应用Ⅱ型胶原为载体的异种异体移植修复关节软骨缺损

背景已有用Ⅱ型胶原作为载体的软骨细胞移植的实验动物模型,Ⅱ型胶原是否引起实验性的关节炎或者发生由Ⅱ型胶原介导的细胞毒的反应尚未明确.目的检测用猪Ⅱ型胶原免疫新西兰大白兔的细胞免疫状态.设计以实验动物为研究对象,观察对比的探索性研究.单位一所市级医院创伤外科研究所.材料实验于1999-08/2000-02在广州红十字会医院创伤外科研究所完成.新西兰大白兔6只,雌雄不限,体质量2.0～3.0kg.方法用Ⅱ型胶原免疫新西兰大白兔60 d,定期抽取血浆检测抗Ⅱ型胶原抗体;第60天取兔的外周血淋巴细胞,取兔脾细胞、淋巴结分离淋巴细胞,进行体外2次Ⅱ型胶原刺激,检测由此引起的反应性的细胞增殖规律.随机分为两组,第1组加入不同浓度植物血凝素(phytohemagglutinin,PHA)作阳性对照,并测定非特异性免疫;第2组加入不同浓度Ⅱ型胶原,检测特异性免疫.主要观察指标①兔抗Ⅱ型胶原抗体含量检测.②正常兔与免疫兔脾淋巴细胞增殖试验比较.③正常兔和免疫兔淋巴结淋巴细胞增殖试验比较.④正常兔和免疫兔外周血淋巴细胞增殖试验比较.结果第21天抗体效价出现第1次高峰,再次注射抗原40 d后出现第2次高峰,维持20 d后逐渐下降,正常兔的淋巴细胞在PHA刺激下发生增殖,但对Ⅱ型胶原的第1次刺激不发生增殖,而免疫兔对PHA和Ⅱ型胶原的刺激均能发生显著的增殖,Ⅱ型胶原浓度为25 mg/L已有发生,在50mg/L出现高峰.结论异种Ⅱ型胶原在一定浓度下,可以引起免疫兔的抗Ⅱ型胶原抗体的升高,并可引起兔脾、外周血淋巴细胞增殖,在体内引起细胞免疫反应,且可引起移植免疫性关节炎.

Type Ⅱ collagen as the carrier for xenogeneic chondrocyte transplantation for joint cartilage defect repair

BACKGROUND: Type Ⅱ collagen has been used as the carrier for chondrocyte transplantation in animal models, but whether type Ⅱ collagen may cause arthritis or mediate cytotoxicity remains unknown.OBJECTIVE: To detect the cellular immune functions of the New Zealand rabbits immunized by porcine type Ⅱ collagen.DESIGN: An exploratory comparative study based on the observations.SETTING: An institute of trauma surgery of a municipal hospital.MATERIALS: The study was conducted in the Institute of Trauma Surgery,Guangzhou Red Cross Hospital from August 1999 to February 2000. Six New Zealand rabbits, whose body mass ranged from 2.0 kg to 3.0 kg, were chosen of either gender.METHODS: The rabbits were immunized by porcine type Ⅱ collagen for 60days, during which the plasma was regularly taken for detection of type Ⅱ collagen antibody. On the 60th day, the peripheral blood as well as the spleens and lymph nodes were taken to separate the lymphocytes, which were subjected to secondary stimulation with type Ⅱ collagen in vitro to observe the reactive cell proliferation. The lymphocytes were randomly divided into two groups, and the first group was treated with phytohemagglutinin(PHA) of different concentrations to serve as the positive control, in which non-specific immunity was examined; The second group was treated with type Ⅱ collagen of different concentrations for examining specific immunity.peripheral blood lymphocytes of normal and immunized rabbits.RESULTS: On the 21st day, the titer of the antibody presented the first peak, and 40 days after the re-injection of the antigen the second peak appeared, which maintained for 20 days and then gradually descended. The lymphocytes of the normal rabbits proliferated in response to PHA stimulation but not to the first stimulation with the type Ⅱ collagen. The lymphocytes of the immunized rabbits exhibited significant proliferation upon stimulations with both PHA and type Ⅱ collagen. At the concentration of 25 mg/L, type Ⅱ collagen stimulation was sufficient to induce lymphocyte proliferation, the peak of which occurred when the collagen concentration reached 50 mg/L.CONCLUSION: Xenogenic type Ⅱ collagen at an adequate concentration may induce the increase of the type Ⅱ collagen antibody in immunized rabbits and proliferation of lymphocytes of the spleens and peripheral blood to cause cellular immune reaction and even immunological arthritis in relation to the transplantation.