1
|
Pollak A. 40 years neonatology : An academic life. Wien Klin Wochenschr 2024:10.1007/s00508-024-02360-2. [PMID: 38634910 DOI: 10.1007/s00508-024-02360-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2024] [Indexed: 04/19/2024]
Abstract
BACKGROUND A complete review of the development of neonatology in the last 40 years would probably require a compendium with several volumes, to bring to view the remarkable improvements in survival rates and neurodevelopmental outcomes of ill babies in Austria, most industrial countries and to some extent worldwide. The challenge I had to solve here was to integrate my own contributions to the field of neonatology during this period and particularly the contributions of my team from the Division of Neonatology and Pediatric Intensive Care Medicine, Department of Pediatrics and Adolescence Medicine, Medical University Vienna where I was working first as an intern and resident and later had the privilege to become head of department. AIM This very personal review was conceived to showcase the milestones of neonatology where, in my opinion, our department made some meaningful contributions in research and clinical practice during the past 40 years. METHODS A total of 10 areas of interest were selected which most likely influenced survival rates of preterm infants born at increasingly younger gestational ages and ameliorated long-term clinical and neurodevelopmental outcomes, including: 1) Construction and continuous modernization of neonatal intensive care units (NICUs). 2) Installation of the "Regionalization Program for NICUs in Vienna". 3) Treatment of respiratory distress syndrome (RDS) of premature babies. 4) Fine tuning of glucose metabolism for growth and outcome. 5) Neurodevelopmental care. 6) Neonatal hematology. 7) Infection control. 8) The toxoplasma screening program. 9) The newborn screening program. 10) Quality control: the Vermont Oxford Neonatal Network (VONN). RESULTS Over the past four decades advancements in research and technology have allowed a transformative development of neonatal medicine. Survival rates without increased morbidity for very premature infants with gestational ages reaching to what we consider nowadays the border of viability have constantly increased. In my professional life as a neonatologist in Austria I have had the possibility to support and shape some of these developments together with my team. CONCLUSION As we look ahead it is imperative to build upon the progress made, harnessing the power of science and technology to further improve the survival and quality of life for preterm infants in Austria and worldwide. At the same time, neonatology must continue to prioritize ethical reflection and education, fostering a culture of integrity, interdisciplinary collaboration, and the development of guidelines and protocols that uphold ethical standards while addressing the evolving needs and complexities of neonatal medicine.
Collapse
Affiliation(s)
- Arnold Pollak
- Department of Pediatrics and Adolescent Medicine, Division of Neonatology, Pediatric Intensive Care Medicine and Neuropediatrics, Medical University of Vienna, Vienna, Austria.
| |
Collapse
|
2
|
Prasil P, Sleha R, Kacerovsky M, Bostik P. Comparison of adverse reactions of spiramycin versus pyrimethamine/sulfadiazine treatment of toxoplasmosis in pregnancy: is spiramycin really the drug of choice for unproven infection of the fetus? J Matern Fetal Neonatal Med 2023; 36:2215377. [PMID: 37217458 DOI: 10.1080/14767058.2023.2215377] [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: 01/18/2023] [Revised: 05/13/2023] [Accepted: 05/13/2023] [Indexed: 05/24/2023]
Abstract
BACKGROUND Therapeutic regimens for the treatment of toxoplasmosis are not standardized. Treatment strategy mainly at the end of the second and the beginning of the third trimester, especially in cases of negative prenatal diagnosis, is the least uniform. In some situations, the choice of treatment may be ambiguous, and adverse drug reactions of the therapy should be taken into consideration. METHODS Adverse drug reactions of anti-toxoplasma therapy with spiramycin (n = 77) versus pyrimethamine/sulfadiazine (n = 35) were compared in 112 pregnant women. RESULTS Up to 36.6% of women reported adverse reactions to the treatment overall (n = 41). Out of those 38.9% (n = 30) were treated with spiramycin and 31.4% (n = 11) with pyrimethamine/sulfadiazine. Toxic allergic reactions were the only indication for discontinuation of treatment in 8.9% of patients (n = 10), where 9.1% (n = 7) were reported in spiramycin and 8.6% (n = 3) in pyrimethamine/sulfadiazine cohort. Neurotoxic complications (acral paraesthesia) were significantly more frequent during the therapy with spiramycine in 19.5% (n = 15) compared to no cases in pyrimethamine/sulfadiazine group (p = .003). Other adverse drug reactions, such as gastrointestinal discomfort, nephrotoxicity, vaginal discomfort were reported, but the differences between the cohorts were not significant. CONCLUSIONS The superiority of one of the therapeutic regimens was not statistically demonstrated, since the differences in overall toxicity or incidence of toxic allergic reactions between the cohorts were not confirmed (p = .53 and p = 1.00, respectively). However, although the isolated neurotoxicity of spiramycin was the only significant adverse reaction demonstrated in this study, pyrimethamine/sulfadiazine therapy should be preferred, because it is known to be more effective and with limited adverse reactions.
Collapse
Affiliation(s)
- Petr Prasil
- Department of Infectious Diseases, Charles University, Faculty of Medicine and University Hospital, Hradec Kralove, Czech Republic
| | - Radek Sleha
- Department of Epidemiology, University of Defence, Faculty of Military Health Sciences, Hradec Kralove, Czech Republic
| | - Marian Kacerovsky
- Department of Obstetrics and Gynecology, Charles University, Faculty of Medicine and University Hospital, Hradec Kralove, Czech Republic
| | - Pavel Bostik
- Institute of Clinical Microbiology, Charles University, Faculty of Medicine and University Hospital, Hradec Kralove, Czech Republic
| |
Collapse
|
3
|
Rahimi HM, Nemati S, Alavifard H, Baghaei K, Mirjalali H, Zali MR. Soluble total antigen derived from Toxoplasma gondii RH strain prevents apoptosis, but induces anti-apoptosis in human monocyte cell line. Folia Parasitol (Praha) 2021; 68. [PMID: 34889779 DOI: 10.14411/fp.2021.026] [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: 04/24/2021] [Accepted: 08/24/2021] [Indexed: 11/19/2022]
Abstract
Apoptosis plays crucial role in the pathogenesis of toxoplasmosis, as it limits further development of the disease. The current study aimed to investigate the effects of different concentrations of soluble total antigen (STAg) of Toxoplasma gondii (Nicolle et Manceaux, 1908) on the apoptotic and anti-apoptotic pathways. PMA-activated THP-1 cell line was sensed by T. gondii STAg and the expression patterns of caspase-3, -7, -8, -9, Bax, Bcl-2, and Mcl-1 genes were evaluated. The results showed statistically significant concentration-dependent overexpression of both Bcl-2 (P-value < 0.0001) and Mcl-1 (P-value = 0.0147). The cas-7 showed overexpression in all concentrations (P-value < 0.0001). The cas-3 was suppressed in concentrations 100, 80, and 40 µg, but statistically significant downregulated in concentrations 10 and 20 µg. The Bax was suppressed in concentrations 100 to 20 µg, while it slightly downregulated 1.42 fold (P-value = 0.0029) in concentration 10 µg. The expression of cas-8 and -9 was suppressed in all concentrations. Our results indicated that T. gondii STAg downregulated and suppressed apoptotic and upregulated anti-apoptotic pathways. The upregulation of cas-7 in this study may indicate the role of T. gondii STAg in activation of inflammatory responses.
Collapse
Affiliation(s)
- Hanieh Mohammad Rahimi
- Foodborne and Waterborne Diseases Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Sara Nemati
- Foodborne and Waterborne Diseases Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Helia Alavifard
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Kaveh Baghaei
- Basic and Molecular Epidemiology of Gastrointestinal Disorders Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Hamed Mirjalali
- Foodborne and Waterborne Diseases Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran
| | - Mohammad Reza Zali
- Gastroenterology and Liver Diseases Research Centre, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Tehran, Iran *Address for correspondence: Hamed Mirjalali, Foodborne and Waterborne Diseases Research Center, Research Institute for Gastroenterology and Liver Diseases, Shahid Beheshti University of Medical Sciences, Arabi Street, 1985717413, Chamran Highway, Tehran, Iran.
| |
Collapse
|
4
|
Zhu L, Lei Z, Xia X, Zhang Y, Chen Y, Wang B, Li J, Li G, Yang G, Cao G, Yin Z. Yeast Shells Encapsulating Adjuvant AS04 as an Antigen Delivery System for a Novel Vaccine against Toxoplasma Gondii. ACS APPLIED MATERIALS & INTERFACES 2021; 13:40415-40428. [PMID: 34470103 DOI: 10.1021/acsami.1c12366] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/13/2023]
Abstract
Toxoplasma gondii (T. gondii) infection causes severe zoonotic toxoplasmosis, which threatens the safety of almost one-third of the human population globally. However, there is no effective protective vaccine against human toxoplasmosis. This necessitates anti-T. gondii vaccine development, which is a main priority of public health. In this study, we optimized the adjuvant system 04 (AS04), a vaccine adjuvant constituted by 3-O-desacyl-4'-monophosphoryl lipid A (a TLR4 agonist) and aluminum salts, by packing it within natural extracts of β-glucan particles (GPs) from Saccharomyces cerevisiae to form a GP-AS04 hybrid adjuvant system. Through a simple mixing procedure, we loaded GP-AS04 particles with the total extract (TE) of T. gondii lysate, forming a novel anti-T. gondii vaccine GP-AS04-TE. Results indicated that the hybrid adjuvant can efficiently and stably load antigens, mediate antigen delivery, facilitate the dendritic uptake of antigens, boost dendritic cell maturation and stimulation, and increase the secretion of pro-inflammatory cytokines. In the mouse inoculation model, GP-AS04-TE significantly stimulated the function of dendritic cells, induced a very strong TE-specific humoral and cellular immune response, and finally showed a strong and effective protection against toxoplasma chronic and acute infections. This work proves the potential of GP-AS04 for exploitation as a vaccine against a range of pathogens.
