可進行免疫磁珠標定單細胞捕捉之磁性微流井微流道晶片

A Microfluidic Device Integrating Microwell with Permanent Magnet System for Immunomagnetic Single Cell Trapping

黃郁蓁(Yuh-Jen Hwong)

指導教授 ： 黃念祖

國立臺灣大學/電機資訊學院/生醫電子與資訊學研究所/碩士(2017年)

https://doi.org/10.6342/NTU201801968

摘要

在人類血液中的白血球源自於造血幹細胞，主要負責人體的免疫反應。它的種類繁多，可由功能及表現分成不同亞群，且是一種異質性 (Heterogeneity) 很高的細胞族群。異質性代表每個單獨的細胞都存在基因、特性及表現上的差異。根據研究發現其可能是造成疾病復發或無法根治的原因，目前傳統群體分析的技術只能觀察到細胞的綜合表現，忽略細胞之間的差異。所以針對此類細胞而言，單細胞分析 (Single-cell analysis) 格外重要。
微流道是一種在微米尺度上操作流體的技術，具有體積小、價格低廉、可處理低濃度樣本等優點。其中結合磁外力的微流道系統 (Microfluidic immunomagnetic assay) 更具備了兩項優勢，特別適合運用在分離白血球亞群上：其一，相對於流體動力學以結構進行分離，會受到樣本間尺寸大小差異的限制，磁珠運用抗體抗原原理進行標定的技術使它能夠從同尺寸大小的白血球亞群 (White blood cell subpopulation) 中篩選出目標細胞；其二，相對於光學或介電泳法，磁場外力非直接接觸細胞，研究顯示能保有大部分(~100%) 細胞活性，利於後續的觀察及分析。然而，被捕捉在晶片上的細胞通常不規則的分散並有聚集的情形，不能直接做單細胞分析。若欲對捕捉的細胞進行單細胞分析，則需轉移到合適的單細胞捕捉平台，而這個過程須承擔細胞損失或遭受污染的風險。
為提供一個可快速從血液或病液中分離出特定白血球亞群，並進行單細胞分析的微流道晶片，本研究開發一結合磁力及微流井 (Microwell) 的微流道系統，旨在將細胞分離及單細胞捕捉的功能結合在同一個晶片上。未來期望此系統可直接讓使用者通入微量病液或血液，快速篩選出目標細胞並以單顆細胞的解析度捕捉於晶片上，提供一個在原位觀察及分析單細胞的平台，並減少原本從細胞分離裝置轉移到單細胞分析平台所需消耗的人力以及降低細胞受到污染或損失的風險。相信此整合性微小化的生醫晶片有潛力提供病患免疫狀態監控、疾病早期偵測及癌症預防的服務。

關鍵字

單細胞捕捉 ； 磁力 ； 微流井 ； 微流道系統

並列摘要

White blood cells (WBC) are important components of the immune system in a human body, responsible for protection against bacteria, viruses and invading parasites. The proportion, counts and cytokine production activities of the leukocyte subsets alternate in the presence of infections, malignancies, inflammation and so on, which indicates that the quantitative and qualitative understanding of white blood cell subpopulation can facilitate the diagnosis of various diseases.
Single cell analysis can be used to identify the subtypes of heterogeneous immune cells population, which leads to precise immune status monitoring. To achieve single cell analysis, cell separation and single cell trapping technique are essential to acquire the target cells for investigation. Microfluidic immunomagnetic assay is a preferable cell separation platform as the gentle, non-direct contact of the magnetic force preserves the viability of the cells while biomarker-based labeling can ensure high specificity cell separation. However, due to the characteristics of a magnet, the target cells are usually trapped in clusters, therefore to achieve single cell analysis, transportation to another suitable platform is necessary. However, this risks cell contamination and cell loss.
To address the above problem, we designed a microfluidic device chip integrating microwell and permanent magnet system to enable highly specific immunomagnetic single cell trapping. With the function of signal cell counting and further analysis, the device can potentially provide useful information to facilitate rapid and accurate analysis of immune status monitoring or early-stage autoimmune disease or cancer diagnosis.

並列關鍵字

single-cell trapping ； microfluidic immunomagnetic assay ； microwell

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