Characterization of fibronectin and fibrin(ogen) fragments in gingival crevicular fluid

Abstract

A total of 49 crevicular fluid (CF) samples were collected with paper strips from 12 healthy adults. Each sample was eluted into sterile saline and two aliquots were drawn for SDS–PAGE, one for fibronectin and one for fibrin analysis. Peptides were transferred to nitrocellulose membranes, and fibronectin and fibrin were detected using specific antibodies. The relative amounts of different molecular forms of fibronectin and fibrin were analyzed using a laser densitometer. After the sample collection, Plaque Index, Papilla Bleeding Index and pocket depth were measured. Bone loss was estimated from the orthopantho‐mograms. Fibronectin fragments were seen in all CF samples. Intact fibronectin was seen in 21 samples, of which 76% were collected from periodontitis‐affected sites. There was a positive correlation between the proportion of intact fibronectin and the clinical parameters. Intact fibrin and fibrin fragments were seen in all samples. Fibrin‐positive material with larger molecular weight than intact fibrin was also seen in all samples. A negative correlation was found between the proportion of intact fibrin and the clinical parameters. There was no correlation between total amounts and concentrations of fibronectin and fibrin. Molecular forms of fibronectin and fibrin may affect the pathogenesis and healing of periodontal diseases, since the biologic effects of the fragments of these molecules differ from those of the intact molecules.

Fibrin Mimics Neutrophil Extracellular Traps in SEM

“…Fibrin formation is common in inflamed sites [18,19] and fibrin shows a web-like appearance in SEM [20,21]. Fibrin has also been reported in inflammatory gingival exudate [22,23]. The lack of fibrin in the purulent crevicular exudate might be due to excessive quantities of the NET elastase [3], which efficiently digests fibrin [24,25].…”

Hypothesis: The Humoral Immune Response to Oral Bacteria Provides a Stimulus for the Development of Rheumatoid Arthritis

“…The capacity to break down fibrin via PAD may in fact promote survival of P. gingivalis, since fibrin-related extracellular deposits constitute a major component of the fibrous tissue band surrounding the lesion (75). A negative correlation has been established between the proportion of intact fibrin in crevicular fluid and the clinical measures of periodontal inflammation (76). Concentrations of fibrin degradation products have been measured at levels comparable to those seen in rheumatoid synovial fluid (76).…”

“…A negative correlation has been established between the proportion of intact fibrin in crevicular fluid and the clinical measures of periodontal inflammation (76). Concentrations of fibrin degradation products have been measured at levels comparable to those seen in rheumatoid synovial fluid (76).…”

Mutations in the Heparin Binding Domain of Fibronectin in Cooperation with the V Region Induce Decreases in pp125 Levels Plus Proteoglycan-mediated Apoptosis via Caspases

“…In addition, these data further support the idea that intact FN has functions distinct from those of its fragments, which may have profound implications for wound-healing dynamics and inflammatory diseases. In periodontal disease, for example, inflammatory cytokines and bacterial products would stimulate fibroblasts of the periodontium to express greater amounts of matrix metalloproteinases (44), which in turn would degrade the extracellular matrix, thereby generating FN fragments (8,9). From our own studies and those of others, we know that FN fragments can on their own also induce elevated matrix metalloproteinase expression (1, 2) and tissue destruction in vitro (3) and suppress cell proliferation and chemotaxis (45), functions not normally observed with intact FN.…”

“…For example, the central cell binding domain of FN (FN 120) induces rabbit synovial fibroblasts (1) and human fibroblasts (2) to express elevated levels of matrix metalloproteinases, whereas fragments from the amino-terminal and gelatin binding domains induce chondrolysis in vitro, the latter effect presumably through matrix metalloproteinase and serine proteinase induction (3,4). These FN fragments are also associated with chronic inflammatory states in vivo, since high levels of such fragments have been found in synovial fluids from arthritic patients (5-7) and in gingival crevicular fluid from patients with periodontitis (8,9).…”