9 research outputs found
Cytokine Profiles in Toxoplasmic and Viral Uveitis
BackgroundUveitis is a major cause of visual impairment throughout the world. Analysis of cytokine profiles in aqueous humor specimens may provide insight into the physiopathological processes that underly retinal damage in this context MethodsUsing a multiplex assay, we determined the concentrations of 17 cytokines and chemokines in aqueous humor specimens obtained from patients with ocular toxoplasmosis or viral uveitis and compared these concentrations with those in specimens obtained from patients with noninfectious intermediate uveitis or cataract ResultsFive mediators (interleukin [IL]-8, monocyte chemoattractant protein-1, tumor necrosis factor-α, IL-4, and IL-10) were detected in >50% of patients in all groups. In contrast, IL-5 and IL-12 were specific for ocular toxoplasmosis, and granulocyte monocyte colony-stimulating factor and IL-1 were specific for viral uveitis; these mediators could present specific markers for diagnostic purposes. Interferon-Îł, IL-6, and macrophage inflammatory protein-1ÎČ were common markers of ocular toxoplasmosis and viral uveitis. IL-17 was a common marker of ocular toxoplasmosis and intermediate uveitis ConclusionsWe found specific cytokine profiles for each type of uveitis, with large interindividual variations and no etiological or clinical correlations. Ocular cytokine mapping contributes to a better understanding of the physiopathology of specific forms of uveitis and provides guidance for new targeted treatmen
First isolation and molecular characterization of Toxoplasma gondii strains from human congenital toxoplasmosis cases in Monastir, tunisia
International audienceToxoplasma gondii is a protozoon parasite that can cause severe clinical problems such as congenital toxoplasmosis. The distribution of T. gondii genotypes varies from one geographic area to another. So far, little is known about the parasite genotypes in Tunisia, North Africa. The present study aimed isolating and genotyping T. gondii from the amniotic fluid (AF) and placenta of pregnant women in Monastir, Tunisia. Amniotic fluid and/or placenta from 80 women who acquired toxoplasma infection during pregnancy were tested by PCR and/or mouse bioassay. Genotyping of T. gondii isolates from these samples was performed with 15 microsatellite markers. Four viable T. gondii strains were isolated from either the AF or placenta of four women. Specifically, strains TUN001-MON1 and TUN002-MON2 were isolated from both the AF and placenta, TUN003-AHA from only the placenta, and TUN004-NEL from only the AF. The four viable strains were not virulent for mice. Genotyping revealed that the four strains were type II strains. This is the first report on isolation and genotyping of T. gondii from AF human samples in Tunisia. Further studies focused on T. gondii genotyping on a larger number of human cases and on animals in Tunisia are needed to improve the knowledge and epidemiology of toxoplasmosis
First isolation and genotyping of Toxoplasma gondii strains from domestic animals in Tunisia
International audienceAbstract The isolation and molecular typing of Toxoplasma gondii strains provide an essential basis for a better understanding of the parasiteâs genetic diversity, determinants of its geographical distribution and associated risks to human health. In this study, we isolated and genetically characterized T. gondii strains from domestic animals in Southern and coastal area of Tunisia. Blood, hearts and/or brains were collected from 766 domestic animals (630 sheep and 136 free-range chickens). Strain isolation from these samples was performed using mouse bioassay and genotyping was carried out with a multiplex PCR technique using 15 microsatellite markers. Thirty viable strains of T. gondii were successfully isolated from tissues of sheep (19/142) and chickens (11/33). In addition, 3 strains could be successfully genotyped from animal tissues for which mouse bioassay was unsuccessful. A large predominance of type II strains (nâ=â29) was found in the sampled regions, followed by type III (nâ=â3) and, for the first time in Tunisia, a single isolate of Africa 4 lineage from a sheep. Analyses of population genetics showed the presence of a divergent population of type II lineage in Tunisia, supporting limited recent migrations of strains between Tunisia and other countries of the world
