The CD40/CD40 Ligand Interaction Is Required for Resistance to Toxoplasmic Encephalitis

The CD40/CD40 ligand interaction is required for resistance to toxoplasmic encephalitis.

Since the CD40/CD40 ligand (CD40L) interaction is involved in the regulation of macrophage production of interleukin 12 (IL-12) and T-cell production of gamma interferon (IFN-gamma), effector cell functions associated with resistance to Toxoplasma gondii, the role of CD40L in immunity to this parasite was assessed. Infection of C57BL/6 mice with T. gondii results in an upregulation of CD40 expr...

Toxoplasmic Encephalitis

Toxoplasmic encephalitis on positron emission tomography

A 31-year-old woman presented with a 2-day history of rightsided weakness, numbness and paresthesia. She was diagnosed with acquired immunodeficiency syndrome (AIDS) 8 months before. Her most recent CD4 count was 19 cells/cmm and her viral load was 15,000 copies/mL, and she reported taking antiretroviral therapy plus prophylactic trimethoprim-sulfamethoxazole and azithromycin. Analysis of her c...

Genetically Resistant to the Disease Toxoplasmic Encephalitis in BALB/c Mice Cells Is Required for Prevention of Perforin-Mediated Cytolytic Activity, of T Gamma Interferon Production, but Not

Gamma interferon production, but not perforin-mediated cytolytic activity, of T cells is required for prevention of toxoplasmic encephalitis in BALB/c mice genetically resistant to the disease.

We previously showed the requirement of both T cells and gamma interferon (IFN-gamma)-producing non-T cells for the genetic resistance of BALB/c mice to the development of toxoplasmic encephalitis (TE). In order to define the role of IFN-gamma production and the perforin-mediated cytotoxicity of T cells in this resistance, we obtained immune T cells from spleens of infected IFN-gamma knockout (...