人前磨牙牙髓牙本质复合体层粘连蛋白受体的免疫组织化学研究

目的研究层粘连蛋白受体在牙髓牙本质复合体内的表达,探讨其分布与功能的关系.方法收集新鲜健康人前磨牙60个,固定,脱钙,石蜡包埋,层粘连蛋白受体SABC免疫组织化学染色.结果层粘连蛋白受体免疫反应物(LNR-IR)普遍存在于牙髓牙本质复合体的神经纤维膜、血管内皮细胞、成牙本质细胞及成纤维细胞上,以牙髓的神经纤维膜、血管内皮细胞最为丰富.结论层粘连蛋白受体一般见于牙髓牙本质复合体的各种细胞膜上,它与层粘连蛋白一起在支持、固定牙髓牙本质复合体各结构的正常位置、形态和功能的发挥上可能起了重要作用.     

应用人自体血清培养人口腔黏膜上皮的实验研究

目的 研究人自体血清培养人口腔黏膜移植生长的生物学特性，为组织工程化尿道提供新材料。方法 将人自体血清培养黏膜移植于裸鼠体内，分别于移植后2、3、4、6周观察培养黏膜生长与转归，应用anti—HLA免疫荧光鉴定成活黏膜组织属性，应用抗人Ⅳ型胶原及抗人层黏蛋白为基底膜形成指标。结果 裸鼠体内移植培养黏膜成活生长分化良好，anti—HLA免疫荧光证实为移植的培养人黏膜组织；免疫组化发现移植后3周开始形成基底膜，4周形成完整的基底膜。结论 自体血清培养的人口腔黏膜可形成功能完整的上皮组织。     

小鼠子宫角注射层粘连蛋白及其抗血清对胚泡着床的影响

目的：研究层粘连蛋白及其特异性抗血清对胚泡着床的影响。方法：在小鼠子宫角内注射层粘连蛋白及其特异性抗血清，并对胚胎着床率与子宫内膜变化进行组织学观察。结果：提示外源性层粘连蛋白在小鼠体内有促进胚泡粘附、植入子宫内膜的趋势，但作用不明显；而层粘连蛋白抗血清则有显著抑制小鼠胚泡着床的效应。结论：小鼠体内的层粘连蛋白对胚胎粘附、着床起重要作用。     

胃癌患者血清中层粘连蛋白和Ⅳ型胶原的表达及临床意义

目的：探讨胃癌患者血清中层粘连蛋白（LN）和Ⅳ型胶原（Ⅳ－C）含量的临床意义。方法：应用放射免疫技术测定28例胃癌患者和30例健康者（对照组）血清LN及Ⅳ－C含量。结果：胃癌患者血清中LN和Ⅳ－C含量明显高于对照组（P＜0．05）；淋巴结转移组血清LN和Ⅳ－C含量明显高于无淋巴结转移组（P＜0．05）；胃癌根治术后患者血清中LN和Ⅳ-C含量与术前相比明显降低（P＜0．05）。结论：血清中LN和Ⅳ－C含量变化与胃癌细胞的浸润，转移等生物学行为密切相关，动态观察对判断胃癌病情，预后及手术根治效果具有一定的参考价值。     

转移性癌细胞对表皮生长因子和层粘连蛋白的反应及其三磷酸肌醇含量的测定

为探讨不同转移性癌细胞（ＭＦＣ和ＣＮＥ－２Ｚ）不同克隆细胞株的三磷酸肌醇（ＩＰ３）含量、侵袭能力以及这些细胞对表皮生长因子（ＥＧＦ）和层粘连蛋白（ＬＮ）的反应性。方法利用放射性受体竞争结合法和人工基底膜（ｍａｔｒｉｇｅｌ）侵袭试验法进行了测定。结果显示了低转移性癌细胞比高转移性者的ＩＰ３含量高，对ＥＧＦ的反应性更大，但ＭＦＣ高、低转移性克隆细胞对ＬＮ的反应性差别无显著意义。而ＣＮＥ－２Ｚ高转移细胞比低转移者对ＬＮ的反应性更大。结论说明高、低转移性癌细胞在跨膜信息传递方面存在差别，深入研究其具体机制将有重要意义。     

Detection by ELISA of laminin released by endothelial cells from a collagen coated layer of Matrigel

Summary We have developed an in vitro model system quantitating the degradation of extracellular matrix by endothelial cells. Collagen is layered over a reconstituted basement membrane matrix (Matrigel) and the release of laminin contained in the Matrigel into the media by endothelial cells is quantitated by ELISA. The cell-specific release of laminin is consistent and reproducible. Incubating an equivalent number of dead endothelial cells in the same manner results in no release of laminin relative to media controls. The cell-specific laminin release is abolished by removing the exogenous growth factor component of the media and plating the cells in media plus 10% serum. Cells plated onto wells coated with collagen alone do not release laminin into the media, indicating that no de novo synthesis and release of laminin occurs during the time frame of the experiment, and that some factor or combination of factors present in the media supplement is essential for the endothelial cells to release laminin degrading enzymes.     

