Dr. Tamara Zietek presented her work on advanced 3D live cell imaging in intestinal organoids, highlighting the potential of non-animal technologies in biomedical research. With a background in nutritional physiology and intestinal absorption, Dr. Zietek transitioned from animal models to human-based organoid systems, which she considers superior for studying gut physiology and drug-nutrient interactions. As an expert for Doctors Against Animal Experiments, her mission includes promoting scientifically robust, ethical alternatives to animal testing.
Her research focuses on nutrient sensing and hormone secretion in the intestine, particularly involving enterocytes and enteroendocrine cells. These cells express transporters like PEPT1 and SGLT1, which facilitate nutrient uptake and trigger the release of hormones such as GLP-1 and GIP—critical regulators of insulin and glucose homeostasis.
A key innovation in her work is the development of fluorescent live-cell imaging within three-dimensional human intestinal organoids. This technique, which required overcoming the structural complexity of organoids, utilizes calcium-sensitive (Fura-2) and pH-sensitive (BCECF) dyes to visualize intracellular signalling in real time. The imaging system allows detection of transporter activity, hormone secretion, and even drug-induced acidification at a cellular level.
Zietek demonstrated specific responses to substrates and inhibitors, validating transporter functions and revealing cell-specific calcium responses—especially in rare enteroendocrine cells. Her group also pioneered the use of this platform to study drug absorption mechanisms and intracellular changes associated with various pharmacological agents.
Beyond her lab work, Dr. Zietek leads the NAT (Non-Animal Technologies) database initiative, offering a growing, open-access resource cataloguing validated human-based methods across biomedical fields.
She concluded by inviting attendees to the upcoming MPS World Summit, underlining the importance of international collaboration in advancing human-relevant research models.
