalo/inmunología , Encéfalo/metabolismo , Biología Computacional/métodos , Toxoplasmosis/inmunología , Animales , Anticuerpos Antiprotozoarios/inmunología , RatasRESUMEN
Toxoplasma gondii (T. gondii) is widely spread around the world, which can cause serious harm to immunosuppressed patients. Currently, the commercial test kits are poor at assessing T. gondii infection and vaccine effectiveness, making an urgent need to exploit effective enzyme-linked immunosorbent assay with great performance to compensate for this deficiency. Here, the TgIMP1 recombinant protein was expressed in E. coli BL(21) cells. The TgIMP1 was purified with affinity chromatography and the reactivity was retained with anti-TgIMP1 antibodies. The TgIMP1 was then used to develop an indirect ELISA (IMP1-iELISA) and the reaction conditions of IMP1-iELISA were optimized. As a result, the cut-off value was determined to be 0.2833 by analyzing the OD450nm values of forty T. gondii-negative sera. The coefficient of variation of 6 T. gondii-positive sera within and between runs were both less than 10%. The IMP1-iELISA was non-cross-reactive with the sera of cytomegalovirus, herpes virus, rubella virus, Cryptosporidium spp., Theileria spp., Neospora spp. and Plasmodium spp.. Furthermore, the sensitivity and specificity of IMP1-iELISA were 98.9% and 96.7%, respectively, based on testing 150 serum samples. The results suggest that this IMP1-iELISA is specific, sensitive, repeatable and can be applied to the detection of T. gondii infections in the medical and health industries.
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Anticuerpos Antiprotozoarios , Ensayo de Inmunoadsorción Enzimática , Toxoplasma , Toxoplasmosis , Animales , Humanos , Anticuerpos Antiprotozoarios/sangre , Antígenos de Protozoos/inmunología , Antígenos de Protozoos/genética , Ensayo de Inmunoadsorción Enzimática/métodos , Escherichia coli/genética , Inmunoglobulina G/sangre , Proteínas Protozoarias/inmunología , Proteínas Protozoarias/genética , Proteínas Recombinantes/inmunología , Proteínas Recombinantes/genética , Sensibilidad y Especificidad , Toxoplasma/inmunología , Toxoplasma/genética , Toxoplasmosis/diagnóstico , Toxoplasmosis/inmunología , Toxoplasmosis/parasitologíaRESUMEN
Entamoeba histolytica, the causative agent of amebiasis, is one of the top three parasitic causes of mortality worldwide. However, no vaccine exists against amebiasis. Using a lead candidate vaccine containing the LecA fragment of Gal-lectin and GLA-3M-052 liposome adjuvant, we immunized rhesus macaques via intranasal or intramuscular routes. The vaccine elicited high-avidity functional humoral responses as seen by the inhibition of amebic attachment to mammalian target cells by plasma and stool antibodies. Importantly, antigen-specific IFN-γ-secreting peripheral blood mononuclear cells (PBMCs) and IgG/IgA memory B cells (BMEM) were detected in immunized animals. Furthermore, antigen-specific antibody and cellular responses were maintained for at least 8 months after the final immunization as observed by robust LecA-specific BMEM as well as IFN-γ+ PBMC responses. Overall, both intranasal and intramuscular immunizations elicited a durable and functional response in systemic and mucosal compartments, which supports advancing the LecA+GLA-3M-052 liposome vaccine candidate to clinical testing.
