Abstract: A Lin28a activator includes a polysaccharide containing one or more selected from the group consisting of ribose, xylose, and derivatives thereof as an active ingredient. A dedifferentiation inducer of a monocyte includes a macrophage colony-stimulating factor and a polysaccharide containing one or more selected from the group consisting of ribose, xylose, and derivatives thereof as active ingredients. A therapeutic agent against diseases relating to damage in cells, tissues, or organs includes a polysaccharide containing one or more selected from the group consisting of ribose, xylose, and derivatives thereof as an active ingredient. A food or beverage product for preventing or alleviating diseases relating to damage in cells, tissues, or organs includes a polysaccharide containing one or more selected from the group consisting of ribose, xylose, and derivatives thereof.

Abstract: The present invention provides an organ production method including a step of tissue-specifically removing a first portion of an organ of a non-human animal partway through development thereof; a step of transplanting, into a region from which the first portion has been removed, an organ precursor cell which is allogeneic or xenogeneic to the non-human animal; and a step of advancing development of the organ, which is a step in which the transplanted organ precursor cell is differentiated and matured to form a part of the organ.