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Protein glycosylation, a critical post-translational modification, influences the stability, efficacy, and immunogenicity of recombinant proteins, including biopharmaceuticals. Glycan structures exhibit significant heterogeneity, varying with production cell types, culture conditions, and purification methods. Consequently, monitoring and evaluating the glycan structures of recombinant proteins is vital, particularly in biopharmaceutical production. The lectin microarray, a technique complementary to mass spectrometry, boasts high sensitivity and ease of use. However, it typically requires more than a day to yield results. To adapt it to non-glycoscience research or drug product process development, an automated, high-throughput alternative is needed. Therefore, the world's first fully automated lectin-based glycan profiling system was developed, utilizing the "bead array in a single tip (BIST)" technology concept. This system allows for the preparation and storage of lectin-immobilized beads in units of 1,000, with customizable parallel insertion orders for various purposes. This article presents a practical protocol for research involving "glyco-qualified" recombinant proteins. After testing their reactivity against 12 polyacrylamide-glycan conjugates, 15 lectins were selected to increase the system's versatility. In addition, the sample labeling process was optimized by switching from Cy3 to biotin, reducing the overall processing time by 30 min. For immediate data qualification, lectin-binding signals are displayed as a dotcode on the top monitor. The system's reliability was confirmed through day-to-day reproducibility tests, repeatability tests, and long-term storage tests, with a coefficient of variation of <10%. This user-friendly and rapid glyco-analyzer has potential applications in the quality monitoring of endogenous glycoproteins for biomarker evaluation and validation. This method facilitates analysis for those new to glycoscience, thereby broadening its practical utility.

An abnormal elevation in pressure is a serious complication involving the extracorporeal circulation circuit. Clot formation might be associated with this complication, but the precise mechanism of an abnormal elevation in pressure has not been identified. We investigated sufficient conditions for in-circuit elevation in pressure using an ex vivo re-circulation circuit with porcine blood. Specifically, we investigated the effect of blood conditions, the type of anticoagulation, and pro-inflammatory stimulation on in-circuit pressure. We also examined the cause of an abnormal elevation of in-circuit pressure by specifically degrading DNA, RNA, or protein components of an obstructed filter and by using immunofluorescent techniques. Neither a change in temperature nor change in pH in the blood increased in-circuit pressure. In contrast, long-term storage of blood, pro-inflammatory stimulation by phorbol myristate acetate, and heparin administration significantly increased in-circuit pressure. Abnormal in-circuit elevation in pressure was associated with deposition of extracellular DNA on the outlet surface of the filter. Administration of DNase resulted in a rapid decline of in-circuit pressure. In an ex vivo re-circulation circuit system, extracellular DNA deposition on the filter is responsible for an abnormal in-circuit elevation in pressure. Senescent leukocytes, stimulated leukocytes, and heparin exposure are associated with extracellular DNA deposition.