Calprotectin and lactoferrin levels in the gingival crevicular fluid of children

Activity of five antimicrobial peptides against periodontal as well as non-periodontal pathogenic strains

Background: Due to the increasing emergence of multi-resistant bacteria the search for alternative antimicrobial substances is of high interest. Promising agents are antimicrobial peptides which are host defense molecules of the innate immune system in a wide range of different species. Objectives: The aim of this study was to assess the activity of nisin, melittin, lactoferrin, parasin-1 and LL-37 against 35 oral bacteria and Candida albicans employing the gold standard method for anaerobic susceptibility testing. Methods: The activity of the peptides was determined by an agar dilution method under anaerobic and aerobic conditions. The test media contained final peptide concentrations between 0.125 µg/ml and 8 µg/ml (melittin, lactoferrin, parasin-1, LL-37) and between 0.125 µg/ml and 128 µg/ml (nisin). Results: Nisin completely inhibited the growth of Megasphaera sp., Bifidobacterium longum, Parvimonas micra, Actinomyces israelii, Actinomyces naeslundii, Actinomyces odontolyticus, Prevotella intermedia, Streptococcus anginosus, Streptococcus constellatus and Staphylococcus aureus. Melittin and lactoferrin reduced the growth of Megasphaera sp., P. micra, B. longum (melittin) and Selenomonas flueggei (lactoferrin). Parasin-1 and LL-37 showed no activity. Conclusion: AMPs, especially nisin and to a smaller degree lactoferrin, might be promising alternatives to antibiotics because of their antimicrobial activity, high resistance to environmental conditions and partially low costs.

Role of Calprotectin as a Biomarker in Periodontal Disease

Periodontal disease (PD) is a common infectious and inflammatory disease characterised by inflammation of tissues surrounding and supporting the teeth and destruction of the associated alveolar bone, eventually resulting in tooth loss. This disease is caused by periodontopathic bacteria in plaque biofilm and resultant innate and adaptive immune responses in periodontal tissues. Calprotectin (CLP) is a calcium-binding protein of the S-100 protein family and is found to be induced by activated granulocytes, monocytes, and epithelial cells. CLP has been shown to play an important role in numerous inflammatory diseases and disorders. Increasing evidence indicates that CLP is involved in the progression of PD, and its levels may be associated with disease severity and outcome of periodontal treatments. This review will summarise recent studies regarding the presence, regulation, and function of CLP in PD. The findings indicate that CLP may be an effective biomarker for diagnosis and treatment for the PD.

Myeloid-related protein (MRP8/14) expression in gingival crevice fluid in periodontal health and disease and after treatment

BACKGROUND AND OBJECTIVE

Myeloid-related protein (MRP8/14) and its subunits are biomarkers of inflammation. The present study evaluated whether gingival crevice fluid levels of these markers discriminate periodontitis from healthy sites in patients with chronic periodontitis or diseased from healthy subjects, and whether these biomarkers detect longitudinal changes after therapy.

MATERIAL AND METHODS

Levels of MRP8/14, MRP14 and total protein were quantified in 19 periodontitis patients before non-surgical periodontal therapy, after 3 and 6 mo of treatment, and were measured once in 11 periodontally healthy subjects. In total, diseased subjects contributed 59 sites with probing depths >4 mm (PP) and 21 sites <4 mm (PH); healthy subjects contributed 91 sites (HH).

RESULTS

Overall, in diseased subjects, MRP8/14, MRP14 and total protein were not significantly different between PP and PH sites. However, at baseline, MRP8/14 and total protein had significantly higher values at sites in periodontally diseased than in healthy subjects. Clinical improvement was associated with a significant decrease of MRP8/14 and MRP14 from baseline to month 6 in PP sites. Interestingly, a similar decrease was observed in PH sites for all three markers. At 6 mo, however, levels of MRP8/14 and protein in PP and PH sites of patients were still significantly higher than in healthy subjects.

