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Brito RMDM, de Lima Bessa G, Bastilho AL, Dantas-Torres F, de Andrade-Neto VF, Bueno LL, Fujiwara RT, Magalhães LMD. Genetic diversity of Toxoplasma gondii in South America: occurrence, immunity, and fate of infection. Parasit Vectors 2023; 16:461. [PMID: 38115102 PMCID: PMC10729521 DOI: 10.1186/s13071-023-06080-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2023] [Accepted: 12/03/2023] [Indexed: 12/21/2023] Open
Abstract
Toxoplasma gondii is an intracellular parasite with a worldwide distribution. Toxoplasma gondii infections are of great concern for public health, and their impact is usually most severe in pregnant women and their foetuses, and in immunocompromised individuals. Displaying considerable genetic diversity, T. gondii strains differ widely according to geographical location, with archetypal strains predominantly found in the Northern Hemisphere and non-archetypal (atypical) strains, with highly diverse genotypes, found mainly in South America. In this review, we present an overview of the identification and distribution of non-archetypal strains of T. gondii. Special attention is paid to the strains that have been isolated in Brazil, their interaction with the host immunological response, and their impact on disease outcomes. The genetic differences among the strains are pivotal to the distinct immunological responses that they elicit. These differences arise from polymorphisms of key proteins released by the parasite, which represent important virulence factors. Infection with divergent non-archetypal strains can lead to unusual manifestations of the disease, even in immunocompetent individuals.
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Affiliation(s)
- Ramayana Morais de Medeiros Brito
- Laboratory of Immunobiology and Control of Parasites, Department of Parasitology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil
- Laboratory of Malaria and Toxoplasmosis Biology, Department of Microbiology and Parasitology, Biosciences Centre, Federal University of Rio Grande do Norte, Natal, Brazil
| | | | - Alexandre Lazoski Bastilho
- Laboratory of Malaria and Toxoplasmosis Biology, Department of Microbiology and Parasitology, Biosciences Centre, Federal University of Rio Grande do Norte, Natal, Brazil
| | | | - Valter Ferreira de Andrade-Neto
- Laboratory of Malaria and Toxoplasmosis Biology, Department of Microbiology and Parasitology, Biosciences Centre, Federal University of Rio Grande do Norte, Natal, Brazil
| | - Lilian Lacerda Bueno
- Laboratory of Immunobiology and Control of Parasites, Department of Parasitology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil
| | - Ricardo Toshio Fujiwara
- Laboratory of Immunobiology and Control of Parasites, Department of Parasitology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil.
| | - Luisa M D Magalhães
- Laboratory of Immunobiology and Control of Parasites, Department of Parasitology, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte, Brazil.
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Dos Santos EH, Barreira GA, Yamamoto L, Rocha MC, Rodrigues KA, Cruz MCP, Kanunfre KA, Okay TS. New Allele-Specific Oligonucleotide (ASO) amplifications for Toxoplasma gondii rop18 allele typing: Analysis of 86 human congenital infections in Brazil. Acta Trop 2023; 247:107011. [PMID: 37652181 DOI: 10.1016/j.actatropica.2023.107011] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/30/2023] [Revised: 08/25/2023] [Accepted: 08/28/2023] [Indexed: 09/02/2023]
Abstract
This study aimed to detect and differentiate Toxoplasma gondii by the allele typing of its polymorphic rop18 gene. For this purpose, a novel genotyping system using allele-specific oligonucleotides (ASOs) was designed, consisting of three ASO pairs. The first and third pairs specifically amplify rop18 allele I and allele III, while the second pair amplify both allele I and II. Genomic DNA from 86 congenital infections was analyzed by ASO-PCRs, successfully typing 82 (95.35%) samples. The remaining 4 samples (4.65%) required sequencing and single nucleotide polymorphism (SNP) analysis of the amplification products. The distribution of samples according to rop18 alleles was: 39.5% of allele III, 38.4% of allele II, 19.8% of mixed rop18 alleles (I/III or II/III), and 2.3% of allele I. The six severely compromised infants exhibited the highest parasite load levels and were infected during the first and early second trimesters of pregnancy. Among these cases, two were associated with rop18 allele I parasites, two with mixed rop18 alleles (I/III), one with allele II, and one with allele III parasites. In conclusion, all severe cases of congenital toxoplasmosis were infected during early pregnancy, but they were not exclusively associated with rop18 allele I parasites, as observed in murine toxoplasmosis. Furthermore, nearly one-fifth of parasites were non-archetypal, exhibiting more than one rop18 allele, indicating a higher genetic diversity of Toxoplasma gondii in this South American sample. Overall, a robust T. gondii rop18 allele typing was developed and suggested that congenital toxoplasmosis in humans involves complex mechanisms beyond the parasite genotype.
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Affiliation(s)
- Emilly Henrique Dos Santos
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, Brasil; Departamento de Pediatria, Faculdade de Medicina, Universidade de São Paulo, Brasil
| | - Gabriel Acca Barreira
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, Brasil; Faculdade Israelita de Ciências da Saúde Albert Einstein (FICSAE), São Paulo, Brasil
| | - Lidia Yamamoto
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, Brasil
| | - Mussya Cisotto Rocha
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, Brasil
| | - Karen Alessandra Rodrigues
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, Brasil; Departamento de Pediatria, Faculdade de Medicina, Universidade de São Paulo, Brasil
| | | | | | - Thelma Suely Okay
- Instituto de Medicina Tropical, Faculdade de Medicina, Universidade de São Paulo, Brasil; Departamento de Pediatria, Faculdade de Medicina, Universidade de São Paulo, Brasil.
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3
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Zeinali S, Khademvatan S, Jafari R, Vazifekhah S, Yousefi E, Behroozi-Lak T. Prevalence and risk factors of Toxoplasma gondii infection among women with miscarriage and their aborted fetuses in the northwest of Iran. PLoS One 2023; 18:e0283493. [PMID: 37883415 PMCID: PMC10602335 DOI: 10.1371/journal.pone.0283493] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2022] [Accepted: 03/11/2023] [Indexed: 10/28/2023] Open
Abstract
Toxoplasmosis is a worldwide disease of various animals and human and results from infection with the Toxoplasma gondii parasite. Abortion and congenital defects are important consequences of the T. gondii infection. The aim of this study was to determine the Toxoplasma-induced abortions among women with miscarriage and the presence of T. gondii in their aborted fetuses in Urmia, the northwest of Iran. This cross-sectional study was conducted with 215 women with abortion and their aborted fetuses, from 2020 to 2021. Seroprevalence of anti-Toxoplasma IgG and IgM were determined using the sera of the aforesaid women. Nested PCR was carried out using RE-529 gene sequences, and sequencing was performed using the T. gondii GRA6 gene on the remnant of pregnancy after abortion. The tissue positive samples were then subjected to another PCR on GRA6 gene and sequenced for genotyping. Among 215 serum samples of women with abortion, 70 (32.6%) were positive for anti-Toxoplasma IgG, and three (1.4%) were positive for IgM. The RE-529 sequence of T. gondii was positive in three (1.4%) of the aborted fetuses. The analysis of GRA6 gene indicated that all three positive samples carried a GRA6 allele (GRA6I) of T. gondii type I genotype. Our findings suggest that T. gondii is one of the causative agents of spontaneous abortion in West Azerbijan Province, the northwest of Iran.
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Affiliation(s)
- Shiva Zeinali
- Department of Medical Parasitology and Mycology& Cellular and Molecular Research Center, Cellular and Molecular Medicine Research Institute, Urmia University of Medical Sciences, Urmia, Iran
| | - Shahram Khademvatan
- Department of Medical Parasitology and Mycology& Cellular and Molecular Research Center, Cellular and Molecular Medicine Research Institute, Urmia University of Medical Sciences, Urmia, Iran
| | - Rasool Jafari
- Department of Medical Parasitology and Mycology& Cellular and Molecular Research Center, Cellular and Molecular Medicine Research Institute, Urmia University of Medical Sciences, Urmia, Iran
| | - Shabnam Vazifekhah
- Maternal and Childhood Obesity Research Center, Urmia University of Medical Sciences, Urmia, Iran
| | - Elham Yousefi
- Department of Medical Parasitology and Mycology& Cellular and Molecular Research Center, Cellular and Molecular Medicine Research Institute, Urmia University of Medical Sciences, Urmia, Iran
| | - Tahereh Behroozi-Lak
- Reproductive Health Research Center, Department of Infertility, Urmia University of Medical Sciences, Urmia, Iran
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Márquez-Mauricio A, Caballero-Ortega H, Gómez-Chávez F. Congenital Toxoplasmosis Diagnosis: Current Approaches and New Insights. Acta Parasitol 2023; 68:473-480. [PMID: 37368128 DOI: 10.1007/s11686-023-00693-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2022] [Accepted: 06/07/2023] [Indexed: 06/28/2023]
Abstract
PURPOSE The aim of this study is to describe and discuss current disadvantages in congenital toxoplasmosis (CT) diagnosis, and what can be improved or changed through new perspectives and technological advances. METHODS We used Pubmed, Cochrane, and EBSCO databases to research publications from 10 years to date describing current diagnostic methods for CT. The keywords used for this Mini-Review were Toxoplasma gondii, congenital toxoplasmosis, diagnosis, and prospects using Boolean operators such as AND, OR, identifying scientific publications highlighting the importance of implementing new diagnostic methods. RESULTS Current diagnosis methods have several disadvantages, i.e., time-consuming, low sensitivity or specificity, and non-cost effective, that bring up the necessity of improving or developing new approaches. Recombinant proteins can help improve specificity by generating tests that use circulating strains in a specific geographical region, SAG1 and BAG1, as they are expressed during a particular stage of the disease (acute or chronic, respectively), for its use in serological diagnoses, such as capture ELISA and immunochromatography. Point of Care (POC) tests are methods performed at the patient care site, which leads to rapid patient treatment; despite the advantages, several improvements and perspectives are necessary to be implemented globally. CONCLUSIONS Although already established diagnosis methods for CT may be sufficient in some regions, there is still a persistent demand to develop tests with higher throughput, cost, and time reduction in developing countries, where prevalence is high. New approaches in CT diagnosis, such as recombinant proteins, capture ELISA, immunochromatography, and POC tests methods, can increase performance in terms of specificity and sensitivity simplifying diagnostic tests' requirements.
