being removed from the donor or patient by injection, the stem cells are placed onto the damaged
tissue and mix with their “neighboring cells and [develop] into part of that tissue, replacing
damaged areas and strengthening the organ” (Daddona 1031). This allows the organ to become
partially treated for the better or to be strengthened and cured.
Most believe that pluripotent stem cells are only found in mature tissue. However,
pluripotent stem cells can be found about four days after fertilization. Pluripotent stem cells are
the cells that make up the blastocyst, “a several day year old embryo” (Pavlat 10). At this point in
time, the blastocyst is formed of an outer layer and an inner layer. The inner layer, called the
embryoblast, is composed entirely of pluripotent stem cells. The outer layer, called the
trophoblast, will become the placenta for the baby. The Catholic Church argues that embryonic
stem cell research is unethical because it destroys a human life. “The human embryo dies
immediately when stem cells are extracted from it, since at that stage of life, it is only formed of
stem cells in its internal layer and of the cells that will form the placenta in its external layer”
(Ráez 6).
The Church instead insists on continuing adult stem cell research. Adult stem cells can
come from tissue as young as a fetus. A stem cell belonging to “an older embryo, a fetus, or a
more mature individual is considered to be an adult stem cell” (Condic 1). Like embryonic stem
cells, adult stem cells are pluripotent. They are manipulated to “generate specific cell types so
that they can be used to treat injury or disease” (“Stem Cell Basics”). This technique has resulted
in many accomplishments for adult stem cell research. Adult stem cells have successfully cured
or treated over seventy diseases and conditions (Pavlat 11). A number of these include brain
cancer, Hodgkin’s lymphoma, ovarian cancer, multiple sclerosis, Parkinson’s disease, and
various bone repairs (“Benefits of Adult Stem Cells”). There have been over one thousand two