According to a recent study, blood stem cells can not only revive haemocytes, but may even help in the production of white blood cells during an infection or inflammation. This newly-discovered role of hematopoietic stem cells has given rise to a novel method through which the body can fight against infections.
The research was conducted by Inserm, CNRS and MDC, led by Michael Sieweke of the Centre d’Immunologie de Marseille Luminy and Max Delbruck Centre for Molecular Medicine. This specific group of stem cells has the ability to protect patients undergoing bone marrow transplantation against infections till the immune system returns to normalcy.
The three types of blood cells are responsible for carrying oxygen, defending the body, and forming blood clots, respectively. However, each of these cells has a short lifetime and is replenished in the blood from time to time. For this reason, the body must properly manage the entire process of cell replacement, which is performed by the blood/hematopoietic stem cells situated in the bone marrow. The stem cells on a daily basis produce and release new cells into the bloodstream.
The main aim of the study is to know how the blood stem cells multiply and differentiate to produce red blood cells, white blood cells and platelets. The researchers feel that an interplay of certain factors and environmental signals leads to differentiation of the cells.
During an infection or inflammation, the stem cells respond to emergencies by producing a biological molecule called M-CSF (Macrophage Colony-Stimulating Factor) in large amounts. Here, the PU.1 gene is activated and the stem cells immediately produce the cells required for the situation. This could definitely help to control the risk of acute infection in the future.
The discovery is absolutely original in terms of its technology and approach. In this experiment, the research team had to carefully observe any kind of modification in the cells. However, the most challenging aspect of this study is that the stem cells are rare and indistinguishable. In order to know the status of the myeloid cell switch or protein PU.1, a fluorescent marker is used. When the cells were recovered, the researchers noticed that the myeloid genes were activated in all them.