Abstract: Objective To investigate the influence of keratinocytes on the growth of Trichophyton rubrum in vitro.Methods The hyphae suspension of T.rubrum was prepared in Dulbecco's Modified Eagle's Medium (DMEM) without bovine serum at working concentration of 0.1×10⁵/mL to 1.0×10⁵/mL,and preserved at 4℃.HaCaT cells,an immortal human keratinocyte cell line,were grown in DMEM supplemented with 10% calf serum at 37℃ in humidified air with 5% CO₂ until 80% confluency.After removel of the cell culture supematant,the hyphae suspension was added to coculture with HaCaT cells,with the suspension alone as a negative control.The hyphae suspension was harvested after 4,8,16,and 24 h of conculture,and fungal viability was determined by trypan blue staining and enumeration of the colony-forming units.Finally,the growth inhibitory rates of Trichophyton rubrum at each time point were calculated.Results With trypan blue staining,the growth inhibitory rates of Trichophyton rubrum at 4,8,16,and 24 h were 46.8±8.0%,64.0±5.5%,76.3±7.7%,and 39.5±4.9%,respectively.Enumeration of the colony-forming units revealed that the inhibitory rates were 39.7±4.9%,58.0±8.9%,68.3±7.4%,and 39.9±5.5% at 4,8,16,and 24 h,respectively.Conclusion HaCaT cells can inhibit the growth of Trichophyton rubrum in vitro.

Key words: Keratinocytes, Trichophyton rubrum, Cells, cultured