Stem Cell Stem Cell ResearchResearch

Health Law and BioethicsProf. Dr. Helena Pereira de Melo

Lena Jasmin Seiberlich

WWhat are Stem Cells?hat are Stem Cells?

can can develop into many different cell types in the bodydevelop into many different cell types in the body

they serve as a sort of internal repair system, dividing they serve as a sort of internal repair system, dividing essentially without limit to replenish other cells essentially without limit to replenish other cells

wwhen a stem cell divides, each new cell has the hen a stem cell divides, each new cell has the potential either to remain a stem cell or become potential either to remain a stem cell or become another type of cell with a more specialized function another type of cell with a more specialized function

Embryonic and Embryonic and AAdult dult SStem tem CCellsells

Adult Stem Cells:

undifferentiated, found among differentiated cells in a tissue or organ

can renew itself and can differentiate to yield some or all of the major specialized cell types of the tissue or organ

primary roles in a living organism: to maintain and repair the tissue in which they are found

Embryonic Stem Cells:Embryonic Stem Cells:

able to develop into almost any cell in the human body

found in blastocysts

when a fertilized egg has undergone cell division for 5 days it forms a hollow ball of cells (blastocyst). The Embryonic Stem (ES) Cells are derived from this

DifferencesDifferences

Unlike ES cells, which are defined byUnlike ES cells, which are defined by their origin (cells their origin (cells from the preimplantation-stage embryo), adult stem cells from the preimplantation-stage embryo), adult stem cells can be gained from nearly every organ. can be gained from nearly every organ.

DDifferent abilities in the number and type of differentiated ifferent abilities in the number and type of differentiated cell types they can become. ES cells can become all cell cell types they can become. ES cells can become all cell types of the body because they are pluripotent. Adult types of the body because they are pluripotent. Adult stem cells are thought to be limited to differentiating into stem cells are thought to be limited to differentiating into different cell types of their tissue of origindifferent cell types of their tissue of origin

Adult stem cells are not that powerful than ES cells. They Adult stem cells are not that powerful than ES cells. They can transform to different blood cells but not to nerve or can transform to different blood cells but not to nerve or muscle cellsmuscle cells

Research and ResultsResearch and Results

in order to derive or extract the stem cells in order to derive or extract the stem cells found within the embryo, the embryo is found within the embryo, the embryo is destroyeddestroyed in the removal process in the removal process

offers the hope of cell-replacement therapy offers the hope of cell-replacement therapy for diseases such as Parkinson disease, for diseases such as Parkinson disease, diabetes and cardiac myopathy, but diabetes and cardiac myopathy, but formidable scientific and clinical challenges formidable scientific and clinical challenges must be overcome before such therapies must be overcome before such therapies could become availablecould become available

Stem Cells and CloningStem Cells and Cloning Nuclear transfer: involves replacing Nuclear transfer: involves replacing the nucleus of

an egg cell with that from a cell from the patient’s body, and allowing it to develop to form a blastocyst

Cells from the interior of the ES cell would then be harvested and used to establish an ES cell line that has the genetic makeup of the patient. These cells would then be directed to develop into the tissue needed for transplant. This tissue would display the same antigen markers as the patient’s, and therefore would not be rejected

Ethical an judical point of viewEthical an judical point of view

moral dilemma:It forces us to choose between two moral principles:The duty to prevent or alleviate suffering The duty to respect the value of human life

when does human life starts and when does the protection of human dignity and the right to life relating to constitutional law begin?

must be considered the benefit of embryonic stem cell research

other major ethical issue:combination of ES cell and cloning technologies leading to generation of an embryo that is a

genetic clone of the donor of the nucleus

the embryos are genetic clones of the patient, and thus the embryos are genetic clones of the patient, and thus could, in theory, be used to generate a new humancould, in theory, be used to generate a new human

SteStem Cells in context of the m Cells in context of the WorldWorld

The Portuguese Council of Ministers approved a bill of law on February 24, 2011, regulating the use of stem cells for human research on the prevention, diagnosis, and detection of the origin and treatment of degenerative diseases and diseases that cause irreversible destruction of tissues and organs

In Germany the production of human embryos for extraction of stem cells is forbidden. Exceptions are imported stem cells dated before may 2007

In GB and Southcorea and USA is cloning allowed

Why to prefere studies on Why to prefere studies on adult stem cells?adult stem cells?

on one hand ES cells great hope for the progress in medicine on one hand ES cells great hope for the progress in medicine

on the other hand they are juridical and ethical problematicalon the other hand they are juridical and ethical problematical

adult stem cells are differen, there are no embryos requiredadult stem cells are differen, there are no embryos required

adult stem cells exist in nearly every organ – brain, skin, liver adult stem cells exist in nearly every organ – brain, skin, liver

although they are not that powerful than embryonic although they are not that powerful than embryonic stem stem cells they have great potential to heal diseases, as they cells they have great potential to heal diseases, as they can can transform to different blood cellstransform to different blood cells

Embryonic stem cell research and Embryonic stem cell research and religionreligion

Different religions view the status of the early human embryo Different religions view the status of the early human embryo in different ways: in different ways:

the Roman Catholic, Orthodox and conservative Protestant the Roman Catholic, Orthodox and conservative Protestant Churches believe the embryo has the status of a human from Churches believe the embryo has the status of a human from conceptionconception

no embryo research should be permitted no embryo research should be permitted

Judaism and Islam emphasize the importance of helping Judaism and Islam emphasize the importance of helping others and argue that the embryo does not have full human others and argue that the embryo does not have full human status before 40 days status before 40 days

permit some research on embryospermit some research on embryos

ConclusionConclusion

Athough most of ES cells were gained in the laboratory or by abortion and there would be destroyed anyway, life must be seen in the earliest stage and so be respected

Also cloning crosses the borders of human dignity and the respect of human life

research on adult stem cells is an acceptable alternative for studies on embryonic stem cells, these promising development in fields of medicine cannot withhold from mankind