Fibronectin fragmentation is a feature of periodontal disease sites and diabetic foot and leg wounds and modifies cell behavior.
BACKGROUND
Fibronectin (FN) undergoes fragmentation in periodontal disease sites and in poorly healing diabetic wounds. The biologic effects of FN fragments on wound healing remain unresolved. This study characterized the pattern of FN fragmentation and its effects on cellular behavior compared to intact FN.


METHODS
Polyclonal antibodies were raised against FN and three defined recombinant segments of FN and used to analyze gingival crevicular fluid from periodontal disease sites in systemically healthy subjects and in subjects with diabetes, as well as chronic leg and foot wound exudates from subjects with diabetes. Subsequently, the behavior of human gingival fibroblasts (hGFs) and HT1080 reference cells were analyzed by measuring cell attachment, migration, and chemotaxis in the presence of intact FN or recombinant FN fragments.


RESULTS
FN fragmentation was evident in fluids from periodontal disease sites and diabetic leg and foot wounds. However, no fragmentation pattern distinguished systemically healthy subjects from subjects with diabetes. hGFs and HT1080 cells required significantly higher concentrations of FN fragments to achieve attachment comparable to intact FN. Cells cultured on FN fragments also were morphologically different from cells cultured on full-length FN. Migration was reduced for hGFs cultured on FN fragments relative to full-length FN. In contrast, FN fragments increased HT1080 fibrosarcoma cell migration over intact FN.


CONCLUSIONS
FN fragmentation is a prominent feature of periodontal and chronic leg and foot wounds in diabetes. Furthermore, cell culture assays confirmed the hypothesis that exposure to defined FN fragments significantly alters cell behavior.
Stanley
Corey M
CM
Department of Periodontics, University of Texas Health Science Center at San Antonio, 7703 Floyd Curl Drive, San Antonio, TX 78229, USA.
Wang
Yao
Y
Pal
Sanjay
S
Klebe
Robert J
RJ
Harkless
Lawrence B
LB
Xu
Xiaoping
X
Chen
Zhihua
Z
Steffensen
Bjorn
B
D000328:Adult; D000368:Aged; D016301:Alveolar Bone Loss / Q000378:metabolism; D016022:Case-Control Studies; D002478:Cells, Cultured; D003924:Diabetes Mellitus, Type 2 / Q000150:complications / Q000378:metabolism*; D017719:Diabetic Foot / Q000150:complications / Q000378:metabolism; D005260:Female; D005347:Fibroblasts / Q000502:physiology; D005353:Fibronectins / Q000378:metabolism*; D005883:Gingival Crevicular Fluid / Q000378:metabolism*; D006801:Humans; D007871:Leg Ulcer / Q000150:complications / Q000378:metabolism*; D008297:Male; D008875:Middle Aged; D010446:Peptide Fragments / Q000302:isolation & purification / Q000378:metabolism; D010510:Periodontal Diseases / Q000150:complications / Q000378:metabolism*; D010519:Periodontium / Q000166:cytology / Q000378:metabolism; D011994:Recombinant Proteins; D012016:Reference Values; D018709:Statistics, Nonparametric
D005353:Fibronectins; D010446:Peptide Fragments; D011994:Recombinant Proteins