CONCLUSION

Gingival crevice fluid levels of MRP8/14 did not differentiate between clinically diseased and healthy sites in patients with chronic periodontitis. However, this marker was elevated in periodontally diseased compared with healthy subjects, and its values decreased following therapy. MRP8/14 may be used to monitor the response to treatment.

Clinical manifestations associated with high titer of anti-streptolysin O in Behcet's disease

To evaluate the association of chronic infection with clinical features of Behcet's disease (BD), we studied epidemiological and clinical features of 149 patients with only aphthous ulcer and 294 patients with BD. The incidence of chronic infection history was compared between both groups with age- and sex-matching and clinical manifestations of BD associated with high anti-streptolysin O (ASO) titer were investigated. BD patients had more common history of tonsillitis and dental caries than aphthous ulcer patients (P = 0.002 and P = 0.043, respectively). BD patients with persistently high anti-streptolysin O titers had more frequent history of tonsillitis (P = 0.001, odds ratio [OR] = 2.99, 95% confidence interval [CI] 1.53-5.82) and erythema nodosum (EN)-like lesions (P = 0.001, OR = 3.02, 95% CI 1.54-5.93) and fewer history of genital ulcer (P = 0.027, OR = 0.21, 95% CI 0.05-0.84) than BD patients with normal anti-streptolysin O titer. Our results suggest persistently high ASO titers in BD patients could indicate that streptococcal infections such as tonsillitis are related to BD symptoms such as EN-like lesions. In these patients, ASO titer can be used in the evaluation of BD disease activity and antibiotic treatments might be effective to control the symptoms of BD.

Correlation between single nucleotide polymorphisms in a calprotectin subunit gene and risk of periodontitis in a Chinese population

S100A8, the light subunit of calprotectin, has been known to be associated with periodontal inflammation. The present study looked to detect whether three polymorphisms in the upstream region of the S100A8 gene are correlated with periodontitis. Three hundred and twenty one subjects, including chronic periodontitis (CP) patients, aggressive periodontitis (AgP) patients and periodontally healthy controls, were recruited. The SNPs rs3795391, rs3806232 and rs3885688 were analyzed by PCR-RFLP analysis. No person carried the rs3885688 polymorphism in this cohort. For the other two polymorphisms, the combined effects of genotype/allele and gender were shown to be associated with the risk of periodontitis using multivariate logistic regression analysis. The G+ genotype/G allele may be considered to exert a significant protective effect in males against AgP (Genotype: rs3795391: P= 0.032, rs3806232: P= 0.017; Allele: rs3795391: P= 0.024, rs3806232: P= 0.013). Although the combined effects of genotype and gender on CP susceptibility were not observed for these two polymorphisms, there does seem to be increased risk of CP in males with allele A compared to females with allele A (rs3795391: P= 0.008; rs3806232: P= 0.009). Hence we found an important association between polymorphisms in the S100A8 gene and periodontitis in a Chinese population.

Immunolocalization of lactoferrin in healthy and inflamed gingival tissues

BACKGROUND

It has been reported that lactoferrin prevents biofilm formation and exerts antimicrobial activity. The aim of the present study was to evaluate the cellular source of lactoferrin in healthy and inflamed gingiva.

METHODS

Lactoferrin synthesis was examined in relation to disease manifestation in biopsies of the marginal gingiva by immunohistochemistry. The expression of lactoferrin in cell cultures was studied by immunocytochemistry and reverse transcription-polymerase chain reaction (RT-PCR).

RESULTS

Healthy gingiva demonstrated no immunoreactivity to lactoferrin in epithelial and connective tissue cells. In inflamed specimens, lactoferrin staining was related to inflammatory cells. These results were confirmed by cell cultures of keratinocytes that did not show any immunoreactivity against lactoferrin. No mRNA message for lactoferrin was detected by RT-PCR in keratinocytes.

