Discrimination between patients with acquired toxoplasmosis and congenital toxoplasmosis on the basis of the immune response to parasite antigens

Many persons infected with Toxoplasma gondii develop ocular lesions, Immunologic parameters in the response to I gondii were evaluated in infected persons with and without ocular lesions and in noninfected controls. Subjects were divided into groups on the basis of presence of serum antibodies to I: gondii, presence of ocular lesions, and clinical history. Production of interleukin-2 and interferon-gamma by peripheral blood mononuclear cells from patients with probable congenital toxoplasmosis was decreased, compared with that in persons with presumed acquired infection. Cell proliferation and delayed-type skin reaction induced by soluble toxoplasma tachyzoite antigen followed the same pattern. Asymptomatic persons showed high levels of interleukin-12 and interferon-gamma, whereas persons with ocular lesions had high interleukin-1 and tumor necrosis factor-alpha responses toward soluble toxoplasma tachyzoite antigen. These data suggest that patients with ocular disease due to congenital infection show tolerance toward the parasite. Furthermore, susceptibility to ocular lesions after acquired toxoplasmosis is associated with high levels of interleukin-1 and tumor necrosis factor-alpha, whereas resistance is associated with high levels of interleukin-12 and interferon-gamma.Univ São Paulo, ICB, Dept Immunol, BR-05509890 São Paulo, BrazilUniv São Paulo, Inst Heart, Lab Transplant Immunol, São Paulo, BrazilUniv São Paulo, Fac Med, Dept Ophthalmol, São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, São Paulo, BrazilUniv São Paulo, Sch Med, Div Clin Immunol & Allergy, Lab Med Invest, São Paulo, BrazilFundacao EJ Zerbini, São Paulo, BrazilUniv Fed Minas Gerais, Dept Biochem & Immunol, Belo Horizonte, MG, BrazilFundacao Osvaldo Cruz, Ctr Pesquisas Rene Rachou, Belo Horizonte, MG, BrazilNEI, Immunol Lab, NIH, Bethesda, MD 20892 USAUniversidade Federal de São Paulo, Dept Ophthalmol, São Paulo, BrazilWeb of Scienc

Recently Acquired Toxoplasma gondii Infection, Brazil

Soil exposure, eating undercooked meat, and having children are risk factors for acute infection and high rate of eye disease

Clinical pattern of ocular toxoplasmosis treated in a referral centre in Serbia

Purpose To analyze the clinical pattern of ocular toxoplasmosis (OT) in a referral centre in Serbia. Patients and methods The medical records of consecutive patients admitted for OT to the single referral centre for uveitis in Serbia between 2006 and 2010 were retrospectively analyzed. OT was diagnosed on the basis of typical fundus lesions and positive serology for Toxoplasma. Results In a total of 457 uveitis patients, OT was the third leading cause, with 59 patients (12.9%). Most OT cases (73%) were monocular. An active primary retinal lesion was observed in 36% and recurrent OT in 64% patients. Localization of lesions was central/paracentral (44%), juxtapapillar (27%), peripheral (19%), and multifocal (10%). Other ocular manifestations of inflammation included vitritis (44%), anterior uveitis (19%), and retinal vasculitis (10%). Complications included choroidal neovascularization in two and exudative retinal detachment with cataract, glaucoma, and cystoid macular oedema in one patient each. The detection of Toxoplasma-specific IgM antibodies in a single patient indicates a low rate of OT concomitant with acute infection. After treatment, the mean best-corrected visual acuity (BCVA) increased significantly. However, 14 (24%) patients ended up legally blind in the affected eye, of which 2 (3%) with bilateral blindness, all with a very poor BCVA (0.047 +/- 0.055) at presentation. Visual impairment and treatment outcome were both associated with central localization of lesions (P lt 0.0001 and P = 0.006, respectively). Conclusion OT is a significant cause of posterior uveitis in Serbia. Patients should be aware of the recurring nature of OT and react immediately if symptoms occur. Eye (2012) 26, 723-728; doi: 10.1038/eye.2012.20; published online 24 February 201

Cytokine profile in response to Cytomegalovirus associated with immune recovery syndrome after highly active antiretroviral therapy

Background: Several changes have occurred in the presentation and course of cytomegalovirus (CMV) retinitis in patients with AIDS since the introduction of HAART (highly active antiretroviral therapy). In some individuals who take HAART retinitis is kept under control even after the discontinuation of anti-CMV therapy. However, many of these patients develop intraocular inflammation. Uveitis, cataract, vitreitis, cystoid macular edema, epiretinal membrane, and disc edema may occur in patients with immune recovery syndrome (IRS).Methods: We evaluated the CMV-specific immune response in 55 patients by assessing CMV-specific lymphocyte proliferation, cytotoxicity, and cytokine production and correlated it with the clinical outcome.Results: Our data suggest that control of CMV retinitis is associated with acquisition of cytotoxic and lymphoproliferative responses to CMV. In addition, the upsurge of macular and disc edema seems associated with the production of interleukin-4 and tumor necrosis factor-cc, whereas vitreitis is associated with the production of interleukin-2 and interferon-gamma.Interpretation: The type of T-cell response that develops after HAART may determine the side effects of immune recovery and these effects are predictable based on the lymphokine profile produced by CMV-specific cells.Univ Sao Paulo, Dept Immunol, ICB, BR-05508900 Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Ophthalmol, Escola Paulista Med, Sao Paulo, BrazilUniv Sao Paulo, Sch Med, Dept Ophthalmol, BR-05508900 Sao Paulo, BrazilUniv Sao Paulo, Sch Med, Div Clin Immunol & Allergy, Fundacao Zerbini, BR-05508900 Sao Paulo, BrazilUniv Fed Sao Paulo, Dept Ophthalmol, Escola Paulista Med, Sao Paulo, BrazilWeb of Scienc

The role of inflammatory and anti-inflammatory cytokines in the progression of experimental autoimune uveitis (EAU).

Univ Sao Paulo, Div Clin Immunol & Allergy, BR-05508 Sao Paulo, BrazilUNIFESP, Dept Ophthalmol, Sao Paulo, BrazilUNIFESP, Dept Ophthalmol, Sao Paulo, BrazilWeb of Scienc

Ocular toxoplasmosis: More than just what meets the eye

Toxoplasma gondii is an intracellular parasite whose life cycle may include the man as an intermediate host. Close to a billion people are infected with this parasite worldwide. Ocular lesions may occur in up to 25% of those individuals infected. the infection may occur intra-uterus, through the placenta when the mother is infected during pregnancy. the parasite may also infect adults after the ingestion of contaminated food products. most notably meats or water. We have shown that although congenital and post-natal (acquired) infection results in similar ocular lesions, the immunological mechanisms behind the development of disease are different. On the other hand, contrary to published data obtained in mice, we were unable to find evidence that the T. gondii express superantigen activity for human lymphocytes. Our findings are important because they suggest that superantigen activity is not important as a pathological mechanism in human disease. Our data also suggest that, whereas the ocular lesion caused by infection after birth is the result of an excessive or dysfunctional immune response, the lesions caused by congenital infection may be due to a lack of an appropriate response to the parasite.Univ São Paulo, Inst Ciencias Biomed, Dept Immunol, BR-05508000 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, São Paulo, BrazilUniv São Paulo, Sch Med, Div Clin Immunol & Allergy, BR-05508000 São Paulo, BrazilUniversidade Federal de São Paulo, Dept Ophthalmol, São Paulo, BrazilWeb of Scienc