Automated cell isolation from photodegradable hydrogel based on
fluorescence image analysis
Abstract
We report an automated cell-isolation system based on fluorescence image
analysis of cell aggregates cultured in a photodegradable hydrogel. The
system incorporates cell culture in a humidified atmosphere with
controlled CO 2 concentration and temperature, image
acquisition and analysis, micropatterned light exposure, and cell
collection by pipetting. Cell aggregates were cultured on hydrogels, and
target cells were selected by phase contrast and fluorescence image
analysis. After degradation of the hydrogel by exposure to
micropatterned ultraviolet light, cell aggregates were transferred to a
collection vessel by robotic pipetting. We assessed the system for
hydrogel degradation, recovery of target cells, and contamination by
off-target cells. We demonstrated two practical applications of our
method: (i) in cell aggregates from MCF-7-RFP strains in which 18.8% of
cells produced red fluorescent protein (RFP), we successfully obtained
14 proliferative fluorescence-positive cell aggregates from 31 wells,
and all of the isolated strains produced a higher proportion of RFP than
the original populations; (ii) after fluorescent immunostaining of human
epidermal growth factor receptor 2 (HER2) in cancer cells, we
successfully isolated HER2-positive cells from a mixed population of
HER2-positive and -negative cells, and gene sequence analysis confirmed
that the isolated cells mainly contained the target cells.