Morgridge Institute for Research

Collagen fibrils encircling a mouse tumor, courtesy of the Bartels Lab. Collagen is...

>> The most abundant protein in the human body.

>> The main component of the extracellular matrix.

>> Remodeled and deposited in the extracellular matrix at abnormally high levels during cancer.

>> Showing up as the green structures you see here, captured by the Bartels Lab with a technique called second harmonic generation imaging.

Critically, second harmonic generation doesn't perturb the biological system under the microscope. Instead it relies on the natural structural properties of material like collagen (and others, from myosin to cellulose to potato starch). When two photons with the same frequency interact with these materials, they "combine" to generate a new photon with twice the energy.

That energy can appear as visible light — in this case, illuminating the tumor environment. 🌈💡🔬

Image credit: Dave Smith.