CONCLUSIONS

These data provide evidence that lactoferrin is not synthesized in healthy gingival tissues. Therefore, elevated lactoferrin levels in the crevicular fluid of inflamed tissues originate from invading cells of the inflammatory reaction.

Gingival crevicular fluid levels of calprotectin and myeloperoxidase during therapy for generalized aggressive periodontitis

BACKGROUND

Levels of the inflammation marker calprotectin in gingival crevicular fluid correspond to clinical and biochemical parameters of periodontal inflammation. Neutrophil granulocytes (polymorphonuclear neutrophils: PMNs) are supposed to be the main source of calprotectin in gingival crevicular fluid, but evidence is still lacking. The influence of periodontal therapy on gingival crevicular fluid levels of calprotectin has not yet been determined.

OBJECTIVES

Gingival crevicular fluid levels of calprotectin were monitored during therapy for generalized aggressive periodontitis. Interrelations between calprotectin and the PMN marker myeloperoxidase (MPO) were evaluated.

MATERIAL AND METHODS

Gingival crevicular fluid samples were collected from 23 patients with generalized aggressive periodontitis before and 3 months after non-surgical therapy with an adjunctive antimicrobial medication. Clinical parameters were recorded with a pressure-calibrated electronic probe. Levels of calprotectin and MPO in gingival crevicular fluid were analysed by enzyme-linked immunosorbent assay (ELISA) procedures.

RESULTS

At baseline, levels of calprotectin and MPO were highly correlated. Bleeding and suppurating sites showed significantly higher levels of calprotectin and MPO than non-bleeding, non-suppurating sites. Therapy significantly decreased levels of both biomarkers. These changes of calprotectin and MPO were highly correlated and also related to probing-depth reduction. Three months after therapy, the levels of both markers still showed significant correlations in initially deep sites, whereas in initially shallow sites no significant correlation was found. After therapy, levels of markers in bleeding and non-bleeding sites were comparable.

CONCLUSION

The correlations between calprotectin and MPO indicate that PMNs are a major contributor to the calprotectin content in gingival crevicular fluid of severely affected sites. Calprotectin levels in gingival crevicular fluid and their changes reflect periodontal inflammation as well as the clinical treatment outcome. A prognostic potential of this marker substance remains to be determined.

Human beta-defensin (hBD-1, -2) expression in dental pulp

The purpose of this study was to investigate the expression of human beta-defensins (hBD-1, -2) in dental pulps by reverse-transcription polymerase chain reaction (RT-PCR) and immunohistochemistry. The mRNA transcripts of human beta-defensin-1 and human beta-defensin-2 could be detected by performing RT-PCR. With immunohistochemical staining of pulp tissue using antisera to hBD-1 and -2 it was possible to demonstrate cytoplasmic expression in odontoblasts. The results demonstrate that not only oral keratinocytes at the epithelial surface but also odontoblasts express human beta-defensins. Thus odontoblasts take part in the innate immune system and human beta-defensins may play an important role in the innate host defense of human dental pulp.

Myeloid-related protein (MRP)8/14 (calprotectin) and its subunits MRP8 and MRP14 in plaque-induced early gingival inflammation

BACKGROUND

The inflammatory myeloid-related protein, MRP8/14, also called calprotectin, and its subunits MRP8 and MRP14 have been detected and identified recently in gingival crevicular fluid (GCF). It has been suggested that the type and phase of inflammation can be discriminated on the basis of differences in the expression of calprotectin and its subunits, released during activation and/or death of granulocytes and monocytes. The purpose of this study was to quantify calprotectin and its subunits (MRPs) simultaneously in the GCF during the initial phase of experimentally induced gingivitis, and to examine their inter- and intra-individual variations.

MATERIAL AND METHODS

Fifteen healthy non-smoking subjects, aged 18-30, were involved in this study. An initial hygiene phase (days -11 to 0) was followed by 10 days of undisturbed plaque accumulation. At days -11, -3, 0, 10, 11, clinical parameters were recorded and GCF samples collected with Durapore strips from 12 sites in each subject. Quantitative analyses of total proteins, MRP8/14, MRP14 and MRP8 were performed by ELISA procedures.

