Single-Cell Electrical Phenotyping Enabling the Classification of Mouse Tumor Samples

Single-cell electrical phenotyping (e.g., specific membrane capacitance (C(m)) and cytoplasm conductivity (σ(p))) has long been regarded as potential label-free biophysical markers in tumor status evaluation. However, previous studies only reported the differentiation of tumor cell lines without classifying real tumor samples using cellular electrical properties. In this study, two types of mouse tumor models were constructed by injecting two types of tumor cell lines (A549 and H1299), respectively. Then tumor portions were retrieved for immunohistochemistry studies and single-cell electrical phenotyping based on home-developed microfluidic platforms. Immunohistochemistry results of tumor samples confirmed the adenocarcinoma and large-cell carcinoma characteristics for A549 and H1299 based tumor samples, respectively. Meanwhile, cellular C(m) and σ(p) were characterized as 2.25 ± 0.50 μF/cm(2) and 0.96 ± 0.20 S/m for A549 based tumor samples (n(cell) = 1336, Mouse I, II, III) and 1.76 ± 0.54 μF/cm(2) and 1.35 ± 0.28 S/m for H1299 based tumor samples (n(cell) = 1442, Mouse IV, V, VI). Significant differences in C(m) and σ(p) were observed between these two types of tumor samples, validating the feasibility of using C(m) and σ(p) for mouse tumor classification.