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Administración Intranasal , Anticuerpos Antiprotozoarios , Entamoeba histolytica , Entamebiasis , Interferón gamma , Leucocitos Mononucleares , Liposomas , Macaca mulatta , Vacunas Antiprotozoos , Animales , Entamoeba histolytica/inmunología , Liposomas/inmunología , Liposomas/administración & dosificación , Vacunas Antiprotozoos/inmunología , Vacunas Antiprotozoos/administración & dosificación , Anticuerpos Antiprotozoarios/sangre , Anticuerpos Antiprotozoarios/inmunología , Leucocitos Mononucleares/inmunología , Entamebiasis/prevención & control , Entamebiasis/inmunología , Interferón gamma/inmunología , Interferón gamma/metabolismo , Inyecciones Intramusculares , Inmunogenicidad Vacunal , Adyuvantes de Vacunas/administración & dosificación , Adyuvantes Inmunológicos/administración & dosificación , Linfocitos B/inmunología , Inmunoglobulina G/sangre , Inmunoglobulina G/inmunología , Inmunoglobulina A/inmunología , Inmunoglobulina A/sangre , Antígenos de Protozoos/inmunología , Inmunidad Humoral , Memoria Inmunológica , Proteínas Protozoarias/inmunologíaRESUMEN
American Tegumentary Leishmaniasis (ATL) is a disease of high severity and incidence in Brazil, in addition to being a worldwide concern in public health. Leishmania amazonensis is one of the etiological agents of ATL, and the inefficiency of control measures, associated with the high toxicity of the treatment and the lack of effective immunoprophylactic strategies, makes the development of vaccines indispensable and imminent. In this light, the present study proposes to elaborate a chimeric protein (rChiP), based on the fusion of multiple epitopes of CD4+/CD8+ T cells, identified in the immunoproteome of the parasites L. amazonensis and L. braziliensis. The designed chimeric protein was tested in the L. amazonensis murine model of infection using the following formulations: 25 µg of the rChiP in saline (rChiP group) and 25 µg of the rChiP plus 25 µg of MPLA-PHAD® (rChiP+MPLA group). After completing immunization, CD4+ and CD8+ T cells, stimulated with SLa-Antigen or rChiP, showed an increased production of nitric oxide and intracytoplasmic pro-inflammatory cytokines, in addition to the generation of central and effector memory T cells. rChiP and rChiP+MPLA formulations were able to promote an effective protection against L. amazonensis infection determined by a reduction in the development of skin lesions and lower parasitic burden. Reduction in the development of skin lesions and lower parasitic burden in the vaccinated groups were associated with an increase of nitrite, CD4+/CD8+IFN-γ+TNF-α+ and CD4+/CD8+CD44highCD62Lhigh/low T cells, IgGTotal, IgG2a, and lower rates of IgG1 and CD4+/CD8+IL-10+. This data suggests that proposed formulations could be considered potential tools to prevent ATL.
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Adyuvantes Inmunológicos , Linfocitos T CD4-Positivos , Linfocitos T CD8-positivos , Epítopos de Linfocito T , Memoria Inmunológica , Vacunas contra la Leishmaniasis , Leishmaniasis Cutánea , Animales , Leishmaniasis Cutánea/prevención & control , Leishmaniasis Cutánea/inmunología , Linfocitos T CD8-positivos/inmunología , Linfocitos T CD4-Positivos/inmunología , Epítopos de Linfocito T/inmunología , Ratones , Vacunas contra la Leishmaniasis/inmunología , Femenino , Adyuvantes Inmunológicos/administración & dosificación , Ratones Endogámicos BALB C , Proteínas Recombinantes de Fusión/inmunología , Proteínas Recombinantes de Fusión/genética , Leishmania braziliensis/inmunología , Lípido A/análogos & derivados , Lípido A/inmunología , Anticuerpos Antiprotozoarios/inmunología , Citocinas/metabolismo , Citocinas/inmunología , Modelos Animales de Enfermedad , Antígenos de Protozoos/inmunologíaRESUMEN
Parasites have been associated with possible anticancer activity, including Trypanosoma cruzi, which has been linked to inhibiting the growth of solid tumors. To better understand this antitumor effect, we investigated the association of anti-T. cruzi antibodies with B cells of the acute lymphoblastic leukemia (ALL) SUPB15 cell line. The antibodies were generated in rabbits. IgGs were purified by affinity chromatography. Two procedures (flow cytometry (CF) and Western blot(WB)) were employed to recognize anti-T. cruzi antibodies on SUPB15 cells. We also used CF to determine whether the anti-T. cruzi antibodies could suppress SUPB15 cells. The anti-T. cruzi antibodies recognized 35.5% of the surface antigens of SUPB15. The complement-dependent cytotoxicity (CDC) results demonstrate the cross-suppression of anti-T. cruzi antibodies on up to 8.4% of SUPB15 cells. For the WB analysis, a band at 100 kDa with high intensity was sequenced using mass spectrometry, identifying the protein as nucleolin. This protein may play a role in the antitumor effect on T. cruzi. The anti-T. cruzi antibodies represent promising polyclonal antibodies that have the effect of tumor-suppressive cross-linking on cancer cells, which should be further investigated.