Seroprevalence of Toxoplasma gondii among healthy blood donors in two locations in Tunisia and associated risk factors
International audienceToxoplasma gondii is a protozoan parasite that can be transmitted to humans through a variety of routes including blood transfusion. This study aimed to investigate the seroprevalence of T . gondii infection and associated risk factors in healthy blood donors in Tunisia. A total of 800 healthy blood donors from two blood centers in south and coastal Tunisia were analyzed for anti- T. gondii IgG and IgM antibodies by indirect immunofluorescence assay (IFA) and enzyme-linked immunoassays (ELISA), respectively. Structured questionnaires were used to gather information on risk factors for T . gondii infection during collection. The overall seroprevalence was 44.4% of which 352 (44%) and 3 (0.4%) were positive for IgG and both IgG and IgM anti- T. gondii antibodies, respectively. Multivariate analysis showed that T. gondii seropositivity was significantly associated with the birth place (adjusted odds ratio [OR] = 2.72; 95% confidence interval [CI]: 1.49â4.94) and the age of the donors (adjusted OR = 4.98; 95% CI: 1.50â16.58) which are independent risk factors. In addition, the variables of hand washing before eating (adjusted OR = 0.52; 95% CI: 0.37â0.74) and living in an urban environment (adjusted OR = 0.30; 95% CI: 0.13â0.71) are two protective factors. This study provided the first data on the seroprevalence and epidemiology of T. gondii infection in healthy blood donors in Tunisia.Toxoplasma gondii est un parasite protozoaire qui peut ĂȘtre transmis Ă lâhomme par diverses voies, dont la transfusion sanguine. Cette Ă©tude vise Ă Ă©tudier la sĂ©roprĂ©valence de lâinfection Ă T. gondii et les facteurs de risque associĂ©s chez les donneurs de sang sains en Tunisie. Au total, huit cents donneurs de sang sains de deux centres de transfusion sanguine du sud et de la cĂŽte tunisienne ont Ă©tĂ© analysĂ©s respectivement pour la recherche des anticorps IgG et IgM anti- T. gondii par immunofluorescence indirecte (IFA) et par dosage immuno-enzymatique (ELISA). Des questionnaires structurĂ©s ont Ă©tĂ© utilisĂ©s pour recueillir des informations sur les facteurs de risque dâinfection Ă T. gondii pendant la collecte. La sĂ©roprĂ©valence globale Ă©tait de 44,4 % dont 352 (44 %) et 3 (0,4 %) Ă©taient respectivement positifs pour les anticorps IgG et IgG/IgM anti- T. gondii . Une analyse multivariĂ©e a montrĂ© que la sĂ©ropositivitĂ© Ă T. gondii Ă©tait significativement associĂ©e au lieu de naissance (rapport de cĂŽtes ajustĂ© [OR] = 2,72 ; intervalle de confiance Ă 95 % [IC] : 1,49â4,94) et Ă lâĂąge des donneurs (OR ajustĂ© = 4,98 ; IC 95 % : 1,50â16,58) qui sont des facteurs de risque indĂ©pendants. De plus, le lavage des mains avant de manger (OR ajustĂ© = 0,52 ; IC 95 % : 0,37â0,74) et vivre dans un milieu urbain (OR ajustĂ© = 0,30 ; IC 95 % : 0,13â0,71) sont deux facteurs de protection. Cette Ă©tude a fourni les premiĂšres donnĂ©es sur la sĂ©roprĂ©valence et lâĂ©pidĂ©miologie de lâinfection Ă T. gondii chez les donneurs de sang sains en Tunisie
Seroprevalence of Toxoplasma gondii among healthy blood donors in two locations in Tunisia and associated risk factors
Toxoplasma gondii is a protozoan parasite that can be transmitted to humans through a variety of routes including blood transfusion. This study aimed to investigate the seroprevalence of T. gondii infection and associated risk factors in healthy blood donors in Tunisia. A total of 800 healthy blood donors from two blood centers in south and coastal Tunisia were analyzed for anti-T. gondii IgG and IgM antibodies by indirect immunofluorescence assay (IFA) and enzyme-linked immunoassays (ELISA), respectively. Structured questionnaires were used to gather information on risk factors for T. gondii infection during collection. The overall seroprevalence was 44.4% of which 352 (44%) and 3 (0.4%) were positive for IgG and both IgG and IgM anti-T. gondii antibodies, respectively. Multivariate analysis showed that T. gondii seropositivity was significantly associated with the birth place (adjusted odds ratio [OR] = 2.72; 95% confidence interval [CI]: 1.49â4.94) and the age of the donors (adjusted OR = 4.98; 95% CI: 1.50â16.58) which are independent risk factors. In addition, the variables of hand washing before eating (adjusted OR = 0.52; 95% CI: 0.37â0.74) and living in an urban environment (adjusted OR = 0.30; 95% CI: 0.13â0.71) are two protective factors. This study provided the first data on the seroprevalence and epidemiology of T. gondii infection in healthy blood donors in Tunisia
