Principal Investigator:John Geibel, MD, DSc, MSc, AGAF, FRSM, Director
Director and Fellow
The John B. Pierce Laboratory
Surgery and Cellular & Molecular Physiology
Yale School of Medicine
American Gastroenterology Association Fellow
Fellow of the Royal Society of Medicine
Our primary focus is on real time monitoring of ion transport mechanisms in epithelia, using high-resolution microscopy. One of the crucial problems facing all epithelial cells is the control of the intracellular milieu. In an effort to maintain ionic homeostasis, epithelial cells have devised a variety of ion channels, transport proteins, and carriers to regulate and maintain the intracellular ionic concentrations. To further understand how ions are transported in epithelial cells, we have developed a variety of optical techniques to continuously monitor intracellular ionic concentrations in real time. Using high-resolution video or confocal microscopy we are presently able to monitor intracellular Ca2+, Na+, K+, Cl-, pH, and membrane potential. We are currently investigating various aspects of renal tubule and gastric tissue ion transport in intact renal tubules and gastric glands. We also are characterizing the secretory and reabsorptive properties of the colonic crypt, with a special focus on diarrheal disease.
Specialized Terms: Gastric Acid Secretion; Colonic Fluid Transport; Renal Physiology; Intracellular Ion Activity Measurements; Calcium Sensing Receptor; Diarrheal disease; electrophysiology; CFTR; AMPKinase volume regulation
We are focused on 3 main areas; gastric ion transport in health and disease, intestinal ion transport in health and disease, and 3DBioprinting. For gastric ion transport we are focusing on means to modulate acid secretion and reverse erosion. We use a combination of natural products and biochemical modifications to treat acid disease at the cellular level. For studies of intestinal ion transport, we are focusing on how the calcium sensing receptor(CaSR) can modulate fluid transport during toxin induced diarrhea. We are also looking at nanoparticle therapies for Ulcerative Colitis. In addition we are investigating means to prevent ischemic injury by activating ionic pathways using the AMPKinase. Finally we are trying to prevent IBD/IBS associated epithelial injury in the gut by CaSR activation using nutraceuticals.
For the 3DBioprinting area we are developing replacement conduits that can be used for the aorta, the inferior vena cava, and also as small and large intestine repair tool. Along with this research we are now examining the potential for intestinal elongation using a 3D printed replacement.
Below are some photos of our latest 3DBioprinter systems with our technicians actively generating tissue samples.
- Yale Press: “Living Cells as Printer Ink: Jet bioprinting opens new possibilities for medical treatment”
- Geibel Lab in Yale News
- We May Be Able to Stop Common Lethal Secretory Diarrhea…
Yale College ’22
Master’s Candidate, Germany
Sr. Yale College