string: Reproduced from Chen et al. (2013). (E) Working principle of the microengraving array for capture and immunomonitoring of single immune cells. Adapted from Love et al. (2006), Copyright ©2006, with permission from Nature Publishing Group. (F) Photograph and working principle of the single-cell barcode chip for polycytokine analysis of single immune cells. Adapted from Ma et al. (2011), Copyright ©2011, with permission from Nature Publishing Group.