Collapse
Affiliation(s)
- Leqing Zhu
- The First Affiliated Hospital, Faculty of Medical Science, Jinan University, Guangzhou 510632, China
- The Biomedical Translational Research Institute, Faculty of Medical Science, Jinan University, Guangzhou 510632, China
| | - Zhiwei Lei
- Guangdong Provincial Key Laboratory of Virology, Institute of Medical Microbiology, Jinan University, Guangzhou 510632, China
- The Sixth Affiliated Hospital of Guangzhou Medical University, Qingyuan People's Hospital, Qingyuan 511518, China
| | - Xichun Xia
- Zhuhai Institute of Translational Medicine, Zhuhai People's Hospital (Zhuhai Hospital Affiliated with Jinan University), Jinan University, Zhuhai 51900, China
- The Biomedical Translational Research Institute, Faculty of Medical Science, Jinan University, Guangzhou 510632, China
| | - Yingying Zhang
- The Biomedical Translational Research Institute, Faculty of Medical Science, Jinan University, Guangzhou 510632, China
| | - Yuyuan Chen
- The Biomedical Translational Research Institute, Faculty of Medical Science, Jinan University, Guangzhou 510632, China
| | - Baocheng Wang
- Tsinghua-Berkeley Shenzhen Institute, Tsinghua University, Shenzhen 518055, China
| | - Jiawei Li
- Zhuhai Institute of Translational Medicine, Zhuhai People's Hospital (Zhuhai Hospital Affiliated with Jinan University), Jinan University, Zhuhai 51900, China
- The Biomedical Translational Research Institute, Faculty of Medical Science, Jinan University, Guangzhou 510632, China
| | - Guangqiang Li
- The First Affiliated Hospital, Faculty of Medical Science, Jinan University, Guangzhou 510632, China
| | - Guang Yang
- Department of Pathogen Biology, School of Medicine, Jinan University, Guangzhou 510632, China
| | - Guangchao Cao
- Zhuhai Institute of Translational Medicine, Zhuhai People's Hospital (Zhuhai Hospital Affiliated with Jinan University), Jinan University, Zhuhai 51900, China
- The Biomedical Translational Research Institute, Faculty of Medical Science, Jinan University, Guangzhou 510632, China
| | - Zhinan Yin
- Zhuhai Institute of Translational Medicine, Zhuhai People's Hospital (Zhuhai Hospital Affiliated with Jinan University), Jinan University, Zhuhai 51900, China
- The Biomedical Translational Research Institute, Faculty of Medical Science, Jinan University, Guangzhou 510632, China
| |
Collapse
|
5
|
RHΔ gra17Δ npt1 Strain of Toxoplasma gondii Elicits Protective Immunity Against Acute, Chronic and Congenital Toxoplasmosis in Mice. Microorganisms 2020; 8:microorganisms8030352. [PMID: 32121619 PMCID: PMC7142655 DOI: 10.3390/microorganisms8030352] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2020] [Revised: 02/13/2020] [Accepted: 02/26/2020] [Indexed: 12/19/2022] Open
Abstract
: In the present study, a dense granule protein 17 (gra17) and novel putative transporter (npt1) double deletion mutant of Toxoplasma gondii RH strain was engineered. The protective efficacy of vaccination using RHΔgra17Δnpt1 tachyzoites against acute, chronic, and congenital toxoplasmosis was studied in a mouse model. Immunization using RHΔgra17Δnpt1 induced a strong humoral and cellular response, as indicated by the increased levels of anti-T. gondii specific IgG, interleukin 2 (IL-2), IL-10, IL-12, and interferon-gamma (IFN-γ). Vaccinated mice were protected against a lethal challenge dose (103 tachyzoites) of wild-type homologous (RH) strain and heterologous (PYS and TgC7) strains, as well as against 100 tissue cysts or oocysts of Pru strain. Vaccination also conferred protection against chronic infection with 10 tissue cysts or oocysts of Pru strain, where the numbers of brain cysts in the vaccinated mice were significantly reduced compared to those detected in the control (unvaccinated + infected) mice. In addition, vaccination protected against congenital infection with 10 T. gondii Pru oocysts (administered orally on day 5 of gestation) as shown by the increased litter size, survival rate and the bodyweight of pups born to vaccinated dams compared to those born to unvaccinated + infected dams. The brain cyst burden of vaccinated dams was significantly lower than that of unvaccinated dams infected with oocysts. Our data show that T. gondii RHΔgra17Δnpt1 mutant strain can protect mice against acute, chronic, and congenital toxoplasmosis by balancing inflammatory response with immunogenicity.
Collapse
|
6
|
Wang JL, Li TT, Elsheikha HM, Chen K, Cong W, Yang WB, Bai MJ, Huang SY, Zhu XQ. Live Attenuated Pru:Δcdpk2 Strain of Toxoplasma gondii Protects Against Acute, Chronic, and Congenital Toxoplasmosis. J Infect Dis 2019; 218:768-777. [PMID: 29669003 DOI: 10.1093/infdis/jiy211] [Citation(s) in RCA: 35] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2018] [Accepted: 04/11/2018] [Indexed: 11/14/2022] Open
Abstract
Background The threat of Toxoplasma gondii infection in immunocompromised individuals and pregnant women necessitates the development of a safe and effective vaccine. Here, we examined the immune protection conferred by a live attenuated strain of T. gondii. Methods We tested the efficacy of intraperitoneal vaccination using 500 Ca2+-dependent protein kinase 2 (cdpk2)-deficient tachyzoites of T. gondii Pru strain against acute, chronic, and congenital toxoplasmosis in mice. The kinetics of antibody response, cytokines, and other quantifiable correlates of protection against T. gondii infection were determined. Results Vaccination with Pru:Δcdpk2 induced a high level of anti-T. gondii immunoglobulin G titer, type 1 T-helper (Th1) response at 28 days postvaccination, and a mixed Th1/type 2 T-helper response at 70 days postvaccination. All vaccinated mice survived a heterologous challenge with 1000 tachyzoites of RH or ToxoDB#9 (PYS or TgC7) strains. Also, vaccination protected against homologous infection with 20 T. gondii Pru cysts, and improved pregnancy outcome by reducing parasite cyst load in the brain, maintaining litter size and body weight of pups born to vaccinated dams challenged with 10 Pru cysts compared to pups born to unvaccinated dams. Conclusions The use of T. gondii Pru:Δcdpk2 mutant strain represents a promising approach to protection against acute, chronic, and congenital toxoplasmosis in mice.
Collapse
Affiliation(s)
- 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, 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, People's Republic of China
| | - Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Loughborough, United Kingdom
| | - Kai Chen
- 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, People's Republic of China
| | - Wei Cong
- College of Marine Science, Shandong University at Weihai, Weihai, Shandong Province, People's Republic of China
| | - Wen-Bin Yang
- 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, People's Republic of China.,College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi Province, People's Republic of China
| | - Meng-Jie Bai
- 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, People's Republic of China
| | - Si-Yang Huang
- 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, People's Republic of China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu Province, 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, People's Republic of China.,Jiangsu Co-innovation Center for Prevention and Control of Important Animal Infectious Diseases and Zoonoses, Yangzhou, Jiangsu Province, People's Republic of China
| |
Collapse
|
7
|
Yang WB, Wang JL, Gui Q, Zou Y, Chen K, Liu Q, Liang QL, Zhu XQ, Zhou DH. Immunization With a Live-Attenuated RH:Δ NPT1 Strain of Toxoplasma gondii Induces Strong Protective Immunity Against Toxoplasmosis in Mice. Front Microbiol 2019; 10:1875. [PMID: 31456786 PMCID: PMC6701201 DOI: 10.3389/fmicb.2019.01875] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Accepted: 07/29/2019] [Indexed: 12/14/2022] Open
Abstract
Toxoplasmosis, one of the most important health-threatening diseases worldwide, is caused by Toxoplasma gondii, which infects a wide range of warm-blooded animals and humans, leading to enormous health and socioeconomic concerns. T. gondii can establish chronic infection to evade the immune response in hosts. Once a chronic infection has been established, the available treatments cannot efficiently control this stage of T. gondii efficiently. Moreover, the available treatments rely only on a few drugs, such as sulfapyridine and pyrimethamine, that tend to have severe side effects. Given these factors, vaccination has been considered to be the most efficient method to prevent and control this disease. However, there is currently lack of effective vaccine available for use to prevent toxoplasmosis apart form Toxovax®, the only available vaccine, which is used in sheep to prevent abortion. To address this problem, we knocked out the NPT1 gene of the type I T. gondii strain using the CRISPR-Cas9 system, constructed a live-attenuated vaccine and evaluated its protective efficacy in a mouse model. Immunization of mice with RH:ΔNPT1 induced a high level of Toxoplasma-specific IgG1, IgG2a and total IgG 42 days after immunization. There was a significant increase in the levels of cytokines in the splenocyte suspensions of RH:ΔNPT1-infected mice, and a mixed Th1/Th2 response was induced in the mice. Remarkably, after heterologous challenges with tachyzoites of the RH, PYS and Pru strains and cysts of the Pru strain by different infection routes, the immunized animals were protected from toxoplasmosis with a 100% survival rate, in both acute and chronic infection. In addition, compared with control mice, the Pru cyst load was clearly reduced in the brains of RH:ΔNPT1-infected immunization-mice. Our study demonstrated that the RH:ΔNPT1 strain was able to evoke strong anti-Toxoplasma immune responses and provide effective protection against parasite strains with different levels of virulence, suggesting that the RH:ΔNPT1 strain may represent a promising live-attenuated vaccine against toxoplasmosis, which is worthy of further evaluation in food-producing animals and in definitive feline host.
