Calorie restriction-induced leptin reduction and T-lymphocyte activation in blood and adipose tissue in men with overweight and obesity.

BACKGROUND: T-Lymphocyte activation is modulated by the adipokine leptin and serum concentrations of this hormone can be reduced with short-term calorie restriction. The aim of this study was to understand whether leptin per se is important in determining levels of T-lymphocyte activation in humans, by investigating whether the reduction in leptin concentration following calorie restriction is associated with a decrease in T-Lymphocyte activation in blood and adipose tissue. METHODS: Twelve men with overweight and obesity (age 35-55 years, waist circumference 95-115 cm) reduced their calorie intake by 50% for 3 consecutive days. Blood and subcutaneous adipose tissue were obtained for isolation of immune cells and cytokine analysis. CD4+ and CD8 + T-Lymphocytes were identified and characterised according to their expression of activation markers CD25 and CD69 by flow cytometry. RESULTS: Serum leptin was reduced by (mean ± SEM) 31 ± 16% (p < 0.001) following calorie restriction. The percentage of blood CD4 + CD25 + T-lymphocytes and level of CD25 expression on these lymphocytes were significantly reduced by 8 ± 10% (p = 0.016) and 8 ± 4% (p = 0.058), respectively. After calorie restriction, ex vivo leptin secretion from abdominal subcutaneous adipose tissue explants was not changed, and this corresponded with a lack of change in adipose tissue resident T-Lymphocyte activation. CONCLUSIONS: Serum leptin was reduced after calorie restriction and this was temporally associated with a reduction in activation of blood CD4 + CD25 + T-Lymphocytes. In abdominal subcutaneous adipose tissue, however, leptin secretion was unaltered, and there were no observed changes in adipose resident T-Lymphocyte activation.

Reconsidering the role of nasolabial angle in premolar extraction decision-making: A case-series study.

OBJECTIVES: To evaluate the impact of changes in upper incisor inclination and position on the alteration of the nasolabial angle (NLA) in a series of cases involving the extraction of four first premolars. MATERIALS AND METHODS: The study included 41 patients who underwent orthodontic treatment with premolar extractions. The patients were divided into two groups based on their pretreatment NLA values: Group 1 (NLA ≤ 100°) and Group 2 (NLA > 100°). Measurements of NLA, U1.NA and U1-NA were obtained before and after treatment and U1-Ls pretreatment measure was registered. Statistical analyses were performed to compare the differences in NLA, U1.NA and U1-NA between the two groups and to evaluate the influence of these variables added to U1-Ls (T1) on NLA changes. RESULTS: The results showed that Group 1 exhibited significant changes in NLA, while Group 2 did not. However, both groups showed significant changes in U1.NA and U1-NA. In Group 1, 80% of the individuals presented an increase in NLA and 20% no changes. In Group 2, 10% presented a decrease, 57% no changes and 33% an increase in NLA values. Multiple linear regression analysis indicated that the group factor had a statistically significant influence on NLA variation. Additionally, in Group 2, a negative correlation was observed between changes in U1.NA and NLA. CONCLUSIONS: The findings suggest that individuals with higher pretreatment NLA values tend to maintain their NLA values even after the correction of upper incisor inclination.

Malocclusion or laterorhinia: Which one impacts aesthetic facial perception the most?

INTRODUCTION: This study aimed to evaluate the perception of facial attractiveness when nose and teeth, together or isolated, present different degrees of disharmony. The secondary objective was to compare the perception of laypersons with that of dentists. MATERIALS AND METHODS: This cross-sectional observational study included 112 individuals (58 laypersons and 54 dentists) that evaluated 6 manipulated images of the face of the same model, scoring their attractiveness using 10 cm Visual Analogue Scales (VAS), with least and most attractive at the left and right anchors, respectively. The images contained manipulations performed only on the nose (laterorhinia) and mouth (misaligned teeth), as follows: (1) standard photograph, with symmetrical nose + aligned teeth; (2) 2 mm nasal deviation + aligned teeth; (3) 4 mm nasal deviation + aligned teeth; (4) symmetrical nose + misaligned teeth; (5) 2 mm nasal deviation + misaligned teeth and (6) 4 mm nasal deviation + misaligned teeth. We used the repeated measures ANOVA test and Tukey's post-test for intra-group comparison of the images. The independent t-test was used for inter-group comparison of each image. RESULTS: In the laypersons' group, the highest grades were given to images with aligned teeth and the lowest to misaligned teeth (smallest mean difference = 2.88 cm). For this group, there was no statistically significant difference (P-values ranged from .988 to 1.000) between scores of the three images in which teeth were aligned (range of 7.70-7.78 cm). In the group of dentists, highest grades were given to images with aligned teeth and the lowest to misaligned teeth. Difference between images 3 and 4 was not statistically significant (P = .204). All other differences between any image of straight teeth and any image with misaligned teeth were significant and the smallest mean difference between the two groups of images was 1.87 (P = .039). However, in the images with aligned teeth, there was also a statistically significant difference with higher scores to the images with symmetrical nose in contrast with those with significant laterorhinia (mean difference = 1.03 cm). CONCLUSION: Teeth disharmonies had a more negative impact on the aesthetic perception of the face than did nose deviations, for both dentists and laypersons.

