Toxoplasmosis is a foodborne disease caused by Toxoplasma gondii, an obligate intracellular parasite. The parasite remains protected within a parasitophorous vacuole (PV), a specialized compartment formed within the infected host cell during and after invasion. Dense granules (GRA) are T. gondii specialized secretory organelles involved in PV development. GRA2 contributes to the formation of in...

Three families of chromosomally encoded beta-lactamases have been identified so far in Klebsiella pneumoniae clinical isolates: SHV (7), LEN (1), and very recently, OKP (5). These enzymes are closely related to OHIO-1 (10). We determined the sequences of the bla genes of nine isolates of K. pneumoniae producing a penicillinase with an isoelectric point different from 7.6, the pI of the most com...

Recombinant antigenic proteins of Toxoplasma gondii are alternative source of antigens which are easily obtainable for serodiagnosis of toxoplasmosis. In this study, highly antigenic secretory organellar proteins, dense granular GRA2 and GRA3, rhoptrial ROP2, and micronemal MIC2, were analyzed by bioinformatics approach to express as water-soluble forms of antigenic domains. The transmembrane r...

BBackground: We have previously reported that immunization with GRA 2 antigen of Toxoplasma gondii induces protective immunity in CBA /J (H2k) and BALB/c mice (H2d). We aimed to examine whether immunization of a distinct strain of rodent with recombinant dense granule antigens (GRA2) combined with monophosphorryl lipid A (MPL) adjuvant elicits protective immune response against T. gondii. Metho...

Toxoplasma gondii actively invades host cells and establishes a parasitophorous vacuole (PV) that accumulates many proteins secreted by the dense granules (GRA proteins). To date, at least 23 GRA proteins have been reported, though the function(s) of most of these proteins still remains unknown. We targeted gene knockouts at ten GRA gene loci (GRA1-10) to investigate the cellular roles and esse...

Excreted-secreted Ags (ESA) of Toxoplasma gondii (Tg) play an important role in the stimulation of the host immune system in both acute and chronic infections. To identify the parasite Ag(s) involved in the maintenance of T cell-mediated long term immunity, 40 ESA-specific T cell clones were derived from three chronically infected healthy subjects. All the clones were CD4+ and recognized both E...

Toxoplasma gondii sporozoites form two parasitophorous vacuoles during development within host cells, the first (PV1) during host cell invasion and the second (PV2) 18 to 24 h postinoculation. PV1 is structurally distinctive due to its large size, yet it lacks a tubulovesicular network (C. A. Speer, M. Tilley, M. Temple, J. A. Blixt, J. P. Dubey, and M. W. White, Mol. Biochem. Parasitol. 75:75-...

Cats are the only definitive hosts of Toxoplasma gondii and constitute an essential source of infection to all warm blooded animals and humans. Diagnosis of T. gondii infection in cats is fundamental for proper management and control of infection in humans and animals. In the current study, we have evaluated the diagnostic performance of tachyzoite lysate antigen (TLA) and different T. gondii r...