The Chondrogenic Potential of Progenitor Cells Derived from Peripheral Blood: A Systematic Review.

An increasing number of studies have detected mesenchymal stromal cells (MSCs) and mesenchymal progenitor cells (MPCs) in the peripheral blood (PB). This study aimed to systematically review the possibility of using the PB as a source for chondrogenic progenitors. PubMed, the Web of Science, and Embase were searched for relevant articles. The findings of the studies were reviewed to evaluate the biological characteristics of PB-derived MSCs, chondrogenic MPCs, and their applications in cartilage repair. Thirty-six articles were included in the final analysis, 29 of which indicated that PB is a potential source for chondrogenic progenitor cells. Thirty-two studies reporting in vitro data, including 79.2% (19/24) of studies on PB MSCs and 75% (6/8) of studies on chondrogenic PB MPCs, confirmed the existence of PB MSCs and PB MPCs, respectively; all in vivo investigations showed that using PB as a cell source enhanced cartilage repair. PB MSCs were found in most of the animal studies (12/13), whereas 7 of 11 human studies described the presence of PB MSCs. This systematic review strongly indicates the existence of MSCs in the PB of animals, whereas the presence of MSCs in human PB is less clear. Although the presence of both MSCs and chondrogenic MPCs in the PB, as well as a few favorable outcomes associated with the use of PB-derived progenitors for cartilage repair in vivo, suggests that the PB is a potential alternative source of chondrogenic progenitor cells for cartilage repair, the efficacy of these cells has not been compared to those from other sources, such as bone marrow or adipose tissue in controlled studies.