Table 1 Summary of evidence for neuroinflammation in ASD

Brain tissues obtained from autopsy

Neuroinflammation observed in cerebral cortex and white matter, and cerebellum of ASD patients by immunocytochemical methods and cytokine profiling

[56]

CSF of living ASD patients

Cytokine profiling showed neuroinflammation

[56]

Brain tissues from the dorsolateral prefrontal cortex of ASD individuals

Microglia activation reported in individuals as young as < 6 years of age with morphological changes in microglia

[57]

PET scans using brain microglia radiotracer

Findings suggest an increased microglia activation in multiple regions of the brain of subjects with ASD

[58]

PET scan for TSPO

Lower expression of TSPO in several brain regions of patients with ASD when compared with control

[59]

MR–PET scan of [18F]FEPPA (specific ligand for TSPO)

Significantly lower [18F]FEPPA total volume of distribution in ASD patients when compared to the control

[60]

Brain tissues/blood hormone level of mice

Mice showed increased blood cortisone levels, increased microglia in hippocampus and increased proinflammatory cytokines in cerebellum when compared with control group

[61]

Brain of MIA mice and offspring of MIA mice

MIA in pregnant mice led to abnormal cortical development in offspring and increased IL-17a mRNA expression in foetal brain mediated via maternal IL-17a pathway

[62]

Serum, plasma, CSF and brain of patients with ASD

Increased levels of proinflammatory substances like interleukins, chemokines and osteopontin, TNF-α, IF- γ and growth factors

[63]