Catholic Medical Quarterly Volume 70(3) August 2020

Mass Production of Human “Embryoid” Cells from Developmentally Frozen Embryos: Is it Ethical?

The Rev. Patrick Pullicino, M.D, Ph.D., the Very Rev. Edward J. Richard, M.S., V.F., J.D., D.Th.M. and William J. Burke, M.D, Ph.D.

They point out that there has been a rush to approve induced pluripotent stem (iPS) cells which have been touted as the ethical alternative to using human embryonic stem cells for regenerative medicine. These are cells capable of differentiating into all cell types in the adult organism and were initially obtained from differentiated adult cells using a combination of transcription factors. The US Conference of Catholic Bishops (USCCB) state “the goal sought for years through failed attempts at human cloning - the production of pluripotent stem cells that are an exact match to a patient - has been brought within reach by an ethical procedure” (USCCB 2007). One Catholic ethicist states “embryonic stem cells have no moral status” (Wade 2007). We have however expressed that caution is needed before openly accepting these new stem cell procedures, (Burke, Pullicino, and Richard 2007, 204).

However, the authors question the ethicality of the stem cell procedure. They state that “A careful examination of the MPEC procedure shows that the embryo-like structures produced in the procedure, (from either ESCs or iPS cells) are ontologically indistinguishable from embryos. These embryos are prevented from reaching their full potential by depriving them of the extra-embryonic cells required for implantation into the uterus, and if they, along with the extraembryonic cells, were implanted into a surrogate uterus, could develop into a living human infant.”

In mice, both late stage mouse embryos and live born mice have been produced using mouse iPS cells. If the same procedures were applied to human somatic cells, there is every reason to believe that human infants could be produced. The point being that while iPSCs are described as pluripotent, they are in fact, totipotent: “capable of developing into a complete organism” or “differentiating into any of its cells or tissues”

They therefore conclude that “Firstly, the production of iPS cells is not morally neutral.”. iPS cells are ontologically and morally the same as embryos. Secondly, “the newly established ability to scale production of multiple embryos from iPS or ESCs breaks new ethical ground. Great caution is needed.”


  • Richard E, Burke W, Pullicino P.  Mass Production of Human “Embryoid” Cells from Developmentally Frozen Embryos: Is It Ethical? The Linacre Quarterly. 2020. 87(3), 347-350