Figure 2.

Depletion of macrophages or senescent cells has diverse and opposing effects on organ regeneration. The effects of senescent cell depletion (a) or macrophage depletion or prevention of accumulation (b) are depicted. In many organs, the timing of cell depletion has a crucial role on the regenerative outcome. While senescent cell depletion delays cutaneous wound healing and exacerbates fibrosis [60,61], the effect of deletion of macrophages during wound healing is timing-dependent [54]; similarly while senescent cell depletion leads to liver fibrosis [28,62], depletion of macrophages can lead to both reduced liver scarring and fibrosis, dependent on timing [52]. Moreover, senescent cell removal has no or largely positive effects on muscle and heart [63]; however, macrophage depletion leads to detrimental effects on heart and muscle regeneration [63–65]. Created with Biorender.com.