Hematopoietic stem cells can turn into three types of blood cells, all of which have important functions that help keep a person alive and healthy. The three types of blood cells formed from the stem cells within red bone marrow are:. The second type of bone marrow found in the body is yellow bone marrow, which gets its name from its high concentration of fat cells, which appear yellow in color. This type of bone marrow can be found in the medullary cavity in the shaft of long bones and is often surrounded by a layer of red bone marrow.
Yellow bone marrow contains mesenchymal stem cells marrow stromal cells , which produce cartilage, fat and bone. Yellow bone marrow also aids in the storage of fats in cells called adipocytes. This helps maintain the right environment and provides the sustenance that bones need to function. As previously discussed, the function of bone marrow is to produce different types of cells that are vital to sustaining life. A number of circumstances can affect the health of bone marrow and impair its ability to produce a normal amount of healthy cells.
A bone marrow transplant, in which healthy bone marrow is administered to a patient via a central line, may be necessary in these instances. A bone marrow transplant can help to:. Bone marrow stays red until the age of seven. As we age, about half of red bone marrow is slowly replaced by yellow bone marrow.
Adults have an average of 5. Yellow bone marrow is located in the hollow cavity of long bones. It is typically found at the center surrounded by red bone marrow. Red bone marrow can be found in the cavities of long bones, but is also found in the shoulder blades, hips, skull and flat bones.
There are many things you can do to take care of your bones. Healthy bone marrow and blood cells are necessary to live. Some people are affected by diseases that cause the bone marrow to function improperly and no longer produce healthy blood cells. Testing is necessary to diagnose conditions that affect the bone marrow, such as blood cancers like leukemia and lymphoma, or sickle cell anemia.
About 10, people in the U. Testing can include aspiration. A hollow needle is inserted into the hip to remove about one milliliter of liquid bone marrow to be examined via microscope.
A biopsy uses a larger needle to remove a solid core of bone tissue for examinations. Because of the danger of this complication, autologous transplants are more common.
Past studies suggest that people aged over 50 years have a higher risk of complications following bone marrow transplantation. For this reason, experts have typically advised against undergoing transplantation after this age. However, advances in medical technology have reduced these risks. The authors of a report conclude that transplantation can be safe for people aged over 70 years, if they meet certain criteria.
There is little risk to those who donate because they generate new bone marrow to replace removed bone marrow. There is, however, a slight risk of infection, and a reaction to anesthetics can occur with any surgical procedure. As bone marrow affects many bodily systems, a problem can result in a wide range of conditions, including cancers that affect the blood.
A number of conditions pose a threat to bone marrow because they prevent it from turning stem cells into essential cells. A bone marrow examination can help diagnose:. About every 3 minutes in the United States, someone receives a diagnosis of blood cancer. A bone marrow transplant is often the best chance for survival. Bone marrow transplants are sometimes necessary after certain treatments, such as high dose chemotherapy and radiation therapy, that treat cancer.
These treatments tend to damage healthy stem cells as well as destroy cancer cells. Bone marrow tests can help diagnose certain conditions, especially those related to blood and blood-forming organs. Testing provides information on iron stores and blood production. Bone marrow aspiration uses a hollow needle to remove a small sample about 1 ml of bone marrow for examination under a microscope. A healthcare professional usually inserts a needle into the hip or sternum in adults or into the upper part of the tibia the larger bone of the lower leg in children.
They use suction to extract the sample. They typically perform bone marrow aspiration when previous blood tests have indicated a need for it.
It is particularly useful in providing information on various stages of immature blood cells. The second method, which is more common, is peripheral blood stem cell PBSC donation. This involves filtering stem cells directly from the blood. It is these blood stem cells, rather than bone marrow itself, that are necessary for the treatment of blood cancers and other conditions.
When an individual joins a bone marrow donation registry, they are agreeing to donate using whichever method the healthcare professional deems appropriate. Donors never pay for donating, and they are never paid to donate. The risk to a donor is minimal.
Over With blood marrow donation, the major risk involves the use of anesthetics during the procedure. With PBSC donation, the procedure itself — which involves filtering blood through a machine — is not dangerous.
The NMDP has links with registries around the world, but there is an urgent need for more donors. The following are some general guidelines for bone marrow donation as recommended by the NMDP. The guidelines aim to protect the health and safety of both the donor and the recipient.
Donors should contact their local NMDP center for specific details and to discuss donations with a healthcare team. Antianxiety and antidepressant drugs are allowed as long as the condition is under control. People with Lyme disease , malaria , or recent tattoos or piercings should wait at least a year before donating bone marrow. After registering to donate, the person undergoes an HLA-typing test, which healthcare professionals use to match individuals with potential donors.
The healthcare professional then adds their HLA type to a database of potential donors, and they search the registry to try to find a match. They compare proteins in the blood cells to see if they are similar to those of the recipient.
They then contact the potential donor if there is a match. About Before a person can donate PBSC, they need to undergo daily injections of a medication called filgrastim in the 5 days leading up to the procedure. This medication draws stem cells from the bone marrow, so the donor has more of them circulating in their blood. Donating PBSC involves a procedure known as apheresis. This is when a healthcare professional takes blood from the body using a catheter inserted into one arm.
The blood passes through a machine, which filters out the stem cells, along with platelets and white blood cells. The remaining blood, which consists mainly of plasma and red blood cells, flows back into the body through a vein in the other arm. The procedure is completely painless and is similar to donating plasma. Most PBSC donations can take place in one apheresis session that may take up to 8 hours.
The filgrastim injections before donation may cause the following effects for several days :. If a person is donating bone marrow instead of PBSC, there is no need for filgrastim injections. Bone marrow donation is a surgical procedure that takes place in the operating room.
It requires anesthetics and is, therefore, completely painless. The entire procedure takes 1—2 hours. In a small number of cases, they receive local anesthetics, which numb the area that the healthcare professional takes bone marrow from. In this situation, the donor is awake throughout the procedure. The person lies on their stomach. A healthcare professional makes an incision about a quarter of an inch in length on both sides of the pelvic bone.
They then insert special, hollow needles into the bone, through which they draw the liquid marrow. The incisions do not usually require stitches. After the procedure, the donor stays in a recovery room until they regain consciousness.
Once they can eat, drink, and walk, they can leave. After bone marrow donation, the average recovery time is 20 days. Bone marrow replaces itself within 4—6 weeks.
These effects may persist for a few days to several weeks. A person who donates PBSC is unlikely to experience any side effects following the donation, other than bruising at the needle site.
Recovery time is almost immediate. A person whose condition is stable or in remission has a better chance of a good outcome than someone who has a transplant in a later stage or with relapsed disease. Young age at the time of transplant also improves the chance of success. Transplants for nonmalignant conditions tend to have more favorable outcomes.
A bone marrow transplant BMT restores healthy bone marrow in children with stem cell defects, cancer and certain inherited diseases. Get more info. Bone marrow donors may be relatives including siblings or unrelated volunteers. Find out what happens before, during and after bone marrow donation.
Aplastic anemia. Ewing's sarcoma. Hodgkin's lymphoma. Non-Hodgkin's lymphoma. Sickle cell disease. Patient Education A-Z.
0コメント