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Anticuerpos Antiprotozoarios , Leucemia-Linfoma Linfoblástico de Células Precursoras , Trypanosoma cruzi , Trypanosoma cruzi/inmunología , Leucemia-Linfoma Linfoblástico de Células Precursoras/inmunología , Humanos , Línea Celular Tumoral , Animales , Conejos , Anticuerpos Antiprotozoarios/inmunología , Proteínas de Unión al ARN/inmunología , Proteínas de Unión al ARN/metabolismo , Nucleolina , Fosfoproteínas/inmunología , Fosfoproteínas/metabolismoRESUMEN
Bovine neosporosis is a widespread parasitic disease associated with significant economic losses. Its effects on the reproductive performance of cows have resulted in losses that run into the hundreds of millions of US dollars in dairy industries in various countries (Reichel et al., Int J Parasitol 43:133-142, 2013). Due to outdated and scant information on the occurrence of Neospora caninum infection in South Africa, the study aimed to determine the seroprevalence and risk factors associated with infection in dairy cattle in South Africa. A total of 1401 blood samples were randomly collected from cattle on 48 dairy farms in seven of the nine provinces in South Africa. A close-ended questionnaire was used in a cross-sectional study to obtain farm-level and animal-level data. Serological testing was done using a commercial IDvet Screen® Neospora caninum Indirect ELISA. An overall seroprevalence, adjusted for test sensitivity and specificity, of 2.3% (95% CI, 1.3-4.1) was detected and 48% (23/48) of sampled farms had at least one animal testing positive. The highest seroprevalence of N. caninum was in the KwaZulu-Natal province with 7.5% (95% CI, 3.8-14.3), and the lowest in Western Cape with 0.1% (95% CI, 0-1.2). The highest within-farm seroprevalence of 25% was detected on a farm in the North West Province. In a multivariable logistic regression model, the odds of N. caninum seropositivity were higher in Holstein-Friesian cattle when compared to other breeds. Good hygiene was identified as a protective factor. Cattle left out on pasture had increased odds of testing positive for N. caninum compared to those that were penned. The odds of testing seropositive for N. caninum was higher on farms that practised segregation of cattle into different age groups. The purchase of replacement animals was a significant risk factor, as open herds had increased odds of N. caninum seropositivity. Cattle on farms that did not have a specific calving location were more likely to be seropositive. This is the first such study in South Africa and shows that N. caninum is widely distributed in the country at a low seroprevalence, but it may be a cause of concern on certain farms.
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Anticuerpos Antiprotozoarios , Enfermedades de los Bovinos , Coccidiosis , Neospora , Animales , Bovinos , Coccidiosis/epidemiología , Coccidiosis/veterinaria , Coccidiosis/parasitología , Sudáfrica/epidemiología , Estudios Seroepidemiológicos , Neospora/inmunología , Neospora/aislamiento & purificación , Enfermedades de los Bovinos/epidemiología , Enfermedades de los Bovinos/parasitología , Factores de Riesgo , Estudios Transversales , Anticuerpos Antiprotozoarios/sangre , Femenino , Ensayo de Inmunoadsorción Enzimática/veterinaria , Industria Lechera , Encuestas y CuestionariosRESUMEN
BACKGROUND: Cats are now recognized as competent hosts for Leishmania infantum and a blood source for sand fly vectors. Although canine leishmaniosis (CanL) is endemic in Mediterranean Basin countries, large-scale epidemiological studies are lacking for feline leishmaniosis (FeL). This study aimed to assess the prevalence of L. infantum infections, associated risk factors, clinical signs, and clinicopathological abnormalities in domestic cat populations from six Mediterranean Basin countries. METHODS: From 2019 to 2022, blood and serum samples of cats (n = 2067) living in Italy (n = 300), Greece (n = 297), Portugal (n = 295), France (n = 231), Israel (n = 313), and Spain (n = 631) were collected along with animal data (i.e., age, sex, breed, housing conditions, and geographical origin), clinical signs, and laboratory blood test parameters. Cats were grouped according to their age as kittens (up to 1 year), young (older than 1 and younger than 7 years), mature (between 7 and 10 years), and senior (older than 10 years). Serum samples were tested for L. infantum by immunofluorescence antibody test (IFAT) and enzyme-linked immunosorbent assay (ELISA), and blood samples of seropositive cats were tested for L. infantum kinetoplast deoxyribonucleic acid (kDNA). Viral infection by feline immunodeficiency virus (FIV) and feline leukemia virus (FeLV) was molecularly addressed in all cats enrolled. Statistical analysis was performed to evaluate the association between the risk of L. infantum infection and independent variables, and among co-infection of L. infantum with FIV and/or FeLV, clinical signs, and clinicopathological abnormalities. RESULTS: Overall, 17.3% (358/2067) of cats scored positive for L. infantum by serological tests. Specifically, 24.7% were from Portugal, 23.2% from Greece, 16.6% from Israel, 15% from Spain, 13.3% from France, and 12.6% from Italy. Leishmania infantum DNA was detected in 15 seropositive animals. Housing condition and FIV infection proved to be risk factors for FeL. Leishmania seropositivity was significantly associated with weight loss, lymphadenomegaly, gingivostomatitis, and oral ulcers, as well as with reduced albumin and albumin/globulin ratio, increased total globulins and total proteins, leukocytosis, and thrombocytosis. CONCLUSIONS: This study provides, for the first time, a large-scale epidemiological survey on FeL and its clinical presentation, revealing that L. infantum circulates among domestic cats, especially shelter/free-roaming and FIV-infected animals, living in CanL endemic countries of the Mediterranean Basin.
