STEM CELLS BONE FRACTURE

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1 BIOLOGY UNIT 2 MRS. CATHERINE JACKSON STEM CELLS BONE FRACTURE By AYESHA SYED 10C

2 2 Stem Cell (Introduction) Stem cells are undifferentiated cells that have not yet become a specialised cell, with a specific task. These cells have the potential to turn into many different types of specialised cells. Thus, scientists believe that they have the ability to replace damaged cells in the body because some cells are unable to be fixed on their own, causing a great amount of damage. One source of stem cells is the embryo of which a baby is later formed. Due to this, stem cells have many ethical concerns and considerations around the topic. The fusion of two gametes become the starting point of all multicellular organisms. The zygote that is formed when the sperm and ova meet contains all the necessary genetic information required to make a fully functioning organism. The zygote undergoes mitosis and new cells are formed. These cells are called totipotent stem cells and have the ability to become any type of cell. Totipotent cells are the most versatile of stem cells, during the early cells divisions many totipotent cells are produced. After approximately 4 days the totipotent cells begin to slowly specialise and make a cluster known as a blastocyst. As seen in the diagram to the right, one can see that within the blastocyst there is another cluster cells. These inner pluripotent stem cell mass is what will later go on to become many of the cells and tissues in the body. A pluripotent cells cannot give rise to a placenta or any other tissues that are involved with foetal development, but can develop into internal body cells (nerve, heart, muscle and blood cells). It is pluripotent stem cells that scientist believe have the potential for the treatment of many diseases.

3 3 There are some challenges that are relate to the pluripotent stem cell, scientists are trying to discover ways of controlling the development process of these stem cells so that they can be cultured into desired human body cells. A second challenge faced by researchers is that the cells are commonly rejected by the person s body because of the immune system. Multipotent cells are the next type of stem cells. These stem cells are not found in the embryo and are rather found in the tissue adult mammals. It can estimated that multipotent cells are found in most of the body s organs, they replace the old and dead cells. The main function of these cells is to replenish the cells in one's body. A multipotent cell can become many types of cells but it still quite limited in its ability to differentiate. An example is the multipotent stem cells in the brain that can become different types of neural, glia or haematopoietic cells but still cannot create brain cells. Commented [1]: Excellent introduction Bone Fracture A bone fracture or a broken bone is a result of when an extreme amount of force is placed upon a bone, this force is far too great for the joint to bear. This causes a shift in the structure and strength of the bone. A bone fracture is majorly diagnosed via a x-ray. Symptoms: Bruising Pain and Swelling Unusual bending of the limb or area, Inability to move or place weight on the injured area. According to the Huffington Post there are 7 types of bone fractures: Bowing Fracture: The bone is bent, but not broken (only occurs in children) Hairline Fracture: A small, thin break in the bone. Greenstick Fracture: The bone is cracked only on one side. Single Fracture: The bone is only broken in one place. Simple Fracture: The bone is broken into two pieces. Comminuted Fracture: The bone is broken in more than places. two Commented [2]: Try and use a scientific reference

4 4 Open Fracture: The broken bone is sticking out through the skin. Bones are a form of connective tissue made stronger with calcium and bone cells. In the centre of bones lie a soft area known as the marrow, this is the place where blood cells are made. The main function of one's skeletal make up is to support the body and to provide protection for our internal organs. There are a variety of bone fractures, each depending on the amount of strength of the force. The most common areas where fractures take place are the wrist, ankle and hip. However, hip fractures tend to mainly occur among the elderly as their bones become slightly brittle with age. When given the correct treatment bone fractures take approximately 8 weeks to heal. How does a break impact our body? A person who has a major bone injury will most likely feel dizzy, and cold due to their body going into shock. After a few hours of the bone breaking a clot has formed around the break, white blood cells attempt to get rid of germs that may have entered the body. Much further into the recovery process, cells called chondroblasts form as soft collagen callus around the break. The soft callus eventually transforms into a hard callus, thus creating a new bone. The final stage of healing is the natural breaking down of the remain, not needed bone. A severe bone fracture will cause extreme nerve damage which leads to circulation problems and numbness. If a bone fracture is left without treatment then the following can occur: - Bone deformity - Permanent nerve damage - Extended pain and swelling An untreated bone injury can have have a huge impact on the patient's life as the bone will begin to heal in an incorrect position, leading to a deformed limb and extreme pain in the future. The patient will be unable to complete basic tasks, if the injury such as an open fracture

