張育承

學號：608380019 (Yu-Cheng Chang)

論文名稱

應用原子力顯微術於人類肺泡腺體上皮癌細胞之力學性質研究 (Application of Atomic Force Microscopy to Probing Mechanical Properties of Adenocarcinomic Human Alveolar Basal Epithelial (A549) Cells)

關鍵詞

肺腺癌、AFM 原子力顯微鏡、人類肺癌細胞 A549、細胞鬆弛素、赫茲接觸力學模型、圖像數據處理、程式語言設計 (Lung adenocarcinoma, Atomic force microscopy, Human lung adenocarcinoma epithelial cells, Cytochalasin-D, Hertz model, Image data processing, Programming language design)

DOI

https://doi.org/10.6846/TKU.2020.00593

中文摘要

本研究利用 AFM 原子力顯微鏡，對人類肺癌細胞 A549 進行實驗，實驗變因設計為加入細胞鬆弛素 Cytochalasin-D，觀察在加入藥物以後，A549 之力學性質變化為何，以及細胞高度與楊氏模數之分佈狀況。研究主要可分為三個階段，分別為蒐集實驗數據、程式進行計算與擬合、歸納分析之成果。

將實驗後所得到的 JPK-QI-Data 原始檔，讀入專屬於 JPK Nanowizard II 原子力顯微鏡儀器使用的數據分析程式，以赫茲接觸力學模型為基礎，配合探針針尖的參數調整，進行楊氏模數的擬合計算，得到 JPK-QI-Image 圖像檔，再透過 Gwyddion 轉檔程式，使 JPK-QI-Image 得以數值的方式讀入判定細胞邊界之 MATLAB 程式碼中，得到在細胞邊界內的不同屬性的資訊，最後經由直角坐標轉換為極座標，計算出細胞在掃描範圍內與其細胞核之關係，將控制組與實驗組之結果加以歸納。

透過實驗結果之分析，可以獲得以下之結論：一、A549 在加入藥物以後，細胞骨架的微絲結構遭受破壞，細胞高度、楊氏模數之變化同受影響。二、A549 在加入藥物以後，越接近細胞的邊緣，楊氏模數也會隨之變大，且變硬的趨勢較控制組更為明顯，推測與微絲結構受到藥物作用的影響有關。

英文摘要

In this study, an AFM atomic force microscope was used to conduct experiments on human lung cancer cells A549. The experimental variables were designed to add Cytochalasin-D, and observe the changes in the mechanical properties of A549 after adding drugs, as well as the cell thickness and Young’s modulus distributions. The research can be divided into three stages, which are the collection of experimental data, implementation of the data processing program, and the analysis of the resolving results.

The original JPK-QI-Data files obtained in the experiment are systematically imported into the data analysis program dedicated to the JPK Nanowizard II atomic force microscope (AFM) instrument. Based on the Hertz contact mechanics model, the Young’s modulus of the scanned cell samples can be experimentally determined by fitting calculation of AFM indentation curves in conjunction with the parameter adjustment of the probe tips. Before the analysis processes of cellular Young’s modulus, the JPK-QI-Image image files were translated into text-based data of indentation curves for every pixel of the whole scanning field by the Gwyddion transcoding program. The transcoded AFM images were ready to be read and further analyzed by the MATLAB program developed in this study. The attribute information is finally converted into polar coordinates through rectangular coordinates, the relationship between the cell and its nucleus in the scanning range is calculated, and the results of the control group and the experimental group are summarized.

According the experimental results, the following conclusions are obtained: First, through proper data processing, the scanned AFM images can be decoded into individual indentation curves of all scanned surface spots in the cellular areas. Second, after adding drugs to A549, the microfilament structures of the cytoskeleton in the cells are destroyed, and changes of cell height and Young’s modulus are also affected. Third, after the drug is delivered, the Young’s modulus of the cellular regions which are closer to the cell edges are significantly increased.