LINE-1 Cargo and Reverse Transcriptase Activity Profiles in Extracellular Vesicles from Lung Cancer Cells and Human Plasma.

Long Interspersed Element-1 (LINE-1) is an oncogenic human retrotransposon that 'copies and pastes' DNA into new locations via reverse transcription. Given that enzymatically active LINE-1 can be exported in extracellular vesicles (EVs), and that LINE-1 mRNA and its two encoded proteins, ORF1p and ORF2p, are required for retrotransposition, the present study examined LINE-1 EV loading patterns relative to reverse transcriptase (RT) activity in vivo and in vitro. Density gradient ultracentrifugation identified conserved patterns of LINE-1 mRNA and protein distribution in EVs, with RT activity readily detected in EV fractions containing both LINE-1 mRNA and protein. Unlike whole cell and tissue lysates, the ORF1p in EVs was detected as a dimer. EVs from ostensibly healthy plasma donors showed variable but consistent ORF1p profiles, with residual levels of LINE-1 mRNA measured in some but not all samples. EVs from cancer cell lines had elevated mean LINE-1 levels and 5-85 times greater RT activity than EVs from normal cells or healthy plasma. EV RT activity was associated with EV LINE-1 mRNA content and was highest in cell lines that also expressed an elevated expression of ORF1p and ORF2p. Given that LINE-1 activation is a hallmark of many cancer types, our findings suggest that an EV LINE-1 'liquid biopsy' may be developed to monitor LINE-1 activity during the course of malignant progression.

Orthodontic treatment in the presence of aggressive periodontitis.

INTRODUCTION: Aggressive periodontitis causes periodontal destruction, with loss of supporting alveolar bone. The common symptom is rapid attachment loss in the first molar and incisor area, in young adults. OBJECTIVE: The aim of this study was to discuss the challenges, implications and the impact of orthodontic treatment in patients affected by severe periodontal problems, specifically aggressive periodontitis. DISCUSSION: In addition to other bacteria, the main pathogen involved in aggressive periodontitis is the Aggregatibacter actinomycetemcomitans. However, the susceptibility to the disease differs among individuals, being immune deficiencies the main reason for this variability. Many orthodontists are not comfortable about performing treatments on individuals with aggressive periodontitis. CONCLUSION: Orthodontic treatment is feasible in young patients with severe and localized aggressive periodontitis, as long as the limitations imposed by the disease are respected. An interdisciplinary approach is required, with frequent periodontal follow-up before, during and after orthodontic treatment, allowing the correction of dental positions without aggravating bone loss.

Influence of canine vertical position on smile esthetic perceptions by orthodontists and laypersons.

INTRODUCTION: Our objectives were to verify the impact of alterations in the vertical position of the maxillary canines in smile esthetic perceptions and to determine whether exposure of the gingival margins directly affects laypersons' and orthodontists' perceptions. METHODS: A smile photograph of a male subject showing gingival zeniths was selected, and the canine vertical positions were symmetrically modified in increments of 0.5 mm, creating 4 new images varying from 1.0 mm of intrusion to 1.0 mm of extrusion, with and without gingival exposure. The total of 10 images were evaluated by 60 orthodontists and 60 laypersons, who determined the level of attractiveness of each smile on a visual analog scale. RESULTS: For both orthodontists and laypersons, the canine vertical position modifications had a statistically significant influence (P <0.0001), and the gingival exposure had no significant influence on the smile esthetic evaluations. CONCLUSIONS: For both groups of evaluators, the most attractive smiles were the standard smile and the smiles with 0.5 mm of intrusion. The less attractive smiles were those with 1.0 mm of extrusion and 1.0 mm of intrusion. Orthodontists were more critical in their assessments. There were no differences in the esthetic evaluations of smiles with and without gingival margin exposure for both groups of evaluators.

