Cord Banking and iPS Cells

Umbilical Cord Banking (UCB) has been a popular discussion topic in the United States since the first Cord Bank was established in New York in 1992. Since the first cord blood transplantation in 1988, there have been over 780,000 UCB donations to private banks and 400,000 UCB donations to public blood banks worldwide. There has been such a great number of donations because UCB is full of hematopoietic progenitor cells, which makes it a more desirable solution to genetic, metabolic and immune disorders, over bone marrow and blood. Because of the nature of UCB, the recipient does not need to be an immunological match, there is a lower rate of infection and it is much easier to acquire than bone marrow, making it the ideal form of treatment for many patients and practitioners.

Over twenty years later, a new technology is emerging that could provide some clarity to the “to donate or not to donate” debate: induced pluripotent stem cells (iPSC). Derived from adult cells, iPSCs have the potential to be used like UCB or reprogrammed into specific tissue like myocytes. This potential opens up banking to countless individuals born before 1992, who never had an option to bank their UCB. With this unbounded potential, should iPSCs be banked liked UCB? Supporters argue that there has been enough evidence thus far to start a bank, however, most people seem to agree that too much is unknown about iPSCs and their use in humans. With that, most are in agreement that iPSC research is absolutely needed so banking can become a reality in the future.

For now iPSCs will remain in the testing and research phase, however, based on current research, iPSCs have the potential to enhance Cord Blood that has already been banked, perhaps providing some relief to public banks in the future (Broxmeyer, 2010). Though the potential of iPSCs is endless, more work has to be done before they are placed in humans and considered a viable banking system.

Tags: Cord Blood, ESCs, iPS, Stem Cell Banking, stem cells

FAQ About Feeder Cells for Stem Cells –Part One

The cost of preparing feeder cells for induced pluripotent stem cells (iPSCs) or embryonic stem cells (ESCs) is mainly due to 1. serum and media, 2. labor for growing and treating cells, and 3. expenses for freezing media and vials. Ready-to-use feeder cells saves one important labor-intensive step of iPSC generation, it should be an important help for iPSC and stem cell researchers. We know that most of our colleagues are tired of preparing fresh early passages of MEFs and treating them with expensive mitomycin C or finding an irradiator to pre-treat the MEFs. A lot of iPSC researchers lost iPS stem cells due to the lack of patience in handling MEF feeders. The offering of Allele’s feeder cell product line is really an easy solution and convenience to iPSC researchers.

Question 1: There are companies offering drug-resistant feeder cells such as MEF cells expressing neo-, puro-, or hygromycin-resistance genes. Is it important to have such drug-resistance genes when choosing feeder cells?

Adding drug resistant markers to these cells should not be necessary because iPSCs grown on feeder cells are usually not cultured in antibiotics-containing medium. The feeder cells will not be selected by drug resistance nor will they contaminate iPS cells since they can not propagate after irradiation. However, for those who do need to use drug selection for any reason, we will provide drug-resistant feeder cells upon request.

Question 2: There are publications showing the use of cells lines as feeder cells instead of primary fibroblasts, e.g. SL10, MRC-5, STO. Are there any advantages of using these cell lines?

Not really. Handling primary cells requires certain amount of experience and may be tedious; using cell lines, on the other hand, would be easier for preparing feeder cells. We provide feeder cells from immortalized early passage human foreskin fibroblasts at prices often lower than those from cell lines.

Question 3: Should I choose fluorescent protein expressing feeder cells for easy separation from iPSCs?

You do not need to include fluorescent protein in feeder cells, as feeder cells are quite different in morphology from iPS cells or ES cells. In fact, many labs use iPS factors that are co-expressed with fluorescent markers, in which cases feeder cell expressed fluorescent proteins will confuse the readout.

Question 4: What are the main advantages of using bFGF-expressing feeder cells?

Our bFGF-feeder cells not only eliminate the needs for added recombinant bFGF to stem cell cultures, but also form very nice cell lawn to serve iPSC colony formation because of their strictly controlled passage and growth conditions. We have used these cells without coating dishes with gelatin and obtained nice iPSC colonies.

Preview: Next Part of FAQ on Feeder Cells: choosing mouse or human fibroblasts, selecting iPSC colonies…

Announcement: An audience-orientated User Forum will be added to Allele Biotech webpages so that people can freely discuss or review products and technologies. A distilled version of discussions will be presented in a related but separate FAQ section, which will also include all Allele eNewsletters sent to our contacts about every quarter. Look for the links on www.allelebiotech.com in coming weeks.

Tags: bFGF, biology FAQ, biology forum, biotech enewsletter, ES cells, ESC, ESCs, feeder cells, human fibroblasts, iPS cells, iPSC, iPSCs, irradiation, MEF, MEFs, mitomycin C, stem cell culture