Breaston, 29, had been dealing with knee inflammation earlier this offseason, but his agent, Eric Metz, told ESPN in March that MRIs performed on Breaston's knee revealed nothing alarming and he is medically cleared to continue his NFL career.
At the time he had been considering whether to have the Regenokine knee procedure in Germany, but decided against it.
During the procedure, a small cup of blood is removed from the patient, and then it is incubated at a slightly elevated temperature and spun in a centrifuge to make a serum that's injected to combat inflammation.
Breaston had been released by the Kansas City Chiefs in February.
He had been lured to Kansas City in 2011 by former coach Todd Haley and general manager Scott Pioli, and signed a $22.5 million, five-year deal. But he fell out of favor last season under coach Romeo Crennel, catching seven passes for 74 yards in 10 games.
Information from The Associated Press was used in this report.