Explanatory Interdependence: The Case of Stem Cell Reprogramming

Abstract

Stem cells are defined as undifferentiated cells that can produce both undifferentiated and differentiated (specialized) cells. The stem cell concept is thus intimately connected to core assumptions about the process of development. Making these assumptions explicit clarifies the general explanandum-phenomenon of stem cell biology: the branching pattern of cell development, from a single initiating ‘stem,’ through intermediate stages, to one or more termini. Importantly, the whole process, not only developmental termini (specialized cells of a mature multicellular organism), is the target of explanation. Explanations of cell developmental processes are revealed by experiments. Here I focus on one important kind of experiment: direct cell reprogramming, which manipulates the development of cells in artificial culture conditions. I then examine three accounts of biological explanation in light of this case: interventionist, gene-centric, and mechanistic. Though each offers some insight into explanations based on reprogramming, none is fully satisfactory. This motivates a modified account of mechanistic explanation, emphasizing interdependence among components.