Murine neonatal infection provides an efficient model for congenital ocular toxoplasmosis
International audienceCongenital infection is one of the most serious settings of infection with the apicomplexan parasite Toxoplasma gondii. Ocular diseases, such as retinochoroiditis, are the most common sequels of such infection in utero. However, while numerous studies have investigated the physiopathology of acquired toxoplasmosis, congenital infection has been largely neglected so far. Here, we establish a mouse model of congenital ocular toxoplasmosis. Parasite load and ocular pathology have been followed for the first 4 weeks of life. Ocular infection developed slowly compared to cerebral infection. Even after 4 weeks, not all eyes were infected and ocular parasite load was low. Therefore, we evaluated a scheme of neonatal infection to overcome problems associated with congenital infection. Development of infection and physiopathology was similar, but at a higher, more reliable rate. In summary, we have established a valuable model of neonatal ocular toxoplasmosis, which facilitates the research of the underlying physiopathological mechanisms and new diagnostic approaches of this pathology
First report of Tunisian coastal water contamination by protozoan parasites using mollusk bivalves as biological indicators
In order to establish seawater contamination by emerging protozoan parasites, we used qPCR to molecularly characterize
and evaluate the parasitic burden of Giardia duodenalis, Cryptosporidium spp., Toxoplasma gondii, and Cyclospora
cayetanensis in 1255 wild bivalve mollusks collected along the Tunisian coasts. T. gondii, G. duodenalis and C. cayetanensis
were detected in 6.9% (99% CI = 1.6â12.2%) pools of Ruditapes decussatus. None of the samples were found
positive to Cryptosporidium spp.; 6.6% pools of R. decussatus were positive for T. gondii Type I, 1.6% for G. duodenalis
assemblage A, and 1.6% for the association T. gondii Type I/C. cayetanensis/G. duodenalis assemblage A. R. decussatus
harbored up to 77500 oocysts/sample of T. gondii, up to 395 cysts/sample of G. duodenalis, and 526 oocysts/sample of
C. cayetanensis. These results provide the first evidence that the Tunisian coasts are contaminated by zoonotic protozoan
parasites that can constitute a direct or indirect risk for human health
Cytokine Profiles in Toxoplasmic and Viral Uveitis
Background: Uveitis is a major cause of visual impairment throughout the world. Analysis of cytokine profiles in aqueous humor specimens may provide insight into the physiopathological processes that underly retinal damage in this context
Methods: Using a multiplex assay, we determined the concentrations of 17 cytokines and chemokines in aqueous humor specimens obtained from patients with ocular toxoplasmosis or viral uveitis and compared these concentrations with those in specimens obtained from patients with noninfectious intermediate uveitis or cataract
Results: Five mediators (interleukin [IL]â8, monocyte chemoattractant proteinâ1, tumor necrosis factorâα, IL-4, and IL-10) were detected in >50% of patients in all groups. In contrast, IL-5 and IL-12 were specific for ocular toxoplasmosis, and granulocyte monocyte colony-stimulating factor and IL-1 were specific for viral uveitis; these mediators could present specific markers for diagnostic purposes. Interferon-Îł, IL-6, and macrophage inflammatory protein-1ÎČ were common markers of ocular toxoplasmosis and viral uveitis. IL-17 was a common marker of ocular toxoplasmosis and intermediate uveitis
Conclusions: We found specific cytokine profiles for each type of uveitis, with large interindividual variations and no etiological or clinical correlations. Ocular cytokine mapping contributes to a better understanding of the physiopathology of specific forms of uveitis and provides guidance for new targeted treatmen