期刊名称：Proceedings of the National Academy of Sciences
印刷版ISSN：0027-8424
电子版ISSN：1091-6490
出版年度：1991
卷号：88
期号：24
页码：11007-11011
DOI：10.1073/pnas.88.24.11007
语种：English
出版社：The National Academy of Sciences of the United States of America
摘要：Basic fibroblast growth factor (bFGF), a protein with angiogenic, mitogenic, and chemotactic properties, lacks a signal sequence and is not secreted via the classical secretory pathway. However, the growth factor is known to act extracellularly. Since no defined mechanism for bFGF release has been described, it has been suggested that this growth factor is released from dead or damaged cells. To test this hypothesis we characterized the effect of exogenously added bFGF and neutralizing antibody on the migration of single, isolated NIH 3T3 cells transfected with bFGF cDNA. Under these conditions the observed cell cannot be affected by bFGF derived from other cells. Cells were seeded onto colloidal gold-coated coverslips at a density of one cell per coverslip. A cell migrating on this substrate produces a track free of refringent gold particles that is measured by an image analyzer. The results showed that cell motility directly correlated with the amount of bFGF released from the migrating cells. Affinity-purified anti-bFGF antibody, but not irrelevant IgG, reduced the level of migration of the bFGF transfectants to that of the control cells transfected with the vector alone, showing that bFGF stimulates migration of the cell that releases it. Thus, bFGF is secreted by viable cells and mediates cell functions via a "true" autocrine mechanism.
