FW: Great paper on retroviral infection of brain

[Guest guest]

Incredibly interesting

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2665180/?tool=pubmed

.... The innate and adaptive responses to HIV and SIV infection in the CNS

play a large role in the course of CNS disease, but are less well

characterized than the responses found in the blood and lymphoid organs.

Virus enters the brain within two weeks of infection, and if an effective

systemic immune response occurs, becomes relatively quiescent until

end-stage disease, when in a fraction of people and animals pronounced

neurological symptoms can occur accompanied by encephalitisŠ

ŠSince HIV/SIV in the brain is largely derived from macrophages, we

examined whether the infectious phenotype of virions produced in macrophages

might differ from those produced in T cells. Such virions showed no

difference in genomic RNA/Gag or Env/Gag ratios, and sequence analysis

revealed no mutations resulting from production in the different cell types.

Infectivity assays, using a number of in vitro and in vivo derived targets,

revealed a significantly higher infectivity of macrophage derived virions.

Š.The 3 to 10 fold greater infectivity of macrophage derived virions,

amplified over even a few rounds of viral replication, can result in an

enormous increase in the spread of infection in the brain, where macrophages

are the primary source and target for HIV infection.

ALSO: ... Interestingly, our recent work in monkeys reveals that both plasma

osteopontin, and one of its receptors on monocytes, CD44v6, are increased in

animals developing SIV encephalitis, and that in HIV-infected people,

osteopontin levels increase proportionally to the severity of CNS

dysfunction.

Has anyone looked into plasma osteopontin or CD44v6 levels in autism?? (I

could not find any info/research out there). It would be highly interesting

if results positive!!

FINALLY:

We have utilized a number of testing modalities, Š these indeed revealed

that CNS ABNORMALITIES ARE COMMON IN OTHERWISE ASYMPTOMATIC SIV-infected

rhesus monkeys. Š Interestingly, analysis of the circadian rhythms of body

temperature and movement in monkeys that developed SIV encephalitis revealed

impairments in circadian rhythms that preceded clinical symptoms

Isn't 2-3 week period (at most) what people report re regression after

vaccination, i.e. enough for the virus to enter the brain and spread there?

Natasa