Study for both the establishment of in vivo model system for the development of salivary mucous cyst and its treatment

检测渗出性粘液囊肿腔腔液中基质金属蛋白酶-2、-9(MMP2、MMP9)的含量。与来自沃顿管的唾液相比，腔液显示出高水平的基质金属蛋白酶活性。这一结果表明，蛋白水解酶参与了粘液囊肿的发病过程。因此，在上述观察的基础上，我们尝试在体内构建囊状结构，并分析了病变发生的分子机制。将SV40永生化的正常人唾液腺细胞(NS-SV-DC)以1 ng/ml或5 ng/ml浓度的转化生长因子-β1处理后，与Matrigel共接种于裸鼠背部，可形成含有腔液的大囊状结构。囊腔内腔液分析显示有较高的基质金属蛋白酶活性。Northern印迹分析显示，经转化生长因子-β1处理后，细胞内的转化生长因子-β1和基质金属蛋白酶-2的mRNAs表达显著增强。此外，在Matrigel中加入TIMP-1几乎完全抑制了包囊的形成。因此，这些发现表明，转化生长因子-β1处理的细胞体内囊泡的形成与基质金属蛋白酶-2活性的持续诱导有关。

We have examined the content of matrix metalloproteinase-2 and -9 (MMP-2, MMP-9) in luminal fluid of extravasation mucoceles. The luminal fluid showed a high level of MMP activity compared with saliva from Wharton's duct. This result suggests that proteolytic enzymes are involved in the pathogenesis of mucoceles. Thus, based on the above observation, we attempted to construct a cyst-like structure in vivo, and analyzed molecular mechanisms in the development of the lesion. When SV40-immortalized normal human salivary gland cells (NS-SV-DC) were treated with TGF-beta1 at the concentration of 1 ng/ml or 5 ng/ml followed by co-inoculation with Matrigel into the backs of nude mice, they formed large cystic structures containing luminal fluid. Analysis of luminal fluids contained in cystic cavity demonstrated a high MMP activity. Northern blot analysis indicated that expression of TGF-beta1 and MMP-2 mRNAs in cells was greatly enhanced by treatment with TGF-beta1. Furthermore, the development of cyst formation was almost completely inhibited by the addition of TIMP-1 into Matrigel. These findings, therefore, suggest that the in vivo cyst formation by TGF-beta1-treated cells is associated with the continuous induction of MMP-2 activity.