Collapse
Affiliation(s)
- Wen-Bin Yang
- Key Laboratory of Fujian-Taiwan Animal Pathogen Biology, College of Animal Sciences, Fujian Agriculture and Forestry University, Fuzhou, China.,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.,Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai, 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
| | - Qian Gui
- Department of Microbiology and Microbial Engineering, School of Life Sciences, Fudan University, Shanghai, China
| | - Yang Zou
- 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
| | - Kai Chen
- 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
| | - Qing Liu
- College of Animal Science and Veterinary Medicine, Shanxi Agricultural University, Taigu, 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
| | - 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.,Jiangsu Co-innovation Center for the Prevention and Control of Important Animal Infectious Diseases and Zoonoses, College of Veterinary Medicine, Yangzhou University, Yangzhou, China
| | - Dong-Hui Zhou
- Key Laboratory of Fujian-Taiwan Animal Pathogen Biology, College of Animal Sciences, Fujian Agriculture and Forestry University, Fuzhou, China
| |
Collapse
|
8
|
Liu K, Wen H, Cai H, Wu M, An R, Chu D, Yu L, Shen J, Chen L, Du J. Protective Effect Against Toxoplasmosis in BALB/c Mice Vaccinated With Toxoplasma gondii Macrophage Migration Inhibitory Factor. Front Microbiol 2019; 10:813. [PMID: 31105655 PMCID: PMC6491892 DOI: 10.3389/fmicb.2019.00813] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2018] [Accepted: 04/01/2019] [Indexed: 01/02/2023] Open
Abstract
Toxoplasma gondii is an obligate intracellular parasite responsible for toxoplasmosis, which can cause severe disease in the fetus and immunocompromised individuals. Developing an effective vaccine is crucial to control this disease. Macrophage migration inhibitory factor (MIF) has gained substantial attention as a pivotal upstream cytokine to mediate innate and adaptive immune responses. Homologs of MIF have been discovered in many parasitic species, and one homolog of MIF has been isolated from the parasite Toxoplasma gondii. In this study, the recombinant Toxoplasma gondii MIF (rTgMIF) as a protein vaccine was expressed and evaluated by intramuscular injection in BALB/c mice. We divided the mice into different dose groups of vaccines, and all immunizations with purified rTgMIF protein were performed at 0, 2, and 4 weeks. The protective efficacy of vaccination was analyzed by antibody assays, cytokine measurements and lymphoproliferative assays, respectively. The results obtained indicated that the rTgMIF vaccine elicited strong humoral and cellular immune responses with high levels of IgG antibody and IFN-γ production compared to those of the controls, in addition to slight higher levels of IL-4 production. After vaccination, a stronger lymphoproliferative response was also noted. Additionally, the survival time of mice immunized with rTgMIF was longer than that of the mice in control groups after challenge infection with virulent T. gondii RH tachyzoites. Moreover, the number of brain tissue cysts in vaccinated mice was reduced by 62.26% compared with the control group. These findings demonstrated that recombinant TgMIF protein is a potential candidate for vaccine development against toxoplasmosis.
Collapse
Affiliation(s)
- Kang Liu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Anhui Provincial Key Laboratory of Microbiology and Parasitology, Anhui Medical University, Hefei, China
| | - Hongyang Wen
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Anhui Provincial Key Laboratory of Microbiology and Parasitology, Anhui Medical University, Hefei, China
| | - Haijian Cai
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Anhui Provincial Key Laboratory of Microbiology and Parasitology, Anhui Medical University, Hefei, China
| | - Minmin Wu
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Anhui Provincial Key Laboratory of Microbiology and Parasitology, Anhui Medical University, Hefei, China
| | - Ran An
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Anhui Provincial Key Laboratory of Microbiology and Parasitology, Anhui Medical University, Hefei, China
| | - Deyong Chu
- Anhui Provincial Key Laboratory of Microbiology and Parasitology, Anhui Medical University, Hefei, China
| | - Li Yu
- Anhui Provincial Key Laboratory of Microbiology and Parasitology, Anhui Medical University, Hefei, China
| | - Jilong Shen
- Anhui Provincial Key Laboratory of Microbiology and Parasitology, Anhui Medical University, Hefei, China
| | - Lijian Chen
- Department of Anesthesiology, The First Affiliated Hospital of Anhui Medical University, Hefei, China
| | - Jian Du
- Department of Biochemistry and Molecular Biology, School of Basic Medical Sciences, Anhui Medical University, Hefei, China.,Anhui Provincial Key Laboratory of Microbiology and Parasitology, Anhui Medical University, Hefei, China
| |
Collapse
|
9
|
Xia N, Zhou T, Liang X, Ye S, Zhao P, Yang J, Zhou Y, Zhao J, Shen B. A Lactate Fermentation Mutant of Toxoplasma Stimulates Protective Immunity Against Acute and Chronic Toxoplasmosis. Front Immunol 2018; 9:1814. [PMID: 30147689 PMCID: PMC6096001 DOI: 10.3389/fimmu.2018.01814] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2018] [Accepted: 07/23/2018] [Indexed: 12/20/2022] Open
Abstract
Toxoplasma gondii is an important zoonotic pathogen infecting one-third of the world’s population and numerous animals, causing significant healthcare burden and socioeconomic problems. Vaccination is an efficient way to reduce global sero-prevalence, however, ideal vaccines are not yet available. We recently discovered that the Toxoplasma mutant lacking both lactate dehydrogenases LDH1 and LDH2 (Δldh) grew well in vitro but was unable to propagate in mice, making it a good live vaccine candidate. Here, we tested the protection efficacy of ME49 Δldh using a mouse model. Vaccinated mice were efficiently protected from the lethal challenge of a variety of wild-type strains, including type 1 strain RH, type 2 strain ME49, type 3 strain VEG, and a field isolate of Chinese 1. The protection efficacies of a single vaccination were nearly 100% for most cases and it worked well against the challenges of both tachyzoites and tissue cysts. Re-challenging parasites were unable to propagate in vaccinated mice, nor did they make tissue cysts. High levels of Toxoplasma-specific IgG were produced 30 days after immunization and stayed high during the whole tests (at least 125 days). However, passive immunization of naïve mice with sera from vaccinated mice did reduce parasite propagation, but the overall protection against parasite infections was rather limited. On the other hand, Δldh immunization evoked elevated levels of Th1 cytokines like INF-γ and IL-12, at early time points. In addition, splenocytes extracted from immunized mice were able to induce quick and robust INF-γ and other pro-inflammatory cytokine production upon T. gondii antigen stimulation. Together these results suggest that cellular immune responses are the main contributors to the protective immunity elicited by Δldh vaccination, and humoral immunity also contributes partially. We also generated uracil auxotrophic mutants in ME49 and compared their immune protection efficiencies to the Δldh mutants. The results showed that these two types of mutants have similar properties as live vaccine candidates. Taken together, these results suggest that mutants lacking LDH were severely attenuated in virulence but were able to induce strong anti-toxoplasma immune responses, therefore are good candidates for live vaccines.
Collapse
Affiliation(s)
- Ningbo Xia
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Taifang Zhou
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Xiaohan Liang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Shu Ye
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Pengfei Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Jichao Yang
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Yanqin Zhou
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China
| | - Junlong Zhao
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Hubei Cooperative Innovation Center for Sustainable Pig Production, Wuhan, China.,Key Laboratory of Preventive Medicine in Hubei Province, Wuhan, China
| | - Bang Shen
- State Key Laboratory of Agricultural Microbiology, Huazhong Agricultural University, Wuhan, China.,Key Laboratory of Preventive Medicine in Hubei Province, Wuhan, China
| |
Collapse
|
10
|
Qiu J, Zhang R, Xie Y, Wang L, Ge K, Chen H, Liu X, Wu J, Wang Y. Estradiol Attenuates the Severity of Primary Toxoplasma gondii Infection-Induced Adverse Pregnancy Outcomes Through the Regulation of Tregs in a Dose-Dependent Manner. Front Immunol 2018; 9:1102. [PMID: 29868037 PMCID: PMC5968100 DOI: 10.3389/fimmu.2018.01102] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2017] [Accepted: 05/02/2018] [Indexed: 12/15/2022] Open
Abstract
Estradiol (E2) plays a crucial and intricate role during pregnancy to mediate several aspects of the pregnancy process. A perplexing phenomenon in congenital toxoplasmosis is that the severity of Toxoplasma gondii (T. gondii)-mediated adverse pregnancy outcome is closely related with time of primary maternal infection during pregnancy. In this study, the results showed that T. gondii infection in early pregnancy was more likely to induce miscarriage in mice than in late pregnancy, which may be related to inflammation of the maternal–fetal interface. Meanwhile, the T. gondii infection-induced-apoptotic rate of Tregs was higher and the expression of programmed death-1 (PD-1) on Tregs was lower in early pregnancy than in late pregnancy. As the level of E2 in mouse serum gradually increased with the development of pregnancy, we proposed that E2 may contribute to the discrepancy of Tregs at different stages of pregnancy. Thus, we investigated in vitro and in vivo effects of E2 in regulating Tregs. We found that E2 in vitro could protect Tregs against apoptosis and upregulate the expression of PD-1 on Tregs in a dose-dependent manner through ERα. Likewise, the simulated mid-pregnancy level of E2 in nonpregnant mice also alleviated the T. gondii infection-induced apoptosis of Tregs and potentiated the PD-1 expression on Tregs. Therefore, in the pathogenesis of T. gondii-induced abnormal pregnancy, E2 helped maintain the immune balance and improve the pregnancy outcome through regulating Tregs. This finding illustrates the intricate working of hormone–immune system interaction in infection-induced abnormal pregnancy.
Collapse
Affiliation(s)
- Jingfan Qiu
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Rong Zhang
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Yanci Xie
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Lijuan Wang
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Ke Ge
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, China.,Xuanwumen Community Health Service Center of Xuanwu District, Nanjing, China
| | - Hao Chen
- The First Clinical Medical College, Nanjing Medical University, Nanjing, China
| | - Xinjian Liu
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, China
| | - Jiangping Wu
- Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University, Nanjing, China
| | - Yong Wang
- Key Laboratory of Pathogen Biology of Jiangsu Province, Department of Pathogen Biology, Nanjing Medical University, Nanjing, China.,Key Laboratory of Infectious Diseases, School of Public Health, Nanjing Medical University, Nanjing, China.,State Key Laboratory of Reproductive Medicine, Nanjing Medical University, Nanjing, China
| |
Collapse
|
11
|
Holec-Gąsior L, Ferra B, Czechowska J, Serdiuk IE, Krzymiński K. A novel chemiluminescent immunoassay based on original acridinium ester labels as better solution for diagnosis of human toxoplasmosis than conventional ELISA test. Diagn Microbiol Infect Dis 2018; 91:13-19. [DOI: 10.1016/j.diagmicrobio.2017.12.022] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2017] [Revised: 12/27/2017] [Accepted: 12/28/2017] [Indexed: 11/26/2022]
|
12
|
Wang JL, Elsheikha HM, Zhu WN, Chen K, Li TT, Yue DM, Zhang XX, Huang SY, Zhu XQ. Immunization with Toxoplasma gondii GRA17 Deletion Mutant Induces Partial Protection and Survival in Challenged Mice. Front Immunol 2017; 8:730. [PMID: 28706518 PMCID: PMC5489627 DOI: 10.3389/fimmu.2017.00730] [Citation(s) in RCA: 36] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2017] [Accepted: 06/09/2017] [Indexed: 01/10/2023] Open
Abstract
Toxoplasmosis remains a world-threatening disease largely because of the lack of a fully effective vaccine. Here, we created a ΔGRA17 mutant by disrupting the virulence factor GRA17 using CRISPR-Cas9 method. Then, we tested whether ΔGRA17 tachyzoites can be used as a live-attenuated vaccine against acute, chronic, and congenital Toxoplasma gondii infection in mice. Immune response evoked by ΔGRA17 immunization suggested a sequential Th1 and Th2 T cell response, indicated by high levels of Th1 and a mixed Th1/Th2 cytokines at 28 and 70 days after immunization, respectively. ΔGRA17-mediated immunity fully protected mice against lethal infection with wild-type (wt) RH strain, heterologous challenge with PYS, and TgC7 strains of the Chinese ToxoDB#9 genotype, and T. gondii Pru strain. Although parasite cysts were detected in 8 out of 10 immunized mice, cyst burden in the brain was significantly reduced (P < 0.05) in immunized mice (53 ± 15 cysts/brain) compared to non-immunized mice (4,296 ± 687 cysts/brain). In respect to congenital infection, the litter size, survival rate, and body weight (BW) of pups born to ΔGRA17-immunized dams were not different compared to pups born to naïve control dams (P = 0.24). However, a marked reduction in the litter size (P < 0.001), survival rate, and BW (P < 0.01) of pups born to non-immunized and infected dams was detected. Also, immunized dams infected with type II Pru strain had significantly (P < 0.001) less cyst burden in the brain compared with non-immunized and infected dams. These findings show that immunization with ΔGRA17 strain evokes cell-mediated and neutralizing antibody responses and confers some degree of protection against challenge with homologous and heterologous virulent T. gondii strains.
