Additional file 1 : Figure S1. M14 cells treated with different RTIs. Cells have been exposed for 72 h to perform clonogenic assays in the presence of SPV122 or Efavirenz (as NNRTIs, upper plates) and Zidovudine or Stavudine (as NRTIs, lower plates). Inhibitors have been used starting from 100 μM and then diluted 1:2 for ten times.