Pathogenesis of ocular toxoplasmosis

Smith, Justine R.; Ashander, Liam M.; Arruda, Sigrid; Cordeiro, Cynthia Azeredo; Lie, Shervi; Rochet, E; Belfort, Rubens; Furtado, João M.

doi:10.1016/j.preteyeres.2020.100882

Cited by 56 publications

(48 citation statements)

References 261 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In particular, the results showed a preference for Müller glial cells, which harboured a bulk of parasitophorous vacuoles and the highest parasite load. Moreover, parasite growth in these cells exceeded that in human dermal fibroblasts by over 50% [4,34]. Other studies conducted in the brain showed a preference of T. gondii for astrocytes, but it is important to notice that, although Müller cells are specialized macroglial cells, they are phenotypically different from astrocytes and are absent in the brain [37].…”

Section: Movement Of T Gondii Within the Human Retinamentioning

confidence: 87%

“…However, this is a rare situation during OT. Indeed, a recent study showed that the RPE produces Pigment Epithelial Derived Factor (PEDF) within hours of infection [4]. PEDF is an antiangiogenic factor, and its release at an early stage in the infection may prevent choroidal neovascularization [45].…”

Section: Infection Of the Rpe By T Gondiimentioning

confidence: 99%

“…Other haplogroups with atypical or recombinant genetics are less well known, with little information in the literature [54]. Recent results from PCRbased studies on patients with toxoplasmosis show differences in genotype distribution among different countries (Table 1) [4]. In many cases there is a similar distribution of OT across countries, but there is only little information on African regions.…”

Section: Toxoplasma Genotype Influences the Course Of Ocular Infectionmentioning

confidence: 99%

“…In the second, toxoplasmosis is acquired by eating raw or undercooked meat, vegetables or milk products, or by coming into contact with infected cat litter [3]. OT has been the subject of a considerable number of studies, and recent review papers have focused on specific aspects of the disease (see, for instance, [4]). However, deeper knowledge of the mechanisms of this pathology is necessary to provide new, more targeted treatment strategies.…”

Section: Introductionmentioning

confidence: 99%

See 3 more Smart Citations

Ocular Toxoplasmosis: Mechanisms of Retinal Infection and Experimental Models

2021

View full text Add to dashboard Cite

Ocular toxoplasmosis (OT) is caused by the parasite Toxoplasma gondii and affects many individuals throughout the world. Infection may occur through congenital or acquired routes. The parasites enter the blood circulation and reach both the retina and the retinal pigment epithelium, where they may cause cell damage and cell death. Different routes of access are used by T. gondii to reach the retina through the retinal endothelium: by transmission inside leukocytes, as free parasites through a paracellular route, or after endothelial cell infection. A main feature of OT is the induction of an important inflammatory state, and the course of infection has been shown to be influenced by the host immunogenetics. On the other hand, there is evidence that the T. gondii phenotype also has an impact on the distribution of the pathology in different areas. Although considerable knowledge has been acquired on OT, a deeper knowledge of its mechanisms is necessary to provide new, more targeted treatment strategies. In particular, in addition to in vitro and in vivo experimental models, organotypic, ex vivo retinal explants may be useful in this direction.

show abstract

Section: Movement Of T Gondii Within the Human Retinamentioning

confidence: 87%

Section: Infection Of the Rpe By T Gondiimentioning

confidence: 99%

Section: Toxoplasma Genotype Influences the Course Of Ocular Infectionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Ocular Toxoplasmosis: Mechanisms of Retinal Infection and Experimental Models

2021

View full text Add to dashboard Cite

show abstract

“…A primary infection during pregnancy may result in congenital infection causing abortion or fetal abnormalities, including hydrocephalus, intracranial calcifications and retinochoroiditis (Montoya and Liesenfeld, 2004). In the last years, ocular toxoplasmosis was identified not only following congenital infection but also in cases of postnatally acquired infections (Smith et al, 2020;Zhao and Ewald, 2020).…”

Section: Introductionmentioning

confidence: 99%

Key Limitations and New Insights Into the Toxoplasma gondii Parasite Stage Switching for Future Vaccine Development in Human, Livestock, and Cats

Mévélec

Lakhrif

Dimier‐Poisson

2020

Front. Cell. Infect. Microbiol.

View full text Add to dashboard Cite

Toxoplasmosis is a parasitic disease affecting human, livestock and cat. Prophylactic strategies would be ideal to prevent infection. In a One Health vaccination approach, the objectives would be the prevention of congenital disease in both women and livestock, prevention/reduction of T. gondii tissue cysts in food-producing animals; and oocyst shedding in cats. Over the last few years, an explosion of strategies for vaccine development, especially due to the development of genetic-engineering technologies has emerged. The field of vaccinology has been exploring safer vaccines by the generation of recombinant immunogenic proteins, naked DNA vaccines, and viral/bacterial recombinants vectors. These strategies based on single- or few antigens, are less efficacious than recombinant live-attenuated, mostly tachyzoite T. gondii vaccine candidates. Reflections on the development of an anti-Toxoplasma vaccine must focus not only on the appropriate route of administration, capable of inducing efficient immune response, but also on the choice of the antigen (s) of interest and the associated delivery systems. To answer these questions, the choice of the animal model is essential. If mice helped in understanding the protection mechanisms, the data obtained cannot be directly transposed to humans, livestock and cats. Moreover, effectiveness vaccines should elicit strong and protective humoral and cellular immune responses at both local and systemic levels against the different stages of the parasite. Finally, challenge protocols should use the oral route, major natural route of infection, either by feeding tissue cysts or oocysts from different T. gondii strains. Effective Toxoplasma vaccines depend on our understanding of the (1) protective host immune response during T. gondii invasion and infection in the different hosts, (2) manipulation and modulation of host immune response to ensure survival of the parasites able to evade and subvert host immunity, (3) molecular mechanisms that define specific stage development. This review presents an overview of the key limitations for the development of an effective vaccine and highlights the contributions made by recent studies on the mechanisms behind stage switching to offer interesting perspectives for vaccine development.

show abstract