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Affiliation(s)
| | | | - Fernando Gómez-Chávez
- Laboratorio de Enfermedades Osteoarticulares e Inmunológicas, Sección de Estudios de Posgrado e Investigación, ENMyH-Instituto Politécnico Nacional, Mexico City, Mexico.
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Gómez-Chávez F, Murrieta-Coxca JM, Caballero-Ortega H, Morales-Prieto DM, Markert UR. Host-pathogen interactions mediated by extracellular vesicles in Toxoplasma gondii infection during pregnancy. J Reprod Immunol 2023; 158:103957. [PMID: 37253287 DOI: 10.1016/j.jri.2023.103957] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2023] [Revised: 05/15/2023] [Accepted: 05/17/2023] [Indexed: 06/01/2023]
Abstract
Molecular communication between a pathogen and its host is crucial for a successful interplay. Extracellular vesicles (EVs) act as mediators for the delivery of molecular signals among pathogens or between pathogens and the host. Toxoplasma gondii (T. gondii), an intracellular parasite with a worldwide presence, produces EVs itself, or induces the secretion of EVs from infected host cells potentially having capacities to modulate the host immune response. T. gondii infection is particularly important during pregnancy. Depending on the gestational age at the time of infection, the parasite can be transmitted through the placenta to the fetus, causing clinical complications such as jaundice, hepatosplenomegaly, chorioretinitis, cranioencephalic abnormalities, or even death. T. gondii infection is related to a pro-inflammatory immune response in both mother and fetus, which may enhance parasite transmission, but the implication of EV signaling in this process remains unclear. In this review, we summarize the current knowledge on EV release from T. gondii and its human host cells in regard to the immunological consequences and the passage through the placenta.
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Affiliation(s)
- Fernando Gómez-Chávez
- Sección de Estudios de Posgrado e Investigación, Escuela Nacional de Medicina y Homeopatía-Instituto Politécnico Nacional, Mexico City, Mexico; Programa de Posgrado en Ciencia y Tecnología de Vacunas y Bioterapéuticos, Instituto Politécnico Nacional, Mexico City, Mexico
| | | | - Heriberto Caballero-Ortega
- Secretaría de Salud, Laboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Mexico City, Mexico
| | | | - Udo R Markert
- Placenta Lab, Department of Obstetrics, Jena University Hospital, Jena, Germany.
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Targa LS, dos Santos EH, Yamamoto L, Barreira GA, Rodrigues KA, Rocha MC, Kanunfre KA, Okay TS. Toxoplasma gondii SAG2, SAG3 and GRA6 alleles and single nucleotide polymorphism in congenital infections with known parasite load and clinical outcome. Rev Inst Med Trop Sao Paulo 2023; 65:e8. [PMID: 36722670 PMCID: PMC9886222 DOI: 10.1590/s1678-9946202365008] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 12/16/2022] [Indexed: 02/02/2023] Open
Abstract
Amniotic fluid DNA samples were genotyped by multilocus-nested-PCR-RFLP, but only three of 11 markers amplified 113 of 122 (92.6%) samples, resulting in 12 untyped and 101 partial non-archetypal genotypes. The 101 typed samples were subdivided into four groups: G1 with 73 samples (5'and 3' SAG2 allele I + SAG3 allele III + GRA6 allele III), 53 had parasite load ≤ 102 parasites/mL (43 asymptomatic, 10 mild infections), 17 had load > 102 and ≤ 103 (one mild, 13 moderate and three severe), and three had load > 103 parasites/mL (three severe); G2 with 22 samples (5'and 3' SAG2 allele I + SAG3 allele III), all parasite load levels ≤ 102 parasites/mL (18 asymptomatic and four mild); G3 with five samples (5' and 3' SAG2 allele I + SAG3 allele II), parasite load ≤ 102 parasites/mL (three asymptomatic and two mild); G4 with one sample (5' and 3' SAG2 allele II + SAG3 allele II + GRA6 allele I), a parasite load < 102 parasites/mL in an asymptomatic infant. After DNA sequencing, restriction sites confirmed SAG2, SAG3 and GRA6 alleles in 98.7%, 100% and 100% of the cases, respectively, while single nucleotide polymorphisms confirmed 90% of 5'-SAG2 allele I; 98.7% of 3'-SAG2 allele I; 98% of SAG-3 allele III, but only 40% of GRA6 allele III results. For the moment, partial non-archetypal genotypes of parasites did not show any relationship with either parasite load in amniotic fluid samples or clinical outcome of infants at the age of 12 months.
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Affiliation(s)
- Lília Spaleta Targa
- Universidade de São Paulo, Faculdade de Medicina, Instituto de Medicina Tropical de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, São Paulo, Brazil
| | - Emilly Henrique dos Santos
- Universidade de São Paulo, Faculdade de Medicina, Instituto de Medicina Tropical de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, São Paulo, Brazil,Universidade de São Paulo, Faculdade de Medicina, Departamento de Pediatria, São Paulo, São Paulo, Brazil
| | - Lidia Yamamoto
- Universidade de São Paulo, Faculdade de Medicina, Instituto de Medicina Tropical de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, São Paulo, Brazil
| | - Gabriel Acca Barreira
- Universidade de São Paulo, Faculdade de Medicina, Instituto de Medicina Tropical de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, São Paulo, Brazil,Faculdade Israelita de Ciências da Saúde Albert Einstein, São Paulo, São Paulo, Brazil
| | - Karen Alessandra Rodrigues
- Universidade de São Paulo, Faculdade de Medicina, Instituto de Medicina Tropical de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, São Paulo, Brazil,Universidade de São Paulo, Faculdade de Medicina, Departamento de Pediatria, São Paulo, São Paulo, Brazil
| | - Mussya Cisotto Rocha
- Universidade de São Paulo, Faculdade de Medicina, Instituto de Medicina Tropical de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, São Paulo, Brazil
| | - Kelly Aparecida Kanunfre
- Universidade de São Paulo, Faculdade de Medicina, Instituto de Medicina Tropical de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, São Paulo, Brazil
| | - Thelma Suely Okay
- Universidade de São Paulo, Faculdade de Medicina, Instituto de Medicina Tropical de São Paulo, Laboratório de Soroepidemiologia e Imunobiologia, São Paulo, São Paulo, Brazil,Universidade de São Paulo, Faculdade de Medicina, Departamento de Pediatria, São Paulo, São Paulo, Brazil
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Wang XC, Li TT, Elsheikha HM, Zheng XN, Zhao DY, Wang JL, Wang M, Zhu XQ. Effect of deleting four Toxoplasma gondii calcium-binding EGF domain-containing proteins on parasite replication and virulence. Parasitol Res 2023; 122:441-450. [PMID: 36471092 DOI: 10.1007/s00436-022-07739-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Accepted: 11/17/2022] [Indexed: 12/12/2022]
Abstract
Several calcium-binding proteins including calcium-dependent protein kinases play important roles in several facets of the intracellular infection cycle of the apicomplexan protozoan parasite Toxoplasma gondii. However, the role of the calcium-binding epidermal growth factor (EGF) domain-containing proteins (CBDPs) remains poorly understood. In this study, we examined the functions of four CBDP genes in T. gondii RH strain of type I by generating knock-out strains using CRISPR-Cas9 system. We investigated the ability of mutant strains deficient in CBDP1, CBDP2, CBDP3, or CBDP4 to form plaques, replicate intracellularly, and egress from the host cells. The results showed that no definite differences between any of these four CBDP mutant strains and the wild-type strain in terms of their ability to form plaques, intracellular replication, and egress. Additionally, CBDP mutants did not exhibit any significant attenuated virulence compared to the wild-type strain in mice. The expression profiles of CBDP2-4 genes were conserved among T. gondii strains of different genotypes, life cycle stages, and developmental forms. Whether other CBDP genes play any roles in the pathogenicity of T. gondii strains of different genotypes remains to be elucidated.
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Affiliation(s)
- Xin-Cheng Wang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
| | - Ting-Ting Li
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province, 610213, People's Republic of China
| | - Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Loughborough, LE12 5RD, UK
| | - Xiao-Nan Zheng
- Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province, 030801, People's Republic of China
| | - Dan-Yu Zhao
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
| | - Jin-Lei Wang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province, 610213, People's Republic of China
| | - Meng Wang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China
- Institute of Urban Agriculture, Chinese Academy of Agricultural Sciences, Chengdu, Sichuan Province, 610213, People's Republic of China
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, Gansu Province, 730046, People's Republic of China.
- Laboratory of Parasitic Diseases, College of Veterinary Medicine, Shanxi Agricultural University, Taigu, Shanxi Province, 030801, People's Republic of China.
- Key Laboratory of Veterinary Public Health of Higher Education of Yunnan Province, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, People's Republic of China.
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Milne GC, Webster JP, Walker M. Is the incidence of congenital toxoplasmosis declining? Trends Parasitol 2023; 39:26-37. [PMID: 36400672 DOI: 10.1016/j.pt.2022.10.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Revised: 10/20/2022] [Accepted: 10/21/2022] [Indexed: 11/17/2022]
Abstract
Prenatal infection with the protozoan parasite Toxoplasma gondii can cause congenital toxoplasmosis (CT), an often fatal or lifelong-disabling condition. Several studies of human populations have reported temporal decreases in seroprevalence, suggesting declining CT incidence. However, the consistency of this trend among diverse populations remains unclear, as does its implication for prenatal screening programmes, the major intervention against CT. Using temporally resolved data on the seroprevalence of T. gondii in various countries, we discuss how the parasite's changing epidemiology may affect trends in CT incidence in varying and counterintuitive ways. We argue that parasite stage-specific serology could be helpful for understanding underlying causes of secular changes in seroprevalence. Furthermore, we highlight the importance of updating cost-effectiveness estimates of screening programmes, accounting for neuropsychiatric sequelae.
