https://www.ambrosiaplasma.com

A startup company has now launched the first clinical trial in the United States to test the anti ageing benefits of young blood in relatively healthy people. But there's a big caveat: It's a pay-to-participate trial, a type that has raised ethical concerns before, most recently in the stem cell field.

The firm’s co-founder and trial principal investigator is a 31-year-old physician named Jesse Karmazin. His company, Ambrosia in Monterey, California, plans to charge participants $8000 for lab tests and a one-time treatment with young plasma: a single transfusion of a two litre bag.

http://uk.businessinsider.com/young-blood-transfusions-aging-disease-ambrosia-2017-1

No where on website states how young donors are selected.