The Study Will Consist of Taking Some Samples of Crevicular Fluid (the Fluid Found in the Space Between the Gums and the Roots of the Teeth) to Assess a Particular Protein (LL-37) That Seems to be Related to the Immune Response Against Periodontal Disease (Gum Disease)
Keywords
Abstract
Description
'Antimicrobial peptide LL-37 as diagnostic biomarker in periodontal disease"
1. Introduction
Periodontal disease is an infectious process that consists of the destruction of the supporting anatomical structures of the tooth, as a consequence of the inflammatory response to the periopathogenic activity of the subgingival bacterial plaque, which leads to an innate, inflammatory and adaptative immune response.
The clinical manifestation of the disease depends of host and environmental factors as well as the specific microbiological agent involved. The interrelation amongst bacteria and the immunodefence mechanisms of the host constitute the base of the immunopathological mechanisms that lead to the disease. In healthy conditions, there is a balance between the activity of the periodontal microbiota and the host immune response.
In the innate defence system of the oral cavity there are several antimicrobial peptides involved, being one of them, the human cathelicidin LL-37.
The activity of antimicrobial peptides such as LL-37 in the gingival sulcus is considered one of the greatest defence mechanisms of the periodontum. The gingival epithelium not only constitutes a physical barrier to avoid bacterial invasion. Neutrophils migrate to the junctional epithelium and create a barrier between the bacterial plaque and the underlaying epithelium. They also produce antimicrobial peptides, one of them the 18 kDa (hCAP18). Once the neutrophils are activated in response to the bacterial aggression the release LL-37, with a similar activity to a broad-spectrum antibiotic.
The total absence of this peptide (LL-37) has been associated to aggressive periodontitis, in particular in patients with a neutrophil deficiency such as those who suffer Morfan Kosmann syndrome
The nature of this research aims to elucidate the role of LL-37 in periodontal disease by comparing the use of a none invasive technique such as crevicular fluid samples in patients that suffer periodontal disease, before and after receiving a course of basic periodontal treatment (root scaling and planing). Samples obtained will be analysed by immunohystochemical analysis (ELISA). The quantification of LL-37 before and after periodontal treatment associated with the clinical findings observed may serve as diagnostic biomarker of the immunopathological response inherent to the periodontal disease.
2. Justification of research question. Current status
Over the last years, a great effort by scientific community has been made in order to try to understand the complex immunopathological processes related to periodontal disease and the relationship between the activity of the periodontal microbiota and the host defence mechanisms.
The relevance of this research may serve to understand in more detail the role of the antimicrobial peptide LL-37 in periodontal disease not only due to their bactericidal effect but in the modulation of the immunological response of the host and its activity before and after periodontal treatment. The lack of studies on this matter reflects the need for further research on this topic.
Ultimately, the findings of this research may form the basis of a new therapeutic approach based on the use of LL-37 to help modulate the immunological response of the host in combination with conventional periodontal treatment. This may be particularly relevant in patients susceptible to develop periodontal or periimplant diseases or in particular cases that are resistant to conventional treatment alternatives.
3. Summary of intended research
The main aim of the study is to investigate the role of LL-37 in the immunopathological response of the periodontum. Subsequent aims are to investigate the possibility of using this microbial peptide to serve as diagnostic, prognostic as well as a therapeutic agent in the treatment of periodontal disease.
Research hypothesis: There are significant quantitative differences in the levels of LL-37 before and after periodontal treatment, with a significant reduction of LL-37 at re-evaluation (4-6 weeks after a course of basic periodontal treatment -root scaling and planing).
Null hypothesis: There are no significant quantitative differences in the levels of LL-37 before and after periodontal treatment
The objectives of the present study are:
1. Determine if healthy patients and patients with periodontal disease have different levels of LL-37 in saliva and crevicular fluid at baseline.
2. Evaluate if after a course of basic periodontal treatment, the levels of LL-37 in patients with periodontitis are similar to the quantified levels on healthy patients at baseline.
3. With respect to crevicular fluid samples, evaluate if the levels of LL-37 in teeth affected by periodontal disease differ from healthy sites on the same individual or if there are no significant differences in the above before and after a course of periodontal treatment.
4. Stablish a non-invasive protocol to evaluate the immunological state of the patient before and after periodontal treatment as prognostic factor.
4. Material and methods
Ethical approval from the Ethical Commite of University Rey Juan Carlos of Madrid (URJC) has been granted. A selection of patients of the "Master in Advanced Implantology, Tissue Regeneration and Implant supported prosthesis" of the FCU-URJC that fulfil the inclusion criteria and that consent to be part of the study will be made.
The inclusion criteria are the following:
- Medical history that does not contraindicate periodontal treatment
- The test group will consist of patients with periodontal disease (stage I-II, stage III-IV)
- The control group will consist of healthy individuals (probing depth 1-3mm, clinical signs of gingival health)
- All patients included in the study must give appropriate consent.
Exclusion criteria include the following:
- Patients that do not consent to be part of the study.
- Non controlled systemic diseases (ASA I, ASA II).
Smoker patients will not be excluded and will be classified as light smokers (less than 10 cigarettes/day) or heavy smokers (more than 10 cigarettes /day).
Diabetic patients will not be excluded either but will be identified and accounted for.
All patients included in the study will go through the following stages:
1. Complete periodontal examination (probing depth (PD), clinical attachment level (CAL), plaque index (PI), blood on probing (BOP)).
