MODULATION OF GROWTH AND FUNCTION OF HUMAN GINGIVAL FIBROBLASTS BY FIBROBLAST-ACTIVATING FACTOR DERIVED FROM PORPHYROMONAS-GINGIVALIS W50

The effect of a 24-kDa fibroblast-activating factor (FAF) isolated from outer membrane vesicles of Porphyromonas gingivalis W50 on the modulation or [H-3]thymidine uptake and cell proliferation was examined in selected fibroblast and transformed cell lines. FAF enhanced the proliferation of human gingival fibroblasts, human skin fibroblasts, and human umbilical vein endothelial cells in subconfluent and confluent cells, suggesting that FAF might be functioning as a competence factor. The transformed cell lines, U-937 and HEp-2, were not responsive. FAF and several human-derived growth factors showed a synergistic effect on proliferation. [H-3]proline and [H-3]leucine were rapidly incorporated into fibroblasts in the presence of FAF; however, there was no selective induction of collagen synthesis. FAF was not active in the induction of interleukin-1 and interleukin-6. It is hypothesized that FAF from P. gingivalis functions as a growth factor for human fibroblasts but is without activity for transformed cells.