RT Journal Article T1 Combined blockade of complement C5 and TLR co-receptor CD14 synergistically inhibits pig-to-human corneal xenograft induced innate inflammatory responses. A1 Islam, Rakibul A1 Islam, Mohammad Mirazul A1 Nilsson, Per H A1 Mohlin, Camilla A1 Hagen, Kjersti Thorvaldsen A1 Paschalis, Eleftherios I A1 Woods, Russell L A1 Bhowmick, Sabuj Chandra A1 Dohlman, Claes H A1 Espevik, Terje A1 Chodosh, James A1 Gonzalez-Andrades, Miguel A1 Mollnes, Tom Eirik K1 Biomaterial K1 Complement system K1 Cornea K1 Cytokine K1 Decellularization K1 Regenerative medicine K1 Toll-like receptor K1 Xenotransplantation AB Inadequate supplies of donor corneas have evoked an escalating interest in corneal xenotransplantation. However, innate immune responses contribute significantly to the mechanism of xenograft rejection. We hypothesized that complement component C5 and TLR co-receptor CD14 inhibition would inhibit porcine cornea induced innate immune responses. Therefore, we measured cytokine release in human blood, induced by three forms of corneal xenografts with or without inhibitors. Native porcine cornea (NPC) induced interleukins (IL-1β, IL-2, IL-6, IL-8, IL-1ra), chemokines (MCP-1, MIP-1α, MIP-1β) and other cytokines (TNF, G-CSF, INF-γ, FGF-basic). Decellularized (DPC) and gamma-irradiated cornea (g-DPC) elevated the release of those cytokines. C5-blockade by eculizumab inhibited all the cytokines except G-CSF when induced by NPC. However, C5-blockade failed to reduce DPC and g-DPC induced cytokines. Blockade of CD14 inhibited DPC-induced cytokines except for IL-8, MCP-1, MIP-1α, and G-CSF, while it inhibited all of them when induced by g-DPC. Combined blockade of C5 and CD14 inhibited the maximum number of cytokines regardless of the xenograft type. Finally, by using the TLR4 specific inhibitor Eritoran, we showed that TLR4 activation was the basis for the CD14 effect. Thus, blockade of C5, when combined with TLR4 inhibition, may have therapeutic potential in pig-to-human corneal xenotransplantation. STATEMENT OF SIGNIFICANCE: Bio-engineered corneal xenografts are on the verge of becoming a viable alternative to allogenic human-donor-cornea, but the host's innate immune response is still a critical barrier for graft acceptance. By overruling this barrier, limited graft availability would no longer be an issue for treating corneal diseases. We showed that the xenograft induced inflammation is initiated by the complement system and toll-like receptor activation. Intriguingly, the inflammatory response was efficiently blocked by simultaneously targeting bottleneck molecules in the complement system (C5) and the TLR co-receptor CD14 with pharmaceutical inhibitors. We postulate that a combination of C5 and CD14 inhibition could have a great therapeutic potential to overcome the immunologic barrier in pig-to-human corneal xenotransplantation. PB Elsevier YR 2021 FD 2021-03-19 LK http://hdl.handle.net/10668/17429 UL http://hdl.handle.net/10668/17429 LA en NO Islam R, Islam MM, Nilsson PH, Mohlin C, Hagen KT, Paschalis EI, et al. Combined blockade of complement C5 and TLR co-receptor CD14 synergistically inhibits pig-to-human corneal xenograft induced innate inflammatory responses. Acta Biomater. 2021 Jun;127:169-179 DS RISalud RD Apr 4, 2025