Figure. Cell proliferation of 3T3 cells after stimulated with EGF.
Epidermal growth factor (EGF) binding to EGFR, results in cellular proliferation, differentiation, and survival. To test the effect of EGF on cell proliferation, 3T3 fibroblasts cells were seeded into triplicate wells of 96-well plates at a density of 2,000 cells/well and allowed to attach, replaced with serum-free overnight, then the medium was replaced with 1% serum standard DMEM prior to the addition of various concentrations of recombinant rat EGF. After incubated for 96h, cells were observed by inverted microscope and cell proliferation was measured by Cell Counting Kit-8 (CCK-8). Briefly, 10µL of CCK-8 solution was added to each well of the plate, then the absorbance at 450nm was measured using a microplate reader after incubating the plate for 1-4 hours at 37℃. Proliferation of 3T3 cells after incubation with EGF for 96h observed by inverted microscope was shown in Figure 1. Cell viability was assessed by CCK-8 (Cell Counting Kit-8 ) assay after incubation with recombinant EGF for 96h. The result was shown in Figure 2. It was obvious that EGF significantly increased cell viability of 3T3 cells.
(A) 3T3 cells cultured in DMEM, stimulated with 1ng/mL EGF for 96h;
(B) Unstimulated 3T3 cells cultured in DMEM for 96h.

Figure. Cell proliferation of 3T3 cells after stimulated with EGF.