When Mark Katakowski turned 40, three years ago, he was hit by the sudden jolt of a midlife crisis. But instead of splurging on a Porsche, he utilized his 15 years of experience in bone mesenchymal stem cell (MSC) research to found a biotech startup with the intention to help himself and other people stay young longer.

In 2015, Katakowski and his friend Steven Clausnitzer, a former American Express executive, co-founded Forever Labs, an Ann Arbor, Mich.-based company that provides a science fiction-like service: freeze stem cells of young adults in hopes of injecting them back into those people when they get older.

For example, if you are 30 and fear that your knees will wear out faster than the rest of your body, you can store away a small cup worth of bone marrow, which contains your bone mesenchymal stem cells. By the time you turn 60, you can inject those stem cells back into your knees, and, voilà, your 60-year-old self now has a pair of 30-year-old knees!

This approach can be used to combat more serious age-related diseases, too, such as strokes and dementia.

Katakowski began exploring the idea of stem cell banking around 2011 after noticing an explosion of clinical research on MSC within academia.

“From the clinical trials that were going on, we realized that there’s a lot of therapeutic potential in this,” Katakowski said in a recent interview with Observer. “The decline of stem cells in aging bodies underpins a lot of age-related diseases. So we thought: instead of treating those diseases, what if we replace the loss of stem cells?”

“You stem cells are very valuable. And when you have age-related diseases, they are more valuable. But they lose that value [as you age] until you can stop it,” he added. “Forever Labs is like a health insurance in which you can bank your young biology.”

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Forever Labs’ bone marrow extraction procedure is similar to that of a standard bone marrow donation but only requires about 10 percent of the typical donation amount.

For a one-time procedure fee of $1,500 to $2,500—plus an annual storage fee of $250—you can freeze your stem cells for as long as you want. However, injecting them back in is something that has yet to be commercialized and will inevitably require FDA approval.

Still, the prospect Forever Labs affords has attracted a loyal fanbase.

“I witnessed my grandmother, who was extremely healthy her entire life, suffer from Alzheimer’s. If there’s anyway this could help cure that disease or keep it from happening, I think it’s 100 percent worth investing in now,” Kerri Schlottman, a 42-year-old art executive who recently banked her stem cells with Forever Labs, told Observer.

“Watching the rapid improvements in healthcare and how tech is changing that, I think it would be crazy not to do this,” Schlottman said. “I’m already 42, and I’m not getting any younger. I wish this had been an opportunity when I was 20.”

Katakowski said clinical trials for treating neurological diseases using stem cell replacement are still in early stages. But, in a few more years, it’s not too crazy to imagine that this technology may one day help humans live forever.