A microfluidic system based on the monoclonal antibody BCMab1 specifically captures circulating tumor cells from bladder cancer patients

Lab-on-a-chip systems for cancer biomarker diagnosis

Lab-on-a-chip (LOC) or micro total analysis system is one of the microfluidic technologies defined as the adaptation, miniaturization, integration, and automation of analytical laboratory procedures into a single instrument or "chip". In this article, we review developments over the past five years in the application of LOC biosensors for the detection of different types of cancer. Microfluidics encompasses chemistry and biotechnology skills and has revolutionized healthcare diagnosis. Superior to traditional cell culture or animal models, microfluidic technology has made it possible to reconstruct functional units of organs on chips to study human diseases such as cancer. LOCs have found numerous biomedical applications over the past five years, including integrated bioassays, cell analysis, metabolomics, drug discovery and delivery systems, tissue and organ physiology and disease modeling, and personalized medicine. This review provides an overview of the latest developments in microfluidic-based cancer research, with pros, cons, and prospects.

Microfluidic devices for glycobiomarker detection in cancer

During oncogenesis, several alterations occur within cells, one of them being the abnormal glycosylation of proteins, resulting in the formation of glycoproteins with aberrant glycan structures, which can be secreted into the blood stream. Their specific association to tumour cells makes them useful indicators (biomarkers) of the oncogenic process and their detection in blood can be employed in different stages of tumour development for early detection, prognosis and therapeutic drug monitoring. Due to the importance of detecting cancer-associated glycoproteins with aberrant glycosylation in blood or serum, analytical methodologies with improved performance are required to ameliorate the laboratorial tests currently used for the detection of these analytes. Microfluidics was created to facilitate the implementation of simple and point-of-care analysis, away from a centralized laboratory. The massive use of microfluidic systems in clinical settings can be seen in pregnancy tests and diabetes control, for example. But what about other clinical domains, such as the detection of glycoproteins with aberrant glycans secreted by tumour cells? Are microfluidic systems helpful in this case? This review analyses the requirements of a microfluidic assay for the detection of low-abundant blood/serum cancer-associated glycoproteins with abnormal glycans and the progresses that have been made in the last years to develop integrated microfluidic devices for this particular application. The diverse microfluidic systems found in literature present, in general, the same analytical performance as the conventional assays but have additional advantages, namely a reduction in assay times, a decrease of sample and reagent consumption and lower costs. The review will also focus on the improvements that are still needed for better biosensing of this type of cancer biomarkers using microfluidic devices.

Top-Down Characterization of an Intact Monoclonal Antibody Using Activated Ion Electron Transfer Dissociation

Monoclonal antibodies (mAbs) are important therapeutic glycoproteins, but their large size and structural complexity make them difficult to rapidly characterize. Top-down mass spectrometry (MS) has the potential to overcome challenges of other common approaches by minimizing sample preparation and preserving endogenous modifications. However, comprehensive mAb characterization requires generation of many, well-resolved fragments and remains challenging. While ETD retains modifications and cleaves disulfide bonds-making it attractive for mAb characterization-it can be less effective for precursors having high m/z values. Activated ion electron transfer dissociation (AI-ETD) uses concurrent infrared photoactivation to promote product ion generation and has proven effective in increasing sequence coverage of intact proteins. Here, we present the first application of AI-ETD to mAb sequencing. For the standard NIST mAb, we observe a high degree of complementarity between fragments generated using standard ETD with a short reaction time and AI-ETD with a long reaction time. Most importantly, AI-ETD reveals disulfide-bound regions that have been intractable, thus far, for sequencing with top-down MS. We conclude AI-ETD has the potential to rapidly and comprehensively analyze intact mAbs.