FIGURE 25: Leukemia causes an alteration in the balance of each type of blood cell in the blood volume.
FIGURE 26: In a sample of blood from a leukemia patient, the sickle-blood cells appear in profuse quantities.
FIGURE 27: The defective blood cell may cause incredible damage to the organism.
(FIGURE 28)
BLOOD DISORDERS
LEUKEMIA
Leukemia is a type of cancer which targets the blood cells. Affecting millions of people diurnally, its previous treatments were not proven as effective as possible. With a growing emphasis on stem cell treatments in the medical field, leukemia patients have finally received another light. The devastating disease afflicts numerous people all around the world, from innocent children to the brave elderly. For every one hundred thousand people, 12.5 cases of leukemia are diagnosed. Fortunately, the survival over the past years have increased, weighing at 57 percent in 2007. Innovative treatments introduced by stem cell researchers have the potential of increasing the survival rate of leukemia patients, affecting millions of lives step by step.
Leukemia mainly affects lymphocytes, a type of white blood cells. There are two types of lymphocytes: lymphoid cells and myeloid cells.
Lymphoid cells are a vital aspect of the immune system of an organism. Developing from lymphoid stem cells, they differentiate into the various types of white blood cells, such as T cells and B cells. T cells aid the body in defending itself against various infections. One of their jobs, for example, is to provide the B cells with the information necessary to produce the correct antibody for the particular infection through a signal. The B cells, which are responsible for creation of antibodies, begin their work and release the correct antibodies necessary. The antibodies, in turn, bind to the antigens of the target and either impede a biological process that causes the illness or recruitment other cells, such as macrophages, for help in obliterating the intruder.
Myeloid cells are formed from the myeloid blast and are capable of maturing into a wider array of cells: red blood cells, platelets, and even certain types of white blood cells. Red blood cells contain a protein, hemoglobin, which transports oxygen through our body. Platelets, although make a small fraction of the blood cells, aid in blood clotting, a process essential for healing wounds. Since leukemia affects these processes, it results in death in 57% of its cases, most connected with immune system failure. Each case is different, however usually falls under one of the two established types of leukemia: acute or chronic.
1) Acute leukemia evolves rapidly, destroying the patient's immune system.
2)Chronic leukemia, on the other hand, progresses slowly since the affected cells retain some of their normal functions after the transformation, allowing the immune system to last longer, not destroying it quickly or completely.
ANEMIA: SICKLE-CELL
Like with most diseases, sickle-cell anemia is capable of targeting all members of our society. Luckily, stem cells are able to provide a cure for this disease, through the use of allogeneic hematopoietic stem cells.
WHAT IS SICKLE CELL ANEMIA?
- An inheritable disease, which must be passed down from BOTH parents.
- Red blood cells develop an uncharacteristic crescent, or sickle, shape.
- The abnormal blood cells are therefore, due to a different shape, are not able to carry a normal level of oxygen in the body
- Additionally, the sickle cells may interrupt blood flow, by either blocking smaller blood vessels or breaking into pieces.
STEM CELL TREATMENT
Currently, the stem cell therapy practiced for curing sickle-cell anemia is based upon the transplant of allogeneic hematopoietic stem cells. The steps to fulfill this treatment are as follows:
1. Isolate the adult stem cells from the patient’s bone marrow
2. Examine the stem cells for possible damage
3. Transform the adult stem cells into iPS cells
4. Correct the defective gene in the isolated stem cells
5. Stimulate the healthy stem cells to differentiate into immature red blood cells
6. Inject the new stem cells back into the patient’s blood stream
The protein affected by the genetic mutation is hemoglobin. Hemoglobin is the main protein responsible for the successful transportation of oxygen by red blood cells. When one inherits sickle-cell genes from both parents, then the
individual is afflicted with sickle-cell anemia. Abnormal blood cells clog vessels and damage normal blood flow. Stem cells extracted from the patient are treated to correct the defective gene, coding for normal hemoglobin protein. Then the altered adult stem cells, now iPS cells, are enabled to differentiate into red blood cells, and later returned to the patient’s blood stream.
Stem Cells in the News: Leukemia
A CANCER OF BLOOD CELLS
Leukemia is traditionally treated with bone marrow transplants. However, the high risk of immune rejection traces a path for stem cell therapy to enter. Stem cell therapy opens new opportunities of treatment of leukemia. Since this therapy will allow autologous transplants, this will cancel out the risk of immune rejection and the necessity of a bone marrow donor. Affected stem cells of the patient may be removed and stimulated to return to their normal state. Then, they may be cultured to increase in number and then injected back into the patient, after destroying the patient's cancerous bone marrow. The replacement will not cause an immune response, resulting in a healthy, cancer-free bone marrow!
Leukemia has transformed the lives of many, however its most deleterious and baneful consequences have been directed at and felt by the youngest members of our society - the immaculate and beatific children, whose lives have been tremendously metamorphosed in the process. One of the goals of stem cell researchers have been previously to develop a cure to save the lives of the patients, and now, the scientists work upon perfecting the techniques and improving the patients' post-cancerous states of lives.
STEM CELL TREATMENT
(Video 5)