PubMed Health⌕ Search

Biomedical subjects

J M Wilton

Publications and source records attributed to J M Wilton.

At least 19 recordsLinked to original sources

Neutrophils die in the gingival crevice, periodontal pocket, and oral cavity by necrosis and not apoptosis.

BACKGROUND: Neutrophils play important roles in the homeostasis of periodontal tissues. However, remarkably little is known about how these cells live and die in the gingival crevice and periodontal pocket. We have examined whether subgingival neutrophils die by necrosis or apoptosis and have begun to study the mechanisms controlling the functional lifespan of these cells. METHODS: Neutrophils collected from clinically healthy gingival crevices, periodontal pockets, and the oral cavity (saliva) were examined with Hoechst dye 33342, propidium iodide/eithidium bromide, and FITC-annexin V to identify live, dead, and apoptotic cells. Blood neutrophils were cultured for 17 to 20 hours in the presence or absence of gingival crevice washings (GC-w) to study the effect of GC-w on neutrophil apoptosis. In addition, endotoxin was removed from GC-w by affinity resin to investigate the contribution of LPS to the inhibitory effect of GC-w on blood neutrophils. RESULTS: The percentage of dead neutrophils in all subgingival sites and in all oral samples far exceeded the percentage of apoptotic neutrophils. In all 3 locations, approximately 30% of neutrophils were dead, whereas less than 1% of neutrophils were apoptotic. We conclude that the majority of neutrophils which lose their viability within gingival crevices, periodontal pockets and the oral cavity die by necrosis and not by apoptosis. Washings obtained from clinically healthy gingival crevices (GC-w) variably, but significantly, delayed apoptosis of peripheral blood neutrophils (mean suppression 45.7% +/- SD 22.3). Removal of endotoxin from GC-w significantly reduced this inhibitory effect. CONCLUSIONS: Our findings provide insights into the mechanisms of neutrophil death and the control of the functional lifespan of neutrophils in gingival crevices and periodontal pockets and therefore into the pathogenesis of periodontal diseases.

Adult↗

Permeability of the gingival tissues to IgM during an experimental gingivitis study in man.

Changes in the permeability of the underlying vasculature of the gingival crevice region may occur either as part of an inflammatory response during gingivitis or as a response to trauma during collection of gingival crevicular fluid IgM was selected as a marker of permeability and the concentration in gingival crevicular fluid was determined immunochemically by dot blotting, using rabbit antihuman IgM specific for mu chain. Gingival crevicular fluid samples were derived from experimental (non-cleaning) and control (cleaning) sites in six individuals participating in a 28-day experimental gingivitis study using a split-mouth protocol. The fluid was collected by a filter-paper method. At each site, four gingival crevicular fluid samples were collected for 5 s each over a 3-min period and a fifth sample was collected after a further 6 min. IgM was detected in 7/30 experimental strips at baseline (after intensive professional prophylaxis) and this increased to 21/30 by 24 days: control values were 13/30 and 12/30, respectively. The data indicate that IgM was detected with greater frequency as gingivitis becomes evident, suggesting increased permeability in response to plaque accumulation. IgM was detected in 17/120 of the first strip samples, collected over the 66-day study period, whereas in the fifth strip samples IgM was detected in 68/120, and the concentration of IgM in gingival crevicular fluid also increased, indicating that sequential collection induced permeability. It is concluded that the permeability of the gingiva changes in response to both an inflammatory stimulus and trauma due to collection.

Adult↗

Leukocyte activation and function-associated antigens in inflammatory disease.

Expression of adhesion molecules, CD11a, CD11b and CD18, and of the function-associated molecules CD3, CD4, CD8, CD16, CD19, CD56 and CD57 was assayed on peripheral blood leukocytes from normal control subjects (n = 10), and from patients with adult periodontitis PD (n = 9), ankylosing spondylitis AS (n = 11) and rheumatoid arthritis RA (n = 14). A novel rapid fixation leukocyte preparation technique was used which prevents artefactual up-regulation of surface antigens. In RA patients, the percentage of CD18+ lymphocytes was decreased and that of CD11b+ neutrophils was increased. On lymphocytes the mean fluorescence intensity (MFI) of both CD11b and CD18 was decreased whereas that of CD57 was increased. In AS patients the percentages of CD11b+ lymphocytes and neutrophils were increased and CD18+ lymphocytes and neutrophils were decreased. On lymphocytes the MFIs of CD11b and CD18 were decreased, whilst that of CD16 was increased. On neutrophils the MFI for CD18 was increased. No significant differences (p < 0.01) were seen for the periodontitis patients. It is suggested that the antigen expression on peripheral blood cells from RA and AS patients is consistent with leukocyte activation.

