Thread by @NateB_Panic

Scientists have found what they call 'the master regulator' of the immune system in the human brain. If it holds up it's a stunning discovery that could transform treatments for autoimmune disease and post-viral illnesses. What did they find, and how?🧵

They found that neurons in a part of the brain known as the caudal Nucleus of the Solitary Tract (cNST) fire, or misfire, to produce a balanced or dysregulated immune and inflammatory response. They found, in their own words, “a new brain circuit.”

A circuit that helps determines how your body responds to infection. A response that determines if you live, die, or develop a post-viral or autoimmune condition. Let’s delve in to the detail.

The cNST is the big first stop for info being sent from the body to the brain, info carried to the brain by the vagus nerve which connects the gut to the brain. When immune cells in the body are activated by infection or injury the vagus nerve transmits information to the cNST

The cNST first processes then passes on this information to cells throughout the body, telling it how to respond to infection. Should it produce a small amount of inflammation to knock out the invader? A large dose?

To make the discovery, researchers gave mice a bacterial compound to stimulate an immune response which activated neurons in the cNST. On witnessing the activation, they tried blocking the neurons in the cNST from sensing the information sent by the vagus nerve

The researchers reckoned if they blocked neurons in the cNST from sensing this information it would affect the immune response. It did. Inhibiting the neurons “dramatically increased the pro-inflammatory response and decreased the anti-inflammatory response" in the body

The researchers called this a “remarkable” discovery. Stopping the neurons from responding to the signals sent by the vagus nerve created, in words of the researchers, “a run-away, out-of-control inflammatory response.”

They said the results suggest the cNST functions as a “homeostatic neural control of peripheral immune responses.” The cNST as the control knob for the immune system. The role of the vagus nerve is also key

Long postulated as critical to the immune system, blocking the ability of the vagus nerve to transfer information to the cNST meant the neurons didn’t respond to the activation of the immune cells elsewhere in the body

Tise confirms the vagus nerve as a critical component of the immune system, in essence the telephone line that enables the body to talk to the brain to tell it to activate an inflammatory response, and what type of response

Then, rather than suppressing the neurons, they tried artificially activating them to see if it would produce the opposite response – a substantially reduced pro-inflammatory response and a substantially increased anti-inflammatory response

It did.

“Modulating the activity of these brainstem neurons can bidirectionally regulate peripheral inflammation.”

Bidirectionally? Yep.

“Anti and pro-inflammatory cytokines activate two discrete non-overlapping populations of vagal sensory neurons.”

There are two knobs!

“One line carries anti-inflammatory signals and….enhances the anti-inflammatory response...the other helps tune down the pro-inflammatory response.” This makes it easy to visualise how dysregulated immune responses happen and how they can provoke ongoing health issues

You’re infected by a virus or pathogen, the two dials start moving in response to the information sent by the vagus nerve, they start rotating to find the right combination to unlock the sweet spot in the immune response. Up, down, up, down, searching, searching.

Then instead of aligning of 5, unlocking an optimal immune response, they get stuck. Stuck in the wrong locations.

One dial is up at 9, one is down at 2.

The immune response has been compromised.

Inflammatory molecules are now being pumped out to the wrong locations.

Maybe parts of your body that actually need some inflammation aren’t getting enough. Things are all out of whack. And they stay out of whack. Some people’s dials might be a little out of sync, others a long way out of sync. Hence mild post viral issues or severe post viral issues

This is also why every infection, especially with a full-body virus like SarsCov2 that can access so many organs, is such a roll of the dice. We have to bank on those dials lining up on the immune sweet spot every single time

Now, the exciting thing is that once they had made these discoveries, the researchers played around with the dials, with this newly-found neuronal system. And they restored dysregulated immune balance! (in mice)

Some mice were saved from a lethal dose of bacterial compound by artificially manipulating the neuronal system, others were exposed to inflammatory bowel disease but were protected from disease development

More in here, including caveats (yes, it's mice). But in a world devoid of good news, there is no need to downplay this: it’s huge.
donotpanic.news/p/scientists-j…