May 09, 2014 A signal from Transit-Amplifying Cells (TACs) activates stem cells in the hair follicle, researchers have found. Both types of cells appear in green (top), with TACs clustered lower down. The researchers identified the signal as Sonic Hedgehog. In experiments, such as this one (bottom), they disabled the signal, interfering with hair growth and regeneration.
(Phys.org) Stem cells switch off and on, sometimes dividing to produce progeny cells and sometimes resting. But scientists don't fully understand what causes the cells to toggle between active and quiet states.
New research in Elaine Fuchs' Laboratory of Mammalian Cell Biology and Development focused on stem cells in the hair follicle to determine what switches them on. The researchers found cells produced by the stem cells, progeny known at Transit-Amplifying Cells or TACs, emit a signal that tells quiet hair follicle stem cells to become active.
"Many types of mammalian stem cells produce TACs, which act as an intermediate between the stem cells and their final product: fully differentiated cells in blood, skin and elsewhere," says Ya-Chieh Hsu, who conducted the research while as a postdoc in the lab and will soon move to Harvard University. "In the past, TACs were seen as a population of cells that sat by passively cranking out tissues. No one expected them to play a regulatory role."
Hsu and Fuchs went a step further to identify the signal sent out by the TACs. They pinpointed a cell-division promoting protein called Sonic Hedgehog, which plays a role in the embryonic development of the brain, eyes and limbs.
Stem cells are medically valuable because they have the potential to produce a number of specialized cells suitable for specific roles. Stem cells' production of these differentiated cells is crucial to normal maintenance, growth and repair. Many tissues have two populations of stem cells: one that divides rarely, known as the quiescent stem cells, and another that is more prone to proliferate, known as primed stem cells. Regardless of their proliferation frequency, most stem cells in humans do not directly produce differentiated progeny cells; instead, they give rise to an intermediate proliferating population, the TACs.
The hair follicle, the tiny organ that produces a hair, forms a narrow cavity down into the skin. It cycles between rounds of growth, destruction and rest. When entering the growth phase, the primed stem cell population is always the first to divide and generates the TACs clustered lower down in the hair follicle. Primed stem cell proliferation sets the stage for the next round of hair growth, a process which ensures hairs are replaced as they are lost over time. Proliferating TACs produce the hair shaft, as well as all the cells surrounding the hair underneath the skin, which make up the follicle itself.
At the outset, Hsu and Fuchs suspected a role for both the TACs and for Sonic Hedgehog in hair regeneration.
"We noticed that the primed stem cell population gets activated early and makes the TACs, while the quiescent stem cell population only becomes activated once TACs are generated. This correlation prompted us to look for a signal that is made by the TACs. Sonic Hedgehog is that signal, as we went on to demonstrate," explained Fuchs.
In experiments described this week in Cell, Hsu disabled TACs' ability to produce the Sonic Hedgehog protein by knocking out the gene responsible in the hair follicles of adult mice. As a result, the proliferation of hair follicle stem cells and their TACs are both compromised. They further showed that it is the quiescent stem cell population which requires Sonic Hedgehog directly for proliferation.
Read the original here:
Stem cell progeny tell their parents when to turn on
- Immunotherapy Inches Forward in Development of Myeloid Malignancies - OncLive - January 14th, 2021
- Cytovia Therapeutics Partners with National Cancer Institute to Develop Novel Gene-Edited, iPSC-Derived GPC3 CAR NK Cells for the Treatment of Solid... - January 14th, 2021
- Kaleido Biosciences Announces Positive Interim Results of Controlled Study of KB109 in Patients with Mild-to-Moderate COVID-19 - BioSpace - January 14th, 2021
- Doctors Make Medical Breakthrough In Treating Severe Cases Of COVID - CBS San Francisco - January 9th, 2021
- Mana joins the hectic fight against solid tumors with an 'off-the-shelf' candidate angling for an IND this year - Endpoints News - January 9th, 2021
- Versiti Blood Centers and Noodles & Company Serve Up Thanks to Blood Donors - PRNewswire - December 31st, 2020
- Global CAR-T Pipeline Insight Report 2020: Overview, Landscape, Therapeutic Assessment, Current Treatment Scenario and Emerging Therapies -... - December 31st, 2020
