TY - JOUR
T1 - Strain-specific pre-existing immunity
T2 - A key to understanding the role of chronic Toxoplasma infection in cognition and Alzheimer's diseases?
AU - Xiao, Jianchun
AU - Savonenko, Alena
AU - Yolken, Robert H.
N1 - Funding Information:
This work was supported by the Stanley Medical Research Institute (SMRI).
Publisher Copyright:
© 2022 The Authors
PY - 2022/6
Y1 - 2022/6
N2 - Toxoplasma exposure can elicit cellular and humoral immune responses. In the case of chronic Toxoplasma infection, these immune responses are long-lasting. Some studies suggest that pre-existing immunity from Toxoplasma infection can shape immune responses and resistance to other pathogens and brain insults later in life. Much evidence has been generated suggesting Toxoplasma infection may contribute to cognitive impairment in the elderly. However, there have also been studies that disagree with the conclusion. Toxoplasma has many strain types, with virulence being the most notable difference. There is also considerable variation in the outcomes following Toxoplasma exposure ranging from resolved to persistent infection. Therefore, the brain microenvironment, particularly cellular constituents, differs based on the infecting strain (virulent versus hypovirulent) and infection stage (resolved versus persistent). Such difference might play a critical role in determining the outcome of the host on subsequent challengings to the brain. The ability of Toxoplasma strains to set up distinct stages for neurodegenerative pathology through varying degrees of virulence provides unique experimental tools for characterizing these pathways.
AB - Toxoplasma exposure can elicit cellular and humoral immune responses. In the case of chronic Toxoplasma infection, these immune responses are long-lasting. Some studies suggest that pre-existing immunity from Toxoplasma infection can shape immune responses and resistance to other pathogens and brain insults later in life. Much evidence has been generated suggesting Toxoplasma infection may contribute to cognitive impairment in the elderly. However, there have also been studies that disagree with the conclusion. Toxoplasma has many strain types, with virulence being the most notable difference. There is also considerable variation in the outcomes following Toxoplasma exposure ranging from resolved to persistent infection. Therefore, the brain microenvironment, particularly cellular constituents, differs based on the infecting strain (virulent versus hypovirulent) and infection stage (resolved versus persistent). Such difference might play a critical role in determining the outcome of the host on subsequent challengings to the brain. The ability of Toxoplasma strains to set up distinct stages for neurodegenerative pathology through varying degrees of virulence provides unique experimental tools for characterizing these pathways.
KW - Alzheimer's disease (AD)
KW - Exacerbate
KW - Hypovirulent strain
KW - Immunosuppression
KW - Low-grade inflammation
KW - Pre-existing immunity
KW - Protection
KW - Subsequent brain insults
KW - Toxoplasma gondii (T. gondii)
KW - Variable outcomes following infection
KW - Virulent strain
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U2 - 10.1016/j.neubiorev.2022.104660
DO - 10.1016/j.neubiorev.2022.104660
M3 - Review article
C2 - 35405182
AN - SCOPUS:85129400570
SN - 0149-7634
VL - 137
JO - Neuroscience and Biobehavioral Reviews
JF - Neuroscience and Biobehavioral Reviews
M1 - 104660
ER -