Li activated nanohydroxyapatite doped with Eu ions enhances proliferative activity and viability of human stem progenitor cells of adipose tissue and olfactory ensheathing cells. Further perspective of nHAP:Li, Eu application in theranostics.

Spinal cord injuries (SCI) often require simultaneous regeneration of nerve tissue and bone. Hydroxyapatites are described as bioresorbable materials with proper biocompatibility and osteoconductivity, therefore its application for spinal surgery is considered. In this paper, we present repeatable method for developing nanocrystalline calcium hydroxyapatites structurally modified with Li ions (nHAP:Li). Obtained biomaterials were profoundly characterized in terms of their physicochemical properties. Moreover, we have shown that nHAP:Li doped with europium (Eu) may serve as a theranostic agent, what additionally extend its potential usage for SCI treatment. The biocompatibility of nHAP:Li was determined using human olfactory ensheathing cells (hOECs) and adipose tissue-derived multipotent stromal cells (hASCs). Both population of cells are eagerly applied for cell-based therapies in SCI, mainly due to their paracrine activity. The extensive in vitro studies showed that nHAP:Li promotes the cells proliferation, viability and cell-cell interactions. Obtained results provides encouraging approach that may have potential application in regenerative medicine and that could fulfil the promise of personalized medicine - important in SCI treatment.