Effects of autologous keratinocyte cell spray with and without chitosan on third degree burn healing: an animal experiment.

UNLABELLED:Treatment of extensive third degree burns, especially in the case of limited skin donor sites for obtaining autologous split-thickness skin grafts (STSG), has led to in vitro expansion of keratinocytes. Cultured epidermal autograft (CEA) sheets have been used for burn treatment for several years. However, time consuming processes of isolation and cultivation of keratinocytes, as well as difficult procedures of detachment of CEA from cultured flasks, led scientists to develop the technique of spraying cultured single keratinocytes (CSK) instead of using CEA. Chitosan is a well-known wound dressing biomaterial that has both biological and medical applications. In this study, the application method of CSK was used to determine whether there would be any significant difference between the treatment of burns with CSK alone in comparison to burns treated with CSK and covered with chitosan gel at a neutral pH. MATERIALS AND METHODS:Thirty male Wistar rats were selected and their keratinocytes were isolated and cultured from small skin biopsy. Rats were divided randomly into 3 equal groups and 3 full-thickness round burn wounds were created on their backs. Rats were treated with either normal saline (control group), CSK (test group A), or CSK + neutral chitosan (CSK+ NCH) (test group B). The wounds were photographed on days 0, 3, 5, 7, 10, and 14, and the percentage of wound contraction was calculated with an image analyzer. Biopsy samples were taken for histological studies. RESULTS:The results showed faster wound contraction for test groups A and B during the 14-day period than the control group (P < 0.05). Also, more contraction was found in test groups A and B in 7 days (P < 0.05). Histological observations showed significant difference in inflammation and fibrotic tissue formation between groups, but other parameters did not show any remarkable difference. CONCLUSION:Based on the findings of this study, the authors concluded that chitosan can prevent cells from dripping out of the wound, speed up wound contraction, and extend fibrotic tissue formation. Chitosan did not, however, have any effect on fastening the reepithelialization and granulation tissue formation during the first 14 days.