Impedance-Based Living Cell Analysis for Clinical Diagnosis of Type I Allergy

Abstract

Non-invasive real time evaluation of living cell conditions and functions are increasingly desired in the field of clinical diagnosis. For diagnosis of type I allergy, the identification of antigens that induces activation of mast cells and basophils is crucial to avoid symptoms of allergic diseases. However, conventional tests, such as detection of antigen-specific IgE antibody and skin tests, are either of low reliability or are invasive. To overcome such problems, we hereby applied an impedance sensor for label-free and real-time monitoring of mast cell reactions in response to stimuli. When IgE-sensitized RBL-2H3 cells cultured on the electrodes were stimulated with various concentrations of antigens, dose-dependent cell index (CI) increases were detected. Moreover, we confirmed that the impedance sensor detected morphological changes rather than degranulation as the indicator of cell activation. Furthermore, the CI of human IgE receptor-expressing cells (RBL-48 cells) treated with serum of a sweat allergy-positive patient, but not with serum from a sweat allergy-negative patient, significantly increased in response to purified human sweat antigen. We thus developed a technique to detect the activation of living cells in response to stimuli without any labeling using the impedance sensor. This system may represent a high reliable tool for the diagnosis of type I allergy.

Flow length-dependent evaluation of separation and concentration functions of microfluidic chips for allergy testing using pseudo-cells

“…The allergen response of the patients' basophils has been measured, and its correlation with the disease has been studied using surface plasmon resonance imaging (SPRI) sensors [1][2][3][4][5][6][7] and impedance sensors. 8,9) In order to detect basophils, they must be separated from the other leukocytes. As a cell separation method, the MACS system [10][11][12][13][14][15] (Miltenyi Biotec) is used in separating magnetically labeled cells by magnetic force.…”

Development of SPR Imaging-Impedance Sensor for Multi-Parametric Living Cell Analysis

“…The SPRI sensor could visualize the change of RI distribution induced by treatment with various stimuli, which are inhibitors at single cell levels [15,16,17,18,19]. On the other hand, impedance sensors detect living cell-based impedance changes on an electrode which specifically reflects the attachment and adhesion area of living cells on the electrode at around 10 kHz [20]. We previously reported that impedance sensors (iCELLigence, ACEA Biosciences, Inc., San Diego, CA, USA) can detect changes of the adhesion area of living cells such as RBL-2H3 cells and vascular endothelial cells (HUVECs) at 10 kHz in response to stimuli without any labeling [20,21].…”

“…On the other hand, impedance sensors detect living cell-based impedance changes on an electrode which specifically reflects the attachment and adhesion area of living cells on the electrode at around 10 kHz [20]. We previously reported that impedance sensors (iCELLigence, ACEA Biosciences, Inc., San Diego, CA, USA) can detect changes of the adhesion area of living cells such as RBL-2H3 cells and vascular endothelial cells (HUVECs) at 10 kHz in response to stimuli without any labeling [20,21]. Moreover, we applied the technique for mast cells reaction-based clinical diagnosis of type I allergy [20].…”