Diagnosis of immediate-type allergy using surface plasmon resonance

Surface plasmon resonance (SPR) sensors can sensitively detect refractive index (RI) changes in living cells on the surface of a sensor chip, without labeling, in real time. We and other groups have applied SPR and SPR imaging (SPRI) sensors for cell-based clinical diagnosis, such as allergies and cancer. Herein, we review techniques using SPR and SPRI sensors for the label-free detection of RI changes in living cells. We then focus on applications of SPRI techniques for the clinical diagnosis of immediate-type allergy (type I allergy) and introduce new techniques using basophil separation chip for SPRI and a human IgE receptor expressing mast cell line.