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Affiliation(s)
- Gregory Colin Milne
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, Herts, AL9 7TA, UK; London Centre for Neglected Tropical Disease Research, Imperial College London Faculty of Medicine, London, UK.
| | - Joanne P Webster
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, Herts, AL9 7TA, UK; London Centre for Neglected Tropical Disease Research, Imperial College London Faculty of Medicine, London, UK
| | - Martin Walker
- Department of Pathobiology and Population Sciences, Royal Veterinary College, University of London, Herts, AL9 7TA, UK; London Centre for Neglected Tropical Disease Research, Imperial College London Faculty of Medicine, London, UK
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Garweg JG, Kieffer F, Mandelbrot L, Peyron F, Wallon M. Long-Term Outcomes in Children with Congenital Toxoplasmosis-A Systematic Review. Pathogens 2022; 11:pathogens11101187. [PMID: 36297244 PMCID: PMC9610672 DOI: 10.3390/pathogens11101187] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2022] [Revised: 10/10/2022] [Accepted: 10/11/2022] [Indexed: 11/07/2022] Open
Abstract
Even in the absence of manifestations at birth, children with congenital toxoplasmosis (CT) may develop serious long-term sequelae later in life. This systematic review aims to present the current state of knowledge to base an informed decision on how to optimally manage these pregnancies and children. For this, a systematic literature search was performed on 28 July 2022 in PubMed, CENTRAL, ClinicalTrials.gov, Google Scholar and Scopus to identify all prospective and retrospective studies on congenital toxoplasmosis and its long-term outcomes that were evaluated by the authors. We included 31 research papers from several countries. Virulent parasite strains, low socioeconomic status and any delay of treatment seem to contribute to a worse outcome, whereas an early diagnosis of CT as a consequence of prenatal screening may be beneficial. The rate of ocular lesions in treated children increases over time to 30% in European and over 70% in South American children and can be considerably reduced by early treatment in the first year of life. After treatment, new neurological manifestations are not reported, while ocular recurrences are observed in more than 50% of patients, with a mild to moderate impact on quality of life in European cohorts when compared to a significantly reduced quality of life in the more severely affected South American children. Though CT is rare and less severe in Europe when compared with South America, antenatal screening is the only effective way to diagnose and treat affected individuals at the earliest possible time in order to reduce the burden of disease and achieve satisfying outcomes.
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Affiliation(s)
- Justus G. Garweg
- Swiss Eye Institute, Rotkreuz, and Uveitis Clinic, Berner Augenklinik, Zieglerstrasse 29, 3007 Bern, Switzerland
- Department of Ophthalmology, Inselspital, University Hospital, 3010 Bern, Switzerland
- Correspondence:
| | - François Kieffer
- Assistance Publique-Hôpitaux de Paris, Hôpital Armand Trousseau, Service de Néonatologie, 75012 Paris, France
| | - Laurent Mandelbrot
- Assistance Publique-Hôpitaux de Paris, Hôpital Louis-Mourier Service de Gynécologie-Obstétrique, 178 rue des Renouillers, 92700 Colombes, France
- Inserm IAME-U1137, 75000 Paris, France
| | - François Peyron
- Hospices Civils de Lyon, Hôpital de la Croix Rousse, Department of Parasitology and Medical Mycology, 69004 Lyon, France
| | - Martine Wallon
- Hospices Civils de Lyon, Hôpital de la Croix Rousse, Department of Parasitology and Medical Mycology, 69004 Lyon, France
- Walking Team, Centre for Research in Neuroscience in Lyon, 69500 Bron, France
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10
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Guimarães Gois PS, Franco PS, Cota Teixeira S, Guirelli PM, de Araújo TE, da Fonseca Batistão DW, de Oliveira FC, Lícia Santos Ferreira G, de Oliveira Gomes A, Favoreto S, Mineo JR, de Freitas Barbosa B, Ferro EAV. Polarisation of human macrophages towards an M1 subtype triggered by an atypical Brazilian strain of Toxoplasma gondii results in a reduction in parasite burden. Folia Parasitol (Praha) 2022; 69. [DOI: 10.14411/fp.2022.020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Accepted: 06/16/2022] [Indexed: 11/19/2022]
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11
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Vargas-Villavicencio JA, Cañedo-Solares I, Correa D. Anti-Toxoplasma gondii IgM Long Persistence: What Are the Underlying Mechanisms? Microorganisms 2022; 10:microorganisms10081659. [PMID: 36014077 PMCID: PMC9415799 DOI: 10.3390/microorganisms10081659] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2022] [Revised: 08/11/2022] [Accepted: 08/12/2022] [Indexed: 11/16/2022] Open
Abstract
Diagnosis of Toxoplasma gondii acute infection was first attempted by detection of specific IgM antibodies, as for other infectious diseases. However, it was noted that this immunoglobulin declines slowly and may last for months or even years. Apart from the diagnostic problem imposed on clinical management, this phenomenon called our attention due to the underlying phenomena that may be causing it. We performed a systematic comparison of reports studying IgM antibody kinetics, and the data from the papers were used to construct comparative plots and other graph types. It became clear that this phenomenon is quite generalized, and it may also occur in animals. Moreover, this is not a technical issue, although some tests make more evident the prolonged IgM decay than others. We further investigated biological reasons for its occurrence, i.e., infection dynamics (micro-reactivation–encystment, reinfection and reactivation), parasite strain relevance, as well as host innate, natural B cell responses and Ig class-switch problems inflicted by the parasite. The outcomes of these inquiries are presented and discussed herein.
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Affiliation(s)
| | - Irma Cañedo-Solares
- Laboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Mexico City 04530, Mexico
| | - Dolores Correa
- Dirección de Investigación/Centro de Investigación en Ciencias de la Salud, FCS, Universidad Anáhuac México Campus Norte, Av Universidad Anáhuc 46, Lomas Anáhuac, Huixquilucan 52786, Mexico
- Correspondence: ; Tel.: +52-(55)-5627-0210-7637
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12
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Vertical transmission and pathological findings in the mother, the placenta and the offspring, during first and last thirds of gestation in a mouse model of congenital toxoplasmosis. Parasitol Int 2022; 91:102640. [PMID: 35933034 DOI: 10.1016/j.parint.2022.102640] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2022] [Revised: 07/26/2022] [Accepted: 07/30/2022] [Indexed: 11/23/2022]
Abstract
We performed a study of congenital toxoplasmosis of the first and third gestation periods in mice, and determined its effects on the embryos/fetuses, the placentae and the maternal organs. We infected pregnant BALB/c mice by i.v. injection of 2.5-10.0 × 106 tachyzoites of the ME49 T. gondii strain and euthanized them 72 h later. The tissues were analyzed by histopathology, immunohistochemistry and parasite-specific qPCR. Infections with the lowest dose induced remarkably different changes in the two thirds: a) all doses diminished the number of products/litter, the lowest dose only by 14%; but most embryos still visible were degenerated in the case of the first period, while the fetuses of the last third were perfectly preserved; b) the transmission rate in the first third was relatively high, but with a very low parasite burden; c) with the lowest dose, strong vascular changes (congestion, thrombosis and hemorrhage) predominated in the placentas of the first period, while they were absent in the last third; d) necrosis caused by T. gondii to maternal organs was much stronger during the last gestation period than in the first. Our results suggest that the vascular alterations at the placenta of the first third of pregnancy prevent embryo from large parasite burden, but provoke its death by starvation. In the last gestation period, there was poor control of parasite dissemination to the placenta and the fetus, but there was greater capacity of the product to defend itself from T. gondii.
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13
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Hurt K, Kodym P, Stejskal D, Zikan M, Mojhova M, Rakovic J. Toxoplasmosis impact on prematurity and low birth weight. PLoS One 2022; 17:e0262593. [PMID: 35025961 PMCID: PMC8758008 DOI: 10.1371/journal.pone.0262593] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2021] [Accepted: 12/30/2021] [Indexed: 11/18/2022] Open
Abstract
Background Toxoplasma gondii, one of the most common parasites, causes toxoplasmosis, one of the most frequent zoonotic diseases worldwide. T. gondii infects about one-third of the world’s population. T. gondii infection is generally considered a major risk for spontaneous abortion, prematurity and low birth weight in the animal sphere. Less commonly, a toxoplasma serological profile is correlated with the particular data of delivery. Acute T. gondii infection during pregnancy often leads to spontaneous abortion and/or a severe injury of the eyes, brain, and other structures of the foetus. Latent T. gondii infection of pregnant women could lead to less obvious but important changes during pregnancy, including the end product of pregnancy and the timing of labour. This study aimed to contribute to the current knowledge by comparing serological T. gondii profiles of pregnant women with prematurity and low birth weights of newborns. Material and methods A retrospective study design was adopted. The study participants included a cohort of 1733 pregnant women who consecutively gave birth to their children and underwent regular antenatal biochemical screening between the 14th and 16th weeks of pregnancy. Prematurity was defined as the liveborn preterm delivery in gestational age of pregnancy <37 weeks. Low birth weight was defined as weight at birth of ≤2499 grams. The complement-fixation test (CFT) provided serological profiles for toxoplasmosis that expresses the overall levels of toxoplasma immunoglobulins of all classes. Enzyme-linked immunosorbent assay (ELISA) tests for IgG and IgM were used simultaneously. IgM positivity helped to differentiate acute from the latent stage of toxoplasmosis. Birth data, especially the week of delivery and fetal weight, were evaluated accordingly. Results Of the 1733 pregnant women, 25% were diagnosed as latent toxoplasma positive, and 75% as toxoplasma negative. There were 87 premature deliveries versus 1646 timely births. We observed 88 low birth weights and 1645 normal fetal weights. We found a statistically significant association between latent toxoplasmosis and prematurity, χ2(1) = 5.471, p = .019 and between latent toxoplasmosis and low birth weight of newborns, χ2(1) = 7.663, p = .006. There was a 1.707 times higher risk of prematurity for toxoplasma-positive women, while the risk for low birth weight was 1.861 times higher. The strength of both tests of association was mild. We tested the correlation between the levels of CFT titres and week of delivery and weight of newborns. No association was found between the level of latent toxoplasmosis and the week of delivery and fetal weight. Conclusion Latent toxoplasmosis was associated with premature birth rate and lower birth weight of newborns. The odds of premature delivery was 1.7 and low birth weight 1.9 times higher in women with latent toxoplasmosis compared to toxoplasma negative women. Even though the strength of the association in our large sample is relatively mild, the combination of latent toxoplasmosis with other adverse factors could cause serious harm. Whole CFT and specific IgG levels of latent toxoplasmosis are not linked to the severity of prematurity or low birth weight in newborns.