2. Patients will be divided in two groups:
- 30 healthy patients (control)
- 60 periodontal patients (test- periodontitis stage I-II (30 patients), periodontitis stage III- IV (30 patients).
Due to lack of in vivo studies, simple sample size calculation was made using a conservative power analysis (G*Power 3.1.9.4 program, 2009). The simple size (27 subjects) was based on a two-tailed test with an effective size of 0.05, an alphabetical error probability of 0.05, difference of 50% in mean value, standard deviations to be maxium 80% of the mean values and a power of 0.90.
Taking into account these parameters, a simple sample size between 21-30 patients per group is estimated.
Crevicular fluid samples will also be obtained following the manufacturers protocol using perio papers (Periopaper, Applied Biosystems, Inc, Foster City, CA). Teeth to be examined will be isolated with cotton rolls and air dried. Paper strips will be introduced into the gingival sulcus for approximately 30 seconds. Test group patients' samples will be taken from periodontally pathogenic sites and healthy sites. Heavily contaminated samples with saliva or blood will be discarded.
Samples will be stored at -80 C at the laboratory of Departamento de Epidemiología y Salud Pública, Edificio Departamental I, Fundación Clínica Universitaria, URJC (Alcorcon). Once all samples are obtained, appropriate transport will be arranged to the Department of Natural Sciences, Biomedical Sciences, Hendon Campus, Middlesex University of London. There ELISA analysis of all samples will be performed by using a specific ELISA kit commercially available for human LL-37 (HyCult Biotechnology, Uden, the Netherlands).
Patients of the test group will receive a course of basic periodontal treatment (root scaling and planing) and oral hygiene instructions after the first sample collection.
A re-evaluation appointment at 4-6 weeks will take place where new crevicular fluid samples of both groups will be obtained (test and control), to evaluate any statistically significant difference with respect to the quantity of LL-37 in relation to the baseline measurements recorded. After that, samples will be scrutinised again by performing ELISA assays following the protocol described above.
Once all results are obtained, statistical analysis of the samples will be carried out.
Dates
Last Verified: | 04/30/2020 |
First Submitted: | 05/16/2020 |
Estimated Enrollment Submitted: | 05/23/2020 |
First Posted: | 05/26/2020 |
Last Update Submitted: | 05/23/2020 |
Last Update Posted: | 05/26/2020 |
Actual Study Start Date: | 09/14/2020 |
Estimated Primary Completion Date: | 04/14/2021 |
Estimated Study Completion Date: | 06/14/2021 |
Condition or disease
Intervention/treatment
Diagnostic Test: Crevicular fluid analysis by using ELISA testing.
Phase
Arm Groups
Arm | Intervention/treatment |
---|---|
Healthy (control group) This group will include a total of 30 patients free of periodontitis Samples of crevicular fluid to quantity levels of antimicrobial peptide LL-37 will be taken at baseline
ELISA analysis of all samples will be performed by using a specific ELISA kit commercially available for human LL-37 (HyCult Biotechnology, Uden, the Netherlands). | |
Periodontitis (test group) 60 Periodontal patients (subdivided in 2 groups of 30, depending of the severity of their disease):
30 patients with Stage I-II periodontitis (mild/moderate)
30 patients with Stage III-IV periodontitis (severe).
Two sets of samples of crevicular fluid will be obtained before and after receiving a course of routine basic periodontal treatment (root scaling and planing).
A reevaluation visit to re-assess clinical periodontal parameters will take place at 4-6 weeks after treatment. New samples of crevicular fluid will then be taken at this stage to compare the level of LL-37 before and after the treatment.
ELISA analysis of all samples will be performed by using a specific ELISA kit commercially available for human LL-37 (HyCult Biotechnology, Uden, the Netherlands). |
Eligibility Criteria
Ages Eligible for Study | 18 Years To 18 Years |
Sexes Eligible for Study | All |
Sampling method | Non-Probability Sample |
Accepts Healthy Volunteers | Yes |
Criteria | Inclusion Criteria: - Medical history that does not contraindicate periodontal treatment - The test group will consist of patients with periodontal disease (stage I-II, stage III-IV) - The control group will consist of healthy individuals (probing depth 1-3mm, clinical signs of gingival health) - All patients included in the study must give appropriate consent. Smoker patients will not be excluded and will be classified as light smokers (less than 10 cigarettes/day) or heavy smokers (more than 10 cigarettes /day). Diabetic patients will not be excluded either but will be identified and accounted for. Exclusion Criteria: - Patients that do not consent to be part of the study. - Non controlled systemic diseases (ASA I, ASA II). |
Outcome
Primary Outcome Measures
1. LL-37 in crevicular fluid in healthy/periodontal patients. [At baseline for healthy (control) and periodontal (test) groups and at 4-6 weeks after treatment for test group]
Secondary Outcome Measures
1. Periodontal parameters [At baseline for healthy (control) and periodontal (test) groups and at 4-6 weeks after treatment for test group]
2. Probing depth (PD) [At baseline for healthy (control) and periodontal (test) groups and at 4-6 weeks after treatment for test group]
3. Clinical attachment level (CAL) [At baseline for healthy (control) and periodontal (test) groups and at 4-6 weeks after treatment for test group]
4. Plaque index (PI) [At baseline for healthy (control) and periodontal (test) groups and at 4-6 weeks after treatment for test group]
5. Blood on probing (BOP) [At baseline for healthy (control) and periodontal (test) groups and at 4-6 weeks after treatment for test group]