血清及支气管肺泡灌洗液中HA,LN的检测对肺癌的诊断意义

作者应用放射免疫方法，检测了５２例肺癌病人血清及支气管肺泡灌洗液中透明质酸和层粘蛋白的水平，以１１例肺炎病人作对照。结果：肺癌组血清透明质酸和层粘蛋白水平明显高于肺炎组（Ｐ＜０．０５）；肺癌组支气管肺泡灌洗液中透明质酸明显高于肺炎组（Ｐ＜０．０５），而层粘蛋白则与肺炎组无差别。结果提示，血清透明质酸与层粘蛋白及支气管肺泡灌洗液透明质酸与层粘蛋白和支气管肺泡灌洗液透明质酸的高水平是对肺癌诊断有价值的指标。     

Epidermal Growth Factor Prolongs Survival Time of Tumor-bearing Mice

We observed that human epidermal growth factor (hEGF) alone prolonged the survival time of mice bearing various murine syngeneic tumors as well as athymic nude mice bearing human xenografts. No changes in the subcutaneous solid tumor mass volume were observed. Prolongation of survival time by hEGF was observed in mice bearing murine epidermoid carcinoma (BSC) and human gastric carcinoma (KATO III), but not in murine epidermoid carcinoma (KLN205) or human epidermoid carcinoma (A431). Human tumor cells such as A431, KATO III, and murine tumor cells, KLN205, BSC had roughly 2 × 10⁶, 3 × 10⁴, 1.3 × 10³ and 1 × 10³ EGF receptors/cell, respectively. Although KLN205 and BSC tumor cells maintained nearly the same number of EGF receptors, the effects of hEGF were very different. Although A431 tumor cells had nearly 100 times more receptors than KATO III cells, the prolongation of survival time of mice bearing A431 by hEGF was no better than that of mice bearing KATO III. Accordingly, it appears that this prolongation of survival time by hEGF is independent of the number of EGF receptors on tumor cells. In addition, hEGF was shown to inhibit experimental pulmonary metastasis of murine BSC tumor, but was ineffective with murine KLN205 tumor. These results suggest that prolongation of survival time by hEGF may result from the inhibition of tumor cell metastasis and EGF may play a role in preventing the metastasis of certain malignant neoplasms unrelated to its effects through the EGF receptor on tumor cells.     

Cleavage of laminin by thrombin and plasmin: Alpha thrombin selectively cleaves the beta chain of laminin

Highly purified -thrombin, plasmin and urokinase were incubated with laminin, type IV collagen and type V collagen. At 25°C (1:100 enzyme to substrate ratio on a weight/weight basis) -thrombin selectively degraded the β chain of native laminin, whereas plasmin degraded both the and β chains. The specific limited cleavage fragments of laminin produced by -thrombin and plasmin retained the ability to mediate binding of epithelial cells to type IV collagen. These serine proteases failed to degrade native type IV or type V collagen under identical experimental conditions. At 35°C type V collagen, but not type IV collagen, was partially cleaved by both -thrombin and plasmin. Urokinase failed to degrade any of the substrates. It is concluded that thrombin and plasmin could play a physiological role in the degradation of laminin during tissue remodeling or repair. Specific laminin cleavage products produced by these enzymes could be useful in structural, immunological, and biological studies.     

细胞表面半乳糖基转移酶介导外胎盘锥扩展和次生滋养层巨细胞迁移的证据

细胞表面半乳糖基转移酶（ＧａｌＴａｓｅ）是层粘连蛋白（ＬＮ）非整合素类受体，能与其上寡糖链的Ｎ－乙酰葡糖胺（ＧｌｃＮＡｃ）残基识别和结合。作者从妊娠第８．５天雌鼠子宫蜕膜中剥离胚胎，显微分离外胎盘锥（ＥＰＣ）后进行体外培养。用（１）ＬＮ预先半乳糖基化；（２）外源ＧｌｃＮＡｃ底物竞争；（３）ＧａｌＴａｓｅ抗体阻断；（４）α乳清蛋白处理等方法干扰滋养层细胞与ＬＮ的相互作用，均对ＥＰＣ粘附无影响，但抑制ＥＰＣ扩展和次生滋养层巨细胞（ＳＴＧＣｓ）迁移。证明ＧａｌＴａｓｅ虽不参与ＥＰＣ起初的粘附，但通过与ＬＮ寡糖链上ＧｌｃＮＡｃ的结合介导ＥＰＣ扩展和ＳＴＧＣｓ迁移。