More evidence of direct #SARSCoV2 brain invasion points out that the neurological, cognitive, and psychiatric symptoms associated with COVID-19 might not only be driven by circulating inflammatory cytokines and indirect neuroinflammation.
@Gaudinlab just published a study examining human brain samples from individuals with COVID-19, cerebral organoids, and organotypic culture of human brain explants.
Their results are similar to what I also observed in the monkey brain:
The primary neural target of SARS-CoV-2 is mostly found to be neuronal, although other neural cell types have been reported to show some degree of permissivenes."
This is why SARS-CoV-2 will never be like the Flu. Show me an influenza strain that directly infects neurons in the primate brain.
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Alzheimer’s disease (AD) is a devastating condition with no effective treatments, and promising findings in rodents constantly failing to translate into successful therapies for patients. To develop an AD model closer to humans, we used rhesus monkeys, and targeted the vulnerable entorhinal cortex, delivering a dual tau mutation into the region. During a 3 or 6 months period, we longitudinally collected all possible samples for biomarker analysis:
spinal fluid, plasma, structural MRI, Tau PET Scan and combined these data with high-resolution microscopy analysis of brain tissue. 2/5
Related to microscopy, we used a comprehensive panel of antibodies to characterize the profile of Tau-induced pathology in neurons of the Entorhinal-Hippocampus region. 3/5
It's #FluorescentFriday!
What happens in the brain during normal aging?
While most neurons will not shrink, they will lose synapses, the connections between different neurons, which can affect learning and memory.
But how do we take these images from primates? (1/5)
Since genetic manipulations are hard to perform in primates, we apply an electric current to inject fluorescent dye into individual neurons in this type of image. Check the video below: (2/5)
Microinjection of dye allows us to identify the spines, small protrusions on a neuron that receives input from another neuron. Spine size and shape are linked to memory and learning, and some types are highly vulnerable to normal aging. (3/5)