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Affiliation(s)
- Karel Hurt
- Obstetrics and Gynaecology dpt., First Faculty of Medicine, Charles University Prague, Prague, Czech Republic
- * E-mail:
| | - Petr Kodym
- National Institute of Public Health in Prague, Prague, Czech Republic
| | | | - Michal Zikan
- Obstetrics and Gynaecology dpt., First Faculty of Medicine, Charles University Prague, Prague, Czech Republic
| | - Martina Mojhova
- Obstetrics and Gynaecology dpt., First Faculty of Medicine, Charles University Prague, Prague, Czech Republic
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14
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Subekti DT, Ekawasti F, Desem MI, Azmi Z. Toxoplasma gondii virulence prediction using hierarchical cluster analysis based on coding sequences (CDS) of sag1, gra7 and rop18. J Vet Sci 2021; 22:e88. [PMID: 34854270 PMCID: PMC8636655 DOI: 10.4142/jvs.2021.22.e88] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Revised: 09/09/2021] [Accepted: 09/22/2021] [Indexed: 11/20/2022] Open
Abstract
Toxoplasma gondii consists of three genotypes, namely genotype I, II and III. Based on its virulence, T. gondii can be divided into virulent and avirulent strains. This study intends to evaluate an alternative method for predicting T. gondii virulence using hierarchical cluster analysis based on complete coding sequences (CDS) of sag1, gra7 and rop18 genes. Dendrogram was constructed using UPGMA with a Kimura 80 nucleotide distance measurement. The results showed that the prediction errors of T. gondii virulence using sag1, gra7 and rop18 were 7.41%, 6.89% and 9.1%, respectively. Analysis based on CDS of gra7 and rop18 was able to differentiate avirulent strains into genotypes II and III, whereas sag1 failed to differentiate.
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Affiliation(s)
- Didik T Subekti
- Indonesia Research Center for Veterinary Science, Bogor, West Java 16124, Indonesia.
| | - Fitrine Ekawasti
- Indonesia Research Center for Veterinary Science, Bogor, West Java 16124, Indonesia
| | | | - Zul Azmi
- Goats Research Station, Sei Putih, North Sumatra 20585, Indonesia
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15
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Rojas-Pirela M, Medina L, Rojas MV, Liempi AI, Castillo C, Pérez-Pérez E, Guerrero-Muñoz J, Araneda S, Kemmerling U. Congenital Transmission of Apicomplexan Parasites: A Review. Front Microbiol 2021; 12:751648. [PMID: 34659187 PMCID: PMC8519608 DOI: 10.3389/fmicb.2021.751648] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2021] [Accepted: 09/01/2021] [Indexed: 12/17/2022] Open
Abstract
Apicomplexans are a group of pathogenic protists that cause various diseases in humans and animals that cause economic losses worldwide. These unicellular eukaryotes are characterized by having a complex life cycle and the ability to evade the immune system of their host organism. Infections caused by some of these parasites affect millions of pregnant women worldwide, leading to various adverse maternal and fetal/placental effects. Unfortunately, the exact pathogenesis of congenital apicomplexan diseases is far from being understood, including the mechanisms of how they cross the placental barrier. In this review, we highlight important aspects of the diseases caused by species of Plasmodium, Babesia, Toxoplasma, and Neospora, their infection during pregnancy, emphasizing the possible role played by the placenta in the host-pathogen interaction.
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Affiliation(s)
- Maura Rojas-Pirela
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile.,Facultad de Farmacia y Bioanálisis, Universidad de Los Andes, Mérida, Venezuela
| | - Lisvaneth Medina
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Maria Verónica Rojas
- Instituto de Biología, Pontificia Universidad Católica de Valparaíso, Valparaíso, Chile
| | - Ana Isabel Liempi
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Christian Castillo
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Núcleo de Investigación Aplicada en Ciencias Veterinarias y Agronómicas, Facultad de Medicina Veterinaria y Agronomía, Universidad de Las Américas, Santiago, Chile
| | | | - Jesús Guerrero-Muñoz
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
| | - Sebastian Araneda
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile.,Facultad de Salud y Odontología, Universidad Diego Portales, Santiago, Chile
| | - Ulrike Kemmerling
- Instituto de Ciencias Biomédicas, Facultad de Medicina, Universidad de Chile, Santiago, Chile
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16
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Li J, Zhao J, Yang X, Wen Y, Huang L, Ma D, Shi J. One severe case of congenital toxoplasmosis in China with good response to azithromycin. BMC Infect Dis 2021; 21:920. [PMID: 34488656 PMCID: PMC8422759 DOI: 10.1186/s12879-021-06619-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2021] [Accepted: 08/26/2021] [Indexed: 11/11/2022] Open
Abstract
BACKGROUND Most infants infected with Toxoplasma gondii are completely asymptomatic at birth, yet they may develop ocular and neurological sequelae in the first few months of life. Cases of congenital toxoplasmosis with severe jaundice early after birth combined with pancytopenia and splenomegaly are extremely rare. Here, we report on a rare case of congenital toxoplasmosis presenting with severe jaundice and hemolysis early after birth combined with pancytopenia and splenomegaly. CASE PRESENTATION A male preterm infant with severe jaundice and splenomegaly was admitted to our department. Laboratory examinations revealed severe hyperbilirubinemia, increased reticulocytes, and pancytopenia. After comprehensive analysis and examination, the final diagnosis was congenital toxoplasmosis, and the infant was treated with azithromycin and subsequently trimethoprim-sulfamethoxazole. Regular follow-up revealed congenital toxoplasmosis in both eyes, which was surgically treated, while neurofunctional assessment results were unremarkable. In this case of congenital toxoplasmosis combined with severe jaundice, we treated the infant with two courses of azithromycin, followed by trimethoprim-sulfamethoxazole after the jaundice resolved. Clinical follow-up indicated that this treatment was effective with few side effects; thus, this report may serve as a valuable clinical reference. CONCLUSIONS Timely diagnosis and adequate treatment are closely associated with congenital toxoplasmosis-related prognosis. Infants with congenital toxoplasmosis require long-term follow-up, focusing on nervous system development and ophthalmology.
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Affiliation(s)
- Jiao Li
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jing Zhao
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Xiaoyan Yang
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Yang Wen
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, Sichuan, China
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, 610041, Sichuan, China
| | - Liang Huang
- Department of Pharmacy/Evidence-based Pharmacy Center, West China Second University Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
| | - Dan Ma
- Department of Rehabilitation Medicine, West China Second University Hospital of Sichuan University, Chengdu, 610041, Sichuan, China
| | - Jing Shi
- Department of Pediatrics, West China Second University Hospital, Sichuan University, Chengdu, 610041, Sichuan, China.
- Key Laboratory of Obstetric & Gynecologic and Pediatric Diseases and Birth Defects of Ministry of Education, Sichuan University, Chengdu, 610041, Sichuan, China.
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17
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Toxoplasma gondii in Slaughtered Sheep in High- and Low-Humidity Regions in the South of Iran: Molecular Prevalence and Genotype Identification. Vet Med Int 2021; 2021:5576771. [PMID: 34326981 PMCID: PMC8277495 DOI: 10.1155/2021/5576771] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 06/28/2021] [Indexed: 12/18/2022] Open
Abstract
Toxoplasma gondii is one of the most common meat-born zoonoses that infect all warm-blooded animals and humans. Sheep (Ovis aries) is one of the main reservoirs of T. gondii worldwide, and the infections induce various sequels, such as abortion and stillbirth. The present study aimed to identify the effects of humidity on the prevalence of T. gondii in sheep in high- and low-humidity regions. Heart samples from 200 slaughtered sheep (140 samples from a high-humidity region and 60 samples from a low-humidity region) were collected from Hormozgan Province (south of Iran). The samples were tested by nested PCR targeting the RE gene. Genotyping was performed by the PCR-RFLP method using the SAG3 and GRA6 genes. Some isolates were sequenced and recorded in the GenBank. T. gondii DNA was detected in 10.71 percent of the samples from the highly humid region, whereas no positive samples were detected in the low-humidity region. Genotyping revealed that all isolates belonged to the T. gondii type III genotype. Our study indicated that humidity is an important factor for the prevalence of T. gondii in sheep. Additionally, our study also showed the dominance of type III strain of T. gondii in sheep in the south of Iran.
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18
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Hernandez-Jover M, Culley F, Heller J, Ward MP, Jenson I. Semi-quantitative food safety risk profile of the Australian red meat industry. Int J Food Microbiol 2021; 353:109294. [PMID: 34147838 DOI: 10.1016/j.ijfoodmicro.2021.109294] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2020] [Revised: 04/20/2021] [Accepted: 06/07/2021] [Indexed: 01/16/2023]
Abstract
In 2017-18, the Australian red meat (beef, sheep and goat species) industry generated more than $AUD 13 billion in export trade alone and is therefore of substantial importance to the Australian GDP. With both relatively high amounts of domestic red meat consumption and dependence on international markets, food safety risk is constantly reassessed so as to maintain a resilient industry sector. The current study aimed to conduct a food safety risk rating for the Australian red meat industry. In 2002, a food safety risk profile was developed for the Australian red meat industry. It included raw and processed meat products of cattle, sheep and goats and considered microbiological, chemical and physical hazards. The current risk rating was undertaken during 2017 and 2018. The first step was to conduct a hazard characterization, which involved a review of literature and data on foodborne outbreaks, pathogen surveillance and product recalls, and an expert elicitation process with 15 Australian food safety experts. This process identified the Hazard:Product:Process combinations to be considered and the likelihood of contamination at the point of consumption. These likelihood ratings were then combined with hazard severity ratings to qualitatively estimate the relative risk posed by each combination. Combinations with a moderate-to-high risk were included in the semi-quantitative risk rating using Risk Ranger v2, a tool that allows an estimation of the public health risk of hazard: product combinations and a ranking of this risk. The Risk Ranger tool provides a risk ranking (RR), ranging from 0 (no risk) to 100 (every member of the population eats a meal that contains a lethal dose of the hazard every day). STEC E. coli O157 (RR 35-39) and Salmonella spp. (RR 33-37) in undercooked hamburgers and Listeria monocytogenes in ready-to-eat products (RR 35-38) were combinations which had the highest (moderate) risk for the general and susceptible populations. In addition, Toxoplasma gondii in undercooked lamb was identified as posing a high risk among pregnant women (RR 49). The study provides an updated food safety risk profile for the Australian red meat industry which, considering the available information, suggests red meat products do not pose a high food safety risk. The methodology developed in this study provides an easy to implement approach to profile and prioritise food safety risk and relies on data that can generated in most situations.
