Mouse strain variation in SMA+ myofibroblast development after corneal injury

•Mice that have irregular phototherapeutic keratectomy develop stromal haze by one month after surgery.•Myofibroblast cells that develop in the cornea are primarily responsible for haze.•The myofibroblast response to injury varies with different mouse strains.

The purpose of present study was to investigate differences in myofibroblast development after haze-generating injury in different commonly used strains of mice. The inbred mouse strains used in this study were Balb/c, C57BL/6, C3H/HeJ and DBA/1J. All mice had uniform irregular phototherapeutic keratectomy with an excimer laser according to a previously published method to generate stromal haze. DBA/1J mice generated significantly greater density of alpha smooth muscle actin (SMA)-positive myofibroblasts in the anterior stroma compared to Balb/c (p < 0.05), C57BL/6 (p < 0.05) and C3H/HeJ (p < 0.01) mice. The C3H/HeJ strain had significantly lower density of SMA-positive myofibroblasts compared to other three mouse strains. These results indicate that mouse strain must be considered in designing experiments and interpreting the results of experiments in which corneal haze and myofibroblast generation is studied in mice. Further investigation of genetics underlying mouse strain variation could provide insight into the corneal wound healing and haze generation processes.