2020 began with the Feeley-Liu lab at the ORS Annual Meeting in Phoenix, Arizona. The group presented several abstracts, including their paper entitled “Inducible endogenous stem cells within human rotator cuff muscle to promote muscle regeneration after rotator cuff repair” which highlighted their work on studying different populations of muscle stem cells and how they react to rotator cuff injury. This paper was later published in the American Journal of Sports Medicine. He Zhang and Mengyao Liu both presented multiple papers and posters at the meeting.
We were proud to see lab alumni Carlin Lee, MD, awarded with the Neer Award by the American Shoulder and Elbow Surgeons for best basic science paper. Carlin worked for several years in the lab, and pioneered muscle stem cell transplantation techniques to improve rotator cuff repair outcomes. Unfortunately, with the AAOS Annual Meeting cancelled due to COVID, we were unable to see his presentation at the meeting.
We were fortunate to be joined by several new lab members including UCSF medical students Gurbani Kaur, Francisco Gomez-Alvarado, and Hannah Chi. Agustin Diaz joined the lab as a research assistant and Steven Sputa joined as a senior lab technician. Michael Davies, a former UCSF medical student and current orthopedic surgery resident, began his clinician scientist training year in the lab, and promptly wrote multiple strong grants resulting in the AOSSM Young Investigator Award for his work on human muscle cells. We were sad to see AJ Agha leave, but have welcomed him back as a UCSF orthopaedic surgery resident and look forward to his continued research with the lab. Of course, Zili Wang continues to contribute from overseas, and we continue to miss his outstanding surgical skills in lab!
Despite being considerably limited by COVID, we have adopted new strategies and techniques, developed Zoom lab meeting skills, and built new collaborations within the UCSF community. We have embarked on the spine/low back pain journey with Jeff Lotz and Jeannie Bailey, working with them and a team of neuroscientists on the interaction between muscle changes and low back pain. We have been fortunate to develop other collaborations that we hope will be rewarding in 2021, with explorations into new cell delivery systems, advanced gene analysis techniques, and collaborations with scientists in hand surgery, vascular surgery, neurology, and beyond.
Several projects were successfully completed, likely due to the fact that there was often little else to do other than read and write papers! Below is a list of the papers published in 2020:
1: Zhang H, Liu M, Kim HT, Feeley BT, Liu X. Preconditioning improves muscle
regeneration after ischemia-reperfusion injury. J Orthop Res. 2020 Nov 24. doi:
10.1002/jor.24909. Epub ahead of print. PMID: 33232533.
2: Liu X, Liu M, Lee L, Davies M, Wang Z, Kim H, Feeley BT. Trichostatin A
regulates fibro/adipogenic progenitor adipogenesis epigenetically and reduces
rotator cuff muscle fatty infiltration. J Orthop Res. 2020 Sep 24. doi:
10.1002/jor.24865. Epub ahead of print. PMID: 32970360.
3: Feeley BT, Liu M, Ma CB, Agha O, Aung M, Lee C, Liu X. Human Rotator Cuff
Tears Have an Endogenous, Inducible Stem Cell Source Capable of Improving Muscle
Quality and Function After Rotator Cuff Repair. Am J Sports Med. 2020
Sep;48(11):2660-2668. doi: 10.1177/0363546520935855. Epub 2020 Jul 30. PMID:
32730704.
4: Agha O, Diaz A, Davies M, Kim HT, Liu X, Feeley BT. Rotator cuff tear
degeneration and the role of fibro-adipogenic progenitors. Ann N Y Acad Sci.
2020 Jul 29. doi: 10.1111/nyas.14437. Epub ahead of print. PMID: 32725671.
5: Agha O, Mueller-Immergluck A, Liu M, Zhang H, Theologis AA, Clark A, Kim HT,
Liu X, Feeley BT, Bailey JF. Intervertebral disc herniation effects on
multifidus muscle composition and resident stem cell populations. JOR Spine.
2020 May 6;3(2):e1091. doi: 10.1002/jsp2.1091. PMID: 32613166; PMCID:
PMC7323461.
6: Wang Z, Liu X, Liu M, Jiang K, Kajimura S, Kim H, Feeley BT.
Β3 Adrenergic receptor agonist treats rotator cuff fatty infiltration
by activating beige fat in mice. J Shoulder Elbow Surg. 2021 Feb;30(2):373-386.
doi: 10.1016/j.jse.2020.06.006. Epub 2020 Jun 27. PMID: 32599287; PMCID:
PMC7765745.
7: Wang Z, Liu X, Jiang K, Kim H, Kajimura S, Feeley BT. Intramuscular Brown Fat
Activation Decreases Muscle Atrophy and Fatty Infiltration and Improves Gait
After Delayed Rotator Cuff Repair in Mice. Am J Sports Med. 2020
Jun;48(7):1590-1600. doi: 10.1177/0363546520910421. Epub 2020 Apr 13. PMID:
32282238.
8: Lee C, Liu M, Agha O, Kim HT, Feeley BT, Liu X. Beige FAPs Transplantation
Improves Muscle Quality and Shoulder Function After Massive Rotator Cuff Tears.
J Orthop Res. 2020 May;38(5):1159-1166. doi: 10.1002/jor.24558. Epub 2019 Dec
19. PMID: 31808573; PMCID: PMC7162719.
9: Lee C, Agha O, Liu M, Davies M, Bertoy L, Kim HT, Liu X, Feeley BT. Rotator
Cuff Fibro-Adipogenic Progenitors Demonstrate Highest Concentration,
Proliferative Capacity, and Adipogenic Potential Across Muscle Groups. J Orthop
Res. 2020 May;38(5):1113-1121. doi: 10.1002/jor.24550. Epub 2019 Dec 13. PMID:
31799698.
10: Lee C, Liu M, Agha O, Kim HT, Liu X, Feeley BT. Beige fibro-adipogenic
progenitor transplantation reduces muscle degeneration and improves function in
a mouse model of delayed repair of rotator cuff tears. J Shoulder Elbow Surg.
2020 Apr;29(4):719-727. doi: 10.1016/j.jse.2019.09.021. Epub 2019 Nov 26. PMID:
31784382; PMCID: PMC7085983.
