Nano-Mechanics and Membrane Receptor Mapping of CD8 + T Cells (Supplementry Material)

The investigation of nano-mechanical properties and nano-architectures of CD8 + T cells activated in vitro will help further interpret the immune response/recognition of these cells at nanoscale resolution. In this work, the local biophysical properties of human peripheral blood CD8 + T cells were obtained, revealing the adhesion force of membrane was increased after CD8 + T cells were stimulated with phorbol dibutyrate plus ionomycin, though the measured local stiffness for resting and activated cells was similar. The 3-D distribution pattern and grayscale map together revealed that membrane receptors (CD8 and activation marker CD69) distributed non-uniformly on the membrane and were shown as micro-, nano-scale clusters or domains. This work describes a relatively simple approach for exploiting the distribution pattern of receptor molecules on a single T cell surface.