"Many people have dogs. We have stem cells," says Cedars-Sinai Hospital lab manager Loren Ornelas-Menendez about why they will be working on Thanksgiving, hand-feeding a special formula to their charges and making sure they stay at just the right temperature. Like they do every day, 365 days a year.

This is not just any lab, it houses stem cells derived from hundreds of healthy donors and patients, and a catalog of human ills, including diabetes, breast cancer, Alzheimer's disease, Parkinson's disease and Crohn's disease.

The lab's main collection consists of induced pluripotent stem cells, or iPSCs, which mimic the all-powerful stem cells we all had as embryos. These cells, genetically engineered from adult cells, can make any type of cell in the body-each one matching the DNA of the donor. Other types of stem cells in the lab make only one or two kinds of cells, such as brain or intestinal cells.



Handy and versatile as they are, stem cells are high-maintenance. A few types, such as those that make connective tissue cells for wound healing, can be fed as infrequently as every few days. But iPSCs require a daily meal to stay alive, plus daily culling to weed out cells that have started to turn into cells of the gut, brain, breast or other unwanted tissues.

So each day, lab staff suit up and remove trays of stem cells from incubators that are set at a cozy 98.6 degrees. Using microscopes, they carefully remove the "bad" cells to ensure the purity of the iPSCs they will provide to researchers at Cedars-Sinai and around the world.

While the cells get sorted, a special feeding formula is defrosting in a dozen bottles spread around a lab bench. The formula incudes sodium, glucose, vitamins and proteins. Using pipettes, employees squeeze the liquid into food wells inside little compartments that contain the iPSCs. Afterward, they return the cells to their incubators.

The lab's 10 employees are on a rotating schedule that ensures the lab is staffed on weekends and holidays, not just weekdays. On Thanksgiving Day this year, the lucky draw went to biomedical technician Louis Pinedo who will several hours at work filling nearly 600 feeding wells before stuffing his own belly. On both Christmas and New Year's Day, two employees are expected to staff the lab.