Vargas DL, Nascimbene C, Krishnan C, Zimmerman AW, Pardo CA, Neuroglial activation and neuroinflammation in the brain of patients with autism. Ann Neurol. 2005 Jan;57(1):67-81.
http://www.ncbi.nlm.nih.gov/pubmed/15546155
From a post criticizing the Burbacher study, NotMercury writes:
In an earlier study, Burbacher describes the effects of high dose mercury toxicity and specific changes within the very types of brain cells studied by the Vargas group. He reports an increase in the number of microglial cells and a steady decline in the numbers of astrocytes. These findings are completely inconsistent with data from both Vargas et al. and Rezaie et al. studies. Number of microglia does not reflect state of activation.
From a review of the bases for "biomedical" treatments for autism:
Immune system abnormalities are inferred from increased cytokine levels in post mortem studies of autistic subjects. But the researchers themselves dispute this interpretation of their work. A key work is Vargas, 2005 that is often cited as proof that inflammation as a result of immune system abnormalities is implicated in the aetiology of autism. But the senior author in this study Carlos A. Pardo-Villamizar cautiously points out in a press release (Science Blog 2004) that, “it is not yet clear whether [the immune activation] is destructive or beneficial or both.” On the question of treatments he says that “much more research would be needed to establish the validity of this approach.”
In 2008, the anchor author Pardo wrote as an expert witness in the Autism Omnibus trial:
These findings are inconsistent with the hypothesis of a potential toxic effect on astrocytes by neurotoxins or toxic material.
and
Another issue that is important to clarify is the notion that neuroinflammatory responses mediated by innate responses and neuroglial activation are directly associated with injury. At present, we are not able to conclude that these neuroglial reactions are deleterious for the central nervous system. These reactions may invoke anti-inflammatory and repairing processes as demonstrated in our study in which one potent anti-inflammatory cytokine, the transforming growth factor -1 (TGF1) was significantly present in all areas of the brain. Other members of the same family of proteins (TGF2) were also present in the cerebrospinal fluid. So, it is erroneous to assign an exclusive deleterious or injury effect of these neuroglial responses in the CNS.
The idea of autism as mercury poisoning goes something like this: The thimerosal (that was removed from vaccines in 2001) gets changed to ethyl mercury which deposits mercury ions in the brain, causing neuroinflamation which causes autism.
There are many flaws in that chain of reasoning but a remarkable one is that the few world experts on autism and neuroinflammation the disagree with the contention that neuroinflamation in autistic brains is due to neurotoxins.
Does this paper "demonstrate that vaccines can cause autism"? No.
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