Evaluation of a near-senescent human dermal fibroblast cell line and effect of amelogenin.
BACKGROUND
Fibroblast senescence may delay healing of chronic wounds.


OBJECTIVE
To characterize a chronic human dermal fibroblast cell line (CRL-7815) with near-senescent properties, cell proliferation and production of wound-healing modulating cytokines, and biosynthesis and remodelling of collagen were compared with normal human dermal fibroblasts. Also, the response of CRL-7815 fibroblasts to the extracellular matrix protein amelogenin that is beneficial in the treatment of stalled chronic wounds was studied.


METHODS
Fibroblast proliferation was monitored by time-resolved growth curves and factors secreted into the culture medium containing 10% fetal bovine serum were measured by enzyme-linked immunosorbent assays. Fibroblast-mediated reorganization was examined in three-dimensional type I collagen matrices.


RESULTS
Cell proliferation over 9 days was significantly (P < 0.01) slower for CRL-7815 than for normal fibroblasts. Amelogenin at 1 mg mL(-1) increased (P < 0.01) CRL-7815 proliferation to the level of the normal fibroblasts. The neutrophil chemoattractant interleukin (IL)-8 was low while the constitutive production of monocyte chemoattractant protein (MCP)-1 was highly elevated in medium from cultured CRL-7815 fibroblasts. Amelogenin augmented IL-8 but attenuated MCP-1 secretion in CRL-7815 fibroblasts. The elevated vascular endothelial growth factor production in CRL-7815 fibroblasts was further increased with amelogenin while increased type I collagen synthesis by CRL-7815 was reduced with 0.1 mg mL(-1) amelogenin. The dramatically impaired collagen matrix remodelling with CRL-7815 fibroblasts (P < 0.001) was slightly improved with amelogenin (P = 0.0011).


CONCLUSIONS
The near-senescent cell line CRL-7815 shares functional anomalies with fibroblasts isolated from nonhealing chronic cutaneous wounds. Amelogenin has the capacity to switch chronic fibroblasts into an acute-like phenotype.
Almqvist
S
S
Department of Biomaterials, Sahlgrenska Academy at Göteborg University, Sweden.
Werthén
M
M
Johansson
A
A
Törnqvist
J
J
Agren
M S
MS
Thomsen
P
P
D000328:Adult; D000369:Aged, 80 and over; D053523:Amelogenin / Q000494:pharmacology*; D019540:Area Under Curve; D002460:Cell Line / Q000187:drug effects / Q000378:metabolism; D049109:Cell Proliferation / Q000187:drug effects*; D002478:Cells, Cultured; D016922:Cellular Senescence / Q000502:physiology*; D018932:Chemokine CCL2 / Q000096:biosynthesis; D024042:Collagen Type I / Q000096:biosynthesis; D005260:Female; D005347:Fibroblasts / Q000187:drug effects / Q000502:physiology*; D006801:Humans; D016209:Interleukin-8 / Q000096:biosynthesis; D008297:Male; D042461:Vascular Endothelial Growth Factor A / Q000096:biosynthesis
D053523:Amelogenin; D018932:Chemokine CCL2; D024042:Collagen Type I; D016209:Interleukin-8; D042461:Vascular Endothelial Growth Factor A