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Affiliation(s)
- Marta Hernandez-Jover
- Graham Centre for Agricultural Innovation (An alliance between Charles Sturt University and NSW Department of Primary Industries), Charles Sturt University, School of Animal and Veterinary Sciences, Locked Bag 588, Wagga Wagga, NSW 2678, Australia; School of Animal and Veterinary Sciences, Charles Sturt University, School of Animal and Veterinary Sciences, Locked Bag 588, Wagga Wagga, NSW 2678, Australia.
| | - Fiona Culley
- Graham Centre for Agricultural Innovation (An alliance between Charles Sturt University and NSW Department of Primary Industries), Charles Sturt University, School of Animal and Veterinary Sciences, Locked Bag 588, Wagga Wagga, NSW 2678, Australia; School of Animal and Veterinary Sciences, Charles Sturt University, School of Animal and Veterinary Sciences, Locked Bag 588, Wagga Wagga, NSW 2678, Australia
| | - Jane Heller
- Graham Centre for Agricultural Innovation (An alliance between Charles Sturt University and NSW Department of Primary Industries), Charles Sturt University, School of Animal and Veterinary Sciences, Locked Bag 588, Wagga Wagga, NSW 2678, Australia; School of Animal and Veterinary Sciences, Charles Sturt University, School of Animal and Veterinary Sciences, Locked Bag 588, Wagga Wagga, NSW 2678, Australia
| | - Michael P Ward
- The University of Sydney, School of Veterinary Science, 425 Werombi Road, Camden, NSW 2570, Australia
| | - Ian Jenson
- Meat & Livestock Australia, PO Box 1961, North Sydney, NSW 2059, Australia
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19
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Goldberg-Murow M, Cedillo-Peláez C, Concha-Del-Río LE, Cheja-Kalb R, Salgar-Henao MJ, Orozco-Velasco E, Luna-Pastén H, Gómez-Chávez F, Ibarra A, Correa D. Autoantibodies Against Ubiquitous and Confined Antigens in Patients With Ocular, Neuro-Ophthalmic and Congenital Cerebral Toxoplasmosis. Front Immunol 2021; 12:606963. [PMID: 34054794 PMCID: PMC8149787 DOI: 10.3389/fimmu.2021.606963] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2020] [Accepted: 04/26/2021] [Indexed: 11/13/2022] Open
Abstract
Toxoplasma gondii infection can trigger autoreactivity by different mechanisms. In the case of ocular toxoplasmosis, disruption of the blood-retinal barrier may cause exposure of confined retinal antigens such as recoverin. Besides, cross-reactivity can be induced by molecular mimicry of parasite antigens like HSP70, which shares 76% identity with the human ortholog. Autoreactivity can be a determining factor of clinical manifestations in the eye and in the central nervous system. We performed a prospective observational study to determine the presence of autoantibodies against recoverin and HSP70 by indirect ELISA in the serum of 65 patients with ocular, neuro-ophthalmic and congenital cerebral toxoplasmosis. We found systemic autoantibodies against recoverin and HSP70 in 33.8% and 15.6% of individuals, respectively. The presence of autoantibodies in cases of OT may be related to the severity of clinical manifestations, while in cases with CNS involvement they may have a protective role. Unexpectedly, anti-recoverin antibodies were found in patients with cerebral involvement, without ocular toxoplasmosis; therefore, we analyzed and proved cross-reactivity between recoverin and a brain antigen, hippocalcin, so the immunological phenomenon occurring in one immune-privileged organ (e.g. the central nervous system) could affect the environment of another (egg. the eye).
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Affiliation(s)
- Monica Goldberg-Murow
- Laboratorio de Inmunología Exprimental, Instituto Nacional de Pediatría, CDMX, Mexico.,Centro de Investigación de Ciencias de la Salud, Universidad Anáhuac, Huixquilucan, Mexico
| | - Carlos Cedillo-Peláez
- Laboratorio de Inmunología Exprimental, Instituto Nacional de Pediatría, CDMX, Mexico
| | - Luz Elena Concha-Del-Río
- Clínica de Enfermedades Inflamatorias Oculares, Asociación Para Evitar la Ceguera en México, I.A.P., CDMX, Mexico
| | - Rashel Cheja-Kalb
- Clínica de Enfermedades Inflamatorias Oculares, Asociación Para Evitar la Ceguera en México, I.A.P., CDMX, Mexico
| | - María José Salgar-Henao
- Clínica de Enfermedades Inflamatorias Oculares, Asociación Para Evitar la Ceguera en México, I.A.P., CDMX, Mexico
| | - Eduardo Orozco-Velasco
- Clínica de Enfermedades Inflamatorias Oculares, Asociación Para Evitar la Ceguera en México, I.A.P., CDMX, Mexico
| | - Héctor Luna-Pastén
- Laboratorio de Inmunología Exprimental, Instituto Nacional de Pediatría, CDMX, Mexico
| | - Fernando Gómez-Chávez
- Laboratorio de Inmunología Exprimental, Instituto Nacional de Pediatría, CDMX, Mexico.,Cátedras CONACyT-Instituto Nacional de Pediatría, CDMX, Mexico.,Departamento de Formación Básica Disciplinaria, ENMyH-IPN, CDMX, Mexico
| | - Antonio Ibarra
- Centro de Investigación de Ciencias de la Salud, Universidad Anáhuac, Huixquilucan, Mexico
| | - Dolores Correa
- Laboratorio de Inmunología Exprimental, Instituto Nacional de Pediatría, CDMX, Mexico
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20
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Gómez-Chávez F, Correa D, Navarrete-Meneses P, Cancino-Diaz JC, Cancino-Diaz ME, Rodríguez-Martínez S. NF-κB and Its Regulators During Pregnancy. Front Immunol 2021; 12:679106. [PMID: 34025678 PMCID: PMC8131829 DOI: 10.3389/fimmu.2021.679106] [Citation(s) in RCA: 34] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2021] [Accepted: 04/23/2021] [Indexed: 12/25/2022] Open
Abstract
The transcriptional factor NF-κB is a nuclear factor involved in both physiological and pathological processes. This factor can control the transcription of more than 400 genes, including cytokines, chemokines, and their modulators, immune and non-immune receptors, proteins involved in antigen presentation and cell adhesion, acute phase and stress response proteins, regulators of apoptosis, growth factors, other transcription factors and their regulators, as well as different enzymes; all these molecules control several biological processes. NF-κB is a tightly regulated molecule that has also been related to apoptosis, cell proliferation, inflammation, and the control of innate and adaptive immune responses during onset of labor, in which it has a crucial role; thus, early activation of this factor may have an adverse effect, by inducing premature termination of pregnancy, with bad outcomes for the mother and the fetus, including product loss. Reviews compiling the different activities of NF-κB have been reported. However, an update regarding NF-κB regulation during pregnancy is lacking. In this work, we aimed to describe the state of the art around NF-κB activity, its regulatory role in pregnancy, and the effect of its dysregulation due to invasion by pathogens like Trichomonas vaginalis and Toxoplasma gondii as examples.
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Affiliation(s)
- Fernando Gómez-Chávez
- Secretaría de Salud, Cátedras CONACyT-Instituto Nacional de Pediatría, Mexico City, Mexico.,Secretaría de Salud, Laboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Mexico City, Mexico.,Departamento de Formación Básica Disciplinaria, Escuela Nacional de Medicina y Homeopatía-Instituto Politécnico Nacional, Mexico City, Mexico
| | - Dolores Correa
- Dirección de Investigación, Universidad Anáhuac, Huixquilucan, Mexico
| | - Pilar Navarrete-Meneses
- Laboratorio de Genética y Cáncer, Instituto Nacional de Pediatría, Secretaría de Salud Mexico City, Mexico City, Mexico
| | - Juan Carlos Cancino-Diaz
- Laboratorio de Inmunomicrobiología, Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas-Instituto Politécnico Nacional, Mexico City, Mexico
| | - Mario Eugenio Cancino-Diaz
- Laboratorio de Inmunidad Innata, Departamento de Inmunología, ENCB-Instituto Politécnico Nacional, Mexico City, Mexico
| | - Sandra Rodríguez-Martínez
- Laboratorio de Inmunidad Innata, Departamento de Inmunología, ENCB-Instituto Politécnico Nacional, Mexico City, Mexico
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21
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Zhang ZW, Li TT, Wang JL, Liang QL, Zhang HS, Sun LX, Zhu XQ. Functional Characterization of Two Thioredoxin Proteins of Toxoplasma gondii Using the CRISPR-Cas9 System. Front Vet Sci 2021; 7:614759. [PMID: 33521087 PMCID: PMC7841047 DOI: 10.3389/fvets.2020.614759] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/07/2020] [Accepted: 12/16/2020] [Indexed: 01/01/2023] Open
Abstract
Toxoplasmosis caused by infection with Toxoplasma gondii is an important parasitic zoonosis with a worldwide distribution. In this study, we examined the functions of two thioredoxins (namely CTrp26 and CTrx1) of T. gondii tachyzoites by generation of HA tag strains or gene deficient parasites in Type I RH strain (ToxoDB#10). Immunofluorescence analysis (IFA) was used to investigate the subcellular localization of the thioredoxins (Trxs). Results of IFA showed that both CTrp26 and CTrx1 were located in the cytoplasm of T. gondii. Functional characterizations of CTrp26 and CTrx1-deficient parasites were performed by plaque assay, intracellular replication, egress, H2O2 resistance, detection of reactive oxygen species (ROS) level and total antioxidant capacity (T-AOC) assays in vitro, as well as mouse infection in vivo. Our results showed that deletion of CTrp26 or CTrx1 did not influence the ability of T. gondii RH strain to replicate, egress, form plaque, resist H2O2 exposure, maintain the ROS level, and T-AOC, and also did not serve as virulence factors in Kunming mice. Taken together, these results provide new properties of the two Trxs. Although they are not essential for RH strain, they may have roles in other strains of this parasite due to their different expression patterns, which warrants future research.