5 5 then infection and severe blood loss will occur. In worst case scenarios death may occur as a result from extreme blood loss. How can stem cells assist? Stem cells have been used for years in successfully treating bone fractures, that would otherwise not have healed as easily. The stem cells are applied directly to the site of wound, they promote new bone growth, fill gaps and allow healing and assist in the restoration of function. The obtaining of the stem cells has proved to be problematic for patients as the cells come from a patient s own bone marrow(erases the need for embryonic stem cells). It requires the cells to be retrieved during an extremely painful surgical procedure that involved a basic general anesthesia and a large needle being put into the hip. Postoperative recovery is usually a week. The cells must be isolated from the bone marrow before being transplanted back into the patient thus the process is so long that another surgery is required. The cells are destined to become healing blood vessels. Another source of stem cells is currently being examined. Stem cells from fat is becoming a point of interest among researchers. Promoting cells from a person s fat to regenerate a damaged bone, has high expectations of better form and function. A study is currently being funded by the United States Army to look into how stem cells from fat can repair damaged bones, in hope of military help and assistance to the general public.

6 6 The method that has been determined so far involves the use of a material with a gel-like consistency. This material then encourages stem cells, which are multipotent, to repair the bone that has been damaged. The stem cells activate the body s healing system. They aim to stimulate the growth of tiny blood vessels that are found within bone that is just in the developing stages. Thus, the bone is essentially healing itself with the assistance of the multipotent stem cells. The gel used in the procedure contain the stem cells to the site. As the bone begins to gradually heal the gel then dissolves away as it is no longer required. An attempt to use these fat sourced stem cells has already been made by scientists but it was failed because the stem cells did not stay contained to the required area and moved around the entire body. However, the above mentioned gel fixes this problem. The initial trial of this procedure was done on a horse, when a veterinary professor used the injection approach on a race horse that had already been receiving treatment for bone cysts. The stem cells were injected with no gel, but an attempt has been made to use the gel in three more horses. Advantages of using stem cells from one s own fat: - Less chance of rejection because the body will recognise the cells as being its own. - Fat is conveniently more accessible - Less painful - Not as time-consuming - Large number of cells can be isolated at once. Drawbacks from this The stem cells that are in discussion are adult stem cells that are not related to the controversial global discussion of embryonic stem cells. In fact, the catholic church and the southern baptist Church have passed papers in favour of the research into adult stem cells. It has been deemed ethically acceptable alternative to the otherwise controversial part. One minor setback in regards to the use of the discussed adult stem cells is that the treatment takes more that one week. It is absolutely essential that the stem cells do not move around the body and are in a stable position throughout the recovery plan.

7 7 One week is required to rest after the mini-liposuction, and 5 days to test the adipose cell samples for aerobic and anaerobic bacteria. This is done to ensure that no infected sample is released. Another 5 days must pass before the cells can be deemed safe and then injected back into the patient. After the transplant of the cells into the patient s body, another 5 days are allocated to ensuring that the stem cells are responding to the body. Side Effects: - Initial pain on injection site - Minor Fever - Headache - Nausea or vomiting However, these side effects tend only last about 24 hrs, no long term side effects have been recorded. External Research Links: 1) McMacken, M. (2017). Stem Cell Research at Johns Hopkins Medicine: Joint Repair. Hopkinsmedicine.org. Retrieved 22 August 2017, from Team Leader: Prof. Jennifer Elisseeff Ph.D (associate professor of biomedical engineering ai the Johns Hopkins University School of Medicine) Statement of understanding: Biomedical engineers at the Johns Hopkins Medical stem research department have come up with an idea of using stem cells from adult goats into a tissue that resembles a cartilage. If successful, this procedure will become a minimally invasive way of repairing injured knees, noses and many other bone and cartilage injuries. A fluid filled with stem cells and nutrients is injected into the damaged tissue, light is then used to harden the fluid into a hardened gel of some sorts. The stem cells them have the ability is multiple and form new bone to replenish the damaged body part. 2) UQ researchers make breakthrough in stem cell research. (1329). Centre for Clinical Research. Retrieved 22 August 2017, from

8 8 research.centre.uq.edu.au/article/2016/12/uq-researchers-make-breakthrough-stem-cellresearch Team Leader: Professor Nicholas Fisk (UQ Clinical Research Centre) The University of Queensland scientists have conducted research on a unique method of making mesenchymal stem cells. These stem cells are used to repair bone and many other organs. A small molecule is used to induce embryonic stem cells over a 10 day duration, in comparison to other studies being done around the world, this way is much faster. Instead of using the safer option of using fat stem cells, this clinical research task is looking at the use of embryonic stem cells. Commented [3]: 2 great examples of research