Antigens, Differentiation, T-Lymphocyte↗

Inhibition of polymorphonuclear leucocyte phagocytosis by Porphyromonas gingivalis culture products in patients with adult periodontitis.

Porphyromonas gingivalis culture products and a purified trypsin-like protease (TLPase) from the organism were tested for their effects on the phagocytosis of P. gingivalis by polymorphonuclear leucocytes (PMN) from 16 patients with adult periodontitis and 16 healthy subjects in a case-control study. Both the culture products (p < 0.0001) and the TLPase (p < 0.0001) significantly inhibited PMN phagocytosis by both case and control samples. Culture products were significantly more inhibitory in both cases (p < 0.0019) and controls (p < 0.0198) than that TLPase. The case PMNs were significantly more susceptible to inhibition by culture products than the control PMNs (p < 0.0238). The data suggest that patients with adult periodontitis have PMNs that are more susceptible than normal to the inhibitory effects of P. gingivalis and might be at greater risk than healthy subjects to infection by this pathogen.

Adult↗

Interleukin-1 beta and IgG subclass concentrations in gingival crevicular fluid from patients with adult periodontitis.

Interleukin-1 beta (IL-1 beta) and the four IgG subclasses were measured in gingival crevicular fluid (GCF) at 35 sites in 19 patients with adult periodontitis. Serum concentrations of the IgG subclasses were assayed in 16 patients. IL-1 beta was detected in GCF at 88.6% of sites at concentrations ranging from 12.38-420.90 pg/microliters (mean 138.35 +/- 112.61 pg/microliters). IgG1 was detected at 81.2% sites, IgG2 at 93.6%, IgG3 at 71% and IgG4 at 71%. Absolute concentrations in GCF were: IgG1--2.419 g/l +/- (SD) 3.389; IgG2--2.945 +/- 6.434; IgG3--0.118 +/- 0.144; IgG4 0.864 +/- 1.336. There were no significant correlations between IL-1 beta concentrations, GCF volume or the clinical status of the sample site. IL-1 beta was not correlated with any of the IgG subclasses. The absolute concentrations of all subclasses in GCF were significantly negatively correlated with GCF volume and positively correlated with the Bleeding Index. Only IgG4 was significantly negatively correlated with the probeable crevice depth index. The concentration of each IgG subclass was positively correlated with the other three IgG subclasses. Subclass concentrations in GCF, relative to serum concentrations, were not correlated with GCF volume or clinical status. Relative concentrations of IgG1, IgG2 and IgG3 showed significant positive correlation with each absolute concentration of the other subclasses but IgG4 did not show this relation. It was concluded that IL-1 beta is not related to clinical measurements of inflammation or previous attachment loss. The data suggest that IgG in GCF is largely derived from plasma but that some IgG4 may be locally synthesized.

Adult↗

Serum immunoglobulin G antibodies to Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum and Streptococcus sanguis during experimental gingivitis in young adults.

Twenty-eight young, healthy adults completed an experimental gingivitis study in which blood and clinical recordings were obtained at baseline; after a 4-week period of thorough oral hygiene; after a subsequent 3-week period of plaque accumulation; and after another 2 weeks of thorough oral hygiene. Serum immunoglobulin G antibodies against whole cells of Porphyromonas gingivalis, Prevotella intermedia, Fusobacterium nucleatum and Streptococcus sanguis were determined using enzyme-linked immunosorbent assay. Mean serum immunoglobulin G antibody levels to P. intermedia, F. nucleatum and S. sanguis remained essentially constant during the experiment, whereas the immunoglobulin G antibodies to P. gingivalis declined during the initial period of oral hygiene and the subsequent period of plaque accumulation to an average of 84.5% of the baseline value. This reduction could be attributed to the people who developed marked gingival inflammation during the period of plaque accumulation, indicating that the systemic host response may be associated with local tissue responses to variations in oral hygiene. These people were, however, also characterized by higher initial serum immunoglobulin G responses to P. gingivalis than people who developed less pronounced gingival inflammation during the experiment. The variability and individuality noted in the host response to potential pathogens have important implications for attempts to use such measures for establishing a diagnosis or prognosis for the individual patient.

