Peripheral blood fibrocytes: mesenchymal precursor cells and the pathogenesis of fibrosis.
Peripheral blood fibrocytes are a novel population of cells that rapidly enter sites of tissue injury and contribute to connective scar formation. Fibrocytes display a distinct cell surface phenotype (CD34+/CD45+/collagen I+), and are an abundant source of cytokines and growth factors that function to attract and activate inflammatory and connective tissue cells. Fibrocytes also are specialized to activate naïve T cells against foreign antigen, and may play a critical role in the initiation of cognate immunity during the earliest phases of tissue injury. Recently, immunohistochemical studies of fibrotic tissues have shown that fibrocytes co-localize to areas of connective tissue matrix deposition. Peripheral blood fibrocytes thus may participate in the generation of excessive fibroses associated with various autoimmune disorders involving a persistent T-cell activation, as occurs in scleroderma.
Chesney
J
J
Laboratory of Medical Biochemistry, The Picower Institute for Medical Research, Manhasset, NY 11030, USA. jchesney@picower.edu
Bucala
R
R
D018952:Antigens, CD34 / Q000032:analysis / Q000276:immunology*; D001327:Autoimmune Diseases / Q000276:immunology*; D002478:Cells, Cultured; D003094:Collagen / Q000096:biosynthesis*; D005260:Female; D005347:Fibroblasts / Q000276:immunology*; D005355:Fibrosis / Q000276:immunology*; D006801:Humans; D017493:Leukocyte Common Antigens / Q000032:analysis / Q000276:immunology*; D008213:Lymphocyte Activation; D008297:Male; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index
D018952:Antigens, CD34; D003094:Collagen; D017493:Leukocyte Common Antigens