The INSIDER Summary: • L’Oreal paired with a bioprinting startup in France. • Together, the companies hope to print synthetic hair follicles. • The goal is to eventually implant bioprinted follicles on a balding person. Last week, cosmetics giant L’Oreal announced a partnership with France-based bioprinting startup Poietis. Together, the two hope to print synthetic hair follicles that can first conquer the lab, then your head. All you need to bioprint a hair follicle is bioink, a laser, and some time. The laser forces tiny drops of bioink made up of living cells in very specific positions on a substrate, then layers it to create a structure. Over the next few weeks, the cells mature into hair follicle cells, becoming viable outside a petri dish (the company calls its process “4D bioprinting” — this maturation time is the fourth dimension). This process isn’t as straightforward as it may seem; several organisations have tried to bioprint hair follicles and failed, according to a press video from L’Oreal. Hair follicles contain 15 different types of cells that must cyclically grow new hair, and the average human head has about 150,000 of them.
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