Collapse
Affiliation(s)
- 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
| | - Hany M Elsheikha
- Faculty of Medicine and Health Sciences, School of Veterinary Medicine and Science, University of Nottingham, Loughborough, United Kingdom
| | - Wei-Ning 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 Animal Science and Veterinary Medicine, Shandong Agricultural University, Taian, China
| | - Kai Chen
- 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
| | - Dong-Mei Yue
- 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
| | - Xiao-Xuan 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
| | - Si-Yang Huang
- 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
| |
Collapse
|
13
|
Ferreira MN, Bonini-Domingos CR, Fonseca Estevão I, de Castro Lobo CL, Souza Carrocini GC, Silveira-Carvalho AP, Ricci O, de Mattos LC, Brandão de Mattos CC. Anti-Toxoplasma gondii antibodies in patients with beta-hemoglobinopathies: the first report in the Americas. BMC Res Notes 2017; 10:211. [PMID: 28615064 PMCID: PMC5471967 DOI: 10.1186/s13104-017-2535-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2016] [Accepted: 06/05/2017] [Indexed: 02/06/2023] Open
Abstract
Background In Brazil, there have been no previous studies of Toxoplasma gondii infection in sickle cell anemia patients and carriers of severe forms of beta-thalassemia. This study evaluated T. gondii infection in patients with beta-hemoglobinopathies. Methods A total of 158 samples, 77 (48.7%) men and 81 (51.3%) women, were evaluated. Three groups were formed: G1 (85 patients with sickle cell disease); G2 (11 patients with homozygous beta-thalassemia; G3 (62 patients with heterozygous beta-thalassemia). ELISA was employed to identify anti-T. gondii IgM and IgG antibodies, and molecular analysis was performed to determine beta-hemoglobin mutations. Fisher’s exact test was used to compare frequencies of anti-T. gondii IgM and IgG antibodies in respect to gender and age. Results Anti-T. gondii IgG antibodies were found in 43.5% of individuals in G1, 18.1% in G2 and 50% in G3. All samples from G1 and G2 were seronegative for anti-T. gondii IgM antibodies, but 3.2% from G3 were seropositive. Considering anti-T. gondii IgG antibodies, no statistical significant differences were found between these groups nor in seroprevalence between genders within each group. Despite this, comparisons of the mean ages between G1, G2 and G3 were statistically significant (G2 vs. G1: p value = 0.0001; G3 vs. G1: p-value <0.0001; G3 vs. G2: p-value = 0.0001). Conclusion A comparison by age of patients with sickle cell anemia showed a trend of lower risk of infection among younger individuals. Therefore, this study demonstrates that T. gondii infection occurs in patients with beta-thalassemia and sickle cell anemia in Brazil as seen by the presence of anti-T. gondii IgM and IgG antibodies.
Collapse
Affiliation(s)
- Marina Neves Ferreira
- Department of Biology, Universidade Estadual Paulista "Júlio de Mesquita Filho", Instituto de Biociências, Letras e Ciências Exatas-IBILCE-UNESP, São José do Rio Preto, SP, Brazil.,Immunogenetics Laboratory, Department of Molecular Biology, Faculdade de Medicina de São José do Rio Preto-FAMERP, Avenida Brigadeiro Faria Lima, 5416, São José do Rio Preto, SP, 15090-000, Brazil.,FAMERP Toxoplasma Research Group, Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, SP, Brazil.,Faculdade de Medicina Veterinária e Zootecnia, Universidade de São Paulo, São Paulo, Brazil
| | - Claudia Regina Bonini-Domingos
- Department of Biology, Universidade Estadual Paulista "Júlio de Mesquita Filho", Instituto de Biociências, Letras e Ciências Exatas-IBILCE-UNESP, São José do Rio Preto, SP, Brazil
| | - Isabeth Fonseca Estevão
- Department of Biology, Universidade Estadual Paulista "Júlio de Mesquita Filho", Instituto de Biociências, Letras e Ciências Exatas-IBILCE-UNESP, São José do Rio Preto, SP, Brazil
| | - Clarice Lopes de Castro Lobo
- Clinical Hematology Division, Instituto de Hematologia Arthur de Siqueira Cavalcanti-HEMORIO, Rio de Janeiro, RJ, Brazil
| | - Gisele Cristina Souza Carrocini
- Department of Biology, Universidade Estadual Paulista "Júlio de Mesquita Filho", Instituto de Biociências, Letras e Ciências Exatas-IBILCE-UNESP, São José do Rio Preto, SP, Brazil
| | - Aparecida Perpétuo Silveira-Carvalho
- Immunogenetics Laboratory, Department of Molecular Biology, Faculdade de Medicina de São José do Rio Preto-FAMERP, Avenida Brigadeiro Faria Lima, 5416, São José do Rio Preto, SP, 15090-000, Brazil.,FAMERP Toxoplasma Research Group, Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, SP, Brazil
| | - Octávio Ricci
- Department of Medicine, Faculdade de Medicina de São José do Rio Preto-FAMERP, São José do Rio Preto, SP, Brazil.,Regional Blood Center-Hemocentro de São José do Rio Preto-Fundação Faculdade Regional de Medicina-FUNFARME, São José do Rio Preto, SP, Brazil
| | - Luiz Carlos de Mattos
- Immunogenetics Laboratory, Department of Molecular Biology, Faculdade de Medicina de São José do Rio Preto-FAMERP, Avenida Brigadeiro Faria Lima, 5416, São José do Rio Preto, SP, 15090-000, Brazil.,FAMERP Toxoplasma Research Group, Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, SP, Brazil
| | - Cinara Cássia Brandão de Mattos
- Immunogenetics Laboratory, Department of Molecular Biology, Faculdade de Medicina de São José do Rio Preto-FAMERP, Avenida Brigadeiro Faria Lima, 5416, São José do Rio Preto, SP, 15090-000, Brazil. .,FAMERP Toxoplasma Research Group, Faculdade de Medicina de São José do Rio Preto, São José do Rio Preto, SP, Brazil.
| |
Collapse
|
14
|
Identification and co-localization of perforin-like (TgPLP1) protein in Toxoplasma gondii bradyzoites. Exp Parasitol 2015; 153:39-44. [DOI: 10.1016/j.exppara.2015.02.005] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2014] [Revised: 02/10/2015] [Accepted: 02/12/2015] [Indexed: 01/20/2023]
|
15
|
Chen JL, Ge YY, Zhang J, Qiu XY, Qiu JF, Wu JP, Wang Y. The dysfunction of CD4(+)CD25(+) regulatory T cells contributes to the abortion of mice caused by Toxoplasma gondii excreted-secreted antigens in early pregnancy. PLoS One 2013; 8:e69012. [PMID: 23874852 PMCID: PMC3714236 DOI: 10.1371/journal.pone.0069012] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2013] [Accepted: 06/11/2013] [Indexed: 11/19/2022] Open
Abstract
Toxoplasma gondii is an opportunistic intracellular parasite that is highly prevalent in human and warm-blooded animals throughout the world, leading to potentially severe congenital infections. Although the abortion caused by T. gondii is believed to be dependent on the timing of maternal infection during pregnancy, the mechanism remains unclear. This study was focused on the effects of T. gondii excreted-secreted antigens on pregnant outcomes and CD4(+)CD25(+) Foxp3(+) regulatory T cells at different stages of pregnancy. The results showed that in mice the frequency and suppressive function of CD4(+)CD25(+) regulatory cells were diminished after injection of T. gondii excreted-secreted antigens at early and intermediate stages of pregnancy. The abortion caused by T. gondii excreted-secreted antigens at early pregnancy could be partly prevented by adoptively transferring of CD4(+)CD25(+) cells from the mice injected with T. gondii excreted-secreted antigens at late pregnancy, but not from the mice with the same treatment at early pregnancy. Furthermore, T. gondii excreted-secreted antigens induced apoptosis of CD4(+)CD25(+) regulatory cells of mice in early and intermediate stages of pregnancy by down-regulating their Bcl-2 expressions and Bcl-2/Bax ratio. This study provides new insights into the mechanism that T. gondii infection is the high risk factor for abortion in early pregnancy.
