Node 4, the lab

Gut-on-Chip Lab

A living simulation of the gut–brain axis, and a preview of the kind of model I want to build. Bacteria in the gut channel make butyrate or release LPS, molecules cross a porous barrier, and the neurons below mature, wire up, or pull back depending on what gets through.

Device RR-01

Lab v1

Swipe sideways to see the whole chip.

Good bacteria 0 Bad bacteria 0 Butyrate crossed 0 Neurons fired 0 Synapses 0 Network Maturing Brain channel: butyrate LPS

Tap the gut channel to add

Interventions

Conditions

Flow Barrier leakiness

Run

Simplified model. Good bacteria (like butyrate-producing Firmicutes) make short-chain fatty acids such as butyrate, which help neurons mature: longer, more branched dendrites and new synapses. Bad bacteria (gram-negative pathobionts) release endotoxin (LPS). An intact barrier keeps most LPS out, but when it leaks, LPS gets through, inflammation sets in, neurites pull back, and synapses are pruned. Fiber feeds the good bacteria. Antibiotics thin out both kinds, so butyrate drops too. Tap a neuron to fire it.

Try this

Grow a healthy network. Press Add fiber a few times and watch synapses form between mature neurons.
Cause dysbiosis. Add bad bacteria and raise barrier leakiness. Watch the network become inflamed and lose synapses.
Recover. Lower leakiness, add good bacteria and fiber, and see how long the network takes to come back.

In development

This lab keeps growing. Ideas on the bench:

A barrier that repairs itself with butyrate
Mucus layer and Akkermansia
Immune cells and cytokines
Blood–brain barrier compartment
Vagus nerve shortcut
Diet: fiber vs. sugar
Challenges

Lab v1
Good and bad bacteria, neuron maturity, synapse formation and pruningPlus barrier leakiness, fiber, antibiotics, and speed controls.