Craniomaxillofacial morphology alterations in children, adolescents and adults with neurofibromatosis 1: A cone beam computed tomography analysis of a Brazilian sample

Background: Oral manifestations are common in neurofibromatosis 1 (NF1), and include jaws and teeth alterations. Our aim was to investigate the craniomaxillofacial morphology of Brazilian children, adolescents and adults with NF1 using cone beam computed tomography. Material and Methods: This study was conducted with 36 Brazilian individuals with NF1 with ages ranging from 4 to 75. The participants were submitted to anamnesis, extra and intraoral exam and cephalometric analysis using cone beam computed tomography. Height of the NF1 individuals was compared to the length of jaws and skull base. The results of the cephalometric measurements of the NF1 group were compared with a control group paired by age, gender and skin color. Results: Individuals with NF1 had lower maxillary length (p<0.0001), lower mandibular length (p<0.0001), lower skull base length (p<0.0001. In children and adolescents, the mandible was more posteriorly positioned (p=0.01), when compared with the control group. There was no association between jaws and skull base length with the height of the individuals with NF1. Conclusions: Brazilian children, adolescents and adults with NF1 have short mandible, maxilla and skull base. Moreover, children and adolescents present mandibular retrusion (AU)

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Orthodontic-surgical retreatment of facial asymmetry with occlusal cant and severe root resorption: A 3-year follow-up.

Our objective was to report the orthodontic and surgical retreatment of a patient who had undergone a prolonged orthodontic treatment with extractions, but who had unsatisfactory results and persistent side effects. The man, aged 25 years 3 months, sought treatment with major complaints of facial and smile asymmetries. The clinical examination showed a mandibular deviation to the right and a maxillary occlusal cant. A Class II Division 1 subdivision right was observed. Radiographic examination showed extensive root resorptions in the maxillary second premolars and absence of the 4 first premolars. The maxillary midline was deflected 2 mm to the left, and the mandibular midline was shifted 5 mm to the right. Aligning and leveling were performed with orthodontic fixed appliances, with a standard edgewise system (0.022 × 0.028 in), followed by LeFort I maxillary impaction and bilateral sagittal split osteotomy with asymmetrical advancement. Retreatment showed outstanding results that remained stable after 3 years of follow-up. Root resorption in the second premolars did not seem to increase. Orthodontic-surgical intervention is the main choice for correcting esthetic and functional problems in facial asymmetry, particularly in cases of retreatment.

Adipose tissue metabolic and inflammatory responses to a mixed meal in lean, overweight and obese men.

PURPOSE: Most of what we know about adipose tissue is restricted to observations derived after an overnight fast. However, humans spend the majority of waking hours in a postprandial (fed) state, and it is unclear whether increasing adiposity impacts adipose tissue responses to feeding. The aim of this research was to investigate postprandial responses in adipose tissue across varying degrees of adiposity. METHODS: Thirty males aged 35-55 years with waist circumference 81-118 cm were divided equally into groups categorized as either lean, overweight or obese. Participants consumed a meal and insulinaemic, glycaemic and lipidaemic responses were monitored over 6 h. Subcutaneous adipose tissue samples were obtained at baseline and after 6 h to examine changes in gene expression and adipose tissue secretion of various adipokines. RESULTS: Following consumption of the meal, insulin and glucose responses were higher with increased adiposity (total AUC effects of group; p = 0.058 and p = 0.027, respectively). At 6 h, significant time effects reflected increases in IL-6 (F = 14.7, p = 0.001) and MCP-1 (F = 10.7, p = 0.003) and reduction in IRS2 adipose tissue gene expression (F = 24.6, p < 0.001), all independent of adiposity. Ex vivo adipokine secretion from adipose tissue explants remained largely unchanged after feeding. CONCLUSIONS: Increased systemic measures of postprandial metabolism with greater adiposity do not translate into increased inflammatory responses within adipose tissue. Instead, postprandial adipose tissue changes may represent a normal response to feeding or a (relatively) normalized response with increased adiposity due to either similar net exposure (i.e. per g of adipose) or reduced adipose tissue responsiveness.

Morphological Simulation of Different Incisal Embrasures: Perception of Laypersons, Orthodontic Patients, General Dentists and Orthodontists.