Collapse
Affiliation(s)
- Jin-ling Chen
- Department of Pathogen Biology, Key Laboratory of Pathogen Biology of Jiangsu Province, Nanjing Medical University, Nanjing, Jiangsu, China
- Department of Parasitology and Microbiology, School of Medicine, Nantong University, Nantong, Jiangsu, China
| | - Yi-yue Ge
- Department of Pathogen Biology, Key Laboratory of Pathogen Biology of Jiangsu Province, Nanjing Medical University, Nanjing, Jiangsu, China
- Institute of Pathogen Microbiology, Jiangsu Provincial Center for Disease Prevention and Control, Nanjing, Jiangsu, China
| | - Jie Zhang
- Department of Pathogen Biology, Key Laboratory of Pathogen Biology of Jiangsu Province, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Xiao-yan Qiu
- Department of Pathogen Biology, Key Laboratory of Pathogen Biology of Jiangsu Province, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jing-fan Qiu
- Department of Pathogen Biology, Key Laboratory of Pathogen Biology of Jiangsu Province, Nanjing Medical University, Nanjing, Jiangsu, China
| | - Jiang-ping Wu
- Nanjing Maternity and Child Health Care Hospital Affiliated to Nanjing Medical University, Nanjing, Jiangsu, China
| | - Yong Wang
- Department of Pathogen Biology, Key Laboratory of Pathogen Biology of Jiangsu Province, Nanjing Medical University, Nanjing, Jiangsu, China
- * E-mail:
| |
Collapse
|
16
|
Cui X, Lei T, Yang D, Hao P, Li B, Liu Q. Toxoplasma gondii immune mapped protein-1 (TgIMP1) is a novel vaccine candidate against toxoplasmosis. Vaccine 2012; 30:2282-7. [DOI: 10.1016/j.vaccine.2012.01.073] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2011] [Revised: 12/28/2011] [Accepted: 01/23/2012] [Indexed: 01/19/2023]
|
17
|
de Mattos CDCB, Spegiorin LCJF, Meira CDS, Silva TDC, Ferreira AIDC, Nakashima F, Pereira-Chioccola VL, de Mattos LC. Anti-Toxoplasma gondii antibodies in pregnant women and their newborn infants in the region of São José do Rio Preto, São Paulo, Brazil. SAO PAULO MED J 2011; 129:261-6. [PMID: 21971902 PMCID: PMC10896019 DOI: 10.1590/s1516-31802011000400010] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/19/2010] [Revised: 07/19/2010] [Accepted: 04/01/2011] [Indexed: 11/21/2022] Open
Abstract
CONTEXT AND OBJECTIVE Toxoplasmosis transmission during pregnancy can cause severe sequelae in fetuses and newborns. Maternal antibodies may be indicators of risk or immunity. The aim here was to evaluate seropositivity for anti-Toxoplasma gondii (anti-T. gondii) immunoglobulin M (IgM) and immunoglobulin G (IgG) antibodies and IgG avidity in pregnant women and their newborn infants. DESIGN AND SETTING Cross-sectional study in a high-risk pregnancy outpatient clinic. METHODS Serum samples from pregnant women (n = 87) and their respective newborns (n = 87) were evaluated for anti-T. gondii antibodies using indirect immunofluorescence (IIF) (IgM and IgG), enzyme-linked immunosorbent assay (ELISA) (IgG) and an avidity test. RESULTS Anti-T. gondii antibodies were identified in 64.4% of the serum samples from the mothers and their infants (56/87). Except for two maternal serum samples (2.3%), all others were negative for anti-T. gondii IgM antibodies, using IIF. The results showed that 92.9% of the pregnant women had high IgG avidity indexes (> 30%) and four samples had avidity indexes between 16 and 30%. Two women in the third trimester of pregnancy were positive for anti-T. gondii IgM antibodies; their babies had avidity indexes between 16 and 30%. The avidity indexes of serum from the other 83 newborns were similar to the results from their mothers. CONCLUSIONS The results showed that 2% of the pregnant women were at risk of T. gondii transmission during the gestational period. These data seem to reflect the real situation of gestational toxoplasmosis in the northwestern region of the state of São Paulo.
Collapse
Affiliation(s)
- Cinara de Cássia Brandão de Mattos
- MSc. Doctoral student in Health Sciences, Immunogenetics Laboratory, Department of Molecular Biology, Faculdade de Medicina de São José do Rio Preto (Famerp), São José do Rio Preto, São Paulo, Brazil.
| | - Lígia Cosentino Junqueira Franco Spegiorin
- MD, MSc. Doctoral student in Health Sciences, Department of Gynecology and Obstetrics, Faculdade de Medicina de São José do Rio Preto (Famerp), Hospital de Base, Fundação Faculdade Regional de Medicina (Funfarme), São José do Rio Preto, São Paulo, Brazil.
| | | | | | - Ana Iara da Costa Ferreira
- MSc. Immunogenetics Laboratory, Department of Molecular Biology, Faculdade de Medicina de São José do Rio Preto (Famerp), São José do Rio Preto, São Paulo, Brazil.
| | - Fabiana Nakashima
- MSc. Immunogenetics Laboratory, Department of Molecular Biology, Faculdade de Medicina de São José do Rio Preto (Famerp), São José do Rio Preto, São Paulo, Brazil.
| | - Vera Lúcia Pereira-Chioccola
- PhD. Scientific Researcher, Laboratory of Molecular Biology of Parasites, Instituto Adolfo Lutz, São Paulo, Brazil.
| | - Luiz Carlos de Mattos
- PhD. Full Professor, Immunogenetics Laboratory, Department of Molecular Biology, Faculdade de Medicina de São José do Rio Preto (Famerp), São José do Rio Preto, São Paulo, Brazil.
| |
Collapse
|
18
|
Abstract
Toxoplasma gondii is an important human pathogen with a worldwide distribution. It is primarily of medical importance for pregnant women and immunocompromised patients. Primary infection of the former is often associated with fetal infection, which can lead to abortion or severe neonatal malformation. Immunocompromised patients are at risk of contracting the severe form of the disease that may be fatal. Thus, detection of T. gondii infection with high sensitivity and specificity is crucial in the management of the disease. Toxoplasmosis is generally diagnosed by demonstrating specific immunoglobulin M (IgM) and IgG antibodies to toxoplasma antigens in the patient's serum sample. Most of the commercially available tests use T. gondii native antigens and display wide variations in test accuracy. Recombinant antigens have great potential as diagnostic reagents for use in assays to detect toxoplasmosis. Thus in this review, we address recent advances in the use of Toxoplasma recombinant proteins for serodiagnosis of toxoplasmosis.
Collapse
Affiliation(s)
- Dupadahalli Kotresha
- Institute for Research in Molecular Medicine (INFORMM), Universiti Sains Malaysia, Penang, Malaysia
| | | |
Collapse
|
19
|
Wang T, Liu M, Gao XJ, Zhao ZJ, Chen XG, Lun ZR. Toxoplasma gondii: the effects of infection at different stages of pregnancy on the offspring of mice. Exp Parasitol 2010; 127:107-12. [PMID: 20619261 DOI: 10.1016/j.exppara.2010.07.003] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2010] [Revised: 06/25/2010] [Accepted: 07/01/2010] [Indexed: 11/28/2022]
Abstract
Congenital toxoplasmosis can cause fetal damage in humans and domestic animals. This study was focused on the effects of Toxoplasma gondii (Prugniaud strain) infection at different stages of pregnancy on the offspring of mice. Results showed that newborn mice from all infected groups were significantly lower in weight than those from the control group but significant difference was not found among these groups at day 60 after birth. The survival rate of the offspring from the group of mice infected at the earlier stage of pregnancy was significantly lower than those of infected and control groups. The positive offspring (with cysts found in their brain tissues) born from the mice infected at the earlier and intermediate stages of pregnancy showed a shorter latency and greater number of errors in the step-through passive avoidance test than those born from the mice infected at the late stage of pregnancy, the control group and the negative offspring from the infected groups. The number of cysts in the brain tissue was significantly higher in the offspring born from the groups of mice infected at the earlier and intermediate stages of pregnancy than those from the group of mice infected at the late stage of pregnancy. In addition, our results indicated that a high congenital transmission rate (90%) occurred in this NIH mouse model. In conclusion, the earlier and intermediate maternal infection of T. gondii can result in severe congenital toxoplasmosis, exhibiting conditions such as stillbirth or non-viability, and learning or memory capability damage in this mouse model. These results not only provide useful data for better understanding the effects of T. gondii infection on the offspring of mice infected at different stages of pregnancy but also for better consideration of the effect of this infection on other mammalian hosts including humans.
Collapse
Affiliation(s)
- Tao Wang
- Center for Parasitic Organisms, State Key Laboratory of Biocontrol, School of Life Sciences, and Key Laboratory of Tropical Diseases Control, The Ministry of Education, Zhongshan Medical College, Sun Yat-Sen Zhongshan University, Guangzhou 510275, PR China
| | | | | | | | | | | |
Collapse
|
20
|
Serological prevalence of Toxoplasma gondii antibodies in pregnant women from Southern Brazil. Parasitol Res 2010; 106:661-5. [PMID: 20084396 DOI: 10.1007/s00436-009-1716-2] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/03/2009] [Accepted: 12/20/2009] [Indexed: 10/20/2022]
Abstract
During 15 months (01 April 2003-31 July 2004), 20,389 women showing positive pregnancy tests were included in a serological evaluation of toxoplasmosis prevalence using automated immunoenzymatic assays. The women's serum samples were tested for the presence of IgG and/or IgM antibodies. Overall, 53.03% of the women were positive for IgG and 3.26% were positive for IgM; the analysis used a chi-square adherence test and a significance level of 0.05 (chi(2)=14,720.35; p=0.00). To discriminate between recent and past infection, IgG avidity tests (n=166) were carried out, of which 28.3% (n=47) presented low avidity. The seroconversion index observed in this study was 0.44%. The seroprevalence results obtained were similar to other serology data found in other regions of Brazil. These data demonstrate the importance of continuous regional and national seroepidemiological inquiries to define public health strategies that can revert and reduce serological prevalence, as described in other countries where toxoplasmosis monitoring is mandatory.
