Alyssa Jasper by linzhengnd


									Alyssa Jasper

January 14, 2011

Chemistry II H

Final Project

            Biotechnology: Tissue Engineering- Recreating Organs With Stem Cells

       Biotechnology is a broad multifaceted subject yet is most often described as applied

biology. The term "biotechnology" refers to the use of living organisms or their products to

modify human health and the environment. Humans have developed different techniques within

biotechnology since prehistoric times. Biotechnology can be used as a process of growing food

and developing agriculture, and in the discovery of new medicines and vaccines.

       Biotechnology is greatly improved human relationships and connection to food and

agriculture. Biotechnology originated in the production of food thousands of years ago, and is

widely used in the process of making food. For example, fruit juices can be fermented into wine,

milk can be converted into cheese or yogurt, and beer can be made by fermenting solutions of

malt. The first bakers found that they could make a soft, spongy bread rather than a firm, thin

cracker by using yeast in the process of fermentation.

       Another area that has been vastly affected by biotechnology is cellular biology. Through

biotechnology, a better understanding of organisms and their cellular functions has been formed.

This information allows scientists and researchers to gain control of, and alter many functions

performed by cells and organisms. Techniques, such as gene splicing and recombinant DNA

technology, allows us to control the genetic elements by taking functioning lengths of DNA from

one organism and placing it into the cells of another organism. As a result cells can be used to
produce useful human molecules. Cows can produce more milk for the same amount of food,

and we can synthesize therapeutic molecules that have never before existed.

       Medicine is yet another place where you can use biotechnology. Biotechnology in

medicine began when scientists synthetically produced biologically made antibiotics. Alexander

Fleming discovered penicillin in 1929 and it is considered a paradigm for biotechnology.

Biotechnology is also being used in vaccines. Scientists are trying to integrate vaccines in regular

foods such as bananas in order to make the application of vaccines easier. People are more likely

to take the vaccine if it is in a banana rather than the needle itself. Other uses of biotechnology

in modern medicine includes drug production, determining genetic origins or disease, producing

organs for transplant, and developing other diagnostic methods.

       Biotechnology has improved not only the quality of life but has greatly impacted society;

however, like everything else in the world, biotechnology has its advantages and disadvantages.

The test and information that can be learned using biotechnology is amazing. Main

disadvantages come in the form of ethical dilemmas. Long term ecological and biological effects

are unknown. Many critics ask when “enough is enough.” We alter bacterial DNA, and then

plant DNA, etc; will we (humans) know when to stop? and would it be okay to alter human


                                                        Figure 1. The uses of stem cells within the

                                                human body & society. Stem cells have multiple

                                                application areas from making bone marrow to

                                                being used in biopharmaceuticals.
       Stem cells play a large role in biotechnology. A stem cell starts out as a cell in the body

that does not yet have a purpose or a specific differentiation function. In other words a red blood

cell has a job; it was designed by the body to carry oxygen from the lungs to tissues and

removing CO2. Its only function is to be a red blood cell it will never be able to be a heart cell

etc. Stem cells are the body’s raw materials. They make all other cells with specialized functions.

Under the right conditions, stem cells can undergo meiosis and divide into two cells, called

daughter cells. When there are two daughter cells present, two things can happen: differentiation

and self renewal. Self renewal means that new stem cells form while differentiation means that

specialized cells can form such as blood cells, brain cells, and heart muscle or bone. Stem cells

are the only cells in the body that can create new cell types.

                                                                                          Figure 2.

                                                                          Hierarchy of Stem Cells.

                                                                          Stem cells break down

                                                                          into smaller and smaller

                                                                          things such as nerve and

                                                                          bone cells.

                                                                                  By maintaining a

                                                                          constant watch and

                                                                          monitoring the bones,

                                                                          muscles, and cells,

doctors will be able to discover how the diseases and conditions develop. Stem cells will be a

great benefit to the medical and public health fields due to the fact that they can generate healthy
cells to take the place of the diseased ones. This field of study is called regenerative medicine.

Researchers are hoping that this field will grow, so that in time, they will be able to regenerate

damaged tissue as well as damaged cells. Stem cell therapies benefit those with Type 1 Diabetes,

spinal injuries, Parkinson's disease, Alzheimer's disease, heart disease, stroke, rheumatoid

arthritis, osteoarthritis and multiple sclerosis.

