 In contrast, ADF/cofilin has some properties that antagonize profilin action.Profilin was first described by Lars Carlsson in the lab of Uno Lindberg and co-workers in the early 1970s as the first actin monomer binding protein.It followed the realization that not only muscle, but also non-muscle cells, contained high concentrations of actin, albeit in part in an unpolymerized form.