For Salmonella and many other disease-causing bacteria that find their way into our bodies, infection begins with a poke. That’s because these bad bugs are equipped with a needle-like protein filament that punctures the outer membrane of human cells and then, like a syringe, injects dozens of toxic proteins that help them replicate.
Cammie Lesser at Massachusetts General Hospital and Harvard Medical School, Cambridge, and her colleagues are now on a mission to bioengineer strains of bacteria that don’t cause disease to make these same syringes, called type III secretion systems. The goal is to use such “good” bacteria to deliver therapeutic molecules, rather than toxins, to human cells. Their first target is the gastrointestinal tract, where they hope to knock out hard-to-beat bacterial infections or to relieve the chronic inflammation that comes with inflammatory bowel disease (IBD).
Tags: antibodies, bacteria, bacterial toxins, bioengineering, digestion, drug delivery, drug delivery vehicles, E. coli, Escherichia coli, gastrointestinal tract, IBD, inflammation, inflammatory bowel disease, intestine, microbiology, NIH Director’s 2016 Transformative Research Award, probiotics, secretion system, Shigella, single-domain antibodies, synthetic biology, technology, type III secretion systems
Microbes that live in dirt often engage in their own deadly turf wars, producing a toxic mix of chemical compounds (also called “small molecules”) that can be a source of new antibiotics. When he started out in science more than a decade ago, Michael Fischbach studied these soil-dwelling microbes to look for genes involved in making these compounds.
Eventually, Fischbach, who is now at the University of California, San Francisco, came to a career-altering realization: maybe he didn’t need to dig in dirt! He hypothesized an even better way to improve human health might be found in the genes of the trillions of microorganisms that dwell in and on our bodies, known collectively as the human microbiome.
Tags: 2016 NIH Director’s Pioneer Award, analytical chemistry, antibiotics, bacteria, biochemistry, biofilm, digestion, gastrointestinal disease, gastrointestinal tract, genetic engineering, genetics, GI tract, gut, gut bacteria, gut microbiome, heart disease, microbes, microbiome, microbiota, microorganisms, obesity, probiotics, small molecules, synthetic gut community
When Nancy Allbritton was a child in Marksville, LA, she designed and built her own rabbit hutches. She also once took apart an old TV set to investigate the cathode ray tube inside before turning the wooden frame that housed the TV into a bookcase, which, by the way, she still has. Allbritton’s natural curiosity for how things work later inspired her to earn advanced degrees in medicine, medical engineering, and medical physics, while also honing her skills in cell biology and analytical chemistry.
Now, Allbritton applies her wide-ranging research background to design cutting-edge technologies in her lab at the University of North Carolina, Chapel Hill. In one of her boldest challenges yet, supported by a 2015 NIH Director’s Transformative Research Award, Allbritton and a multidisciplinary team of collaborators have set out to engineer a functional model of a large intestine, or colon, on a microfabricated chip about the size of a dime.
Tags: 2015 NIH Director’s Transformative Research Award, bioengineering, colon, colon on a chip, crypts, diet, digestion, gastrointestinal disease, gastrointestinal tract, genomics, hydrogel, immunity, intestinal crypt, intestine, large intestine, microbiome, organoids, regenerative medicine, simulacrum, stem cell technology, stem cells, tissue chips