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Affiliation(s)
- Zhi-Wei Zhang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Ting-Ting Li
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Jin-Lei Wang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Qin-Li Liang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Hai-Sheng Zhang
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Li-Xiu Sun
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China
| | - Xing-Quan Zhu
- State Key Laboratory of Veterinary Etiological Biology, Key Laboratory of Veterinary Parasitology of Gansu Province, Lanzhou Veterinary Research Institute, Chinese Academy of Agricultural Sciences, Lanzhou, China.,College of Veterinary Medicine, Shanxi Agricultural University, Taigu, China.,Key Laboratory of Veterinary Public Health of Higher Education of Yunnan Province, College of Veterinary Medicine, Yunnan Agricultural University, Kunming, China
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Almeria S, Dubey JP. Foodborne transmission of Toxoplasma gondii infection in the last decade. An overview. Res Vet Sci 2020; 135:371-385. [PMID: 33148402 DOI: 10.1016/j.rvsc.2020.10.019] [Citation(s) in RCA: 52] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Revised: 10/14/2020] [Accepted: 10/20/2020] [Indexed: 01/07/2023]
Abstract
Toxoplasmosis is a zoonotic disease of global distribution and importance. It is caused by the protozoan parasite Toxoplasma gondii, the only species in the Toxoplasma genus. This parasite can infect most warm-blooded animals, including humans and livestock. Main routes of transmission are by ingestion of tissue cysts in raw or undercooked meat of infected animals, ingestion of raw vegetables or water contaminated with T. gondii oocysts from cat feces, and transplacental. Around one-third of human beings are chronically infected with T. gondii. Most infections appear to be asymptomatic in immunocompetent persons, but toxoplasmosis can be fatal to the fetus and immunocompromised adults. Water and foodborne outbreaks have been caused by this parasite worldwide, but few are well documented. Importantly, T. gondii is a parasite of high importance in animal health, causing reproductive failure, particularly in small ruminants, and clinical toxoplasmosis in many species. This overview discusses the knowledge of T. gondii infections in the last decade focusing on the foodborne transmission of this parasite.
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Affiliation(s)
- S Almeria
- Department of Health and Human Services, Food and Drug Administration, Center for Food Safety and Nutrition, Office of Applied Research and Safety Assessment, Division of Virulence Assessment, Laurel, MD 20708, USA.
| | - J P Dubey
- USA Department of Agriculture, Agricultural Research Service, Beltsville Agricultural Research Service, Animal Parasitic Disease Laboratory, Building 1001, BARC-East, Beltsville, MD 20705-2350, USA
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23
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Toxoplasmosis in pregnancy. Eur J Obstet Gynecol Reprod Biol 2020; 255:44-50. [PMID: 33075679 DOI: 10.1016/j.ejogrb.2020.10.003] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2020] [Revised: 09/30/2020] [Accepted: 10/05/2020] [Indexed: 11/23/2022]
Abstract
Toxoplasmosis is one of the common chronic infections caused by the parasite Toxoplasma gondii. Even though its infection in healthy non-pregnant women is self-limited and largely asymptomatic, the main concern is the risk to the fetus by vertical transmission in pregnancy. Congenital toxoplasmosis can result in permanent neurological damage and even serious morbidity such as blindness. Screening programs are implemented in various countries depending on the prevalence and virulence of the parasite in the respective regions. Upon diagnosis of infection, appropriate antibiotic therapy should be initiated as it has been proven to reduce the risk of fetal transmission. Primary prevention remains the key intervention to avoid the infection and hence patient education is an important aspect of the management.
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Pleyer U, Gross U, Schlüter D, Wilking H, Seeber F. Toxoplasmosis in Germany. DEUTSCHES ARZTEBLATT INTERNATIONAL 2020; 116:435-444. [PMID: 31423982 DOI: 10.3238/arztebl.2019.0435] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2018] [Revised: 05/23/2019] [Accepted: 05/23/2019] [Indexed: 01/16/2023]
Abstract
BACKGROUND With approximately 30% of the world population infected, Toxoplasma gondii is one of the most widespread pathogenic parasites in both humans and animals and a major problem for health economics in many countries. METHODS This review is based on the findings of individual studies, meta-analyses, and Cochrane Reviews retrieved by a selective literature survey of the Medline and Google Scholar databases. RESULTS Current data indicate a high rate of Toxoplasma gondii infection in Germany, ranging from 20% to 77% depending on age (95% confidence interval for 18- to 29-year-olds [17.0; 23.1]; for 70- to 79-year-olds [72.7; 80.5]). Male sex, caring for a cat, and a body mass index of 30 or more are independent risk factors for seroconversion. Postnatally acquired (food-related) infec- tion is predominant, but maternal-to-fetal transmission still plays an important role. While most infections are asymptomatic, congenital toxoplasmosis and reactivated Toxoplasma encephalitis in immunosuppressed persons (transplant recipients and others) are sources of considerable morbidity. Toxoplasma gondii infection of the retina is the most common cause of infectious uveitis in Germany. The diagnosis and treatment of this type of parasitic infection are particular to the specific organs involved in the individual patient. CONCLUSION Desirable steps for the near future include development of an effective treatment for the cystic stage and identifica- tion of biomarkers to assess the risk of reactivation and predict the disease course.
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Affiliation(s)
- Uwe Pleyer
- Department of Ophthalmology, Charité Campus Virchow, University Faculty of Medicine, Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health; Institute of Medical Microbiology and German Reference Laboratory for Toxoplasma Infection, Faculty of Medicine University of Göttingen; Institute of Medical Microbiology and Hospital Epidemiology, Hannover Medical School (MHH); Unit 35: Gastrointestinal Infections, Zoonoses and Tropical Infections, Robert Koch Institute, Berlin; Unit 16: Mycotic and parasitic agents and mycobacteria, Robert Koch Institute, Berlin
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Gómez-Chávez F, Cañedo-Solares I, Ortiz-Alegría LB, Flores-García Y, Figueroa-Damián R, Luna-Pastén H, Gómez-Toscano V, López-Candiani C, Arce-Estrada GE, Bonilla-Ríos CA, Mora-González JC, García-Ruiz R, Correa D. A Proinflammatory Immune Response Might Determine Toxoplasma gondii Vertical Transmission and Severity of Clinical Features in Congenitally Infected Newborns. Front Immunol 2020; 11:390. [PMID: 32231666 PMCID: PMC7082359 DOI: 10.3389/fimmu.2020.00390] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2019] [Accepted: 02/19/2020] [Indexed: 01/01/2023] Open
Abstract
Toxoplasma gondii is the etiological agent of toxoplasmosis. Mother-to-child transmission of this parasite can occur during pregnancy. Newborns with congenital toxoplasmosis may develop central nervous system impairment, with severity ranging from subclinical manifestations to death. A proinflammatory/regulated specific immune profile is crucial in the defense against the parasite; nevertheless, its role in the infected pregnant women and the congenitally infected offspring has been poorly explored, and there is still no consensus about its relation to parasite vertical transmission or to severity and dissemination in the congenitally infected newborns. This work aimed to characterize these relations by means of principal component and principal factor analyses. For this purpose, we determined the specific production of the four immunoglobulin G antibody subclasses, cytokines, and lymphocyte proliferation in the T. gondii–infected pregnant women−10 who transmitted the infection to their offspring and seven who did not—as well as in 11 newborns congenitally infected and grouped according to disease severity (five mild and six moderate/severe) and dissemination (four local and seven disseminated). We found that the immune response of nontransmitter women differed from that of the transmitters, the latter having a stronger proinflammatory response, supporting a previous report. We also found that newborns who developed moderate/severe disease presented higher levels of lymphocyte proliferation, particularly of CD8+ and CD19+ cells, a high proportion of tumor necrosis factor α producers, and reduced expression of the immune modulator transforming growth factor β, as opposed to children who developed mild clinical complications. Our results suggest that a distinctive, not regulated, proinflammatory immune response might favor T. gondii vertical transmission and the development of severe clinical manifestations in congenitally infected newborns.
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Affiliation(s)
- Fernando Gómez-Chávez
- Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico.,Cátedras CONACyT-Instituto Nacional de Pediatría, Mexico City, Mexico.,Departamento de Formación Básica Disciplinaria, ENMyH-IPN, Mexico City, Mexico
| | | | | | | | | | - Héctor Luna-Pastén
- Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | | | | | | | | | | | - Ricardo García-Ruiz
- Laboratorio de Cannabinoides, Facultad de Medicina, UNAM, Mexico City, Mexico
| | - Dolores Correa
- Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
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Xicoténcatl-García L, Enriquez-Flores S, Correa D. Testing New Peptides From Toxoplasma gondii SAG1, GRA6, and GRA7 for Serotyping: Better Definition Using GRA6 in Mother/Newborns Pairs With Risk of Congenital Transmission in Mexico. Front Cell Infect Microbiol 2019; 9:368. [PMID: 31709197 PMCID: PMC6819317 DOI: 10.3389/fcimb.2019.00368] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Accepted: 10/09/2019] [Indexed: 01/23/2023] Open
Abstract
Toxoplasma gondii variant influences clinical profile in human congenital and ocular toxoplasmosis. Parasite genotyping represents a challenge due to insufficient amount of genetic material of the protozoan in the host samples, and isolates are hard to obtain, especially from pediatric patients. An alternative is serotyping, which is based on the presence of specific antibodies against polymorphic proteins related to virulence; the more widely used are GRA6 and GRA7, but most works report cross reactions among the classical strains (I, II, and III). We designed new peptides of GRA6, GRA7, and SAG1 proteins, with more SNPs among the three clonal strains than those previously designed. This was done by identifying BcR and polymorphic epitopes by means of bioinformatics; then we designed peptides with linkers joining the specific regions and predicted their 3D structure. With the commercial molecules synthesized on the basis of these designs, we tested 86 serum samples from 42 mother/newborn pairs and two congenitally infected newborns, by indirect ELISA. We implemented a strategy to determine the serotype based on scatter plots and a mathematical formula, using ratios among reactivity indexes to peptides. We found low frequency of samples reactive to GRA7 and SAG1, and cross reactions between GRA6 serotypes I and III; we modified these later peptides and largely improved distinction among the three clonal strains. The chronicity of the infection negatively affected the reactivity index against the peptides. Serotyping both members of the mother/child pair improves the test, i.e., among 26% of them only one member was positive. Serotype I was the most frequent (38%), which was congruent with previous genotyping results in animals and humans of the same area. This serotype was significantly more frequent among mothers who transmitted the infection to their offspring than among those who did not (53 vs. 8%, p = 0.04) and related to disease dissemination in congenitally infected children, although non-significantly. In conclusion, serotyping using the improved GRA6 peptide triad is useful to serotype T. gondii in humans and could be implemented for clinical management and epidemiological studies, to provide information on the parasite type in specific areas.
