Perlecan Delineates Stem Cell Niches in Human Foetal Hip, Knee and Elbow Cartilage Rudiments and Has Potential Roles in the Regulation of Stem Cell Differentiation

This is the authors' abstract. We don't add key points for this paper.

This study immunolocalized perlecan, Type I and II collagen and aggrecan in human foetal joint rudiment cartilages of the hip, knee and elbow. Blood vessels in the stromal tissues, associated with the cartilage rudiments were also prominently stained with perlecan, entrapped red blood cells aided in their identification. Perlecan was a prominent extracellular matrix proteoglycan in the rudiment cartilages. Stem cell niches close to the margins of the cartilage rudiments were prominently identified in the hip, knee and elbow and were distinguishable from the aforementioned blood vessels which were located in the rudiment associated stromal tissues. Type I collagen was also immunolocalized to the outer margins of the rudiment cartilages where perlecan positive niches were also present whereas the remainder of the rudiment contained type II collagen. Stem cell niches similar to those observed in the present study have previously been identified in the human foetal elbow.