Adult Stem Cells From Bone Marrow example essay topic

Few scientific issues in recent years have managed to draw as much attention, both scientific and otherwise, than stem cell research. I was first introduced to the term 'stem cells' when I was in high school, and since then, I have had a keen interest in the direction science is taking them. When considering medical research as a whole, stem cells appear to have the makings of a 21st century medical revolution a la discovery of antibiotics. The open-ended nature of stems cells has been recognized by many in the community who see these cells as the golden key for curing and ameliorating many degenerative diseases such as diabetes, Parkinson's, and heart disease, as well as accidental damage such as a spinal cord injury.

Clearly, stem cells hold a great deal of promise in medical research and I feel that being more than casually aware of something that will greatly affect health care and my future studies if I chose to pursue medical research in graduate school, is critical. Unfortunately, having not had the occasion to do my own research on the subject, I feel this assignment presents the perfect opportunity (and encouragement) to explore the area. First isolated in 1998, stem cells are the body's clay, having the potential to become any type of cell. Stem cells are divided into two classes - adult and embryonic. Adult stem cells are found among already differentiated cells of specific tissue and can usually only become one certain type of cell (blood, marrow, liver etc.) Embryonic stem cells are cultured cells obtained from the inner part of a blastocyst - a very early embryo that has divided into about 100 cells. This type of stem cells is particularly controversial because the cells must be extracted from an embryo.

However, to do this the embryo must be destroyed, a process which some believe is tantamount to taking human life. Nonetheless, embryonic stem cells have a number of remarkable properties, properties which make them very desirable for use in medicinal research. For instance, stem cells can be grown infinitely. Unlike other permanent cell lines which are apt to mutate in later passages, embryonic stem cells remain 'normal' regardless of how long the cell line has been carried out.

They also have the ability, under the right conditions, to give rise to all cell types of the body. Despite these advantageous properties, there is one glaring problem that remains in the usage of embryonic cells and that is the body's immune response of rejection. The few stem cell lines that have been established are simply not a viable solution for the entire population. One way to remedy this problem would be through the establishment of a bank that contained hundreds of cell lines. This would increase the chance of a patient finding a match and thus decreasing the chance of an unfavorable immune response. However, the current administration has shown a continued unwillingness to increase our stem cell bank, a move which might prove to be less than smart for a country trying to remain at the forefront of medicinal research.

An apparently convenient solution to this dilemma appeared not long ago in the form of a sheep. In 1997, a lab Edinburgh, Scotland developed a technique which showed that it was indeed possible to reprogram the nucleus of an adult cell. Their novel approach was based on the following: A unfertilized egg contains a large amount of jelly-like material known as the cytoplasm which contains factors that under normal circumstances reprogram the incoming sperm nucleus such that an embryo is formed. However, these factors are also capable of reprogramming an adult cell's nucleus that can be injected into the egg. By removing the egg's own nucleus and replacing it with one from an adult cell, it is possible for this hybrid cell to become an embryo.

This greatest benefit from this technique is that because the egg is never fertilized, scientists are able to take advantage of these embryonic stem cells without having to worry about ethical issues. There are, however, other options available that avoid completely the scarlet letter which of embryonic cells. Rather than using stem cells from an embryo - which is both controversial and difficult due to the lack cell lines - scientists have found promise in adult stem cells. Research has determined that adult stem cells found in the body have the potential to differentiate into different types of cells. Researchers at the Louisiana State University tested adult stem cells from bone marrow to provide a therapy for Cystic Fibrosis. They discovered that, if put into the right environment, stem cells from bone marrow could differentiate into airway epithelial - the tissue in the lung that is damaged by Cystic Fibrosis.

It is normally very difficult and tedious to isolate adult stem cells within the tissue due to the fact that there is simply not many of them to be found. However, the group at Louisiana made a significant advance in adult-cell separation with the development of their air-liquid-interface co culture method for isolating the stem cells from the bone marrow. This method could facilitate the exploration of bone marrow stem cells for therapy of different lung diseases. However, there are some disadvantages from using these adult stem cells. As stated above, they are often rare and inaccessible. Blood stem cells are present in very low numbers in blood, about one in ten million.

Although they are more frequently found in in bone marrow, they are still rare, and further the removal of bone marrow itself is a fairly risky operation. Also, they do not live as long in a culture as embryonic cells and moreover are genetically unstable in that the cells may carry genetic mutations for disease or become defective during experimentation. For years, researchers have assumed that development is a one-street in that a cell that starts on the path towards becomes a certain type of cell will always in fact become that certain cell type. However, studies in the past few years have suggested that adult cells might indeed be able to turn back and take another path if the body is in need of another cell type. However, some biologists have been skeptical about these claims.

Two groups, working independently of each other, both reported that cells from adult tissue can fuse with embryonic cells in a culture, producing a hybrid that looks like a reprogrammed adult cell but has the characteristics of the embryonic cell. The hybrid cells also show chromosomal abnormalities such as having twice as many chromosomes as normal; suggesting that it might not be prudent to replace an already damaged tissue with those particular cells. Nonetheless, these doubts have not weakened the scientific community's effort to continue researching potential treatments for diseases. Tone particular prevalent, and perhaps treatable disease, is diabetes. The prevalence of diabetes in the world population is increasing at an alarming rate and it is estimated that in 2003, there were 191 million people with diabetes and it is predicted that by 2025, there will be 334 million people. (web). Unfortunately, there is currently no cure for diabetes.

However, it may be that stem cells, from either an embryo or the pancreas, can provide this cure. Exploiting these cells for therapy, rather than using something such as synthetic insulin, is a significant change as it means moving away from the more traditional chemical approaches used for treatment of diseases. There is a large amount of evidence that indicates stem cells that produce islets (that is, cells which produce insulin) exist in the pancreas. However, they also exist in the bone marrow, liver, and umbilical cord blood. These cells can be isolated in vito and be induced to differentiate into insulin-producing islet-like clusters. The problem encountered with this tactic is that each of the cells was placed in contact with powerful growth factors (fetal serum, basic fibroblast growth factor, epidermal growth factor, and nerve growth factor) by virtue of being grown in vito.

These manufactured conditions, which are obviously not be present in viv o, greatly affected the differentiation pathway of the cells, making this an unfeasible solution for the moment. The research for human stem cells is in its infancy. However, clearly there exists concerns regarding the morality of stem cell usage - - the matter being no longer can we harvest and use stem cells, but should we. Every country, and ultimately every individual will be forced to decide for themselves how they feel about the moral aspects of the use of these technologies.

However, demands by individuals and countries blanket ly forbidding this type of research before it is fully understood is short-sighted. It seems only logical that we would want to know exactly what we are giving, before we give it up.