Collectively, these data indicate that (i) the systemic factor HGFA induce the transition of CH cells into a GALERT state, similarly to its reported effect on other stem/progenitor cell populations, and (ii) injecting mice with rHGFA is sufficient to induce a series of molecular functional changes in BST2pos CH cells, predisposing their functional response to injury. Here, C4B is linked to cyclic hematopoiesis.