Table 1: The response of CNS-resident cells to Toxoplasma gondii infection.

Brain cell typeParasite stageActivityReference

NeuronTachyzoiteParasites can encyst in neurons[75]
NeuronTachyzoiteInfection induces cytokine and chemokine production; stimulated neurons are unable to inhibit parasite growth[121]
NeuronBradyzoiteNeurons containing parasite cysts avoid scrutiny by CD8+ T cells[89]
Neuron, microgliaTachyzoiteMurine Nramp1−/− models are affected in stress response and mortality following Toxoplasma gondii infection[122]
MicrogliaTachyzoite, bradyzoiteMicroglial cells are preferentially infected, but most effectively inhibit parasitic growth within CNS cells[25]
MicrogliaTachyzoiteUpon Toxoplasma infection, microglia produce IL-1 beta, IL-10, and tumor necrosis factor-alpha[123]
Microglia, endotheliumTachyzoiteMurine model infection induce an upregulation of CD200R & CD200, which control CNS inflammation[124]
Microglia, astrocyteTachyzoiteInfection downregulates MHC class II expression[125]
MicrogliaTachyzoiteToxoplasmic encephalitis induces IL-12p40, iNOS, IL-1beta, TNF-alpha largely due to CD8+ T cell interaction. MHC classes I and II, ICAM-1, and leukocyte function-associated antigen-1 are also upregulated[126]
EndotheliumTachyzoiteToxoplasmic encephalitis induces vascular cell adhesion molecule, ICAM-1, and MHC classes I and II. Induction depends on IFN-gamma receptor[127]
EndotheliumTachyzoite Infection induces ICAM-1, IL-6, and MCP-1
Induction levels vary depending on parasite strain
Astrocyte, neuronTachyzoiteAstrocytes are preferentially infected compared to neurons[75]
Astrocyte, microgliaTachyzoiteIntracellular infection reduces expressed MHC II[125]
AstrocyteTachyzoiteInterferon-gamma-activated indoleamine 2,3-dioxygenase (IDO) induction inhibits parasite growth[128]
AstrocyteTachyzoiteIFN- gamma induced parasite growth inhibition is independent on reactive oxygen intermediates[129]
AstrocyteTachyzoite, bradyzoiteTissue Inhibitor of Metalloproteinases-1 (TIMP-1) is induced by infection[85]
AstrocyteTachyzoiteAutophagy may be involved in the elimination of the degraded parasite material from the astrocyte host cell cytoplasm[79]
AstrocyteTachyzoiteIGTP is required for IFN-gamma-induced inhibition of parasite growth[130]