Mechanisms of wound healing responses in lupus-prone New Zealand White mouse strain

Host responses to synthetic implants are analogous to healing, the process of repair that follows injury. Normally, the processes of wound healing follow well-established patterns but conditions such as autoimmune diseases profoundly affect tissue repair. We have analyzed sponge-induced wound healing responses in lupus-prone New Zealand White and control (Balb/c) mouse strains by measuring inflammation, extracellular matrix deposition, angiogenesis, and cytokine production in polyether-polyurethane sponge implanted subcutaneously in male mice of these two strains. Although there was no difference in the gross appearance of the implants, further analysis of the wound healing responses, induced from 7 to 21 days post implantation, disclosed important differences between the New Zealand White and Balb/c strains. The intensity of inflammation (circulating tumor necrosis factor-alpha and inflammatory leukocytes levels) was lower but implant fibrosis (collagen and transforming growth factor-beta 1) was higher in New Zealand White, compared with Balb/c mice. Angiogenesis (hemoglobin, vascular endothelial growth factor, and vascularity) in New Zealand White implants peaked earlier than in Balb/c mice. In conclusion, we have shown that wound healing responses are clearly different in this strain of lupus-prone mice and suggest that this pattern of repair was critically influenced by impaired inflammation and accelerated angiogenesis in the New Zealand White strain.