STEM CELL THERAPY

Stem Cell Therapy

Stem Cell Therapy

Introduction

Few topics in science and religion have been as hotly contested in recent years as stem cell research, largely because it involves the fate of, disposition of, and research on the human embryo. There are two basic types of stem cell research—that involving adult cells (AS cells) and that involving human embryonic cells (ESCs or hES cells); only the latter is a source of controversy. In both cases, research is still at the early stages regarding the programming and uses of these cells, and there is comparatively little data about the efficacy of AS and hES cells for human therapies. That is why most scientists agree that, in the United States, government funding should be widely available for research on both types of stem cells, an issue that has been contested in the U.S. Congress.

Stem Cell Therapy: A Discussion

Cibelli (2002) mentions that stem cells are unspecialized and so are able to renew indefinitely; they also have the capacity to differentiate into specialized cells. In humans, these cells are found in some adult organs, in blood, and in bone marrow; in the inner cell mass of the human embryo at the blastocyst stage (five to six days after fertilization); on the gonadal ridge of aborted or miscarried fetuses; and in the placenta and umbilical cord (hematopoetic stem cells).

Because stem cells have the capacity to regenerate, particularly ESCs, they have ushered in the era of "regenerative medicine," signaling that, in theory, these cells can be used to regenerate human tissues and cells, and ultimately increase quality of life and the human life span (Cibelli, 2002). Embryonic stem cells are the progenitor cells for the human body and at their earliest stage (the blastocyst stage) they are completely undifferentiated and can give rise to any cell type in the human body (totipotent, pluripotent, and multipotent are all terms that have been used to describe this phenomenon). At this stage the cells have not yet received their "marching orders" for what they will become; therefore, scientists have been experimenting with controlling the programming of ESCs in culture in order to direct their ends (controlled differentiation) to specialized cells such as blood, skin, and nerve cells.

In order to extract these embryonic stem cells, scientists must collapse the trophectoderm that surrounds the blastocyst in order to get the stem cells from the inner cell mass (ICM) where they reside within the blastocyst or pre-embryo. Such a technique destroys the pre-embryo and renders it incapable of implantation in the uteran wall. This is the crux of the ethical problem for those who oppose embryonic stem cell research.

Studies in 2001 and 2002 indicate the potential for primate parthenotes to form embryonic stem cells and to develop a variety of differentiated cell types in culture. Parthenotes are embryos that grow from unfertilized eggs (chemically tricked into fertilizing and retaining the full choromosomal complement) that are (Holland, Lebacqz and Zoloth, 2001), so far as is known, incapable of becoming viable fetuses in primates and ...