OBJECTIVE: This study aimed to evaluate how different forms of incisal embrasures influence the esthetic perception of the smile, the preferences of each group of evaluators, and the influence of gingival display. MATERIAL AND METHODS: Two photographs of a broad male and female smiles were digitally manipulated to remove imperfections and asymmetries. A second manipulation was performed on the four maxillary incisors, creating 3 different forms of incisal embrasures: rounded, semi-rounded and squared. The lower region of the upper lip was shifted down to simulate a smile with and without gingival display, resulting in a total of 12 photos. A presentation in digital media was structured with instructions and the photos to be studied by 240 evaluators, who were divided into four groups: laypersons, patients undergoing orthodontic treatment, general dentists and orthodontists. The statistical analysis comprised the Multiple Factor ANOVA (SPANOVA), and the Tukey's post-test was applied at a 5% significance level. RESULTS: The semi-rounded form was generally preferred, with a score of 70.83 for the male smile, and 77.26 for the female smile. Gingival display generated a statistically significant influence on how the embrasures were perceived, with the semi-rounded being preferred when associated with gingival display. Orthodontists were the most stringent in their evaluations. Patients and laypersons exhibited different patterns of esthetic perception. CONCLUSIONS: The form of the incisal embrasures associated with gingival display influenced the evaluators' esthetic perception. There was a statistically significant difference between the groups of patients and orthodontists. CLINICAL SIGNIFICANCE: Incisal embrasures play an important role in smile esthetics and influence the attractiveness perception. In general, the semi-rounded embrasure form is the most preferred. Different groups' perceptions on tooth morphology reinforce the importance of patient participation in treatment planning. (J Esthet Restor Dent 29:68-78, 2017).

Variations between maxillary central and lateral incisal edges and smile attractiveness.

INTRODUCTION: In this study, we aimed to verify whether different levels of maxillary incisal edges influence the perception of smile attractiveness and whether gingival display affects this perception according to groups of orthodontists, dentists, orthodontic patients, and laypersons. METHODS: Photographs of the smiles of 1 man and 1 woman showing the gingival contours of the incisors and the canines were digitally altered, creating steps from 0 to 2.0 mm in 0.5-mm increments, with and without gingival exposure. The 20 pictures were shown in random order to 240 evaluators divided into 4 groups who were asked to provide attractiveness scores on visual analog scales. RESULTS: Both the steps (P <0.001) and the gingival exposure (P <0.05) had statistically significant influences on the evaluations in all groups. There was also a statistically significant difference (P <0.001) between the evaluations of orthodontists and the other groups, with distinct patterns. CONCLUSIONS: The most accepted vertical relationship of incisor borders was the 1.0-mm step. There were significant differences in the evaluation of orthodontists when compared with the other 3 groups, and no significant difference was detected between these groups. The gingival display altered significantly the esthetic perception of the smiles evaluated. There were significant differences between the evaluations of the smiles of the man and the woman.

An interview with Hyeon-Shik Hwang.

It gives me great pleasure to interview Dr. Hyeon-Shik Hwang, an innovative orthodontist who has developed many creative techniques over his career. Dr. Hwang was born in Korea and received his DDS and PhD degrees from Yonsei University in Seoul. He is professor and chairman of the Department of Orthodontics at Chonnam National University School of Dentistry, Gwangju, Korea. Dr. Hwang, as a faculty at the university hospital, has maintained a successful clinical practice for more than 25 years. He has treated many adult patients focusing on esthetics and periodontal health and has developed many clinical techniques to improve the effectiveness and efficiency of treatment to the benefit of both the patient and practitioner. Dr. Hwang is also interested in the evaluation of facial asymmetry two- and three-dimensionally. As one of the early adopters of cone-beam volume imaging, he has given special emphasis on the management of surgical cases. He is married to Jung-Un Park with whom he has two sons. His favorite hobbies are photography and listening to music. When I was presented to him in a congress, it was a great pleasure meeting someone who I already admired for his singular work. Later on, his humbleness and knowledge made me marvel at him even more. I hope that all readers of Dental Press Journal of Orthodontics also enjoy the teachings from this brilliant Korean orthodontist! Guilherme Thiesen - interview coordinator.

