title: Pipetting-driven microfluidic immunohistochemistry to facilitate enhanced immunoreaction and effective use of antibodies.
abstract: Immunohistochemistry (IHC), which has been used to detect antigens in cells of a tissue section using an immunoreaction between an antibody and an antigen, is a practical tool for identifying the type and stage of diseases in cancer diagnosis and scientific research. However, conventional IHC requires long, laborious process times and high costs. Although microfluidic IHC platforms have been developed to overcome these limitations, the application of microfluidic IHC in real-world environments is still limited due to the additional equipment needed to operate the microfluidic systems. In addition, continuous flow in a microfluidic channel leads to a waste of unbound antibodies. In this study, we demonstrate a novel and easy-to-use microfluidic IHC platform operated only using a manual pipette that is commonly available in research laboratories or hospitals. No other device such as a pump or a controller is required to operate our system. Bidirectional flows of the antibody solution in a microfluidic device are induced by repetitive manual pipetting which facilitates the enhanced antigen-antibody reaction and enables the effective use of a limited amount of antibody. When breast cancer cell and tissue sections are reacted with antibodies using our platform, pipetting for less than 2 min is sufficient to obtain immunostaining results without damaging the sample. The staining intensity by our method is similar to that of the sample stained for 1 h by a conventional batch process. We believe that this pipetting-based approach to the operation of a microfluidic system allows end users to use microfluidic IHC more conveniently and easily in real-world environments.
authors.affiliation: Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea. jekyun@kaist.ac.kr.
authors.forename: Segi
authors.identifier: 0000-0003-3122-1589
authors.initials: S
authors.lastname: Kim
authors.affiliation: Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea. jekyun@kaist.ac.kr.
authors.forename: Seyong
authors.identifier: 0000-0002-0767-1718
authors.initials: S
authors.lastname: Kwon
authors.affiliation: Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea. jekyun@kaist.ac.kr.
authors.forename: Chang Hyun
authors.identifier: 0000-0002-1692-7367
authors.initials: CH
authors.lastname: Cho
authors.affiliation: Department of Bio and Brain Engineering, Korea Advanced Institute of Science and Technology (KAIST), 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea. jekyun@kaist.ac.kr and KAIST Institute for Health Science and Technology, 291 Daehak-ro, Yuseong-gu, Daejeon 34141, Republic of Korea.
authors.forename: Je-Kyun
authors.identifier: 0000-0003-4522-2574
authors.initials: JK
authors.lastname: Park
mesh_terms: D000906:Antibodies / Q000032:analysis / Q000276:immunology; D014408:Biomarkers, Tumor / Q000032:analysis; D001943:Breast Neoplasms / Q000737:chemistry; D045744:Cell Line, Tumor; D006801:Humans; D007150:Immunohistochemistry / Q000295:instrumentation / Q000379:methods*; D061986:MCF-7 Cells; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation / Q000379:methods*
chemical_list: D000906:Antibodies; D014408:Biomarkers, Tumor