Researchers at Tufts University School of Medicine and the Graduate School of Biomedical Sciences (GSBS) have unveiled a groundbreaking three-dimensional model designed to study the regeneration of nerve tissue within the nose. This technological advancement has led to a significant discovery: a specific type of stem cell, previously dismissed by the scientific community as largely dormant, appears to play a vital, active role in preserving the human sense of smell.<\/p>\n
The findings, recently published in the journal Cell Reports Methods<\/em>, offer new insights into why the sense of smell often diminishes due to viral infections, exposure to environmental toxins, or the natural process of aging. By utilizing an innovative mouse-derived organoid model, the research team has successfully mapped the complex cellular communication that sustains our ability to perceive scents, potentially opening the door to new therapeutic interventions for those suffering from olfactory loss.<\/p>\n Unlike the neurons found in the central nervous system, which are notoriously difficult to repair once damaged, the sensory neurons within the nasal cavity possess a remarkable, lifelong capacity for regeneration. This constant renewal is a necessity, as these cells are frequently subjected to harsh conditions, including exposure to pollutants, pathogens, and environmental irritants.<\/p>\n However, this resilience is not infallible. When the nasal epithelium is overwhelmed\u2014whether by the inflammatory storm of a COVID-19 infection, long-term exposure to toxic substances, or the physiological decline associated with senescence\u2014the regenerative process can falter. This breakdown often results in anosmia (a complete loss of smell) or hyposmia (a partial reduction in the ability to smell). Because the sense of smell is intrinsically linked to quality of life, nutrition, and even safety, understanding the mechanisms behind this failure has become a high-priority area of research in the post-pandemic era.<\/p>\n To better investigate these cellular dynamics, the Tufts research team developed a three-dimensional olfactory tissue mouse model, or organoid. This "mini-organ" system mimics the structure and function of the nasal lining, allowing scientists to observe in real-time how neurons are generated and, crucially, where the process goes wrong.<\/p>\n The study centers on the interaction between two primary types of stem cells found in the nose: horizontal basal cells (HBCs) and globose basal cells (GBCs). Traditionally, the scientific consensus held that GBCs were the primary drivers of neurogenesis, while HBCs were viewed as a dormant "reserve" pool, waiting to be activated only during catastrophic tissue injury.<\/p>\n Brian Lin, a research assistant professor in the Department of Developmental, Molecular and Chemical Biology and senior author of the study, explains that the new model has fundamentally shifted this understanding. "Our research suggests that these two stem cells may be interdependent," Lin notes. "One type that we thought was largely dormant\u2014HBCs\u2014may actually play a crucial role in supporting the production of new neurons and the repair of damaged tissue."<\/p>\n By isolating a specific subpopulation of HBCs marked by the production of the protein KRT5, the team demonstrated that these cells are far from idle. In the organoid environment, these KRT5-positive HBCs were observed actively participating in the formation of new tissue. When researchers selectively depleted these cells from the cultures, the generation of new neurons plummeted, confirming that these once-overlooked cells are essential architects of the regenerative process.<\/p>\n In addition to identifying the role of HBCs, the research team utilized the model to explore the effects of age on olfactory regeneration. By growing cells from mice of varying ages, the researchers observed a clear, progressive decline in the capacity to generate new neurons as the biological age of the tissue increased.<\/p>\n "We found a decline in the ability of the older mice cells to generate new neurons," Lin says. "We think this is due to a decrease in the GBC population as we age, but we need to do more work to test this hypothesis and, if so, develop ways to rejuvenate them." This line of inquiry is particularly promising, as it suggests that if scientists can identify the specific factors that trigger the depletion or dysfunction of GBCs, they might eventually develop pharmaceutical or biological interventions to "rejuvenate" the aging nose.<\/p>\n A significant achievement of this project was the development of a model designed for accessibility. Juliana Gutschow Gameiro, the lead author of the study and a former Ph.D. student at GSBS who joined the team from the State University of Londrina in Brazil, focused her efforts on ensuring the model was efficient and cost-effective.