Basic Science Secreted phosphoprotein 24 kD inhibits nerve root inflammation induced by bone morphogenetic protein-2

BACKGROUND CONTEXT: Bone morphogenetic protein-2 (BMP-2) has been used to successfully promote spine fusion, but side-effects including nerve inflammation have been observed. PURPOSE: To investigate the direct neurotoxic effects of BMP-2 and test the hypotheses that the use of BMP binding proteins, such as secreted phosphoprotein 24 kD (Spp24), can reduce or eliminate these effects. STUDY DESIGN: In vitro experiments and in vivo analysis in a rodent model. FDA device/drug status: Not applicable. Author disclosures: HT: Nothing to disclose. C-SL: Nothing to disclose. TPS: Nothing to disclose. SRM: Nothing to disclose. KP: Nothing to disclose. LL: Nothing to disclose. WZ: Nothing to disclose. YL: Nothing to disclose. TH: Nothing to disclose. ST: Fellowship Support: AO Spine (B). RA: Nothing to disclose. MR: Nothing to disclose. K-WZ: Nothing to disclose. EJB: Grants: Dept. VA (G, Paid directly to institution). SSM: Grants: Dept. VA (F, Paid directly to institution). JCW: Royalties: Stryker (B), Osprey (C), Aesculap (B), Biomet (F), Amedica (D), Seaspine (D), Synthes (C), Alphatech (E); Stock Ownership: Fziomed (2,500 shares, less than 1%), Alphatech (14,619 shares, less than 1%); Private Investments: Promethean Spine (B investment, less than 1% of entity, unknown amount of shares), Paradigm Spine (B investment, less than 1% of entity, unknown amount of shares), Benevenue (C investment, less than 1% of entity, unknown amount of shares), Nexgen (B investment, less than 1% of entity, unknown amount of shares), Pioneer (B investment, less than 1% of entity, unknown amount of shares), Amedica (D investment, less than 1% of entity, unknown amount of shares), Vertiflex (B investment, less than 1% of entity, unknown amount of shares), Electrocore (C investment, less than 1% of entity, unknown amount of shares), Surgitech (C investment, less than 1% of entity, unknown amount of shares), Axiomed (25,000 shares, less than 1% of entity), VG Innovations (5,000 options, less than 1% of entity), Corespine (2,000 options valued at less than 1% of company), Expanding Ortho (33,000 options valued at less than 1% of company), Syndicom (66,125 shares valued at less than 1% of company), Osprey (10 options, less than 1% of company), Amedica (35,416 options, less than 1% of company), Bone Biologics (51,255 shares, less than 1% of company), Curative Biosciences (1,875 options, less than 1% of company), Pearldriver (25,000 options, less than 1% of company); Board of Directors: NASS (nonfinancial, reimbursement for travel for board meetings), CSRS (nonfinancial, reimbursement for travel for board meetings), AO Founda