评估采用GGTA1/β4GalNT2双基因敲除近交系五指山小型猪皮进行猪－猴移植的效果。

供体猪断层皮肤分别取自双基因敲除近交系五指山小型猪、野生型五指山近交系小型猪，受体为恒河猴，按移植皮片不同分为实验组、对照组，每组4只。于每只恒河猴背部制成4个全层皮肤切除创面，分别移植双敲基因猪皮、野生型猪皮。术后不同时间点观察移植皮片的颜色、质地等，评估皮片活力，并取标本进行病理检查；不同时间点留取血清检测IL-2、IL-4、IL-12、IFN-γ含量与IFN-γ/IL-4。

双敲基因猪皮片的平均存活时间为(13.9±3.1)d，长于野生型猪皮的(11.0±2.0)d(t＝－3.0901，P＝0.0043)。术后早期两组皮片均成活良好；术后第7天，双敲基因猪皮外观仍红润，部分野生型猪皮可见皮下大水疱或小水疱或紫绀等排异表现；术后第10天，双敲基因猪皮片的质地较野生型猪皮柔软，野生型猪皮于之前发现的紫绀表现仍存在；术后第12天，部分双敲基因猪皮片质地仍完整、柔软，野生型猪皮无完整红润的皮片存在；术后第14天，双敲基因猪皮与野生型猪皮分别有9块、14块皮片完全脱落，双敲基因猪皮脱落率低于野生猪皮(Pearson chi²＝3.8647，P＝0.049)，仍存在于创面的7个双敲基因猪皮中的2块保持温暖、柔软，至术后第21天干燥、失活。病理观察显示两种皮肤移植后早期无明显差别；术后第7天，双敲基因猪皮和野生型猪皮表皮层细胞数量减少，真皮胶原组织水肿，野生型猪皮表皮层内出现小空泡；部分双敲基因猪皮和野生型猪皮与基底床紧密相连，形成嫁接；术后第10天，两种猪皮表皮细胞数量较前继续减少，表皮层均可见空泡，其中双敲基因猪皮表皮层出现的空泡与野生型猪皮在术后第7天的表现类似，而野生型猪皮表皮层的空泡较前明显增多增大，两种皮肤与基底床仍紧密连接；术后第14天，部分双敲基因猪皮整体结构仍基本保持完整，但表皮层空泡明显扩大，使得表皮层与真皮层大部分分离，真皮与基底仍形成连接；野生型猪皮脱落后基底床暴露，基底肉芽组织增生，大量炎细胞浸润。两组血清IL-2、IL-4、IL-12、IFN-γ水平与IFN-γ/IL-4比值比较未见规律性改变。

GGTA1/β4GalNT2双基因敲除近交系五指山小型猪皮免疫排异性减轻，存活时间延长，有应用于临床治疗烧伤创面的前景。

To evaluate the effect of pig-monkey skin transplantation using GGTA1/β4GalNT2 double gene knockout inbred Wuzhishan miniature pig.

Donor pig split skins were taken from double gene knockout inbred Wuzhishan miniature pigs and wild type Wuzhishan inbred miniature pigs. The recipients were rhesus monkeys. According to different skin graft donors, they were divided into experimental group and control group, 4 in each group. Four full-thickness skin excision wounds were made on the back of each rhesus monkey, and double-knocked-gene pig skin and wild-type pig skin were transplanted respectively. The color and texture of the grafted skin were observed at different time points after the operation, the vitality of the skin was evaluated, and specimens were taken for pathological examination. Serum were collected at different time points to detect the contents of IL-2, IL-4, IL-12, IFN-γ and IFN-γ/IL-4.

The average survival time of double-knock-out pigskin was (13.9±3.1)days, which was longer than that of wild-type pigskin (11.0±2.0)d (t=-3.0901, P=0.0043). In the early postoperative period, both groups of skins survived well. On the 7th day after the operation, the double-knockout pig skin grafts were still ruddy, and some wild-type pig skins showed rejection manifestations such as big or small blisters, or cyanosis. On the 10th day after the operation, the texture of the double gene knockout skin grafts were softer than that of the wild type pig skin. The cyanosis of the wild type pig skin still exists. On the 12th day after the operation, some double gene knockout skin grafts were still intact and soft, however, intact and ruddy skin grafts could not be found in wild-type pigskin grafts. On the 14th day after the operation, 9 and 14 grafts of double-knock-out pigskin and wild-type pigskin were completely peeled off, respectively. The shedding rate of double-knock-out pigskin was lower than that of wild pig skin group (Pearson chi²=3.8647, P=0.049). Among the 7 double-knockout pig grafts still presented in the wound, two grafts were still ruddy, warm, and soft, and the two grafts turned to crust and lost viablity on the 21st day after surgery. Pathological observation showed that there was no significant difference in the early stage after the two types of skin transplantation. On the 7th day after the operation, the number of epidermal cells decreased and dermal collagen tissue were edema in the epidermis of two types of pig skin. Small vacuoles appeared in the epidermis of wild-type pig skin. A part of double-knocked pig skin and wild-type pig skin were closely connected to the wound bed to form an " engraft". On the 10th day after operation, the number of epidermal cells in the two types of pig skin continued to decrease compared with before, and vacuoles were seen in the epidermis. Among them, the vacuoles in the epidermis of the double-knock gene pigskin were similar to iof the wild-type pig skin increased significantly compared with the previous ones. Both grafts and the wound bed were still tightly connected. On the 14th day after the operation, the overall structure of some double-knocked pig skins remained basically intact, but the vacuoles in the epidermis were significantly enlarged, so that most of the epidermis and dermis were separated, and the dermis was still connected to the wound bed. After the wild-type pig skin fell off, the wound bed was exposed, the granulation tissue proliferated and a large number of inflammatory cells infiltrated. There was no regular change in the levels of serum IL-2, IL-4, IL-12, IFN-γ and IFN-γ/IL-4 between the two groups.

The immune rejection of GGTA1/β4GalNT2 double gene knockout inbred line Wuzhishan miniature pig skin is reduced and its survival time is prolonged. It has the prospect of clinical application to treat burn wounds.