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Enfermedades de los Gatos , Leishmania infantum , Leishmaniasis Visceral , Animales , Gatos , Enfermedades de los Gatos/epidemiología , Enfermedades de los Gatos/parasitología , Enfermedades de los Gatos/virología , Leishmania infantum/aislamiento & purificación , Leishmania infantum/genética , Masculino , Femenino , Leishmaniasis Visceral/epidemiología , Leishmaniasis Visceral/veterinaria , Leishmaniasis Visceral/parasitología , Región Mediterránea/epidemiología , Factores de Riesgo , Prevalencia , España/epidemiología , Grecia/epidemiología , Portugal/epidemiología , Anticuerpos Antiprotozoarios/sangre , Virus de la Leucemia Felina/aislamiento & purificación , Virus de la Leucemia Felina/genética , Francia/epidemiología , Italia/epidemiología , Leishmaniasis/epidemiología , Leishmaniasis/veterinaria , Virus de la Inmunodeficiencia Felina/aislamiento & purificación , Israel/epidemiologíaRESUMEN
BACKGROUND: Toxoplasma gondii, a globally distributed zoonotic obligate intracellular parasite, infects a wide array of mammals, including humans, sheep, and birds. As a unique sheep breed in southwestern China, Yunnan semi-fine wool sheep occupies an important position in animal husbandry in Zhaotong due to its strong adaptability, high reproductive rate, and excellent wool quality. Lambs infected with T. gondii are prone to neurological symptoms and growth retardation, while T. gondii infection in ewes can cause abortions, stillbirths, and deformities, thus affecting sheep reproduction and sheep product quality. Meanwhile, mutton and dairy products contaminated with T. gondii can become potential sources of human infection, potentially threatening public health and safety. METHOD: To understand the T. gondii infection in semi-fine wool sheep in Zhaotong, Yunnan Province, 586 blood samples were collected and subjected to indirect hemagglutination assay (IHA) for T. gondii antibodies, and the infection-related factors were analyzed through cross-sectional analysis. In the meantime, nested PCR was conducted on a total of 217 samples collected from 31 rodents caught in and around the sheep breeding ground to test the T. gondii B1 gene in rodent tissues. RESULTS: A total of 94 sera tested positive for T. gondii antibodies, with a total positive rate of 16.04% (94/586) (95% CI: 14.77-20.89). Cross-sectional statistical analysis on factors related to semi-fine wool sheep infection rate, including sampling season, sex, age, and weight, suggested that age (< 6 months: 23.81%; 6-12 months: 11.74%; > 12 months: 15.83%) was a significant factor explaining the infection rate differences (P = 0.003 < 0.05, χ2 = 11.62, df = 2). Thus, age was considered a key risk factor for T. gondii infection in this study (odds ratio, OR = 2.35, 95% CI: 1.42-3.87). Nested PCR analysis on 217 (heart, liver, spleen, lung, kidney, brain, and muscle) tissues from the 31 rodents indicated that 11 tested positive. The total infection rate of rodents in and around the breeding ground was 35.48% (11/31), and 14 samples tested positive, with a positive infection rate of 6.45% (14/217). CONCLUSION: The T. gondii infection rates of semi-fine wool sheep and rodents from their breeding environment in Zhaotong, Yunnan Province, were high, necessitating enhanced prevention, control, and treatment measures to ensure the healthy breeding of semi-fine wool sheep and veterinary public health and safety.