- 2020 health care year in review - Crain's Cleveland Business - December 31st, 2020
- The Top 10 FDA Oncology Drug Approvals of 2020 - Curetoday.com - December 31st, 2020
- Gut microbiota: How does it interact with the brain? - Medical News Today - December 31st, 2020
- Numerous Indian American STEM Researchers Named Fellows of American Association for the Advancement of Sciences - India West - December 31st, 2020
- Four years after devastating spinal injury, former St. Paul's football player reunites with caregivers - NOLA.com - December 24th, 2020
- New Combination Therapy Tested By Children's May Offer Hope For Leukemia Patients - WVXU - December 24th, 2020
- Real-time observation helpful in Stem cell for vascular diseases: Study - Hindustan Times - December 21st, 2020
- NurOwn May Be Given to Early ALS Patients in US Who Finished Phase... - ALS News Today - December 21st, 2020
- Follow the Money: Spatial Omics, CAR-NK Cells, AI-Powered Biology - Bio-IT World - December 21st, 2020
- Explained: Process of transporting stem cell from donor to patient for a successful transplant - Firstpost - December 18th, 2020
- Research That Saves Lives: Four COVID-19 Therapies Being Tested at UVA - University of Virginia - December 18th, 2020
- Even if You've Had COVID-19 You Still Need the Vaccine - Healthline - December 18th, 2020
- What Patients With Cancer, Survivors Need to Know About the Emergency Use Authorization of COVID-19 Vaccine - Curetoday.com - December 16th, 2020
- 2020 at the U: The year in review - University of Miami - December 16th, 2020
- Five Mobile County hospitals to get Pfizer vaccine this week - AL.com - December 16th, 2020
- Donor Stem Cell Transplant Improves Survival in Older Patients with Myelodysplastic Syndrome - Cancer Health Treatment News - December 10th, 2020
- Positive Phase 2 Proof-of-Concept Data for Viralym-M and Burden of Disease Data Presented in Oral Presentations at the 62nd American Society of... - December 10th, 2020
- Dr. Kansagra: Quadruplet Therapy for Newly Diagnosed Multiple Myeloma and Combination CAR T-Cell Opportunities - DocWire News - December 10th, 2020
- Silicon Therapeutics Announces Members of Scientific Advisory Board - Business Wire - December 10th, 2020
- Israeli Neurogenesis' NG-01 slows progressive MS by up to 90% in phase II study - BioWorld Online - December 10th, 2020
- ADC Therapeutics Announces Updated Clinical Data on Lead Antibody Drug Conjugate Programs Loncastuximab Tesirine (Lonca) and Camidanlumab Tesirine... - December 10th, 2020
- Magenta Therapeutics Announces Commencement of First Phase 2 Clinical Trial of MGTA-145 for Stem Cell Mobilization, Oral Presentation of MGTA-145... - December 8th, 2020
- Precigen Presents New Data Supporting the Safety, Clinical Activity, Expansion and Persistence of PRGN-3006 UltraCAR-T at the 62nd ASH Annual Meeting... - December 8th, 2020
- ALLO-715, Off-the-Shelf CAR T-Cell Therapy, Produces Early Promise in Multiple Myeloma - Cancer Network - December 8th, 2020
- Rocket Pharmaceuticals Presents Positive Clinical Data from its Fanconi Anemia and Leukocyte Adhesion Deficiency-I Programs at the 62nd American... - December 8th, 2020
- Negrin Shines Light on the Orca-T Story in GVHD - OncLive - December 8th, 2020
- Preliminary Results from NexImmune's Phase 1/2 Trial of NEXI-001 in AML Presented at 62nd ASH Annual Meeting and Exposition - GlobeNewswire - December 8th, 2020
- BeiGene Announces the Approval in China of BLINCYTO (Blinatumomab) for Injection for Adult Patients with Relapsed or Refractory B-Cell Precursor Acute... - December 8th, 2020
- Sutro Biopharma Presents Data from Ongoing Phase 1 Dose-Escalation Study for STRO-001 for the Treatment of B-cell Non-Hodgkin Lymphoma at the 62nd... - December 8th, 2020
- Data from the ANDROMEDA Study Show Hematologic Response for DARZALEX FASPRO (daratumumab and hyaluronidase-fihj) in Newly Diagnosed Light Chain (AL)... - December 8th, 2020
- US FDA Approves Naxitamab for the Treatment of Neuroblastoma - OncoZine - November 29th, 2020
- Coronavirus treatments and vaccines. Here are the latest developments - San Francisco Chronicle - November 29th, 2020
- Dr Apar Kishor Ganti Outlines the Effectiveness of Lurbinectedin and Benefits Over Competition - AJMC.com Managed Markets Network - November 26th, 2020
- Commonly used antibiotic shows promise for combating Zika infections - National Institutes of Health - November 26th, 2020
- A real life Superman celebrates 5 years of survival from one of the deadliest cancers - Newswise - November 26th, 2020
- Global Cell Harvesting Market to Reach US$381,4 Million by the Year 2027 - Salamanca Press - November 26th, 2020
