Words you will meet in the guides

Coming from another person. In an allogeneic, or donor, transplant, the stem cells come from a relative or an unrelated volunteer whose cells are a close enough match to the patient's.

A protein made by the immune system that sticks to one specific target, such as a germ. Some wrongly target the body's own tissues. Lab-made antibody medicines can target markers such as CD20 or CD38 on some cancer cells.

Coming from the patient's own body. In an autologous transplant, the patient's own stem cells are collected and stored, then given back after high-dose treatment. It does not use a donor.

A type of white blood cell that makes antibodies. B cells are part of the immune system and grow from stem cells in the bone marrow. Some lymphomas and leukemias start in B cells.

Young blood cells that have not finished developing. In leukemia and some related diseases, abnormal blasts build up in the marrow and blood and leave less room for healthy blood cells. Doctors count blasts to help identify the disease.

Young cells that can grow into every type of blood cell: red cells that carry oxygen, white cells that fight infection and platelets that help blood clot. They are found in the bone marrow and the bloodstream.

The soft, spongy tissue in the center of most bones. Red bone marrow holds the blood-forming stem cells that make red blood cells, white blood cells and platelets.

A treatment that takes a patient's own T cells, changes them in a lab so they can find and attack cancer cells, then gives them back through a vein. Standard CAR-T therapy does not use a donor.

A research study that tests how well a new medical approach works in people. Trials can test new ways to screen for, prevent, diagnose or treat a disease.

Treatment that prepares a patient for a stem cell transplant. It can include chemotherapy, radiation or antibody medicines. It makes room in the marrow for the new cells, helps prevent rejection and can kill cancer cells.

Blood collected from a newborn baby's umbilical cord after birth. It contains many blood-forming stem cells, so donated cord blood can be used for a stem cell transplant.

Treatment that adds a new gene or restores the work of a faulty or missing one. For some inherited disorders, the patient's own blood-forming stem cells are changed in a lab and given back. It does not use a donor.

The blood-forming stem cells given to a patient in a transplant. In a donor transplant, the graft comes from the donor's bone marrow or blood, or from donated cord blood.

A complication of a donor transplant. The donated cells see the patient's healthy tissues as foreign and attack them, especially the skin, liver and gut. It can start soon after transplant or much later and can be life-threatening.

Very strong drug treatment given in large doses, often to kill cancer cells. It also destroys the bone marrow and can cause other serious side effects. A stem cell transplant usually follows to rebuild the marrow.

Markers on most cells that make up a person's tissue type. Doctors test a patient's and donor's HLA to see how well they match. The more markers they share, the better the chance the body accepts the donor's cells.

Treatment that lowers the activity of the immune system. It can calm an immune attack on the body, as in aplastic anemia, or help keep the body from rejecting a transplant. It also makes infections harder to fight.

A group of cancers in which the bone marrow does not make enough healthy blood cells and abnormal cells appear in the blood or marrow. Also called myelodysplastic syndromes (MDS). Sometimes they turn into acute myeloid leukemia.

Having to do with the bone marrow, or with certain blood-forming cells made there. Also called myelogenous. Acute myeloid leukemia (AML) is a fast-growing cancer that starts in these cells.

A type of white blood cell that is one of the first to respond to germs such as bacteria. Low neutrophil levels raise the risk of serious infection.

Blood that flows through the body. For transplants, stem cells can be collected from this blood instead of the bone marrow. A medicine first moves stem cells from the marrow into the blood; then a machine collects them.

Tiny pieces of cells in the blood that help form clots to slow or stop bleeding. They are made in the bone marrow. Too few platelets can cause easy bruising and bleeding.

Describes a disease that does not respond to treatment. It may resist treatment from the start, or treatment may stop working along the way.

When a disease comes back after a period of getting better. Relapsed disease has returned after treatment helped for a time.

A decrease in or disappearance of the signs of a disease. In complete remission, no signs can be found, but some disease cells may still be in the body.

A treatment that gives a patient healthy blood-forming stem cells through a vein. The cells travel to the bone marrow and replace faulty marrow or marrow damaged by treatment. They can come from the patient or a donor.

Affecting the whole body. Systemic treatment uses medicines that travel through the blood to reach cells all over the body.

A type of white blood cell that is part of the immune system. T cells grow from stem cells in the bone marrow, help protect the body from infection and may help fight cancer.

Medicines designed to act on specific molecules involved in a disease. In cancer, they target molecules that cancer cells need to survive and spread. Some block signals that tell cancer cells to grow; others help the immune system kill them.

Putting blood, or parts of blood such as red cells or platelets, into a person's bloodstream through a vein. Some people with blood disorders need regular transfusions.