Rapid micro-immunohistochemistry

We present a new and versatile implementation of rapid and localized immunohistochemical staining of tissue sections. Immunohistochemistry (IHC) comprises a sequence of specific biochemical reactions and allows the detection of specific proteins in tissue sections. For the rapid implementation of IHC, we fabricated horizontally oriented microfluidic probes (MFPs) with functionally designed apertures to enable square and circular footprints, which we employ to locally expose a tissue to time-optimized sequences of different biochemicals. We show that the two main incubation steps of IHC protocols can be performed on MDAMB468-1510A cell block sections in less than 30min, compared to incubation times of an hour or more in standard protocols. IHC analysis on the timescale of tens of minutes could potentially be applied during surgery, enabling clinicians to react in more dynamically and efficiently. Furthermore, this rapid IHC implementation along with conservative tissue usage has strong potential for the implementation of multiplexed assays, allowing the exploration of optimal assay conditions with a small amount of tissue to ensure high-quality staining results for the remainder of the sample. Microfluidics: Rapid immunohistochemistryA new microfluidic device enables immunohistochemistry analysis of tissue within minutes. Immunohistochemistry is a quantitative approach for the analysis of antigens in tissue sections, such as for the detection of cancer. Antibodies are introduced to the tissue that bind to specific antigens, enabling their detection. However, speeding up the diagnosis process, or detecting multiple antigens at one time, is challenging due to the complexity of antibody reactions with antigens. Here, a team from IBM Research Europe report an improved microfluidic process for immunohistochemistry. By using a horizontally oriented microfluidic probe they are able to speed-up reaction rates for the assay and switch between different processing liquids. This allows them to reduce the main incubation step time from an hour to less than 30 minutes.