Adult↗

Elevated opsonic activity for Porphyromonas (Bacteroides) gingivalis in serum from patients with a history of destructive periodontal disease. A case: control study.

We have measured the opsonic capacity of serum for the phagocytosis of Porphyromonas (Bacteroides) gingivalis by polymorphonuclear leucocytes (PMN) in 35 patients with a history of destructive periodontitis and 35 matched control subjects. The serum from cases, tested at concentrations of 8% and 0.8% opsonised P. gingivalis for phagocytosis by PMN to a level significantly greater than controls (p < 0.0001 and < 0.01 respectively). IgG antibody levels to P. gingivalis whole cells estimated by ELISA were also significantly higher in the cases (p < 0.0001). The IgG antibody levels correlated significantly with the opsonic capacity of the serum tested at 8% concentration in controls (r = 0.371, p = 0.03) but not in cases (r = 0.235, p = 0.17); in 0.8% serum, the opsonic capacity of the cases and controls were not significantly correlated. Elevated opsonisation by serum was a significant predictor that a subject was a case rather than a control, even after allowing for the effect of elevated IgG antibody in the cases. The data suggest that an elevated capacity of serum to opsonise P. gingivalis is a distinctive feature in patients with past destructive periodontal disease.

Adult↗

Contamination of human gingival crevicular fluid by plaque and saliva.

Dental plaque and saliva are both possible contaminants of gingival crevicular fluid (GCF). Plaque samples from 12 sites in four subjects who had allowed plaque to accumulate for 24-48 h were quantified using the Plaque Index and then transferred to filter paper strips for fluid volume determination using the Periotron 6000. The mean volume of fluid for plaque scores of 0 was 0.02 (+/- 0.01) microliter, whereas for plaque scores of 3 the mean volume was 0.15 (+/- 0.07) microliters. In a clinical study, GCF samples, from 19/184 subjects (10.4%) were assessed as contaminated or suspected to be contaminated with saliva, but only 28/1740 strips (1.6%) were placed in these categories of contamination. An assay to confirm salivary contamination was established, using an immunochemical, double-antibody method with sheep anti-human salivary alpha-amylase followed by peroxidase-conjugated rabbit anti-sheep immunoglobulin. The detection threshold of the assay was 7.5 ng of alpha-amylase, which represents approx. 15-25 nl of saliva. The assay was evaluated on 90 GCF samples categorized as 'known' (n = 16), 'suspected' (n = 16), or 'not' contaminated (n = 58) with saliva; 81.25, 50-61.5 and 5.2-8.6%, respectively, were positive for salivary alpha-amylase. In some GCF samples salivary contamination was in excess of 50%. It was concluded that GCF samples seen to be contaminated with saliva should be discarded, whereas samples considered free from contamination may be used with confidence. Samples suspected of contamination may require an alpha-amylase assay before further analysis.

Densitometry↗

Interaction and intracellular killing of Candida albicans blastospores by human polymorphonuclear leucocytes, monocytes and monocyte-derived macrophages in aerobic and anaerobic conditions.

Polymorphonuclear leucocytes (PMN), monocytes and monocyte-derived macrophages were capable of interacting with opsonized C. albicans in both aerobic and anaerobic conditions. Superoxide anion release by these cells was inhibited in anaerobic conditions while lysozyme release and phagocytosis were equally efficient in both aerobic and anaerobic conditions. All cell types tested were capable of intracellular killing of C. albicans and this appeared to be maximum at 6 h for monocytes and macrophages and 24 h for PMN. Monocytes killed the lowest number of organisms, 1 x 10(6), and the killing was similar for aerobic and anaerobic conditions. In contrast, PMN and macrophages demonstrated greater killing of C. albicans in aerobic conditions compared with anaerobic conditions; PMN killed 1.9 x 10(6) organisms and macrophages 3 x 10(6) when incubated anaerobically. Inhibitors of oxygen metabolism decreased intracellular killing of C. albicans by macrophages and PMN in aerobic but not anaerobic conditions. The oxygen reaction products involved in the killing of C. albicans appeared to be different however: macrophage killing was decreased by superoxide anion and hydrogen peroxide inhibitors. PMN killing was decreased by superoxide anion, hydrogen peroxide, hypochlorous acid and hydroxyl radical inhibitors. The present study shows that although monocytes, macrophages and PMN function similarly in their interaction with C. albicans, they appear to use different oxygen reactive products for the intracellular killing of C. albicans.

