Toxoplasma gondii is an opportunistic intracellular parasite which induces a highly strong type 1 cytokine response. The present study focuses on defining the factors influencing the outcome of infection with tachyzoites of the type I, highly lethal RH strain, relative to the type II, low virulence strain ME49. Infection with the RH strain led to widespread parasite dissemination and rapid deat...

Infection of mouse macrophages with Toxoplasma gondii elicits MAPK activation and IL-12 production, but host cell signaling pathways have not been clearly delineated. Here, we compared macrophage signaling in response to high virulence type I (RH) vs low virulence type II (ME49) strain infection. Tachyzoites of both strains induced p38 MAPK-dependent macrophage IL-12 release, although ME49 elic...

UNLABELLED Toxoplasma gondii ME49 is an obligatory intracellular apicomplexa parasite that causes toxoplasmosis in humans, domesticated and wild animals. Waterborne outbreaks of acute toxoplasmosis worldwide reinforce the transmission of Toxoplasma gondii ME49 to humans through contaminated water and may have a greater epidemiological impact than previously believed. In the quest for drug and v...

Toxoplasma gondii reportedly manipulates rodent behaviour to increase transmission to its definitive feline host. We compared the effects of mouse infection by two Type II strains of T. gondii, Prugniaud (PRU) and ME49, on attraction to cat odour, locomotor activity, anxiety, sensorimotor gating, and spatial working and recognition memory 2 months post-infection (mpi). Attraction to cat odour w...

Toxoplasma gondii is one of the most prevalent parasitic infections in world. Rh, NED and Me49 are of the most prevalent clonal types of the parasite isolated till now. Differences in pathogenicity and virulence of different types have been investigated in different studies. No controlled study was performed to compare the ability of different types to initiate humoral immune response. We inves...

C57BL/6 (B6) mice are genetically highly susceptible to chronic type II Toxoplasma gondii infections that invariably cause lethal toxoplasmic encephalitis. We examined the ability of an attenuated type I vaccine strain to elicit long-term immunity to lethal acute or chronic type II infections in susceptible B6 mice. Mice immunized with the type I cps1-1 vaccine strain were not susceptible to a ...

toxoplasma gondii is one of the most prevalent parasitic infections in world. rh, ned and me49 are of the most prevalent clonal types of the parasite isolated till now. differences in pathogenicity and virulence of different types have been investigated in different studies. no controlled study was performed to compare the ability of different types to initiate humoral immune response. we inves...

Conventional natural killer (cNK) cells, members of group 1 innate lymphoid cells, are a diverse cell subpopulation based on surface receptor expression, maturation, and functional potential. cNK cells are critical for early immunity to Toxoplasma gondii via IFNγ production. Acute cNK cell responses to infection with different strains of T. gondii have not yet been characterized in detail. Here...

To investigate the role that cytokines may have in the development of toxoplasmic encephalitis (TE), the levels of gamma interferon (IFN-gamma), tumor necrosis factor alpha (TNF-alpha), interleukin-12 (IL-12 ]p40[), IL-10, IL-6, IL-4, and IL-2 in serum were examined in CBA/Ca mice infected with a type II strain (ME49 or FORT) of Toxoplasma gondii. These strains caused severe (ME49) or mild (FOR...

To examine the immune environment of chronic Toxoplasma gondii infection in the brain, the characteristics of infection-immunity (premunition) in infection with T. gondii strain ME49 were investigated for 12 weeks postinfection (PI). The results showed that neuronal cell death, microglia infiltration and activation, inflammatory and anti-inflammatory cytokine expression, Stat1 phosphorylation, ...