Collapse
|
21
|
Liu MM, Yuan ZG, Peng GH, Zhou DH, He XH, Yan C, Yin CC, He Y, Lin RQ, Song HQ, Zhu XQ. Toxoplasma gondii microneme protein 8 (MIC8) is a potential vaccine candidate against toxoplasmosis. Parasitol Res 2010; 106:1079-84. [DOI: 10.1007/s00436-010-1742-0] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2009] [Accepted: 01/13/2010] [Indexed: 12/15/2022]
|
22
|
Strhársky J, Klement C, Hrubá F. Seroprevalence of Toxoplasma gondii antibodies in the Slovak Republic. Folia Microbiol (Praha) 2010; 54:553-8. [DOI: 10.1007/s12223-009-0081-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2008] [Revised: 07/03/2009] [Indexed: 11/28/2022]
|
23
|
Martínez-Gómez F, García-González LF, Mondragón-Flores R, Bautista-Garfias CR. Protection against Toxoplasma gondii brain cyst formation in mice immunized with Toxoplasma gondii cytoskeleton proteins and Lactobacillus casei as adjuvant. Vet Parasitol 2009; 160:311-5. [DOI: 10.1016/j.vetpar.2008.11.017] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2008] [Revised: 11/14/2008] [Accepted: 11/17/2008] [Indexed: 11/24/2022]
|
24
|
Xue M, He S, Cui Y, Yao Y, Wang H. Evaluation of the immune response elicited by multi-antigenic DNA vaccine expressing SAG1, ROP2 and GRA2 against Toxoplasma gondii. Parasitol Int 2008; 57:424-9. [DOI: 10.1016/j.parint.2008.05.001] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2008] [Revised: 04/29/2008] [Accepted: 05/02/2008] [Indexed: 10/22/2022]
|
25
|
Prieto M, Schilrreff P, Tesoriero MD, Morilla M, Romero E. Brain and muscle of Wistar rats are the main targets of intravenous dendrimeric sulfadiazine. Int J Pharm 2008; 360:204-12. [DOI: 10.1016/j.ijpharm.2008.04.045] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/09/2008] [Revised: 04/16/2008] [Accepted: 04/17/2008] [Indexed: 11/17/2022]
|
26
|
Brunet J, Pfaff AW, Abidi A, Unoki M, Nakamura Y, Guinard M, Klein JP, Candolfi E, Mousli M. Toxoplasma gondii exploits UHRF1 and induces host cell cycle arrest at G2 to enable its proliferation. Cell Microbiol 2007; 10:908-20. [PMID: 18005238 DOI: 10.1111/j.1462-5822.2007.01093.x] [Citation(s) in RCA: 67] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Toxoplasma gondii is an obligate intracellular parasite that causes severe disease in humans. It is able to infect all nucleated mammalian cells leading to lifelong persistence of the parasite in the host. Here, we studied the effect of T. gondii infection on host cell proliferation and explored the molecular mechanisms involved in host cell cycle progression. We found that T. gondii induced G1/S transition in host cells in the presence of UHRF1, followed by G2 arrest after cyclin B1 downregulation which is probably the major cause of the arrest. Other molecules at the G2/M checkpoint including p53, p21 and Cdk1 were normally regulated. Interestingly, while parasite proliferation was normal in cells that were in the G2 phase, it was suppressed in G1-arrested cells induced by UHRF1-siRNA, indicating the importance of the G2 phase via UHRF1-induced G1/S transition for T. gondii growth.
Collapse
Affiliation(s)
- Julie Brunet
- Institut de Parasitologie et de Pathologie Tropicale de Strasbourg, UPRES E.A. 3950 Interactions Cellulaires et Moléculaires Hôte-Parasite, Faculté de Médecine, Université Louis Pasteur, 67000 Strasbourg, France
| | | | | | | | | | | | | | | | | |
Collapse
|
27
|
Elsheikha HM. Congenital toxoplasmosis: priorities for further health promotion action. Public Health 2007; 122:335-53. [PMID: 17964621 DOI: 10.1016/j.puhe.2007.08.009] [Citation(s) in RCA: 127] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2007] [Revised: 06/09/2007] [Accepted: 08/10/2007] [Indexed: 10/22/2022]
Abstract
Toxoplasmosis is a disease of considerable public health impact. As the transmission, occurrence and phenotype of this disease are influenced in a complex way by host genetics, immunity, behaviour and by the agent characteristics, prevention will not be simple. This article aimed to review studies defining seroprevalence of and characteristic sociodemographic, biological and lifestyle risk factors for Toxoplasma gondii infection in pregnant women, to evaluate screening and educational programmes, and to assemble recommendations for combating toxoplasmosis in populations at risk. Electronic databases were searched, using a specific search strategy, from 1975 to 2007. There is a high prevalence of T. gondii antibodies in pregnant women worldwide, with some geographic discrepancies attributed to climatic conditions, local food customs, hygiene, lifestyle and cultural differences. The main risk factors for toxoplasmosis in pregnant women are unsanitary feeding habits, poor immune system, contact with cats, contact with soil, pregnancy, number of births, older age, race, travelling outside the country, drinking beverages prepared with unboiled water, consumption of municipal or uncontrolled (well/spring) water and T. gondii strain virulence. Knowledge of these risk factors helps to identify priorities for further epidemiological work and defines effective preventive measures along five main themes of action: information and health education; screening of pregnant women and infants; limiting harm from risk behaviour; treatment of cases found to be at risk; and vaccination.
Collapse
Affiliation(s)
- H M Elsheikha
- Division of Veterinary Medicine, The University of Nottingham, Leicestershire LE12 5RD, UK.
| |
Collapse
|
28
|
|
29
|
Kodym P, Hrdá S, Machala L, Rozsypal H, Stanková M, Malý M. Prevalence and Incidence of Toxoplasma Infection in HIV-Positive Patients in the Czech Republic. J Eukaryot Microbiol 2006; 53 Suppl 1:S160-1. [PMID: 17169044 DOI: 10.1111/j.1550-7408.2006.00215.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
- Petr Kodym
- National Institute of Public Health, National Reference Laboratory for Toxoplasmosis, Prague, Czech Republic.
| | | | | | | | | | | |
Collapse
|
30
|
Abstract
Perspective on the paper by Schmidt et al (see page 661)
Collapse
Affiliation(s)
- R Gilbert
- Centre for Epidemiology and Biostatistics, Institute of Child Health, 30 Guilford Street, London WC1N 1EH, UK.
| | | |
Collapse
|
31
|
Khan A, Jordan C, Muccioli C, Vallochi AL, Rizzo LV, Belfort R, Vitor RW, Silveira C, Sibley LD. Genetic divergence of Toxoplasma gondii strains associated with ocular toxoplasmosis, Brazil. Emerg Infect Dis 2006; 12:942-9. [PMID: 16707050 PMCID: PMC3373049 DOI: 10.3201/eid1206.060025] [Citation(s) in RCA: 199] [Impact Index Per Article: 11.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Brazilian strains of T. gondii differ from lineages in North America and Europe; these differences may underlie severe ocular disease. Previous studies have shown a high prevalence of toxoplasmosis and the frequent occurrence of ocular disease in Brazil. To identify the genotypes of parasite strains associated with ocular disease, we compared 25 clinical and animal isolates of Toxoplasma gondii from Brazil to previously characterized clonal lineages from North America and Europe. Multilocus nested polymerase chain reaction analysis was combined with direct sequencing of a polymorphic intron to classify strains by phylogenetic methods. The genotypes of T. gondii strains isolated from Brazil were highly divergent when compared to the previously described clonal lineages. Several new predominant genotypes were identified from different regions of Brazil, including 2 small outbreaks attributable to foodborne or waterborne infection. These findings show that the genetic makeup of T. gondii is more complex than previously recognized and suggest that unique or divergent genotypes may contribute to different clinical outcomes of toxoplasmosis in different localities.
Collapse
Affiliation(s)
- Asis Khan
- Washington University School of Medicine, St. Louis, Missouri, USA
| | - Catherine Jordan
- Washington University School of Medicine, St. Louis, Missouri, USA
| | | | | | | | | | | | | | - L. David Sibley
- Washington University School of Medicine, St. Louis, Missouri, USA
| |
Collapse
|
32
|
Prieto MJ, Bacigalupe D, Pardini O, Amalvy JI, Venturini C, Morilla MJ, Romero EL. Nanomolar cationic dendrimeric sulfadiazine as potential antitoxoplasmic agent. Int J Pharm 2006; 326:160-8. [PMID: 16920292 DOI: 10.1016/j.ijpharm.2006.05.068] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2006] [Revised: 04/25/2006] [Accepted: 05/28/2006] [Indexed: 11/22/2022]
Abstract
The high doses of sulfadiazine (SDZ), used in synergistic combination with pyrimethamine, are mainly responsible for severe side effects and discontinuation of toxoplasmosis treatments. In the search for new strategies that improve the efficacy of treatments with reduced doses of SDZ, we have determined the performance of cationic G4 (DG4) and anionic G4.5 (DG4.5) poly(amidoamine) (PAMAM) dendrimers to act as SDZ nanocarriers. Both dendrimers could efficiently load SDZ (SDZ-DG4 and SDZ-DG4.5) up to a ratio of 30 molecules SDZ per dendrimer molecule. The MTT assay on Vero and J774 cells showed no cytotoxicity for DG4.5 and its SDZ complex incubated between 0.03 and 33 microM of dendrimer concentration. On the other hand, DG4 and its SDZ complex resulted cytotoxic when incubated at dendrimer concentrations higher than 3.3 microM. Finally, complexes and empty dendrimers were in vitro tested against Vero cells infected with RH strain of Toxoplasma gondii along 4h of treatment. For SDZ-DG4.5 and DG4.5 to cause an infection decrease between 25 and 40%, respectively, a dendrimer concentration of 33 microM was required; however, SDZ-DG4 produced the highest infection decrease of 60% at 0.03 microM. These preliminary results, achieved with nanomolar doses of SDZ-DG4 as unique active principle, point to this complex as a suitable potential candidate for antitoxoplasmic therapy.
Collapse
Affiliation(s)
- M J Prieto
- Laboratorio de Diseño de Estrategias de Targeting de Drogas (LDTD), Departamento de Ciencia y Tecnología, Universidad Nacional de Quilmes, Roque Saenz Peña 180, Bernal B1876BXD, Buenos Aires, Argentina
| | | | | | | | | | | | | |
Collapse
|
33
|
Nielsen HV, Di Cristina M, Beghetto E, Spadoni A, Petersen E, Gargano N. Toxoplasma gondii: DNA vaccination with bradyzoite antigens induces protective immunity in mice against oral infection with parasite cysts. Exp Parasitol 2006; 112:274-9. [PMID: 16368092 DOI: 10.1016/j.exppara.2005.11.009] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2005] [Revised: 11/11/2005] [Accepted: 11/13/2005] [Indexed: 11/16/2022]
Abstract
Infection of the host by Toxoplasma gondii leads to an acute systemic dissemination of tachyzoites, followed by a chronic phase, in which bradyzoites, enclosed in cysts, persist in the brain, the heart, and other tissues. Among putative vaccine candidates, the bradyzoite antigens BAG1 and MAG1 look promising since they are preferentially expressed during the chronic stage of the parasite. This work focused on studying the immunogenicity of bradyzoite antigens in a mouse model of chronic toxoplasmosis. A mixture of plasmids directing the cytoplasmic expression of MAG1 and BAG1 in mammalian cells was used to immunize mice. We show here that immunized mice developed, preferentially, specific anti-MAG1 and anti-BAG1 IgG2a subclass antibodies, indicating a shift towards a Th1-like response after DNA immunization. We then demonstrated that DNA immunization followed by challenge infection elicited effective protection in mice, suggesting that bradyzoite antigens should be considered in the design of vaccines against toxoplasmosis.
