ADULT VERSUS EMBRYONIC STEM CELLS
At the most basic level, the promise or presume-promise that stem cells hold is also the source of the controversy over them.
The idea that replacement parts/spare parts for our human bodies might one day be as easy to create as ordering prescription medication from the local drugstore is breathtaking(if one is still breathing by then). But if these same cells can only work their magic through the destruction of human embryos, then cure and curse will be one and the same to many people.
To those who see a human being's life as starting from the moment of fertilization, regenerative medicine via stem cells is nothing more than high-tech cannibalism.
Adult Stem Cells (ASCs) is an alternative, imperfect though it may be. Similar kinds of cells can be found outside the holy sphere of the human embryo's blastocyst. These "adult" stem cells can be found in the blood, the pockets of our bone marrow, the umbilical cord, under the dermis of the skin, and , just perhaps, buried deep in the brain.
Adult stem cells (ASCs) have their pros and cons. This technology of choice among those who morally object to the use of embryonic stem cells. Stem cells from bone marrow and umbilical cord blood are classic examples of ASCs.
"With the right policies and the right techniques, we can pursue scientific progress while still fulfilling our moral duties," said former US President Bush.
One question, but is this the case, or is it wishful thinking? As with many complex subjects, there is no clear-cut answer.
The right technique and right policy for mankind is just follow the nature law to exist, eat natural, drink natural water, breath natural fresh air along the nature park, grow and procreate naturally as we all know is right, without doubt.
The degree to which ASCs can be put to use often depends on who is being interviewed. However, if one sticks as closely as possible to what has been reliably reproduced in multiple laboratories over time, some hard facts do become available. That is, at least as "hard" as the facts can be, before the technology advances yet further and changes reality yet again.
Adult stem cells have something of a trade-off in their makeup. They simply do not have the pluripotent ability to morph into any kinds of cell. However, this one-track orientation allows them to be admirably well-suited building blocks for a limited nember of therapies. For example, blood-specific illnesses such as leukemia stand to benefit from the use of ADSs collected from bone marow !
A major limitation of ADCs that their boosters fail to mention is that being a full-grown cell, the biological markers of an individual have matured. This means that an ADC is more likely to cause a dangerous immune reaction if transplanted into another person. To avoid this, ADC transplants could only be carried out using a patient's own cells.
Until positive results are replicated in many other labs, it is difiicult to evaluate whether this can be done in a systematic way, today. Let's admit there is no hard answers yet.
The more conservative thing to say is that each human organ probably has a specific stem cell system behing it, and there probably isn't a lot of 'cross-talk' between them.
The research field is not as advanced as many outside the scientific community woulf think. the bottom line is that we haven't learned much from studying human stem cells. Most of what we know comes from studying mice, fish, and flies.
To that end, dult stem cells are harder to study in some ways. because they do not renew themselves indefinitely in thelab, as embryonic stem cells do, they must constantly be replenished if they are to be studied.
On the other hand, embryonic srem cells come with their own price tag in sweat and hard work, and scandals too. In order to keep renewing themselves indefinitely, constant feeding and attention must be performed, or the relatively fragile embryonic stem cells will either die off or twist themselves into a grotesque teratomatic growth in the petri dish.
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