Avaliação in vitro do desempenho da alça ortodôntica em T / In vitro evaluation of the performance of orthodontic T-loops

O objetivo deste estudo foi avaliar em testes de tração os efeitos na relação carga/deflexão de alças de retração em T quando alterados na confecção o tipo de liga metálica (aço inoxidável ou titânio-molibdênio -TMA) e a altura (7 e 9 mm). Quarenta alças foram confeccionadas combinando os dois fios e as duas alturas, divididas em 4 grupos (10 alças por grupo), mantendo-se uma dimensão horizontal de 10 mm. Os testes foram realizados em máquina para ensaios de tração com célula de carga, onde as alças de cada grupo sofreram ativações a partir de 1 mm até 3 milímetros, com intervalos de 0,5 mm. Os resultados mostraram que tanto a variação da liga quanto da altura da alça produziram variação significativa na relação carga/deflexão. Foi feita uma comparação entre os níveis de força encontrados em cada uma das situações testadas e os valores recomendados na literatura científica para retração dos dentes anteriores. Foi observado que para 1,0 mm de ativação, apenas as alças de aço com 7 mm de altura atingiram os níveis de força recomendados. Para as ativações de 1,5 e 2,0 mm, tanto as alças de aço de 9 mm quanto as alças de TMA com 7 mm atingiram tais valores. Para as ativações de 2,5 e 3,0 mm, apenas as alças de TMA com 9 mm de altura foram consideradas seguras, uma vez que todas as demais produziram forças demasiadamente altas para o uso clínico...

The aim of this study was to evaluate, in traction test, the effects on the load/deflection rate of the T-loop, when changing the type of alloy used in its confection (stainless steel-SS -or Titanium-Molybdenum alloy - TMA), and the height of the loop (7 and 9 millimeters). Forty loops were bent combining the two alloys and the two heights, divided in four groups of 10 loops each. The horizontal dimension was kept in 10 mm. The tests were made in a traction test machine with a load cell, where the loops from each group were activated from 1 to 3mm in steps of 0.5mm. Results showed that both the variation of the alloy and the variation of the height produce significant changes in the load/deflection rate. A comparison was made between the forces found in each of the situations tested and the numbers suggested in the scientific literature for anterior retraction, and it was observed that, for activations of 1mm, only the SS 7mm high loops reached the levels recommended. For activations of 1.5 and 2.0mm, both the loops made of SS 9mm high and the ones made of TMA 7mm high delivered the necessary force. For activations of 2.5 and 3.0 mm, only the TMA loops 9mm high were considered safe for clinical use, since all the other loops delivered excessive force...

Reliability and reproducibility of three-dimensional cephalometric landmarks using CBCT: a systematic review.

OBJECTIVE: The aim of this study was to review the reliability and reproducibility of 3D-CBCT (cone beam computed tomography) cephalometric landmark identification. METHODS: Electronic databases (Pubmed, Scopus, Web of Science) were searched for papers published from 1998 to October 2014. Specific strategies were developed for each database, with the guidance of a librarian. Two reviewers independently analyzed the titles and abstracts for inclusion. The articles that met the inclusion and exclusion criteria were selected for full-text reading, and the selected articles went through methodological quality evaluation. After the exclusion of repeated articles, the titles of the remaining ones were read and 1,328 of them were excluded. The abstracts of 173 articles were read, of which 43 were selected, read in full and submitted to the inclusion and exclusion criteria. Fourteen articles or studies with reliable methodology and reproducibility remained. The data were collected, organized into figures and analyzed for determination of the reliability and reproducibility of the three-dimensional cephalometric landmarks. RESULTS: Overall, the landmarks on the median sagittal line and dental landmarks had the highest reliability, while the landmarks on the condyle, porion and the orbitale presented lower levels of reliability. Point S must be marked in the multiplanar views associated with visualization in 3D reconstruction. Further studies are necessary for evaluating soft tissue landmarks.

Reliability and reproducibility of three-dimensional cephalometric landmarks using CBCT: a systematic review

Objective : The aim of this study was to review the reliability and reproducibility of 3D-CBCT (cone beam computed tomography) cephalometric landmark identification. Methods : Electronic databases (Pubmed, Scopus, Web of Science) were searched for papers published from 1998 to October 2014. Specific strategies were developed for each database, with the guidance of a librarian. Two reviewers independently analyzed the titles and abstracts for inclusion. The articles that met the inclusion and exclusion criteria were selected for full-text reading, and the selected articles went through methodological quality evaluation. After the exclusion of repeated articles, the titles of the remaining ones were read and 1,328 of them were excluded. The abstracts of 173 articles were read, of which 43 were selected, read in full and submitted to the inclusion and exclusion criteria. Fourteen articles or studies with reliable methodology and reproducibility remained. The data were collected, organized into figures and analyzed for determination of the reliability and reproducibility of the three-dimensional cephalometric landmarks. Results : Overall, the landmarks on the median sagittal line and dental landmarks had the highest reliability, while the landmarks on the condyle, porion and the orbitale presented lower levels of reliability. Point S must be marked in the multiplanar views associated with visualization in 3D reconstruction. Further studies are necessary for evaluating soft tissue landmarks. .

