Chondrogenic Potential of CD90+ Progenitors Figure 2. Chondrogenic Differentiation of CD90+/2 sfMPCs. sfMPCs derived from normal synovial fluid were enriched/depleted for CD90 and induced to differentiate into chondrocytes. The CD90+ fraction expressed (A,F,K,P) similar levels of Sox9, Collagen 2 and Aggrecan mRNA on day 14 to the total sMPC population (Figure 2), whereas the CD902 fraction demonstrated reduced levels of Sox9, Collagen 2 and Aggrecan (A,F,K,P). Alcian PLOS ONE | www.plosone.org 4 August 2012 | Volume 7 | Issue 8 | e43616