Complex multicellular organisms like humans require the generation of billions of cells from a limited number of progenitor cells or stem cells. These progenitor cells then proliferate through mitosis, having specific morphologies and functions and forming into tissues and organs. These cells later specialize and differentiate. However, if proliferation is not properly regulated, various diseases can develop, such as cancer.
Prof. Thomas Marichal, director of the study, and his team from the GIGA Institute at ULiège found out that the ability to proliferate is not limited to stem cells alone but is also present as an unknown function of blood immune cells or monocytes. Monocytes, previously considered as differentiated cells, have the capacity to proliferate and generate a pool of their kind in the tissues to give rise to macrophage or important immune cells that protect us from viruses and microbes and support proper functioning of organs.