ASM-chip: an antibody-modified size-screening microfluidic chip for high-efficiency circulating glioma cell isolation and clinical application

Peripheral blood circulating glioma cells (CGCs) are crucial for glioma screening, prognostic evaluation, and diagnostic applications. However, reliable methods for efficient CGCs capture and comprehensive clinical evaluation on whether CGCs could faithfully represent complicated heavy equipment (such as MRI) remain insufficiently explored. Here, we present an antibody modification and size screening-based microfluidic (ASM) chip for effectively capturing CGCs, specifically designed for potential clinical translational applications. The ASM chip consists of one inlet, three outlets, one white blood cell clearance area, and one CGC capture area. The performance of the chip was optimized with two typical cell subtypes, namely SU-DHL-4 (to simulate leukocytes) and U251MG-ZsGreen (to simulate CGCs), and the capture rate reached more than 96% at a flow rate of 1.2 mL/h. In real-life applications, CGCs (1-25/mL) were detected in 21 out of 35 glioma patients. We found that the number of CGCs was relatively high in patients with wild-type IDH1 and was positively correlated with Ki67 expression (p = 0.026). The enrichment of CGC was correlated with neutrophils (p = 0.041) and heparin-binding protein (p = 0.0064), suggesting neutrophil-mediated metastasis. Radiomics linked a higher presence of CGCs with larger tumors, severe necrosis, and extensive edema, suggesting a poor prognosis for patients. The ASM chip can effectively capture and quantify CGCs for guiding the diagnosis and predicting the potential prognosis of clinical glioma patients.