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Affiliation(s)
- Lizbeth Xicoténcatl-García
- Laboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Sergio Enriquez-Flores
- Laboratorio de Errores Innatos del Metabolismo y Tamiz, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
| | - Dolores Correa
- Laboratorio de Inmunología Experimental, Instituto Nacional de Pediatría, Secretaría de Salud, Mexico City, Mexico
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Detection and genotypic characterization of Toxoplasma gondii DNA within the milk of Mongolian livestock. Parasitol Res 2019; 118:2005-2008. [PMID: 30982139 PMCID: PMC6521982 DOI: 10.1007/s00436-019-06306-w] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Accepted: 03/26/2019] [Indexed: 02/05/2023]
Abstract
Toxoplasma gondii is a global, zoonotic parasite capable of infecting any warm-blooded host. Toxoplasmosis can cause a variety of illnesses including abortions and congenital defects in humans, sheep, and goats. Congenital toxoplasmosis is considered to have the highest global disease burden of any foodborne illness in humans. This study examined the potential role of milk as a route of T. gondii transmission between livestock and humans within Mongolian herders, a little-studied population which relies heavily on animals. Milk of Mongolian sheep, goats and Bactrian camels was tested for the presence of T. gondii DNA, and a survey was conducted to ascertain what behavioral and environmental factors were present that might potentiate T. gondii infection within these Mongolian communities. T. gondii DNA was detected in samples from one sheep and five camels. Sequence analysis of DNA from camel milk revealed that two were from potentially virulent T. gondii genotypes. This has implications for public health in the region, as milk is an extremely important source of nutrition and our survey results imply that some people believe consumption of raw camel milk carries health benefits. This is the first report of T. gondii DNA in Bactrian camel milk as well as the first genotypic characterization of T. gondii within Mongolia.
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28
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Franco PS, Gois PSG, de Araújo TE, da Silva RJ, de Freitas Barbosa B, de Oliveira Gomes A, Ietta F, Dos Santos LA, Dos Santos MC, Mineo JR, Ferro EAV. Brazilian strains of Toxoplasma gondii are controlled by azithromycin and modulate cytokine production in human placental explants. J Biomed Sci 2019; 26:10. [PMID: 30665403 PMCID: PMC6340180 DOI: 10.1186/s12929-019-0503-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2018] [Accepted: 01/10/2019] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND Toxoplasma gondii is a protozoan parasite that causes congenital toxoplasmosis by transplacental transmission. Parasite strains are genetically diverse and disease severity is related to the genotype. In Uberlândia city, Brazil, two virulent strains were isolated: TgChBrUD1 and TgChBrUD2. Congenital toxoplasmosis is more prevalent in South America compared to Europe, and more often associated with severe symptoms, usually as a result of infection with atypical strains. METHODS Considering that T. gondii has shown high genetic diversity in Brazil, the effectiveness of traditional treatment may not be the same, as more virulent strains of atypical genotypes may predominate. Thus, the aim of this study were to evaluate the Brazilian strain infection rate in human villous explants and the azithromycin efficacy with regard to the control of these strains compared to traditional therapy. Villi were infected with RH, ME49, TgChBrUD1 or TgChBrUD2 strains and treated with azithromycin, spiramycin or a combination of pyrimethamine plus sulfadiazine. The villous viability was analyzed by LDH assay and morphological analysis. Parasite proliferation, as well as production of cytokines was analyzed by qPCR and ELISA, respectively. Statistical analysis was performed using the GraphPad Prism 5.0. RESULTS The treatments were not toxic and TgChBrUD1 infected villi showed a higher parasite burden compared with others strains. Treatments significantly reduced the intracellular proliferation of T. gondii, regardless of the strain. TgChBrUD1-infected villi produced a larger amount of MIF, IL-6 and TGF-β1 compared with other infected villi. Azithromycin treatment increased MIF production by RH- or TgChBrUD2-infected villi, but in ME49- or TgChBrUD1-infected villi, the MIF production was not altered by treatment. On the other hand, azithromycin treatment induced lower IL-6 production by ME49- or TgChBrUD1-infected villi. CONCLUSIONS Azithromycin treatment was effective against T. gondii Brazilian strains compared with conventional treatment. Also, the TgChBrUD1 strain replicated more in villi and modulated important cytokines involved in parasite control, showing that different strains use different strategies to evade the host immune response and ensure their survival.
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Affiliation(s)
- Priscila Silva Franco
- Laboratório de Imunofisiologia da Reprodução, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Av. Pará, 1720, Building: 2B, CEP, Uberlândia, 38405-320, Brazil
| | - Paula Suellen Guimarães Gois
- Laboratório de Imunofisiologia da Reprodução, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Av. Pará, 1720, Building: 2B, CEP, Uberlândia, 38405-320, Brazil
| | - Thádia Evelyn de Araújo
- Laboratório de Imunofisiologia da Reprodução, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Av. Pará, 1720, Building: 2B, CEP, Uberlândia, 38405-320, Brazil
| | - Rafaela José da Silva
- Laboratório de Imunofisiologia da Reprodução, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Av. Pará, 1720, Building: 2B, CEP, Uberlândia, 38405-320, Brazil
| | - Bellisa de Freitas Barbosa
- Laboratório de Imunofisiologia da Reprodução, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Av. Pará, 1720, Building: 2B, CEP, Uberlândia, 38405-320, Brazil
| | - Angelica de Oliveira Gomes
- Laboratório de Biologia Celular, Instituto de Ciências Biomédicas e Naturais, Universidade Federal do Triângulo Mineiro, Uberaba, Brazil
| | - Francesca Ietta
- Department of Life Sciences, University of Siena, Siena, Italy
| | - Lara Affonso Dos Santos
- Laboratório de Imunofisiologia da Reprodução, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Av. Pará, 1720, Building: 2B, CEP, Uberlândia, 38405-320, Brazil
| | - Maria Célia Dos Santos
- Laboratório de Imunofisiologia da Reprodução, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Av. Pará, 1720, Building: 2B, CEP, Uberlândia, 38405-320, Brazil
| | - José Roberto Mineo
- Laboratório de Imunoparasitologia, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Uberlândia, Brazil
| | - Eloisa Amália Vieira Ferro
- Laboratório de Imunofisiologia da Reprodução, Instituto de Ciências Biomédicas, Universidade Federal de Uberlândia, Av. Pará, 1720, Building: 2B, CEP, Uberlândia, 38405-320, Brazil.
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Human toxoplasmosis: a systematic review for genetic diversity of Toxoplasma gondii in clinical samples. Epidemiol Infect 2018; 147:e36. [PMID: 30394261 PMCID: PMC6518561 DOI: 10.1017/s0950268818002947] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Toxoplasma gondii (T. gondii) as an obligate intracellular protozoan with a worldwide distribution can infect virtually all warm-blooded animals and humans. This study aims to provide a summary of the available data on genotypes of T. gondii in human. Five databases including MEDLINE in PubMed, Scopus, Science Direct, Web of Science and Google Scholar were searched for the T. gondii genotyping in human during 1995-August 2017. Next, we screened all the articles based on the inclusion and exclusion criteria. Overall, 26 studies were eligible regarding genotyping T. gondii in human samples. In clonal genotyping, 167 out of 286 cases (58%) were infected with type II. Genetic characterisation of T. gondii isolates displayed that type II was the most predominant genotype in human with the prevalence of 64.3%, 62.1% and 41.7% in patients with AIDS, congenital and ocular toxoplasmosis, respectively. In ToxoDB genotyping, most individuals were infected with genotypes #9 and #65 (21.2%). Based on these results, genotype profile of T. gondii isolates is different throughout the world. The strains in Asian and African countries are characterised by low genetic diversity, while in North and South America a wide diversity of this parasite is found. In countries without any data (e.g. Australia, Western and Southern Africa and Western Asia), identification of T. gondii genotypes might discover higher genetic diversity.
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Pardini L, Bernstein M, Carral LA, Kaufer FJ, Dellarupe A, Gos ML, Campero LM, Moré G, Messina MT, Schneider MV, Freuler CB, Durlach RA, Unzaga JM, Venturini MC. Congenital human toxoplasmosis caused by non-clonal Toxoplasma gondii genotypes in Argentina. Parasitol Int 2018; 68:48-52. [PMID: 30304711 DOI: 10.1016/j.parint.2018.10.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2018] [Revised: 10/01/2018] [Accepted: 10/05/2018] [Indexed: 11/29/2022]
Abstract
Toxoplasmosis, a worldwide distributed zoonosis, can be transmitted congenitally affecting fetuses and developing variable clinical signs. Different Toxoplasma gondii genotypes and infective dose are related factors with different clinical manifestations. Several studies indicate that atypical strains could produce more severe clinical manifestations compared to typical strains. Umbilical cord blood (n = 37) and placenta (n = 19) were collected at birth from women with acute T. gondii infection and processed for isolation by mice bioassay. Six isolates were obtained and identified as TgHm14-4Arg, TgHm15-02Arg, TgHm16-01Arg, TgHm16-02Arg, TgHm17-01Arg and TgHm17-02Arg. Three genotypes described previously on Toxo-DB were identified: #138 identified in chickens from Brazil, #182 isolated from eared doves from Brazil, #14 from wallaby kangaroos and chickens from Argentina, chickens from Brazil, Colombia, Chile and Venezuela, cats and dogs from Brazil and Colombia and also coyotes from USA indicating worldwide distribution of these genotypes. Two new allele combinations were obtained showing high genotypes diversity in Argentina. Four of the isolates (TgHm14-4Arg, TgHm15-02Arg, TgHm16-01Arg, TgHm16-02Arg) and two of them (TgHm17-01Arg, TgHm17-02Arg) produced chronic and acute infections in mice, respectively. Until now, seven T. gondii isolates have been obtained from humans in Argentina, and all were atypical or non-clonal genotypes. The identification of atypical strains causing congenital toxoplasmosis and circulating in our region, make important to perform the serological screenings according Argentine Consensus of Toxoplasmosis and to apply and monitoring treatments earlier in pregnancy. To achieve this aim, it is necessary to inform general population about T. gondii infection, diagnostics and control measures. These results should serve to generate awareness about congenital toxoplasmosis in South America.
