WASHINGTON, Dec. 25 (Xinhua) -- A University of Michigan lab has created artificial bone marrow that can continuously make red and white blood cells.

    This development could lead to simpler pharmaceutical drug testing, closer study of immune system defects and a continuous supply of blood for transfusions, the research team reported in the current issue of journal Biomaterials.

    The substance grows on a 3-D scaffold that mimics the tissues supporting bone marrow in the body, said Nicholas Kotov, the lead researcher.

    The marrow is not made to be implanted in the body, like most 3-D biomedical scaffolds. It is designed to function in a test tube.

    "This is the first successful artificial bone marrow," Kotov said. "It has two of the essential functions of bone marrow. It can replicate blood stem cells and produce B cells. The latter are the key immune cells producing antibodies that are important to fighting many diseases."

    To determine whether the substance behaves like real bone marrow, the scientists implanted it in mice with immune deficiencies. The mice produced human immune cells and blood vessels grew through the substance.

    Blood stem cells give rise to blood as well as several other types of cells. B cells, a type of white blood cell, battle colds, bacterial infections, and other foreign or abnormal cells including some cancers.

    Cancer-fighting chemotherapy drugs can strongly suppress bone marrow function, leaving the body more susceptible to infection. The new artificial marrow could allow researchers to test how a new drug at certain potencies would affect bone marrow function, Kotov said. This could assist in drug development and catch severe side effects before human drug trials.