Advances in therapeuticcloning reported in the past year have been very exciting.

Somatic cellnuclear transfer (SCNT) can be used to produce very powerful human embryonic stem cells (ESC).

These new cells are called NT-ESCs for short. Neither embryos norreprogramming factors are needed to produce human NT-ESCs.Seehere,hereandherefor discussions of the pioneering papers reporting creation of NT-ESC including the first paper by the lab of Shoukhrat Mitalipov of OHSU, which I called the stem cell event of the year for 2013.

Now that human NT-ESC are a reality, the big question is how good these cells are compared to existing alternatives. For example, can they compete with induced pluripotent stem cells (IPSC) in terms of clinical impact as a basis for regenerative medicine?

Because NT-ESC are extremely difficultto make and have other issues (more on that below), the general sense in the field is that NT-ESC have to be clearly better than IPSCs in some concrete way to be a major, meaningful clinically relevant advance. Otherwise, whats the point of going to all that trouble to make them when IPSCs are relatively so easy to make?

Just a few months ago it seemed that NT-ESC might jump that high hurdle.

Mitalipovs team published aNaturepaper in July (Ma, et al) claiming that NT-ESC are demonstrably superior to IPSC. You read see my review of that paperherein whichI was pretty excited.

However, nowa new, very important paperfrom Dieter Eglis lab just came out in Cell Stem Cellreporting a very different result than that of the Ma paper.The new paper (Johannesson, et al; see graphical abstract above)conclusively shows that NT-ESC and IPSC are extremely similar cell types.So Johannesson, et al say that NT-ESCs are not better than IPSCs.Drs. Mitalipov and Ma are authors on the new paper as well that seems to contradict their own July NT-ESC paper.

We are left with a dilemma.

Read the original here:
Somatic Cell Nuclear Transfer | Knoepfler Lab Stem Cell Blog