Evaluation of cephalometric landmark identification on CBCT multiplanar and 3D reconstructions.

OBJECTIVE: To evaluate the reliability of three-dimensional (3D) landmark identification in cone-beam computed tomography (CBCT) using two different visualization techniques. MATERIALS AND METHODS: Twelve CBCT images were randomly selected. Three observers independently repeated three times the identification of 30 landmarks using 3D reconstructions and 28 landmarks using multiplanar views. The values of the coordinates X, Y, and Z of each point were obtained and the intraclass correlation coefficient (ICC) was calculated. RESULTS: The ICC of the 3D visualization was rated >0.90 in 67.76% and 45.56%, and ≤0.45 in 13.33% and 14.46% of the intraobserver and interobserver assessments, respectively. The ICC of the multiplanar visualization was rated >0.90 in 82.16% and 78.56% and ≤0.45 in only 16.7% and 8.33% of the intraobserver and interobserver assessments, respectively. An individual landmark classification was done according to ICC values. CONCLUSIONS: The frequency of highly reliable values was greater for multiplanar than 3D reconstructions. Overall, lower reliability was found for points on the condyle and higher reliability for those on the midsagittal plane. Depending on the anatomic region, the observer must choose the most reliable type of image visualization.

Compensatory orthodontic treatment for maxillary deficiency: a 4-year follow-up.

In this article, we report the orthodontic treatment of a boy (age 12 years 9 months) who had a midface deficiency, a concave facial profile with maxillary retrusion, a complete crossbite (anterior and posterior), and the maxillary right canine retained in the alveolus. Rapid maxillary expansion was performed followed by complete orthodontic treatment with fixed appliances combined with Class III elastics and anterior vertical elastics. Time was allowed to elapse until growth was virtually over before removing the fixed appliances (at age 18 years 4 months), and no retainer of any type was used. As a result of treatment, significant improvement was noted in his facial appearance, with a proper maxillomandibular relationship, total correction of the maxillary atresia, and satisfactory overjet and overbite. The results remained stable at the 4-year follow-up. Therefore, it can be argued that the use of Class III elastics combined with rapid maxillary expansion has a beneficial effect in the treatment of transverse and sagittal maxillary deficiency in growing patients. Excellence in how the treatment was finished and discontinuation of treatment and control in the final stages of growth contributed to the stability of the final results.

TLR-2 activation induces regulatory T cells and long-term suppression of asthma manifestations in mice.

Asthma is a chronic inflammatory disease of the airways characterized by variable airway obstruction and airway hyperresponsiveness (AHR). The T regulatory (Treg) cell subset is critically important for the regulation of immune responses. Adoptive transfer of Treg cells has been shown to be sufficient for the suppression of airway inflammation in experimental allergic asthma. Intervention strategies aimed at expanding the Treg cell population locally in the airways of sensitized individuals are therefore of high interest as a potential therapeutic treatment for allergic airway disease. Here, we aim to test whether long-term suppression of asthma manifestations can be achieved by locally expanding the Treg cell subset via intranasal administration of a TLR-2 agonist. To model therapeutic intervention aimed at expanding the endogenous Treg population in a sensitized host, we challenged OVA-sensitized mice by OVA inhalation with concomitant intranasal instillation of the TLR-2 agonist Pam3Cys, followed by an additional series of OVA challenges. Pam3Cys treatment induced an acute but transient aggravation of asthma manifestations, followed by a reduction or loss of AHR to methacholine, depending on the time between Pam3Cys treatment and OVA challenges. In addition, Pam3Cys-treatment induced significant reductions of eosinophils and increased numbers of Treg cells in the lung infiltrates. Our data show that, despite having adverse acute effects, TLR2 agonist treatment as a therapeutic intervention induces an expansion of the Treg cell population in the lungs and results in long-term protection against manifestation of allergic asthma upon subsequent allergen provocation. Our data indicate that local expansion of Tregs in allergic airway disease is an interesting therapeutic approach that warrants further investigation.