Current Gregg Lab Members:

Dr. Brigid Gregg, M.D.
I completed my undergraduate degree in Physiology, as a California Board of Regents Scholar, at the University of California San Diego. Subsequently, I earned my M.D. at Case-Western Reserve University College of Medicine in Cleveland, Ohio. Following CWRU, I entered the residency program in pediatrics at the University of Chicago Comer Children’s Hospital, where I also completed a fellowship in pediatric endocrinology. During my fellowship I performed postdoctoral research at the Kovler Diabetes Center under the mentorship of Dr. Christopher Rhodes. Upon completion of my training, I was recruited to the University of Michigan Medical School where I worked closely with Dr. Ernesto Bernal-Mizrachi at the Brehm Center for Research. I also provide clinical services at Mott Children’s Hospital. My current research is focused on understanding how  alterations in early life nutrients can program offspring body composition and glucose balance. The Gregg lab members and I anticipate that this line of research will be helpful in identifying children at-risk for developing metabolic disease. We also are working to develop interventions to decrease lifelong metabolic risk. 


Dr. Lindsay Ellsworth, M.D.

Lindsay is a Neonatal-Perinatal Medicine faculty member at the University of Michigan. She did her fellowship training in Dr. Gregg’s lab. She is evaluating the influence of maternal metabolic disease on breast milk macronutrients and bioactive factors, infant microbiome, infant salivary hormone levels, and maternal bisphenol A levels.

Education and Training: B.S. (Chemistry) - Hope College, 2008; M.D. - Loyola University Chicago Stritch School of Medicine, 2012; Pediatrics Residency - University of Michigan, 2015; University of Michigan Neonatal-Perinatal Medicine Fellowship, Present - 2018



Haijing Sun, M.S., Ph.D.
Haijing is the current lab manager of the Gregg Lab.  She studied at Northeast Normal University in China from 1994-2004 where she obtained her B.S., M.S., and Ph.D. in biology.  Afterward, she was a postdoc at Beijing Normal University from 2004-2006.  Following this, she was an assistant professor at Fudan University in China from 2006-2008.  She was a visiting scholar and postdoc in Minnesota, Illinois, and Michigan between 2008-2017.  She returned to China from 2017-2019 and was a lab technician at Shenzhen GSH Bio-tech Co.  Haijing joined our lab on August 12th, 2019.  

She manages the general ongoings of the lab and plans out experiments.   While enjoying cell culture biology, Haijing has a passion for adopting dogs in need.  She currently has two dogs:  Rice and Mistake.  Haijing also enjoys traveling, growing cucumbers in her backyard, and snacking on apples in between experiments.

Zach Carlson, B.S.
Zach is an intermediate lab technician.  He completed his B.S. in Biochemistry at the University of Michigan in Dec 2018.  In the summer of 2017, Zach was an intern in our lab through the Momentum Center, a research group on campus focused on diabetes, obesity, and inflammation.  

He wrote his Honor's Thesis through the Gregg Lab during his senior year.  Its focus was to determine the mechanisms by which Metformin - a commonly used drug for diabetics - exposure during lactation alters body composition in pups and to determine the impact of postnatal exposure of metformin on the offspring microbiome.  He received Highest Honors.  He is working alongside the University of Michigan's Microbiome Core and the Mothur Fluxing Core to analyze microbiome data.   In addition to analyzing the microbiome of mice on metformin, he has analyzed microbiome data on mice exposed to high-fat diet alongside metformin.  He also analyzes microbiome data of human samples from our IMAGE study.  He assists in lab bench work, animal husbandry, assays, staining, sectioning, administrative organization, and manages the lab website.  He will begin a Master's in Data Science starting this September 2020.

Nyahon Both, B.S.
Nyahon is a 1st-year master's student studying Nutritional Sciences at the University of Michigan School of Public Health. She received her B.S. in Dietetics from Iowa State University in the Spring of 2019.  She'll be working on projects analyzing human breast milk samples for various macronutrients such as glucose, carbohydrates, fat, and protein.  After graduating she hopes to become an international/global nutritionist that specializes in lactation.  In addition to this, Nyahon hopes to become a registered dietitian.  She has a passion for maternal and child health.  She enjoys baking, exploring nature, and finding places to watch the sunset.

Cecilia Rivet

Cecilia is a junior in the LSA Honors College.  Freshman year she worked with us through UROP, the Undergraduate Research Opportunity Project.  Her end-of-year poster at the annual UROP symposium won her a blue ribbon.  

She worked with us again during her sophomore year through UROP scholars.  During her second year in our lab, she was awarded an exhibition case at the University of Michigan Museum of Natural History where she designed a display case to showcase her work here. She is hoping to pursue a degree in pharmaceutical science.  

Holly Reynolds

Holly is a senior in the LSA Honors College majoring in Biomolecular Science and Native American Studies.  She speaks Italian, Japanese, Gaelic, Spanish, some German, and Swedish (she could keep going...).  She is the official "lab monkey" of the Gregg Lab and hopes to learn anything and everything with her time here.  Next year she plans to take on more lab responsibilities and write an Honor's thesis.  She is here "because I THIRST for knowledge".  

After graduating, she plans on going to medical school, specifically for trauma/ER.  She hopes to be the first female doctor to speak 20 languages fluently and kind of wants to challenge the president to hand-to-hand combat for his title.  (Note:  this is by no means a declaration of political alignment by either Holly or the Gregg Lab.) Her hobbies include opera singing, Star Trek binging, dog training, and kickboxing. 

She once claimed to finish a Monday New York Times crossword in less than four minutes.  (The jury is still out on that one.)

Stella Wu

Stella is a sophomore at the University of Michigan majoring in Cellular and Developmental Biology.  Currently, she is learning our workflow for microbiome data processing -  everything from mothur to R - and is hoping to write her thesis in our lab upon graduating.  Stella hopes to continue research work after graduating by going to grad school.  Afterward, she is planning on becoming a teaching professor that also does research.  She enjoys weightlifting, listening to podcasts, and sudoku.