RESULTS

During the experimental phase with no oral hygiene (days 0-10), the clinical parameters Plaque Index, Gingival Index (GI) and bleeding on probing increased as expected, confirming that plaque accumulation leads to gingival inflammation. Levels of the MRPs were individually variable. They increased with plaque accumulation in one-half of the subjects, and decreased in the other subjects. The levels of MRP8/14 and MRP14 at subject recruitment (day -11) could predict a significant part of the GI at day 10. Only minute amounts of the subunits MRP8 and MRP14 were detected in comparison with the complex MRP8/14 throughout the experiment. Considerable variations were noted among sites within subjects.

CONCLUSION

The expression of calprotectin in the early phase of experimental gingivitis is variable between subjects, and two groups of subjects can be differentiated according to their response patterns. Clinical parameters at the very first visit (day -11) seemed to be different in the two response groups. The results of the present investigation indicate that the inflammatory response to plaque accumulation depends on the initial status of the subjects, which may not be leveled out by the introduction of perfect oral hygiene. Whether these patterns reflect a different susceptibility to periodontal diseases remains to be determined.

Lactoferrin and other markers from gingival crevicular fluid and saliva before and after periodontal treatment

OBJECTIVES

The aim of the study was to verify (i) if crevicular fluid defence variables reflect the changes after surgical periodontal treatment and (ii) if they are in correspondence with changes of these variables in the unstimulated and stimulated whole saliva.

MATERIAL AND METHODS

For 12 male and 13 female volunteers with chronic periodontitis lactoferrin concentration as well as the lysozyme and peroxidase activities were determined in crevicular fluid as well as in unstimulated and stimulated saliva before and 14 days after surgical periodontal treatment by a minimal invasive flap technique.

RESULTS

The lactoferrin concentrations decreased significantly in the crevicular fluid eluting solution from 1.63 to 1.23 mg/l reflecting a decrease in the total amount collected, in unstimulated saliva from 10.54 to 8.96 mg/l, and in stimulated saliva from 9.00 to 7.11 mg/l after treatment. No significant change could be found for lysozyme. Peroxidase activity was significantly reduced from 269.06 to 186.15 U/l only in the crevicular fluid.

CONCLUSION

The results of this study suggest that (i) the defence factor lactoferrin is suitable for monitoring of periodontal treatment results and (ii) changes of the lactoferrin concentration in crevicular fluid are related with significant changes in unstimulated and stimulated saliva.

Induction of calprotectin release by Porphyromonasgingivalis lipopolysaccharide in human neutrophils

Calprotectin, a major cytosolic protein of leukocytes, is detected in neutrophils, monocytes/macrophages, and epithelial cells. This protein is known to be a marker for several inflammatory diseases and is detected in inflammatory gingival tissue with periodontal disease. Recently, we found that the calprotectin level in gingival crevicular fluid from periodontitis patients was significantly higher than that of healthy subjects. However, the regulation of calprotectin in periodontal disease is unclear. In the present study, we investigated the effect of lipopolysaccharides of periodontopathic bacteria on calprotectin release from human neutrophils. Neutrophils from healthy donors were treated with lipopolysaccharides from Porphyromonas gingivalis (P-LPS), Actinobacillus actinomycetemcomitans, Prevotella intermedia, Fusobacterium nucleatum, and Escherichia coli. Calprotectin of neutrophil was identified by immunoblotting and calprotectin amount was determined by ELISA. Two subunits (10 and 14 kDa) of calprotectin were observed in the cell and medium fractions from neutrophils. P-LPS increased calprotectin release from seven to 16 times the control level after 30 min and its effect appeared in a dose-dependent manner (10-1000 ng/ml). Lipopolysaccharides from A. actinomycetemcomitans, P. intermedia, F. nucleatum, and E. coli also induced calprotectin release from neutrophils. These results suggest that lipopolysaccharides from periodontopathic bacteria induce calprotectin release from human neutrophils.

