4. Expression Patterns of Fibrocytes Relative to Vessels During Cutaneous Wound Healing
Naomi Inomata1, Yoshikiyo Akasaka2, Risa Imaizumi1, Emi Okada1, Yu Maruyama1, Yukio Ishikawa2 ,Toshiharu Ishii2 1:Department of Plastic and Reconstructive Surgery, School of Medicine, Toho University, Tokyo, Japan 2:Department of Pathology, School of Medicine, Toho University, Tokyo, Japan
Aims: Fibrocytes (Fbs) are derived from bone marrow cells and are considered as the progenitors of fibroblasts that participate in wound healing. However, the distribution of Fbs in extra- and intravascular regions during healing remains obscure. The present study therefore explored the distribution of circulating Fbs (cFbs) and resident Fbs (rFbs) as well as the distributional relationship between cFbs and vessels during healing. Methods and Results: Forty-nine samples of non-pathological regions of surgically resected human skin wounds were stained for CD34 or leukocyte-specific protein-1 (LSP-1) plus pro-collagen I. Expression recognized by pro-collagen I plus CD34 or LSP-1 obviously differed between Fbs in the extra- and intravascular regions. Intravascular+ Fbs were specifically distributed in arterioles with notably increased CXCL12 in the endothelial cells. Based on the relatively specific distribution of pro-collagen I+/CD34+ circulating Fbs within arterioles/venules, CXCL12-positive arterioles might provide a microenvironment that promotes CXCR4-mediated fibrocyte chemotaxis. Conclusions: The relatively specific distribution of Fbs within arterioles indicates that arterioles provide a microenvironment for cFb recruitment through chemokine interaction.
