Industrial approach in developing an advanced therapy product for bone repair

Mesenchymal stem cells (MSCs) are multipotent cells with therapeutic applications. The aim of our work was to develop an advanced therapy product for bone repair, associating autologous human adipose-derived MSCs (ASCs) with human bone allograft (TBF; Phoenix). We drew up specifications that studied: (a) the influence of tissue collection procedures (elective liposuction or non-invasive resection) and patient age on cell number and function; (b) monolayer cell culture conditions and osteodifferentiation and particularly the possibility of reducing stages of culture; and (c) the bone construct preparation and especially the comparison between two types of cells seeded on bone allograft (number of cultured processed lipoaspirate (PLA) cells and monolayer-expanded ASCs) and cultured for 1, 2 and 3 weeks. The results showed that tissue harvesting techniques and patient age did not affect PLA cell number and ASC cloning efficiency. PLA cells can be directly osteodifferentiated (instead of culturing them in expansion medium first and then differentiating them) and these cells were able to mineralize when they were cultured in an osteogenic medium containing calcium chloride. PLA cells directly seeded on bone allograft for a minimum of 3 weeks of culture in this osteogenic medium expressed osteocalcin and colonized the matrix better than monolayer-expanded ASCs. This work detailed the specifications of a pharmaceutical laboratory to develop an advanced therapy product and this current approach is promising for bone repair.