Adult↗

Elevated levels of the IgG2 subclass in serum from patients with a history of destructive periodontal disease. A case-control study.

The levels of the 4 subclasses of IgG were estimated in the serum from 35 patients with a history of chronic periodontitis and 35 matched controls. The levels of IgG2 were significantly (P less than 0.019) elevated in the patients (3.756 g l-1) compared to the controls (2.882 g l-1). The data suggest that the predominant antibody response to periodontal pathogens in periodontitis may be directed against carbohydrate or glycolipid antigens.

Adult↗

Interleukin-1 beta (IL-1 beta) levels in gingival crevicular fluid from adults with previous evidence of destructive periodontitis. A cross sectional study.

We have estimated the levels of Interleukin-1 beta (IL-1 beta) by ELISA in gingival crevicular fluid (GCF) at 58 sites from 37 patients with adult periodontitis. GCF was collected for 5 s on filter papers and a 2nd sample was collected for 30 s 1 min later. 68/116 strips yielded detectable levels of IL-1 beta. IL-1 beta was present in both the 1st and 2nd samples at 28 sites, in the 1st only at 4 sites and in the 2nd only at 8 sites; 18 sites were below the level of detection for the assay. When the concentrations of IL-1 beta were calculated in the original volume of GCF on each strip, the mean value for positive strips was 34.16 +/- 29.45 (SD) pg/microliters with a range from 1.75 to 97.13 pg/microliters. There were no statistically significant correlations with the plaque index, bleeding index or probable crevice depth (pocket depth). The results indicate that IL-1 is present in the GCF from a proportion of sites with evidence of previous periodontal destruction.

Adult↗

Associations between volume and flow rate of gingival crevicular fluid and clinical assessments of gingival inflammation in a population of British male adolescents.

Gingival crevicular fluid (GCF) sampling was performed on 2 occasions separated by 1 year, at 2 sites in the mouths of 102 male adolescents, mean age 17.85 years. Samples were collected onto 5 filter paper strips which were sequentially applied to the mouth of the crevice over a 9-min collection period. Volume and flow rates of GCF were determined for each site and were compared with clinical measurements of plaque, gingival colour, bleeding, gingival index (GI) and pocket depth, using a general linear models (GLM) procedure. While the initial volume of GCF showed no association with any clinical measurement, there was an association between flow rate of GCF and gingival colour. The volume of GCF collected in the final, 5th sample was associated with the GI. The sample site strongly influenced all measures of GCF volume. It is proposed that the flow rate of GCF may be a better indicator of gingival inflammation than the more imprecise clinical assessments of inflammation, since GCF flow rates more precisely reflect changes in tissue permeability. The association between the final sample, collected after 9 min, and clinical measurements, was probably a reflection of the association between clinically-detectable inflammation and the susceptibility of the site to mild irritation.

Adolescent↗

IgG subclass antibodies to Porphyromonas gingivalis in patients with destructive periodontal disease. A case: control study.

We have estimated by ELISA the levels of IgG subclass antibodies against P. gingivalis strain W83 whole cells in 35 cases of adult periodontitis and 35 age, sex, ethnic origin and plaque index-matched healthy controls. The mean levels of IgG1 (p < 0.0003) and IgG2 (p < 0.0416) were significantly elevated in the cases. Many sera had no detectable IgG4 antibodies but by categorising IgG4 responses into high, low and absent, this subclass was more often present (p < 0.002) in the cases. Analysis of the paired differences between cases and controls showed that only IgG1 (p < 0.0005) and IgG4 (p < 0.003) levels were significantly greater in the cases. The data support the role of P. gingivalis as a key pathogen in adult periodontitis and high levels of IgG4 antibodies might possibly provide a marker of patients with active disease.

Adult↗

Phagocytosis of Porphyromonas gingivalis and Prevotella intermedia by human polymorphonuclear leukocytes in clots formed from human plasma or purified fibrinogen.