Zinc, Iron, Copper, Selenium, Lactoferrin, and Ferritin in Human Pus

BACKGROUND

Restriction of zinc and iron available for microbial growth in tissues are well-recognized host defense mechanisms. The present studies were performed to characterize some constituents of human pus that may affect these important host defenses.

METHODS

Zinc, iron, copper, calcium, and magnesium in pus were measured using an atomic absorption spectrophotometer; selenium was measured fluorometrically. Ferritin was measured with a fluorometric enzyme immunoassay, and lactoferrin was measured with a radial diffusion assay. The growth of Escherichia coli at 37 degrees C was measured in pus supernate adjusted to pH 5.5 or 7.4, in boiled supernate, or in supernate adjusted with 1.3 mM iron or 0.9 mM zinc singly or together.

RESULTS

Zinc and iron concentrations in pus exceeded normal serum. Calcium and magnesium levels were 2- to 3-fold lower and higher, respectively, than normal serum values. Lactoferrin concentrations of were 880 +/- 48 microg/mL and ferritin levels were 20,726 +/- 2,667 ng/mL. Growth of an E coli strain was inhibited in pus at pH 5.5 but not at pH 7.4, and growth was enhanced by addition of iron or zinc to E coli suspended in pus at pH 6.7.

CONCLUSIONS

To our knowledge, this is the first report of the zinc, iron, copper, selenium, lactoferrin, and ferritin levels of human pus. These studies provide additional insight into host defense mechanisms mediated by the restriction of the bioavailability of zinc and iron in suppurative infection.

Calprotectin (S100A8/S100A9), an inflammatory protein complex from neutrophils with a broad apoptosis-inducing activity

Calprotectin, a complex of two calcium-binding proteins that belong to the S100 protein family, is abundant in the cytosolic fraction of neutrophils. A high level of calprotectin reportedly exists in extracellular fluid during various inflammatory conditions, such as rheumatoid arthritis, cystic fibrosis and abscesses. However, the exact biological role(s) of the factor is now under investigation. We recently observed that neutrophils contain a factor that shows growth-inhibitory and apoptosis-inducing activities against various cell types including tumor cells and normal fibroblasts, and we identified that factor as calprotectin. The findings suggest that calprotectin exerts a regulatory activity in inflammatory processes through its effect on the survival or growth states of cells participating in the inflammatory reaction. It is also possible that calprotectin, at a high concentration, might have a deleterious effect on fibroblasts and influence the recovery of inflammatory tissue. Therefore, the protein factor may be a new drug target to control inflammatory reactions. We found that a few of the Amaryllidaceae alkaloids effectively inhibited the growth-inhibitory and apoptosis-inducing activities of calprotectin. In this article, we focus on the biological functions of calprotectin in extracellular fluids, focusing on its apoptosis-inducing activity.

The novel human beta-defensin-3 is widely expressed in oral tissues

The purpose of this study was to investigate the expression of human beta-defensins (hBD), especially of the recently discovered hBD-3, in oral tissues by reverse-transcription polymerase chain reaction (RT-PCR). Primary oral keratinocytes (n = 3) and fibroblasts (n = 3), 64 non-inflamed and 40 inflamed oral tissue samples, and 10 samples of salivary glands, were examined. The transcripts for hBD-3 (61/64), as well as for hBD-1 (64/64) and hBD-2 (54/64), were found to be widely expressed in non-inflamed oral tissues. In contrast, only 23, 22 and 24 of the 40 inflamed tissues showed detectable hBD-1, -2 and -3 transcripts, respectively. In salivary glands, mRNA expression was constitutive for hBD-1, frequent for hBD-2 (9/10), and infrequent for hBD-3 (4/10). Oral keratinocytes, but not fibroblasts, contained transcripts for all beta-defensins, suggesting that the novel hBD-3 is also produced in the epithelial compartment of oral tissues. The results indicate an important role for the novel hBD-3, as well as for hBD-1 and hBD-2, in the innate oral epithelial host defense.