Collapse
|
34
|
Buffolano W, Beghetto E, Del Pezzo M, Spadoni A, Di Cristina M, Petersen E, Gargano N. Use of recombinant antigens for early postnatal diagnosis of congenital toxoplasmosis. J Clin Microbiol 2005; 43:5916-24. [PMID: 16333076 PMCID: PMC1317184 DOI: 10.1128/jcm.43.12.5916-5924.2005] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2005] [Revised: 08/24/2005] [Accepted: 09/27/2005] [Indexed: 11/20/2022] Open
Abstract
The main objective of this work was to improve the early serologic diagnosis of toxoplasmosis in children at risk of congenital infection by using recombinant antigens. Serum samples from 104 infants born to mothers with primary Toxoplasma gondii infection acquired during pregnancy, of which 35 were congenitally infected and 22 had clinical silent toxoplasmosis at birth, were included. Immunoglobulin M (IgM), IgG, and IgG subtype antibodies against epitopes carried by fragments of T. gondii MIC2, MIC3, MIC4, M2AP, AMA1, and SAG1 gene products were measured by performing parallel enzyme immunoassays (Rec-ELISAs). Recombinant antigens preferentially reacted with IgG antibodies from infected infants compared to uninfected subjects (P < 0.0001), indicating that sera from infected children recognized a more diverse repertoire of antigens than sera transferred over the placenta from the mothers. Using two serial samples collected within 3 months of life, it was possible to demonstrate a neosynthesis of specific anti-MIC2 and anti-SAG1 immunoglobulin G, mainly of the IgG2 subtype, in 13 out of 20 infants with congenital toxoplasmosis. IgM antibodies in 97% of infected infants reacted with at least one of the recombinant antigens, confirming the diagnosis of congenital infection as soon as 2 months after birth (P < 0.0001). The use of recombinant antigens is effective in distinguishing T. gondii-infected from uninfected infants and shows that assays based on recombinant antigens improve the diagnosis of newborns with congenital toxoplasmosis.
Collapse
Affiliation(s)
- Wilma Buffolano
- Kenton Laboratories, Via Pontina km 30.400, 00040 Rome, Italy
| | | | | | | | | | | | | |
Collapse
|
35
|
Graille M, Stura EA, Bossus M, Muller BH, Letourneur O, Battail-Poirot N, Sibaï G, Gauthier M, Rolland D, Le Du MH, Ducancel F. Crystal Structure of the Complex between the Monomeric Form of Toxoplasma gondii Surface Antigen 1 (SAG1) and a Monoclonal Antibody that Mimics the Human Immune Response. J Mol Biol 2005; 354:447-58. [PMID: 16242717 DOI: 10.1016/j.jmb.2005.09.028] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2005] [Revised: 09/01/2005] [Accepted: 09/02/2005] [Indexed: 11/21/2022]
Abstract
Toxoplasma gondii, the intracellular parasite responsible for toxoplasmosis infects more than one-third of the world population and can be life-threatening for fetuses and immunocompromised patients. The surface protein SAG1 is an important immune target, which provides a strong immune response against the invasive tachyzoite while the other forms of the parasite, devoid of SAG1 at their surface, are multiplying. In addition to this role as a "hot spot" decoy, SAG1 is predicted to act as an adhesin during host-cell attachment through its binding to proteoglycans. To begin to understand the relationships between SAG1 epitopes and the ligand-binding site, we have solved the crystal structure of the monomeric form of T.gondii SAG1 complexed to a Fab derived from a monoclonal antibody raised against tachyzoite particles. This antibody competes strongly with human Toxoplasma-specific sera, suggesting that its epitope is part of an immunodominant region present on the surface of SAG1. The structure reveals that this conformational epitope, located within the SAG1 N-terminal domain, does not overlap with the proposed ligand-binding pocket. This study provides the first structural description of the monomeric form of SAG1, and significant insights into its dual role of adhesin and immune target during parasite infection.
Collapse
Affiliation(s)
- Marc Graille
- Département d'Ingénierie et d'Etudes des Protéines, Centre d'Etudes de Saclay, 91191 Gif-sur-Yvette, France
| | | | | | | | | | | | | | | | | | | | | |
Collapse
|
36
|
Lüder CGK, Gross U. Apoptosis and its modulation during infection with Toxoplasma gondii: molecular mechanisms and role in pathogenesis. Curr Top Microbiol Immunol 2005; 289:219-37. [PMID: 15791958 DOI: 10.1007/3-540-27320-4_10] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Infection with the obligate intracellular protozoan Toxoplasma gondii leads to lifelong persistence of the parasite in its mammalian hosts including humans. Apoptosis plays crucial roles in the interaction between the host and the parasite. This includes innate and adaptive defense mechanisms to restrict intracellular parasite replication as well as regulatory functions to modulate the host's immune response. Not surprisingly, however, T. gondii also extensively modifies apoptosis of its own host cell or of uninfected bystander cells. After infection, apoptosis is triggered in T lymphocytes and other leukocytes, thereby leading to suppressed immune responses to the parasite. T cell apoptosis may be largely mediated by Fas engagement but also occurs independently of Fas under certain conditions. Depending on the magnitude of T cell apoptosis, it is either associated with unrestricted parasite replication and severe pathology or facilitates a stable parasite-host-interaction. However, T. gondii has also evolved strategies to inhibit host cell apoptosis. Apoptosis is blocked by indirect mechanisms in uninfected bystander cells, thereby modulating the inflammatory response to the parasite. In contrast, inhibition of apoptosis in infected host cells by direct interference with apoptosis-signaling cascades is thought to facilitate the intracellular development of T. gondii. Blockade of apoptosis by intracellular parasites may be achieved by different means including interference with the caspase cascade, increased expression of antiapoptotic molecules by infected host cells, and a decreased activity of the poly(ADP-ribose) polymerase. The intriguing dual activity of T. gondii to both promote and inhibit apoptosis requires a tight regulation to promote a stable parasite host-interaction and establishment of persistent toxoplasmosis.
Collapse
Affiliation(s)
- C G K Lüder
- Institute of Medical Microbiology, Georg-August-University, Kreuzbergring 57, 37075 Göttingen, Germany.
| | | |
Collapse
|
37
|
Ertug S, Okyay P, Turkmen M, Yuksel H. Seroprevalence and risk factors for toxoplasma infection among pregnant women in Aydin province, Turkey. BMC Public Health 2005; 5:66. [PMID: 15958156 PMCID: PMC1177966 DOI: 10.1186/1471-2458-5-66] [Citation(s) in RCA: 84] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2005] [Accepted: 06/15/2005] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The aims of the present study were to determine the prevalence of toxoplasmosis in pregnant women at first trimester of their pregnancy and to follow up the seroconversion for next two trimesters, and to identify the risk factors and possible contamination routes in Aydin province, Turkey. METHOD The sample size was calculated as 423 on a prevalence of 50%, d=0.05 at a confidence level of 95% with 10% addition. It was a cross-sectional study with multistage sampling. After a questionnaire applied to the pregnant women, anti-Toxoplasma IgG antibodies were studied with ELISA and IFA, values in conflict with DA test, where IgM antibodies were studied with ELISA and for borderline or positive values of IgM avidity test was used. RESULTS The mean age of 389 (92.9%) of pregnant women in the study was 24.28+/-4.56 years, the seroprevalence of anti-Toxoplasma IgG antibodies for toxoplasmosis was 30.1%. Seroprevalence was increased with age (p=0.001) and with drinking water consumption other than bottled water (p=0.042). No significant relations were observed between anti-Toxoplasma IgG antibodies and education level, being native or migrant, abortion history, consumption of meat, vegetable and milk/milk products, personal or kitchen hygiene habits, cat owning at home of the pregnant women. No IgM antibody was detected. CONCLUSION One of every three pregnant women in Aydin was at risk of toxoplasmosis at the first trimester of their pregnancy. Increased seroprevalance with age was a predictable result because of increasing time of exposure. Increased seroprevalence with consumption of municipal and uncontrolled water (well/spring water) supplies was similar with latest epidemiological findings.
Collapse
Affiliation(s)
- Sema Ertug
- Department of Parasitology, Adnan Menderes University, School of Medicine, Aydin, Turkey
| | - Pinar Okyay
- Department of Public Health, Adnan Menderes University, School of Medicine, Aydin, Turkey
| | - Munevver Turkmen
- Department of Child Health, Adnan Menderes University, School of Medicine, Aydin, Turkey
| | - Hasan Yuksel
- Department of Gynecology, Adnan Menderes University, School of Medicine, Aydin, Turkey
| |
Collapse
|
38
|
Mofenson LM, Oleske J, Serchuck L, Van Dyke R, Wilfert C. Treating Opportunistic Infections among HIV-Exposed and Infected Children: Recommendations from CDC, the National Institutes of Health, and the Infectious Diseases Society of America. Clin Infect Dis 2005; 40 Suppl 1:S1-84. [DOI: 10.1086/427295] [Citation(s) in RCA: 48] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
|
39
|
Buffolano W, Lappalainen M, Hedman L, Ciccimarra F, Del Pezzo M, Rescaldani R, Gargano N, Hedman K. Delayed maturation of IgG avidity in congenital toxoplasmosis. Eur J Clin Microbiol Infect Dis 2004; 23:825-30. [PMID: 15558340 DOI: 10.1007/s10096-004-1226-1] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
Abstract
The aim of this comparative study was to investigate the clinical usefulness of the measurement of Toxoplasma gondii IgG avidity in the postnatal diagnosis of congenital toxoplasmosis. IgG avidity values in serum samples from infants with congenital infection were compared with those in samples from uninfected infants, all born to mothers with toxoplasmosis acquired during gestation. This analysis revealed that IgG avidity values soon after birth reflected maternal values in the large majority of the samples. Low or borderline IgG avidity values were systematically found in the cohort of congenitally infected subjects. After birth, IgG avidity values slowly increased over time for up to 2 years in congenitally infected subjects. On the contrary, IgG avidity values in the uninfected infants remained stable over time. The presence of low IgG avidity in a newborn can be considered a marker of maternal seroconversion in the second or third trimester of gestation and, as a consequence, an indicator of risk for congenital toxoplasmosis. An IgG avidity assay can be easily carried out with antibodies eluted from dried blood spots (Guthrie cards), providing an opportunity to retrospectively evaluate the risk of congenital infection in special clinical circumstances, for example when suspicion of congenital infection arises during late infancy.
