Cleaved inflammatory lactoferrin peptides in parotid saliva of periodontitis patients.
Lactoferrin (Lf) is a member of the transferrin family of iron-binding anti-bacterial proteins, present in most exocrine secretions, such as saliva, and plays an important role in mucosal defense. In this study, we identified small Lf peptides with Con A low-affinity in the parotid saliva of chronic periodontitis patients by Con A two-dimensional immunoelectrophoresis, Con A affinity chromatography and Western blotting using anti-human Lf polyclonal Ab. N-terminal amino acid sequencing of the four Con A low-affinity Lf peptides confirmed them to be fragments of intact Lf. The detection ratio of the proteinase 3 (PR3)-like activity was elevated in the parotid saliva of periodontitis patients and was associated with the severity of clinical symptoms. PR3 protein was also detected in the parotid saliva of periodontitis patients, and PR3, but not human leukocyte elastase and cathepsin G, degraded intact Lf. Con A low-affinity saliva Lf peptides showed no anti-bacterial activity against Escherichia coli, and had a reduced iron-chelating capacity. Con A low-affinity saliva Lf peptides, PR3-treated Lf preparation and two of four synthetic polypeptides induced the production of interleukin IL-6, monocyte chemoattractant protein-1 and IL-8, and the activation of NF-kappaB in human oral epithelial HSC-2 cells. Furthermore, concentrations of the Lf peptides in the parotid saliva of periodontitis patients were increased with a correlation to the severity of clinical symptoms. These results suggest that Lf in the parotid saliva of periodontitis patients was degraded into small peptides by the PR3-like activity with the capability to induce inflammatory mediators.
Komine
Ken-Ichi
K
Division of Oral Immunology, Department of Oral Biology, Tohoku University Graduate School of Dentistry, 4-1 Seiryo-machi, Aoba-ku, Sendai 980-8575, Japan.
Kuroishi
Toshinobu
T
Ozawa
Akiko
A
Komine
Yumiko
Y
Minami
Takumi
T
Shimauchi
Hidetoshi
H
Sugawara
Shunji
S
D000595:Amino Acid Sequence; D018925:Chemokines / Q000378:metabolism; D003208:Concanavalin A / Q000737:chemistry; D016207:Cytokines / Q000378:metabolism; D015180:Electrophoresis, Gel, Two-Dimensional; D006801:Humans; D007781:Lactoferrin / Q000737:chemistry / Q000378:metabolism*; D008969:Molecular Sequence Data; D009061:Mouth Mucosa / Q000187:drug effects / Q000276:immunology; D053146:Myeloblastin / Q000378:metabolism*; D016328:NF-kappa B / Q000378:metabolism; D010306:Parotid Gland / Q000378:metabolism*; D010446:Peptide Fragments / Q000032:analysis* / Q000494:pharmacology; D010518:Periodontitis / Q000175:diagnosis / Q000378:metabolism*; D012463:Saliva / Q000737:chemistry*
D018925:Chemokines; D016207:Cytokines; D016328:NF-kappa B; D010446:Peptide Fragments; D003208:Concanavalin A; D007781:Lactoferrin; D053146:Myeloblastin