<\/p>\n "Because loss of smell is associated with COVID-19, as well as with Parkinson’s disease and other conditions, a much larger number of researchers from a variety of different fields have begun researching olfactory epithelial cells in the last few years," Lin says. By creating a model that does not require prohibitive levels of funding or highly specialized, rare equipment, the team hopes to democratize the study of olfactory neurogenesis. "We wanted to develop an easy-to-use model so that non-stem cell biologists and those working in labs with limited resources could use it to better understand how olfactory neurons regenerate and what happens that causes that process to diminish or fail completely."<\/p>\n The long-term objective of the Tufts team is to translate the success of their mouse-tissue model into a human organoid. Such a tool would be invaluable for pre-clinical drug screening, allowing researchers to test the efficacy of potential treatments on human olfactory cells without the ethical and logistical challenges of using whole animal models or unreliable cell cultures.<\/p>\n Organoids have already transformed the study of organs like the lungs and kidneys, providing a more accurate representation of human biology than traditional flat-dish cultures. However, the nose presents a unique set of challenges. "It’s challenging to get pure olfactory tissue from humans," Lin explains. Currently, the standard procedure for collecting such tissue involves anesthetizing a patient and using a brush\u2014similar to those used in COVID-19 diagnostic tests\u2014to retrieve cells from deep within the nasal cavity.<\/p>\n The primary hurdle in developing a human-specific organoid lies in the biological complexity of these samples. When researchers collect cells using the brushing method, they inevitably gather a mixture of respiratory stem cells and olfactory stem cells. Distinguishing between the two, and then coaxing the delicate olfactory stem cells to thrive in a laboratory environment, is a task that remains at the frontier of current medical research.<\/p>\n The team\u2019s next phase of investigation will focus on overcoming this barrier by developing a simple, inexpensive technique to isolate human olfactory stem cells. If they succeed, the implications for patients are profound. Whether a person has lost their sense of smell due to a virus, neurodegenerative disease, or the natural process of aging, the ability to study their specific cellular response in a lab could lead to personalized regenerative therapies.<\/p>\n By proving that the "dormant" cells of the nose are actually vital, active players in tissue repair, the Tufts researchers have not only added a new chapter to our understanding of sensory biology but have also provided a robust foundation for future clinical breakthroughs. As the team moves toward the creation of human organoids, their work stands as a testament to the power of accessible, innovative science in addressing one of the most persistent and life-altering sensory deficits in modern medicine.<\/p>\n","protected":false},"excerpt":{"rendered":" Researchers at Tufts University School of Medicine and the Graduate School of Biomedical Sciences (GSBS) have unveiled a groundbreaking three-dimensional model designed to study the regeneration of nerve tissue within the nose. This technological advancement has led to a significant discovery: a specific type of stem cell, previously dismissed by the scientific community as largely […]<\/p>\n","protected":false},"author":1,"featured_media":2423,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[650],"tags":[2672,4405,652,451,2485,656,2673,666,1647,658,659,2671,270,651],"class_list":["post-2424","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-health-and-wellness","tag-cells","tag-dimensional","tag-fitness","tag-health","tag-hidden","tag-model","tag-restoring","tag-reveals","tag-role","tag-sense","tag-smell","tag-stem","tag-three","tag-wellness"],"_links":{"self":[{"href":"https:\/\/xesi.net\/index.php?rest_route=\/wp\/v2\/posts\/2424","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/xesi.net\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/xesi.net\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/xesi.net\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/xesi.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=2424"}],"version-history":[{"count":0,"href":"https:\/\/xesi.net\/index.php?rest_route=\/wp\/v2\/posts\/2424\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/xesi.net\/index.php?rest_route=\/wp\/v2\/media\/2423"}],"wp:attachment":[{"href":"https:\/\/xesi.net\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=2424"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/xesi.net\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=2424"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/xesi.net\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=2424"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}The Regenerative Power of the Nasal Cavity<\/h3>\n
Unlocking the Secret Life of Stem Cells<\/h3>\n
The Impact of Aging<\/h3>\n
An Accessible Tool for Global Research<\/h3>\n
From Mice to Humans: The Path Ahead<\/h3>\n