Journal of Cancer Research and Immuno-Oncology
Open Access

Leukaemia

Blood cells are formed in the bone marrow, the spongy tissue found inside the bones. Blood-forming stem cells divide to produce either more stem cells or immature cells that become mature blood cells over time. A blood stem cell may become a myeloid stem cell or a lymphoid stem cell.

A myeloid stem cell becomes one of three types of mature blood cells:

Red blood cells that carry oxygen to all tissues of the body. Platelets that form blood clots to stop bleeding. Granulocytes (white blood cells) that fight infection and disease.

A lymphoid stem cell becomes a lymphoblast cell and then one of three types of lymphocytes (white blood cells):

B lymphocytes that make antibodies to help fight infection. T lymphocytes that help B lymphocytes make the antibodies that help fight infection. Natural killer cells that attack cancer cells and viruses.

Leukaemia affects white blood cells and can be classified by the type of white cell affected (myeloid or lymphatic) and by the way the disease progresses (acute or chronic). Acute and chronic do not refer to how serious the disease is but to how rapidly it progresses.