The association of calprotectin level in gingival crevicular fluid with gingival index and the activities of collagenase and aspartate aminotransferase in adult periodontitis patients

BACKGROUND

Calprotectin, a major cytosol protein of leukocytes, exists in plasma and other body fluids of healthy human subjects. Since the calprotectin concentration rises markedly in some inflammatory diseases including rheumatoid arthritis, this protein has been thought to be a marker of inflammatory disease. Recently, we identified calprotectin in human dental calculus and gingival crevicular fluid (GCF), and found that the calprotectin concentration in GCF from patients with periodontitis was significantly higher than that in GCF from healthy subjects. In the present study, the association of GCF calprotectin level with GCF volume, gingival index (GI), and levels of biochemical markers including collagenase and aspartate aminotransferase (AST) in GCF was investigated to clarify the relationship between GCF calprotectin level and periodontal inflammation.

METHODS

Ninety GCF samples collected from periodontal pockets with a probing depth of more than 4 mm in 54 patients with adult periodontitis were used for these assays. The GCF volume was measured, and GI in each site was recorded. The calprotectin content in GCF samples was determined by ELISA using a specific antibody. The activity of collagenase or AST was measured by a respective assay kit.

RESULTS

The total amount of calprotectin and GCF volume showed a highly significant correlation (r = 0.64, P <0.0001), whereas the calprotectin concentration had no correlation with the GCF volume (r = 0.01, P= 0.924). The mean calprotectin concentration in GCF increased with the degree of GI, and the concentration in individual samples was significantly correlated with the GI score (r = 0.56, P<0.0001). Significant positive correlations were observed in GCF calprotectin versus collagenase (r = 0.57, P <0.0001) and GCF calprotectin versus AST levels (r = 0.40, P <0.005).

CONCLUSIONS

From the present results and our previous findings, it is shown that the GCF calprotectin level significantly correlates not only with clinical indicators but also with current biochemical marker levels and that calprotectin may be a useful marker for periodontal inflammation.

Human gingival crevicular fluid contains MRP8 (S100A8) and MRP14 (S100A9), two calcium-binding proteins of the S100 family

Human gingival crevicular fluid contains unidentified proteins which might play a role as markers in periodontal diseases. Therefore, low-molecular-weight proteins found in human gingival crevicular fluid (GCF), but absent from serum, were identified in the present study by means of two-dimensional electrophoresis (2-D PAGE) analysis. GCF, serum, and whole saliva were collected from periodontitis and healthy subjects, as well as from edentulous and newborn subjects. Protein samples were separated by two-dimensional polyacrylamide gel electrophoresis, stained with silver, and compared with reference protein maps in the SWISS-2D PAGE database. In GCF and saliva from periodontitis patients and healthy subjects, four dominant low-molecular-mass (from 8 to 14 kDa) acidic spots were observed. They were not found in serum and were less visible in saliva from edentulous and newborn subjects. From N-terminal amino acid sequencing, the two 2-D protein spots of 8 kDa and isoelectric points between 6.5 and 7.0 were both identified as protein MRP8 (SI00A8), a member of the S100 family of calcium-binding proteins. Using peptide mass fingerprinting and matrix-assisted laser desorption ionization time of flight mass spectrometry (MALDI-TOF-MS), we identified the other two protein spots, with mass of 14 kDa and isoelectric points between 5.5 and 6.0, as protein MRP14 (S100A9), also belonging to the S100 family. The presence of MRP8 and MRP14 in GCF was confirmed by Western blot, with monoclonal antibodies. The two polypeptides, MRP8 and MRP14, identified in GCF represent the major difference between the 2-D PAGE patterns of serum and GCF, and we hypothesize that they may play an important role in the gingival sulcus and could represent possible markers for periodontal diseases.