Evaluation of the Role of Granzyme B in Exuberant Scar Pathogenesis: An Immunohistochemical Study.

Objective: To evaluate the possible role of Granzyme B (GzmB) in abnormal wound healing through its immunohistochemical expression in keloid and hypertrophic scars and to study the relationship of its expression with the clinicopathologic parameters of studied cases.

Study design: Using immunohistochemical techniques, GzmB was analyzed in skin biopsies of 44 patients (30 cases with abnormal scars [21 with keloid and 9 with hypertrophic scars] and 14 age- and gender-matched cases with surgical scars as a control group).

Results: GzmB was expressed in keratinocytes in 28.6%, 66.7%, and 23.8% of surgical scars, hypertrophic scars, and keloids, respectively. Dermal expression in inflammatory cells was detected in 64.3%, 44.4%, and 28.6% of surgical scars, hypertrophic scars, and keloids, respectively. No significant difference was noted in GzmB expression intensity or percent in comparison between studied groups.

Conclusion: GzmB plays no role in the pathogenesis of keloids and hypertrophic scars. Further large-scaled studies are needed to expand or refute the current observation.