title: Reactive response of fibrocytes to vocal fold mucosal injury in rat.
abstract: Fibrocytes hold a prominent role in inflammatory and tissue repair processes in various organ systems. In this study, we identified and quantified a reactive fibrocyte population in the vocal fold mucosa postinjury using immunohistochemistry and stereological analysis. These cells, which expressed CD11b on their surface and prolyl-4-hydroxylase β (P4H-β) intracellularly, were largely restricted to the lamina propria, and were morphologically and immunochemically distinguishable from newly recruited epithelial cells. We validated our immunohistochemistry findings using flow cytometry, and additionally characterized a reactive fibrocyte population in circulating peripheral blood using a novel detection panel (CD16(-) CD11b(+) P4H-β(+) ). Fibrocyte recruitment peaked at 3 days postinjury in peripheral blood, and 5 days postinjury in the vocal fold mucosa. These findings suggest that circulating fibrocytes are recruited to sites of tissue injury in the vocal fold mucosa, and may play an important role in vocal fold tissue repair. The results of this study are consistent with published data from other organ systems and strongly suggest the importance of fibrocytes as therapeutic targets. Our newly reported antigen panel facilitating the direct characterization of fibrocytes via flow cytometry is a useful tool with the potential to facilitate improved study of this cell population.
authors.affiliation: Division of Otolaryngology, Department of Surgery, University of Wisconsin School of Medicine and Public Health, Madison, Wisconsin 53792, USA.
authors.forename: Changying
authors.initials: C
authors.lastname: Ling
authors.forename: Masaru
authors.initials: M
authors.lastname: Yamashita
authors.forename: Jingxian
authors.initials: J
authors.lastname: Zhang
authors.forename: Diane M
authors.initials: DM
authors.lastname: Bless
authors.forename: Nathan V
authors.initials: NV
authors.lastname: Welham
mesh_terms: D000818:Animals; D039481:CD11b Antigen / Q000096:biosynthesis*; D002452:Cell Count; D002454:Cell Differentiation; D002478:Cells, Cultured; D004195:Disease Models, Animal; D005347:Fibroblasts / Q000276:immunology / Q000378:metabolism / Q000473:pathology*; D005434:Flow Cytometry; D007111:Immunity, Cellular; D007820:Laryngeal Mucosa; D008297:Male; D011393:Procollagen-Proline Dioxygenase / Q000096:biosynthesis*; D051381:Rats; D017207:Rats, Sprague-Dawley; D014827:Vocal Cords / Q000276:immunology / Q000293:injuries* / Q000378:metabolism; D014945:Wound Healing / Q000502:physiology*; D014947:Wounds and Injuries / Q000276:immunology / Q000378:metabolism / Q000473:pathology*
chemical_list: D039481:CD11b Antigen; D011393:Procollagen-Proline Dioxygenase