Collapse
Affiliation(s)
- W Buffolano
- Pediatrics Department, Federico II Naples University, via Pansini 5, 80131 Naples, Italy.
| | | | | | | | | | | | | | | |
Collapse
|
40
|
Di Cristina M, Del Porto P, Buffolano W, Beghetto E, Spadoni A, Guglietta S, Piccolella E, Felici F, Gargano N. The Toxoplasma gondii bradyzoite antigens BAG1 and MAG1 induce early humoral and cell-mediated immune responses upon human infection. Microbes Infect 2004; 6:164-71. [PMID: 14998514 DOI: 10.1016/j.micinf.2003.11.009] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2003] [Accepted: 11/05/2003] [Indexed: 11/26/2022]
Abstract
Infection of humans by Toxoplasma gondii leads to an acute systemic phase, in which tachyzoites disseminate throughout the body, followed by a chronic phase characterized by the presence of tissue cysts, containing bradyzoites, in brain, heart and skeletal muscles. This work focused on studying the antigenic regions of bradyzoite-specific proteins involved in human B- and T-cell responses. To this aim, we constructed a phage-display library of DNA fragments derived from the bradyzoite-specific genes BAG1, MAG1, SAG2D, SAG4, BSR4, LDH2, ENO1 and p-ATPase. Challenge of the bradyzoite library with sera of infected individuals led to the identification of antigenic regions within BAG1 and MAG1 gene products. Analysis of the humoral and lymphoproliferative responses to recombinant antigens demonstrated that the BAG1 fragment induced T-cell proliferation in 34% of T. gondii-exposed individuals, while 50% of them had specific IgG. In the same subjects, the MAG1 fragment was recognized by T cells from 17% of the exposed donors and by antibodies from 73% of them. A detailed analysis of the antibody response against BAG1 and MAG1 antigen fragments demonstrated that the immune response against bradyzoites occurs early after infection in humans. Finally, we provide evidence that the T-cell response against BAG1 is associated with the production of interferon-gamma, suggesting that bradyzoite antigens should be considered in the design of potential vaccines in humans.
Collapse
|
41
|
Molestina RE, Payne TM, Coppens I, Sinai AP. Activation of NF-kappaB by Toxoplasma gondii correlates with increased expression of antiapoptotic genes and localization of phosphorylated IkappaB to the parasitophorous vacuole membrane. J Cell Sci 2003; 116:4359-71. [PMID: 12966164 DOI: 10.1242/jcs.00683] [Citation(s) in RCA: 133] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/17/2023] Open
Abstract
Mammalian cells infected with Toxoplasma gondii are resistant to apoptosis induced by a variety of stimuli. We have demonstrated that the host transcription factor NF-kappaB plays a pivotal role in the T.-gondii-mediated blockade of apoptosis because inhibition is lost in cells lacking the p65 (RelA) subunit of NF-kappaB (p65-/-). In the present study, we examined the effects of T. gondii infection on NF-kappaB activation and the expression of genes involved in the apoptotic cascade. Infection of wild-type mouse embryonic fibroblasts (MEFs) with T.-gondii-induced nuclear translocation of the p50 and p65 subunits of NF-kappaB as examined by immunoblotting of nuclear extracts, immunofluorescence and electrophoretic mobility shift assays. A comparison of apoptotic gene expression profiles from wild-type and p65-/- MEFs revealed distinct patterns of induction in response to T. gondii infection. In particular, the differences seen in the Bcl-2 and IAP families are consistent with the antiapoptotic responses observed in the resistant wild-type cells compared with the sensitive p65-/- fibroblasts. Consistent with NF-kappaB activation, T. gondii infection promoted phosphorylation of the inhibitor IkappaB. Interestingly, phosphorylated IkappaB was concentrated on the parasitophorous vacuole membrane (PVM), suggesting a parasite-directed event. Results from this study suggest that activation of NF-kappaB plays an important role in stimulation of antiapoptotic gene expression by T. gondii. Furthermore, recruitment of phosphorylated IkappaB to the PVM implies the presence of intrinsic factor(s) in T. gondii that might be used to manipulate the NF-kappaB signaling pathway in the host to elicit a survival response during infection.
Collapse
Affiliation(s)
- Robert E Molestina
- Department of Microbiology, Immunology, and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY 40536, USA
| | | | | | | |
Collapse
|
42
|
Payne TM, Molestina RE, Sinai AP. Inhibition of caspase activation and a requirement for NF-kappaB function in the Toxoplasma gondii-mediated blockade of host apoptosis. J Cell Sci 2003; 116:4345-58. [PMID: 12966169 DOI: 10.1242/jcs.00756] [Citation(s) in RCA: 99] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/21/2023] Open
Abstract
Mammalian cells infected with the protozoan parasite Toxoplasma gondii are resistant to many apoptotic stimuli transmitted along both the mitochondrial and death receptor pathways. Apoptosis, and its inhibition in infected cells, was examined using multiple morphological, molecular and biochemical approaches. The data strongly indicate manipulation of the host apoptotic machinery at multiple levels, focusing on the inhibition of host caspases. Activation of the pro-apoptotic caspase family of proteases is a biochemical hallmark of apoptosis. Caspase activation occurs in a highly ordered cascade triggered by the initiator caspases 8 and 9, which activate the executioner caspase, caspase 3. Our findings indicate a profound blockade of caspase activation and activity as the molecular basis for the inhibition of apoptosis in T.-gondii-infected cells. Caspase inhibition was demonstrated using multiple intrinsic and synthetic substrates. Although the specific inhibitory molecule remains to be identified, data indicate an absolute requirement for the host transcription factor NF-kappaB and, by extension, genes regulated by it. We propose that T. gondii activates the host survival response, thereby increasing the overall resistance of infected cells to apoptotic stimuli.
Collapse
Affiliation(s)
- T Matthew Payne
- Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, 800 Rose St, Lexington, KY 40536, USA
| | | | | |
Collapse
|
43
|
Beghetto E, Spadoni A, Buffolano W, Del Pezzo M, Minenkova O, Pavoni E, Pucci A, Cortese R, Felici F, Gargano N. Molecular dissection of the human B-cell response against Toxoplasma gondii infection by lambda display of cDNA libraries. Int J Parasitol 2003; 33:163-73. [PMID: 12633654 DOI: 10.1016/s0020-7519(02)00256-4] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The disorders generated by Toxoplasma gondii infection are closely associated with the competence of the host immune system and both humoral and cell mediated immunity are involved in response to parasite invasion. To identify antigens implicated in human B-cell responses, we screened a phage-display library of T. gondii cDNA fragments with sera of infected individuals. This approach identified a panel of recombinant phage clones carrying B-cell epitopes. All the peptide sequences selected by this procedure are regions of T. gondii gene products. These regions contain epitopes of the T. gondii antigens SAG1, GRA1, GRA7, GRA8 and MIC5, which are recognised by human immunoglobulins. Moreover, we report the isolation and characterisation of two additional immunodominant regions encoded by GRA3 and MIC3 genes, whose products have never been described as antigens of the human B-cell response against T. gondii infection. These results demonstrate potential of lambda-display technology for antigen discovery and for the study of the human antibody response against infectious agents.
Collapse
Affiliation(s)
- Elisa Beghetto
- Kenton Laboratories, Via Pontina km 30.400, 00040 Rome, Italy
| | | | | | | | | | | | | | | | | | | |
Collapse
|
44
|
Fabre E, Bartha J, de Miguel J, Rodríguez-Alarcón J, Dulín E, Farrán I, González A. Grupo de consenso sobre toxoplasmosis. ACTA ACUST UNITED AC 2003. [DOI: 10.1016/s0304-5013(03)75906-8] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
|
45
|
Bahia-Oliveira LMG, Jones JL, Azevedo-Silva J, Alves CC, Oréfice F, Addiss DG. Highly endemic, waterborne toxoplasmosis in north Rio de Janeiro state, Brazil. Emerg Infect Dis 2003; 9:55-62. [PMID: 12533282 PMCID: PMC2873742 DOI: 10.3201/eid0901.020160] [Citation(s) in RCA: 319] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
In Campos dos Goytacazes, northern Rio de Janeiro state, Brazil, reports of uveitis consistent with toxoplasmosis led to a survey of the prevalence and risk factors for Toxoplasma gondii infection in 1997-1999. The survey population was selected randomly from schools, randomly chosen communities, and an army battalion. Serum samples from 1,436 persons were tested. With results adjusted for age, 84% of the population in the lower socioeconomic group was seropositive, compared with 62% and 23% of the middle and upper socioeconomic groups, respectively (p<0.001). When multivariate analysis was performed, drinking unfiltered water was found to increase the risk of seropositivity for the lower socioeconomic (odds ratio [OR]: 3.0, 95% confidence interval [CI] 1.3 to 6.9) and middle socioeconomic (OR: 1.7, 95% CI 1.2 to 2.3) populations. We also found a high T. gondii seroprevalence in this Brazilian community. Drinking unfiltered water increased the risk of T. gondii seropositivity, indicating the potential importance of oocyst transmission in water in this region.
Collapse
Affiliation(s)
| | - Jeffrey L. Jones
- Centers for Disease Control and Prevention, Atlanta , Georgia, USA
| | - Juliana Azevedo-Silva
- Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Cristiane C.F. Alves
- Universidade Estadual do Norte Fluminense, Campos dos Goytacazes, Rio de Janeiro, Brazil
| | - Fernando Oréfice
- Escola de Medicina, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - David G. Addiss
- Centers for Disease Control and Prevention, Atlanta , Georgia, USA
| |
Collapse
|
46
|
Naoi K, Yano A. A theoretical analysis of the relations between the risk of congenital toxoplasmosis and the annual infection rates with a convincing argument for better public intervention. Parasitol Int 2002; 51:187-94. [PMID: 12113757 DOI: 10.1016/s1383-5769(02)00009-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
In a theoretical analysis of the present study, we quantitatively indicate a potential threat of congenital toxoplasmosis to Japanese young women by the use of a simple mathematical model or a special case of the well-known catalytic infection model. For introducing a risk function of congenital toxoplasmosis, an annual infection rate, r, was divided into r(1), the rate before age a(0 < a < 15), and r(2), the rate after age a. Presuming the values of r(1), r(2) and a on the basis of the current situation of Toxoplasma infection in Japan, simulation analyses were performed with the mathematical model. As the simulation clearly demonstrated, Japanese young women are potentially facing a threat of congenital toxoplasmosis, although the current risk of it is relatively lower. From the viewpoint of risk management, public intervention programs are required. Based on our analyses, public intervention programs can be classified into two groups: group 1 for women before age a and group 2 for those after age a, and each group is expected to give a different kind of effect to the risk of congenital toxoplasmosis. The present study implies that a certain public intervention program could augment the risk, inadvertently.
Collapse
Affiliation(s)
- Koji Naoi
- Department of Infection and Host Defense, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo-ku, Chiba 260-8670, Japan
| | | |
Collapse
|