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Affiliation(s)
- Lais Pardini
- Laboratorio de Inmunoparasitología, FCV-UNLP, La Plata, Argentina; CONICET, Argentina.
| | - Mariana Bernstein
- Laboratorio de Inmunoparasitología, FCV-UNLP, La Plata, Argentina; CONICET, Argentina
| | - Liliana A Carral
- Centro de Toxoplasmosis, Hospital Alemán, Buenos Aires, Argentina
| | | | - Andrea Dellarupe
- Laboratorio de Inmunoparasitología, FCV-UNLP, La Plata, Argentina; CONICET, Argentina
| | - María L Gos
- Laboratorio de Inmunoparasitología, FCV-UNLP, La Plata, Argentina; CONICET, Argentina
| | - Lucía M Campero
- Laboratorio de Inmunoparasitología, FCV-UNLP, La Plata, Argentina; CONICET, Argentina
| | - Gastón Moré
- Laboratorio de Inmunoparasitología, FCV-UNLP, La Plata, Argentina; CONICET, Argentina
| | - Matías T Messina
- Centro de Toxoplasmosis, Hospital Alemán, Buenos Aires, Argentina
| | | | | | | | - Juan M Unzaga
- Laboratorio de Inmunoparasitología, FCV-UNLP, La Plata, Argentina
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Vergara A, Marangi M, Caradonna T, Pennisi L, Paludi D, Papini R, Ianieri A, Giangaspero A, Normanno G. Toxoplasma gondii Lineages Circulating in Slaughtered Industrial Pigs and Potential Risk for Consumers. J Food Prot 2018; 81:1373-1378. [PMID: 30019961 DOI: 10.4315/0362-028x.jfp-17-496] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Toxoplasma gondii is a cosmopolitan zoonotic protozoan parasite, and the consumption of raw or undercooked pig meat is one of the most important sources of T. gondii infection. Three predominant lineages, types I, II, and III, are widespread in Europe. Although still poorly understood, a relationship between each type and the severity of illness represents a public health issue. To gain further knowledge of the genotypes in circulation and of the potential risk for consumers, one heart sample and one diaphragm sample (206 total) were taken from each of 103 pig carcasses at an abattoir in Italy. Then, we used 529-bp repetitive element PCR and a B1 real-time PCR high-resolution melting assay coupled with sequencing to detect and genotype T. gondii isolates. T. gondii DNA was detected in 14 pigs (13.6%, 95% confidence interval = 7 to 20.2%), and types I (3.9%), II (5.8%), and III (3.9%) were identified. We found that heart tissue had a significantly higher PCR positivity rate for T. gondii than did diaphragm tissue. This is Europe's largest study on genotyping of T. gondii from pigs, and it demonstrates that all three main lineages are present in carcasses of industrially reared pigs in Italy. There is a potential risk to consumers of infection with any or all of the three lineages, and the related clinical consequences should be taken into account. This study suggests that monitoring of T. gondii types in meat is essential, especially in meat that is traditionally eaten raw or that is minimally processed.
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Affiliation(s)
- Alberto Vergara
- 1 Faculty of Veterinary Medicine, University of Teramo, 64100 Teramo, Italy
| | - Marianna Marangi
- 2 Department of the Science of Agriculture, Food and Environment, University of Foggia, 71121 Foggia, Italy
| | - Tiziana Caradonna
- 2 Department of the Science of Agriculture, Food and Environment, University of Foggia, 71121 Foggia, Italy
| | - Luca Pennisi
- 1 Faculty of Veterinary Medicine, University of Teramo, 64100 Teramo, Italy
| | - Domenico Paludi
- 1 Faculty of Veterinary Medicine, University of Teramo, 64100 Teramo, Italy
| | - Roberto Papini
- 3 Department of Veterinary Science, University of Pisa, 56126 Pisa, Italy; and
| | - Adriana Ianieri
- 4 Department of Food and Drug, University of Parma, 43124 Parma, Italy
| | - Annunziata Giangaspero
- 2 Department of the Science of Agriculture, Food and Environment, University of Foggia, 71121 Foggia, Italy
| | - Giovanni Normanno
- 2 Department of the Science of Agriculture, Food and Environment, University of Foggia, 71121 Foggia, Italy
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Wang C, Cheng W, Yu Q, Xing T, Chen S, Liu L, Yu L, Du J, Luo Q, Shen J, Xu Y. Toxoplasma Chinese 1 Strain of WH3Δ rop16I/III / gra15II Genetic Background Contributes to Abnormal Pregnant Outcomes in Murine Model. Front Immunol 2018; 9:1222. [PMID: 29910815 PMCID: PMC5992278 DOI: 10.3389/fimmu.2018.01222] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2018] [Accepted: 05/15/2018] [Indexed: 12/31/2022] Open
Abstract
Toxoplasma gondii infection evokes a strong Th1-type response with interleukin (IL)-12 and interferon (IFN)-γ secretion. Recent studies suggest that the infection of pregnant mice with T. gondii may lead to adverse pregnancy results caused by subversion of physiological immune tolerance at maternofetal interface rather than direct invasion of the parasite. Genotype-associated dense granule protein GRA15II tends to induce classically activated macrophage (M1) differentiation and subsequently activating NK, Th1, and Th17 cells whereas rhoptry protein ROP16I/III drives macrophages to alternatively activated macrophage (M2) polarization and elicits Th2 immune response. Unlike the archetypal strains of types I, II, and III, type Chinese 1 strains possess both GRA15II and ROP16I/III, suggesting a distinct pathogenesis of Toxoplasma-involved adverse pregnancies. We constructed T. gondii type Chinese 1 strain of WH3Δrop16 based on CRISPR/Cas9 technology to explore the ROP16I/III-deficient/GRA15II-dominant parasites in induction of trophoblast apoptosis in vitro and abnormal pregnant outcomes of mice in vivo. Our study showed that Toxoplasma WH3Δrop16 remarkably induced apoptosis of trophoblasts. C57BL/6 pregnant mice injected with the tachyzoites of WH3Δrop16 presented increased absorptivity of fetuses in comparison with the mice infected with WH3 wild type (WH3 WT) parasites although no remarkable difference of virulence to mice was seen between the two strains. Additionally, the mice inoculated with WH3Δrop16 tachyzoites exhibited a notable expression of both IL-17A and IFN-γ, while the percentage of CD4+CD25+FoxP3 [T regulatory cells (Tregs)] were diminished in splenocytes and placenta tissues compared to those infected with WH3 WT parasites. Accordingly, expressions of IL-4, IL-10, and transforming growth factor beta 1, the pivotal cytokines of Th2 and Tregs response, were significantly dampened whereas IFN-γ and IL-12 expressions were upregulated in WH3Δrop16-infected mice, which gave rise to more prominent outcomes of abnormal pregnancies. Our results indicated that the WH3Δrop16 parasites with gra15II background of T. gondii type Chinese 1 strains may cause miscarriage and stillbirth due to subversion of the maternal immune tolerance and system immunity of the animals and the GRA15II effector contributes to the process of adverse pregnant consequences.
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Affiliation(s)
- Cong Wang
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Weisheng Cheng
- Department of Medical Genetics, Zhongshan School of Medicine, Sun Yat-sen University, The Key Laboratory of Tropical Disease Control, Ministry of Education, Guangzhou, China
| | - Qian Yu
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Tian Xing
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Shoubin Chen
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Lei Liu
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Li Yu
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Jian Du
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Qingli Luo
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
| | - Jilong Shen
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
- Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Yuanhong Xu
- Department of Pathogen Biology, Provincial Laboratories of Pathogen Biology and Zoonoses, School of Basic Medicine, Anhui Medical University, Hefei, China
- Department of Clinical Laboratory, The First Affiliated Hospital of Anhui Medical University, Hefei, China
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Rico-Torres CP, Valenzuela-Moreno LF, Luna-Pastén H, Figueroa-Damián R, Gómez-Toscano V, Hernández-Delgado L, Escobedo-Torres MP, Correa D. High heterogeneity, mixed infections and new genotypes in human congenital toxoplasmosis cases in the mega-metropolis of Central Mexico. Acta Trop 2018; 178:124-129. [PMID: 29170005 DOI: 10.1016/j.actatropica.2017.11.008] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2017] [Revised: 11/07/2017] [Accepted: 11/17/2017] [Indexed: 10/18/2022]
Abstract
Mexico presents high prevalence of Toxoplasma gondii infection, including the congenital form, but there are few data about the genetic diversity of the parasite, so we attempted parasite isolation and genotyping in nine mother/children pairs with congenital toxoplasmosis (CT), living in the Valley of Mexico, who were part of a 30 cases cohort that started 12 years ago. They were recruited through research projects which included pre- and postnatal screening of congenital infections or directly CT, and cases referred to INP for management because they had clinical abnormalities. Genotyping was performed by PCR-RFLP of SAG1, SAG2, SAG3, BTUB GRA6, c22-8, c29-2, L358, PK1 and Apico markers, followed by sequencing. Sixty seven percent of samples were typed for the SAG3 locus, 39% for Apico and 33% for BTUB, while Alt. SAG2, GRA6 and c29-2 types could be labelled in less cases. Type I alleles predominated, followed by II and III. We isolated the first strain obtained from humans in Mexico and found three genotypes not previously found in the world. The presence of ToxoDB#10 clonal type was documented in one pair, as well as mixed infections in five mothers. No relation of genotype or parasite load with clinical signs was found. In conclusion, we encountered great genetic diversity and mixed T. gondii infections among mother/children pairs with congenital toxoplasmosis in the mega-metropolis of the Valley of Mexico.
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