上泌尿道感染常會引發腎臟急性發炎症狀，嚴重時會導致器官衰竭甚至是死亡，所以此種疾病相關產生之細胞免疫反應是個不容忽視的課題。在先前關於腎臟的微流體晶片研究中，大多數團隊著重於研究慢性腎臟疾病與離子交換等功能。在此研究中，我們利用微機電技術製作一個微流體晶片，用以模擬腎臟在受到細菌入侵時引發的免疫反應，觀察腎臟細胞分泌出的激素對免疫細胞之影響。此晶片利用矮結構控制流場藉以隔離兩種細胞，同時整合了介電泳細胞排列技術(DEP)來定義腎臟細胞之排列圖案。
　　本研究使用來自大腸桿菌(E. coli)的脂多醣(LPS)來刺激腎小管上皮細胞(HK-2)，而HK-2在接受到刺激後，會開始分泌細胞激素去影響人類單核球細胞(THP-1)，之後即可觀察THP-1是否會因為接收到HK-2細胞激素而分化成巨噬細胞。
　　實驗結果顯示HK-2細胞在經由DEP排列後仍有大於99%之存活率，且在培養48小時後確認DEP並不會影響後續生長之細胞型態。在加入10ng/ml E. coli LPS刺激後，HK-2分泌之細胞激素MCP-1濃度有顯著提升，其中經由DEP排列後的實驗組MCP-1分泌量高於未排列的組別約30%。另一方面， LPS刺激HK-2後分泌之細胞激素會使部分THP-1細胞分化而貼附在晶片底面，且其形態也接近使用phorbol-12-myristate-13-acetate (PMA)單獨刺激而分化之巨噬細胞。

Upper urinary tract infections (upper UTIs) can induce acute inflammation of human kidney, which can cause fever, vomiting or even kidney failure and death. Therefore, realizing the immune response of upper UTIs should be helpful for curing this kind of diseases efficiently. In this research, we developed a microfluidic chip model for mimicking the microenvironment of kidney by using MEMS technology. The goal of this research is to observe immune response between kidney and immune cells. The dielectrophoresis (DEP) was utilized in our microchip for building biomimetic pattern of kidney cells.
Lipopolysaccharide (LPS) from Escherichia coli (E. coli) was used to stimulate renal tubular epithelial cells (HK-2). After being stimulated, the HK-2 started to secret some cytokine to influence the human acute monocyte leukemia cell line (THP-1). We observed whether THP-1 cells differentiated to macrophage or not.
Experimental results show that the viability of HK-2 cells is still above 99% and the cells can proliferate for at least 3 days without any morphological change after DEP patterning. The concentration of MCP-1 increased after HK-2 cells were stimulated by 10ng/ml E. coli LPS. Furthermore, MCP-1 concentration secreted by the patterned HK-2 cells was about 30% higher than that from non-patterned HK-2 cells after 72 hours culturing. THP-1 cell adhesion was observed by culturing with LPS-induced HK-2 cytokine for 24 hours.

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