We have studied the polymorphonuclear leukocyte (PMN) phagocytosis of Porphyromonas gingivalis (Bacteroides gingivalis) and Prevotella intermedia (Bacteroides intermedius) in three-dimensional fibrin meshworks formed by either clotting human plasma or by clotting purified fibrinogen with human serum incorporated. PMN phagocytosis of rhodamine isothiocyanate-labelled P. gingivalis in the fibrinogen clot was 43 +/- 6% and in the plasma clot was 62 +/- 10%; for P. intermedia the values were 15 +/- 10% and 63 +/- 10%, respectively. This showed that phagocytosis in the plasma clot system was significantly higher than in the fibrinogen clot system. However, increasing the concentration of serum in the fibrinogen clot abolished this difference, suggesting that opsonin levels determine PMN function in this assay. Labelling the bacteria with a different fluorochrome, fluoroscein isothiocyanate, reduced the level of PMN phagocytosis in both three-dimensional systems but phagocytosis was unaffected when PMN were adherent to glass. It would appear that PMN phagocytosis in three-dimensional systems can vary depending on the composition of the clot and the fluorochrome used to label the bacteria.

Analysis of Variance↗

Breastfeeding and the chemically dependent woman.

Chemical dependence in pregnant and postpartum women is an issue of concern for perinatal nurses. Special concerns arise when a chemically dependent woman chooses to breastfeed her infant. This article discusses the effects of the most common drugs of abuse on lactation and the neonate and criteria for and benefits of breastfeeding for this population.

Adult↗

Human junctional epithelium: demonstration of a new marker, its growth in vitro and characterization by lectin reactivity and keratin expression.

We have studied lectin reactivity in normal human junctional, sulcular, and attached gingival epithelia with 15 lectins and identified the epithelia by parallel staining with monoclonal anti-keratin antibodies. Dolichos biflorus agglutinin reacted uniquely with junctional epithelium, not staining other gingival cells of non-blood group A1 donors. We have demonstrated that the moiety recognized in junctional epithelium is not blood group A1 antigen or Tn antigen. Using a panning technique with this lectin to isolate the cells, we have grown keratinocytes from human junctional epithelium, and compared their phenotype in vitro to that of cells grown from the sulcular and attached gingival epithelium. Colonies established from each epithelial type were examined in frozen section with the anti-keratin antibodies. All expressed keratin 14 (keratinocyte marker), keratins 4 and 13 (suprabasal non-cornification markers), and keratins 7, 18, and 19 (simple epithelia keratins). Keratins 1, 10, and 8 were not expressed. Vimentin, the intermediate filament of mesenchymal cells, was also expressed by all types of cells in culture. Thus we have shown that when cells from the three areas of the gingiva were grown in culture they revert to one phenotype, at least with respect to their keratin expression. These results support the hypothesis that the epithelial phenotype is influenced by the sub-epithelial mesenchyme, and it is this that is responsible for the unique phenotype of the junctional epithelium.

ABO Blood-Group System↗

Specific antibody responses to subgingival plaque bacteria as aids to the diagnosis and prognosis of destructive periodontitis.

We have reviewed the recent literature on the humoral immune responses to a variety of subgingival plaque bacterial species in patients with destructive periodontal diseases. We do not feel that the information presently available on the specific antibody responses to proposed pathogens such as Bacteroides gingivalis and Actinobacillus actinomycetemcomitans allows antibody responses to be diagnostic. All control subjects without periodontal destruction have antibodies to candidate pathogens but the generally higher levels in patients are not sufficiently elevated to be diagnostic. Nor can they be used to predict the initiation of disease or the onset of new episodes of destruction where disease had previously occurred. Successful treatment of patients may lead to lower levels of antibodies to some organisms, including possible pathogens, and thus support a given species in the aetiopathogenesis of disease. It appears that unsuccessful treatment may be accompanied by continuing high antibody levels to some organisms and further studies may enable this observation to be used to monitor therapy. There is some evidence from serological studies that each destructive episode may be induced by a different bacterial species or consortium. The start of studies using single antigens and the techniques of molecular biology will provide not only antibody-based diagnostic methods but also allow us to determine which bacterial antigens are virulence factors and thus the role of the antibody responses, whether protective or damaging, in the periodontal diseases.

Actinobacillus↗