- Tanya Siddiqi, MD, Discusses the Promise of Reduced Toxicity With Liso-Cel - AJMC.com Managed Markets Network - November 26th, 2020
- Tetracycline-based Antibiotics Show Promise for Combating Zika Infections - Global Biodefense - November 26th, 2020
- Study Suggests AYAs Treated for AML Have High Risk of Developing Long-Term Complications - Cancer Network - November 26th, 2020
- Mustang Bio Announces Positive Opinion from the European Medicines Agency on Orphan Drug Designation for Its Lentiviral Gene Therapy for the Treatment... - November 26th, 2020
- Study Finds Racial and Ethnic Disparities in Treatment of AL Amyloidosis - DocWire News - November 22nd, 2020
- New Virtual Reality Tool, Domestic Cats are SARS-CoV-2 Carriers, Combination Therapy Advances: COVID-19 Updates - Bio-IT World - November 22nd, 2020
- SEE | Smoking worsens Covid-19 infection in the airways, new study reveals - Health24 - November 22nd, 2020
- Could Cell Therapy Be The Answer To COVID-19? - CBS Boston - November 3rd, 2020
- CA Prop 14 Explained: What To Know Before You Vote Election Day - Los Angeles, CA Patch - November 3rd, 2020
- GMP Cell Banking Services Market Predicted to Accelerate the Growth by 2019-2029 - TechnoWeekly - November 3rd, 2020
- Making Progress Against Relapsed/ Refractory DLBCL Without CAR T - OncLive - November 3rd, 2020
- Orchard Therapeutics to Host Virtual R&D Investor Event on Friday, November 13, 2020 - GlobeNewswire - November 3rd, 2020
- Editorial Article: Combating cancer: The incubation technology accelerating CAR-T cell therapy development - SelectScience - October 31st, 2020
- Richters Transformation: When a Slow-Growing Cancer Turns Aggressive - SurvivorNet - October 31st, 2020
- Detroit Pistons, Make-A-Wish put a smile on the face of Commerce Township boy - The Oakland Press - October 31st, 2020
- NexImmune Establishes Research Initiative with City of Hope to Focus on Novel Immunotherapeutic Approaches to Acute Myeloid Leukemia - Yahoo Finance - October 31st, 2020
- HBS and Harvard's Department of Stem Cell and Regenerative Biology Receive $25 Million Gift from The Chris and Carrie Shumway Foundation to Support... - October 23rd, 2020
- Harnessing regeneration of retinal tissues: An option almost within reach - Ophthalmology Times - October 23rd, 2020
- Fate Therapeutics' and Celyad's CAR therapies in oncology offer potential - pharmaceutical-technology.com - October 23rd, 2020
- World Wide Stem Cell Treatment Centers Provides Exceptional Regenerative Treatment Options To Those in Need - GlobeNewswire - October 16th, 2020
- Proposition 14: Stem cell research bonds City Times - City Times - October 16th, 2020
- BrainStorm Announces Financial Results for the Third Quarter of 2020 and Provides a Corporate Update - PRNewswire - October 16th, 2020
- How a UCSF team is giving Cronutt the sea lion a second chance with neuroscience - University of California - October 16th, 2020
- Caliber Pain is Featured as a 2020 Top NYC Patient Rated Pain Management Practice by Find Local Doctors - PR Web - October 10th, 2020
- Report of the president: Appointments and promotions | Stanford News - Stanford University News - October 10th, 2020
- UTSW Scientist: 'We Need More Women Thinking Creatively in the Lab and Pushing Science Forward' - dallasinnovates.com - October 10th, 2020
- Here's what is known about Trump's COVID-19 treatment - Science Magazine - October 4th, 2020
- Election Guide: Here's What You Need to Know About Proposition 14 - NBC Bay Area - October 4th, 2020
- ASX up 2.3%, banks and energy outperform - The Sydney Morning Herald - October 4th, 2020
- Autologous Stem Cell and Non-Stem Cell Based Therapies MARKET 2020 |INDUSTRY ANALYSIS, SIZE, SHARE, TRENDS, MARKET DEMAND, GROWTH, OPPORTUNITIES AND... - September 25th, 2020
- Finding The Achilles Heel of A Killer Parasite - Newswise - September 25th, 2020
- SHE Initiative Shines Light on Gender Disparities in Oncology Workforce - Targeted Oncology - September 25th, 2020
- Actinium Pharmaceuticals Successfully Completes First Dosing Cohort in the Phase 1 Study of Actimab-A and Venetoclax Combination Therapy in... - September 23rd, 2020
- Advances in the Treatment of Mantle Cell Lymphoma are Greatly Improving the Long-Term Outlook for Patients - Curetoday.com - September 23rd, 2020
- CytoDyn's Phase 2 Study of Leronlimab for Mild-to-Moderate COVID-19 Selected for Oral Presentation at the Special isirv-AVG Virtual Conference on... - September 23rd, 2020
- Opdivo (nivolumab) Demonstrated Superior Disease-Free Survival in Patients with Resected Esophageal or Gastroesophageal Junction Cancer Compared to... - September 23rd, 2020
- Coronavirus Researchers Discover How COVID-19 May Trigger Fatal Levels of Lung Inflammation - SciTechDaily - September 21st, 2020