Resistance to infection with Toxoplasma gondii was studied in mice lacking CD4 expression. Such mice developed more brain cysts and survived for a shorter time than did wild-type controls after peroral infection with ME49 cysts. After immunization with the ts-4 strain of T. gondii, CD4-deficient mice exhibited impaired resistance to a challenge infection with virulent RH tachyzoites. Thus, defi...

Drug treatment for toxoplasmosis is problematic, because current drugs cannot eradicate latent infection with Toxoplasma gondii and can cause bone marrow toxicity. Because latent infection remains after treatment, relapse of infection is a problem in both infections in immunocompromised patients and in congenitally infected patients. To identify lead compounds for novel drugs against Toxoplasma...

A longitudinal study of different parameters of the immune responses to Toxoplasma gondii was performed with sera of AIDS patients taken during and after clinically important Toxoplasma infections. Follow-up of patients lasted for 9 months on an average. The titres of the specific IgG and IgM antibodies were measured by an indirect fluorescent antibody test (IFAT), and the appearance of circula...

BACKGROUND Toxoplasmosis is a worldwide-distributed infection which is mostly asymptomatic but can cause serious health problems in congenitally-infected newborns and immunecompromised individuals. Research is undergoing both to improve Toxoplasma serological tests, which play the main role in laboratory diagnosis of the infection, and develop an effective vaccine to prevent the infection. Some...

Background: Toxoplasmosis is well known as an important infection in pregnant women. Although many serologic methods are available, diagnosis of early Toxoplasmosis may be extremely difficult. Objective: To detect the Toxoplasma IgG antibodies developed at the early stage of infection in pregnant women. Methods: 225 pregnant women, who were in the 2nd to 4th month of their pregnancy, enrolled i...

The behavioral manipulation hypothesis predicts that parasites can change host behavior in a way that benefits the parasites and not the host (extensively reviewed in [1–9]). In other words, the hypothesis predicts that genes of a parasite can produce an "extended" phenotype that manifests beyond a parasite's soma [10]. Protozoan parasite Toxoplasma gondii (henceforth toxoplasma) is an often-ci...

Objective: Sera from 186 sheep (93 rams and 93ewes) from Tabriz, North-West of Iran were evaluated for antibodies to Toxoplasma gondii using a commercial ELISA kit. Methods: The animals were divided into two age groups (< 2 years, and > 2 years). Results: Antibodies to T. gondii were found in 13 of 186 sheep (6.98%). Infection rate in ewes was higher than rams but this differe...

Introduction: Toxoplasma gondii is one of the most important foodborne pathogens. Toxoplasmosis causes abortion and neonatal loss in livestock and imposes significant losses to farming industry. Prevalence of T. gondii in sheep and goats was investigated in three adjacent geographical areas within Gilan province in north of Iran. Methods: Serum samples were collected from 247 sheep and 155 goat...

Serological screening and evaluation of exposure factors for Toxoplasma gondii transmission were conducted in 2126 pregnant women from southern Brazil. Specific antibodies against Toxoplasma gondii were presented by 74.5% (n=1583) of the pregnant women evaluated. Contact with soil was found to be the major factor for infection.

Toxoplasma gondii is a common protozoan parasite that infects warm-blooded animals throughout the world, including mice and humans. During infection, both, the parasite and the host, utilize various mechanisms to maximize their own reproductive success. Mice and humans are both the intermediate hosts for Toxoplasma gondii, which forms specialized vacuoles containing reproductive cysts in the fo...