Passaging HuES Human Embryonic Stem Cell-lines with Trypsin.

Summary

In this video we demonstrate how our lab routinely passages HuES human embryonic stem cell lines with trypsin. Brought to you by JoVE.

Abstract

In this video we demonstrate how our lab routinely passages HuES human embryonic stem cell lines with trypsin. Human embryonic stem cells are artifacts of cell culture, and tend to acquire karyotypic abnormalities with high population doublings. Proper passaging is essential for maintaining a healthy, undifferentiated, karyotypically normal HuES human embryonic stem cell culture. First, an expanding culture is washed in PBS to remove residual media and cell debris, then cells are overlaid with a minimal volume of warm 0.05% Trypsin-EDTA. Trypsin is left on the cells for up to five minutes, then cells are gently dislodged with a 2mL serological pipette. The cell suspension is collected and mixed with a large volume of HuES media, then cells are collected by gentle centrifugation. The inactivated trypsin media mixture is removed, and cells resuspended in pre-warmed HuES media. An appropriate split ratio is calculated (generally 1:10 to 1:20), and cells re-plated onto a 1-2 day old plate containing a monolayer of irradiated mouse embryonic fibroblast feeder cells. The newly seeded HuES culture plate is left undisturbed for 48 hrs, then media is changed every day thereafter. It is important not to trpsinize down to a single cell suspension, as this increases the risk of introducing karyotypic abnormalities.

Protocol

General

We recommend thawing no more than one sample at a given time to ensure easy handling. The handler should take care not to leave cultures at room temperature and low CO2 for long periods of time. All centrifugation of live cells is done at 500-600 x g for 5 min at room temperature.

MEFs (Mouse Embryonic Feeder Cells)

1. Pre-warm MEF media to 37°C. Remove MEF vial from -80°C and immediately submerge the bottom half of tube in a 37°C water bath. It should take about 30-45 seconds before the cells are 80% thawed (small frozen portion left).
2. Quickly bring the tube to the laminar flow....

Discussion

In this video we demonstrated how we routinely passage HuES human embryonic stem cell lines in our laboratory. Efficient and regular splitting and passaging is essential for maintaining a healthy human embryonic stem cell line. Trypsin mediated passage is a significant advantage of HuES cell lines, however, it is important not to over trypsinize cultures or to have a large proportion of single cells during re-platting.

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Materials

List of materials used in this article

Name	Company	Catalog Number	Comments
HuES media 651.5 ml
KO-DMEM 500 ml
PenStrep 6.5 ml
GlutaMAXTM 6.5 ml
NEAA 6.5 ml
2-mercapt–thanol 0.5ul
KO Serum Replacement 65 ml
Plasmanate 65 ml
bFGF2 (10 ng/mL final) 0.65 ml