INS and keratoconus: Here we tested the growth and proliferation (Fig. 5) of 4 individual DN and 4 KC samples in serum free media Low-glucose (LGSF), high-glucose (HGSF) or DMEM: F12 (F12) serum free media containing insulin, transferrin and selenium (ITS) and /or TGF β1, by measuring viable cell content over 7 days.