[Clinical study of cell sheets containing allogeneic keratinocytes and fibroblasts for the treatment of partial-thickness burn wounds].

Objective: To evaluate the efficacy and safety of cell sheets containing allogeneic keratinocytes and fibroblasts in the treatment of partial-thickness burn wounds. Methods: The cell sheets containing allogeneic keratinocytes and fibroblasts were constructed using polyurethane biofilm as carrier. Then gross observation and histological observation were conducted. From April 2016 to December 2017, Changhai Hospital of Naval Medical University recruited patients with acute partial-thickness burn wounds that met the inclusion criteria for this prospective and positively self-controlled clinical trial. Recruitment of 40 acute partial-thickness burn wounds were planned with each selected single wound being not smaller than 10 cm×10 cm and not more than 5% total body surface area (TBSA). Each wound was equally divided into two areas, which were recruited into cell sheet group and conventional treatment group according to the random number table. The wounds in cell sheet group were covered by cell sheet and then sterile gauze as secondary dressings. Depending on the wound healing and exudation, the sterile gauze was replaced every 1 to 3 day (s) after the treatment was started, and the cell sheet was replaced every 7 days (namely dressing changing). The wounds in conventional treatment group were covered by sulfadiazine silver cream gauze and then dressed with sterile gauze, with the dressings changed every 2 to 3 days depending on wound exudation. On treatment day 5, 7, 10, and 14, the wound healing rates in the two groups were calculated. The complete wound healing time, the total number of dressing changes, and the status of wound infection during treatment were recorded. The Visual Analogue Scale was used to score the pain at the first dressing change. Scar formation of patients was followed up for 6 to 12 months after injury. Safety indicators including vital signs, laboratory examination indexes, and adverse reactions during treatment were observed. Data were statistically analysed with Wilcoxon rank sum test and Bonferroni correction. Results: (1) Each prepared cell sheet had a diameter of about 8 cm and was about 49 cm(2) in size, containing 2 or 3 layers of keratinocytes and fibroblasts. (2) A total of 43 patients were enrolled, of whom 3 patients dropped out of the study. Of the 40 patients who completed the treatment, there were 22 males and 18 females who were aged 1 to 57 year (s), with total burn area of 2% to 26% TBSA. (3) On treatment day 5, 7, 10, and 14, the wound healing rates in cell sheet group were significantly higher than those in conventional treatment group (Z=4.205, 4.258, 3.495, 2.521, P<0.05 or P<0.01). The complete wound healing time in cell sheet group was 7 (6, 8) days, which was significantly shorter than 11 (7, 14) days in conventional treatment group (Z=4.219, P<0.01). The total number of wound dressing changes in cell sheet group was 1 (1, 2) times, which was significantly less than 6 (4, 7) times in conventional treatment group (Z=5.464, P<0.01). (4) The wounds in cell sheet group in 31 patients healed before the first dressing change. The pain score of wounds in the first dressing change in cell sheet group of 9 patients was 1 (0, 1) point, while the pain score of wounds in the first dressing change in conventional treatment group of 40 patients was 2 (1, 3) points. There was no obvious infection in the wounds in both groups of 40 patients before the wound healing. Nine patients completed the follow-up after the trial. In 6 patients, no scar formation was observed in cell sheet group or conventional treatment group. The color of wounds in cell sheet group was consistent with normal skin, and there was only a small amount of pigment deposition in the wounds of conventional treatment group. Three patients developed pigment deposition only in the wounds of cell sheet group but obvious scars in conventional treatment group. (5) The abnormal fluctuations of vital signs including body temperature, blood pressure, heart rate, respiratory rate, and laboratory examination indexes of all patients during treatment were alleviated through the process of burn wound healing. No obvious adverse reactions or abnormalities related to the treatment were observed. Conclusions: The cell sheet containing allogeneic keratinocytes and fibroblasts can reduce the number of dressing changes, accelerate wound epithelialization, shorten wound healing time, reduce pain during dressing change in the treatment of partial-thickness burn wounds, and it may reduce scar hyperplasia after wound healing because of accelerating wound epithelization. Its clinical application is simple, safe, and effective.目的： 临床评价含异体角质形成细胞(KC)和成纤维细胞(Fb)的细胞膜片治疗Ⅱ度烧伤创面的效果与安全性。 方法： 以聚氨酯生物膜为载体构建含人异体KC和Fb的细胞膜片，行大体和组织学观察。2016年4月—2017年12月，海军军医大学附属长海医院对符合入选标准的急性Ⅱ度烧伤创面的患者进行前瞻性、阳性自身对照的临床试验。拟入组40个急性Ⅱ度烧伤创面，选择的单个创面≥10 cm×10 cm且≤5%体表总面积(TBSA)，将创面均分为2个区，采用随机数字表法分别纳入细胞膜片组和常规治疗组。细胞膜片组创面内层覆盖细胞膜片、外覆无菌植皮纱布，视创面愈合及渗出情况于治疗开始后每1～3天更换外层纱布，每7天更换1次细胞膜片(即该组换药)。常规治疗组创面内层覆盖混合磺胺嘧啶银霜的纱布、外覆无菌植皮纱布，视创面渗出情况每2～3天更换内外层纱布。分别于治疗5、7、10、14 d，计算2组创面愈合率；记录创面完全愈合时间、换药总次数、治疗期间创面感染情况；首次换药时采用视觉模拟评分法进行疼痛评分；伤后6～12个月，随访创面瘢痕形成情况。观察安全性指标包括治疗期间生命体征和实验室检查指标及不良反应。对数据行Wilcoxon秩和检验及Bonferroni校正。 结果： (1)制备的细胞膜片直径约8 cm，每片面积约49 cm(2)，含2层或3层KC和Fb。(2)共入选43例患者，其中3例脱落。完成治疗的患者中，男22例、女18例，年龄1～57岁，烧伤总面积为2%～26%TBSA。(3)治疗5、7、10、14 d，细胞膜片组创面愈合率均明显高于常规治疗组(Z＝4.205、4.258、3.495、2.521，P<0.05或P<0.01)。细胞膜片组创面完全愈合时间为7(6，8)d，明显短于常规治疗组的11(7，14)d(Z＝4.219，P<0.01)。细胞膜片组创面换药总次数为1(1，2)次，明显少于常规治疗组的6(4，7)次(Z＝5.464，P<0.01)。(4)31例患者细胞膜片组创面在首次换药前即已愈合，9例患者细胞膜片组创面首次换药疼痛评分为1(0，1)分；40例患者常规治疗组创面首次换药疼痛评分为2(1，3)分。40例患者2组创面完全愈合前均未见有明显感染发生。试验结束后，9例患者完成随访，其中6例患者细胞膜片组创面与常规治疗组创面均未见瘢痕形成，细胞膜片组创面颜色与正常肤色一致，仅见常规治疗组创面少量色素沉积；3例患者细胞膜片组创面仅有色素沉积，而常规治疗组创面瘢痕形成明显。(5)所有患者治疗期间体温、血压、心率、呼吸频率等各项生命体征指标及实验室检查指标异常波动主要随烧伤病程演进及创面愈合自行缓解，未见明显与治疗相关的不良反应与异常表现。 结论： 含异体KC和Fb的细胞膜片可减少Ⅱ度烧伤创面换药次数、加速创面上皮化、缩短愈合时间、减轻换药疼痛；由于其加速创面上皮化进程，可能有利于减轻创面愈合后的瘢痕增生；临床应用简便、安全、有效。.