BASIC FIBROBLAST GROWTH-FACTOR IMMUNOREACTIVITY IN BLOOD-VESSELS AND CELLS OF DISC HERNIATIONS

Study Design. Basic fibroblast growth factor immunoreactivity was stud ied in disc herniation tissue. Objectives. The first objective was to analyze in which tissue components, if any, fibroblast growth factor i s expressed in the disc herniation. The second objective was to compar e such expression with that in fresh cadaver disc tissue. Summary of B ackground Data. Disc herniation tissue contains vascular ingrowth, whi ch promotes the formation of granulation tissue. Fibroblast growth fac tor is a potent inducer of angiogenesis and also regulates extracellul ar proteolysis. Methods. Twenty-seven disc herniation tissue and five macroscopically normal fresh cadaver discs were treated with an identi cal immunohistochemical protocol. Serial frozen sections were stained with a polyclonal basic fibroblast growth factor antibody and a polycl onal antibody to von Willebrand factor, which localizes endothelial ce lls. The immunostaining data were compared with relevant clinical data . Results. Histologically, 74% of the samples contained anulus fibrosu s and 59% nucleus pulposus. Basic fibroblast growth factor immunoreact ivity was detected in 81% of the samples. There were immunopositive sm all blood vessels and scattered immunopositive disc cells (67%). Not a ll observed blood vessels were basic fibroblast growth factor immunopo sitive. In control discs, no immunoreactivity was observed. Conclusion s. The observed presence of fibroblast growth factor in small blood ve ssels suggests an active angiogenesis as a result of disc injury. Cell ular expression of fibroblast growth factor may be linked to proteolyt ic activity in disc extracellular matrix.