        A future avenue of stem cell research is the use of stem cells to recreate organs. Scientists

have already begun to use stem cells to recreate tissues and bone muscles. Recreating organs will

help people with diseases and those who need transplants.

        One situation in which this technology was use was on Claudia Castillo, a thirty year old

mother of two, who had her damaged windpipe replaced. The stem cells were grown in a lab at

Bristol University, England. The new windpipe was made from cells that were taken from her

own body. This process is called “tissue engineering.” The cells came from her body so she did

not have to take powerful drugs to stop her body from rejecting the organ. By avoiding these

drugs, Claudia won’t be at an increased risk of developing cancer like other transplant patients,

which is another significant advantage of tissue engineering (N. Graham)

        Another situation where tissue engineering took place was with Geoffrey Gutner. He said

that “tissue engineering” has failed miserably many times due to the lack of blood vessels there

are to do testing with. The key to stem cells is to keep them adequately supplied with oxygen and

nutrients while they are outside the body.

        Bob Beale, an editor from ABC Science online, reports in one of his articles, a story

about a research team led by Dr. Shulamit Levenberg. Levenberg and his team have taken a step

closer to growing living organs for transplant. Their research shows that the human embryonic

stem cells can be encouraged to grow on scaffolds into three-dimensional structures, like an
organ. When the cells were then stimulated, they differentiated into more complex structures.

These structures closely resembled characteristics of developing nerve tissue, cartilage, or the

liver. Researchers then took these structures and transplanted them into lab mice. They found

that they continue to express proteins and then also began to integrate with their hosts’ blood

supply. Although this is research is far from making an organ they are definitely taking a step in

the right direction where maybe eventually this research could turn into a pancreas or a liver


                                                                 Figure 3. A visual representation

                                                         of tissue engineering. [expand]

                                                                 Martin Korbling, M.D. says,

                                                         “These cells are capable of maintaining,

                                                         generating, and replacing terminally

                                                         differentiated cells within their own

                                                         specific tissue as a consequence of

                                                         physiologic cell turnover or tissue

                                                         damage due to injury. Hematopoietic

                                                         stem cells that give rise to blood cells

                                                         and move between bone marrow and

peripheral blood are the best-characterized adult stem cells in humans (M.Korbling). Recent

data suggest that adult stem cells generate differentiated cells beyond their own tissue

boundaries, a process termed “developmental plasticity.”

        As stated before the ethical perspective of society is often something that may put a

process or field of study on hold. Stem cell therapy and the recreation of organs with stem cells
is a very controversial issue, and many parts of the research have been put on hold. As a

scientist, you often have to make sure that you have society on your side because you don’t want

them to rule your experiment or research unethical. Many of the members of society rule science

and technology as unethical but often lack the education/ knowledge on the topic and tend to

regurgitate information given by religious or political leaders instead of finding the truth. A

major misconception with the public forum is that stem cells are only available from fetus and

they must be aborted in order to harvest them. This is preposterous!

        There is a lot in store for the future of stem cell research and I am very interested to see

what happens in the next generation.
                                           Works Cited

Abraham, C. (2008, August 18). Scientists a step closer to creating replacement organs .
      Retrieved from

Andrews, W. (2008, March 23). Medicine's cutting edge: re-growing organs. Retrieved from 219

Beale, B. (2003). Beale, b. (2003, october 14). stem cells used to create new organ tissue.
       retrieved from News in
       Science, Retrieved from

Graham, N. (2008). Organs grown from stem cells in lab successfully transplanted in.The
      Huffington Post, Retrieved from
      grown-from-stem cel_n_145049.html

Genetic Science Learning Center (2010, October 8) Stem Cell Therapies Today.
       Learn.Genetics. Retrieved November 19, 2010, from

Korbling, M. (2003). Adult stem cells for tissue repair — a new therapeutic concept?.The \
       New England Journal of Medicine, Retrieved from

Lee, F. (2009). Creating organs from our own stem cells. HealthCare Hacks, Retrieved from stem-cells

Moore, S. (1967). Stem-cell migration in developing myeloid and lymphoid systems . The
      Lancet, 290(1517), Retrieved from\ =B6T1B497SNDN
      96c71087697386cf941524815b13&search ype=a

Stanford University Medical Center (2009, March 2). From Stem Cells To New Organs:
       Scientists Cross Threshold In Regenerative

Watson, S. (2010). How stem cells work. How Stuff Works, Retrieved from

To top