Tobias Fretwurst1,2,3, Carlos Garaicoa-Pazmino4,3, Katja Nelson2, William V Giannobile1, Cristiane H Squarize1,3, Lena Larsson1,5, Rogerio M Castilho1,3. 1. Department of Periodontics and Oral Medicine, University of Michigan School of Dentistry, Ann Arbor, MI, USA. 2. Department of Oral- and Maxillofacial Surgery, Medical Center - University of Freiburg, Faculty of Medicine, University of Freiburg, Germany. 3. Laboratory of Epithelial Biology, Department of Periodontics and Oral Medicine, University of Michigan School, Ann Arbor, MI, USA. 4. Department of Periodontology, School of Dentistry, Oregon Health & Science University, Portland, OR, USA. 5. Department of Periodontology, Institute of Odontology, University of Gothenburg, Gothenburg, Sweden.
Abstract
OBJECTIVES: The mechanisms involved in the initiation and progression of peri-implantitis lesions are poorly understood. It was the aim to determine the content and activation status of macrophages present in human peri-implantitis lesions and compare the current findings with the macrophage polarization associated with periodontitis lesions. MATERIAL AND METHODS: A total of 14 patients were studied in this investigation. Seven were soft tissue biopsies from dental implants affected by peri-implantitis that required explantation. Seven biopsies were from chronic periodontal disease. Immunofluorescence stains were performed using biomarkers to identify macrophages (CD68+ ) undergoing M1 polarization (iNOS+ ) and M2 polarization (CD206+ ), along with Hoechst 33,342 to identify DNA content. All samples were stained and photographed, and double-positive cells for CD68 and iNOS or CD68 and CD206 were quantified. RESULTS: All peri-implantitis biopsies examined revealed a mixed population of macrophages undergoing M1 polarization and M2 polarization. Further analysis demonstrated the co-expression of iNOS and CD206, which indicates the presence of a heterogenic immune response on peri-implantitis lesions. Macrophage polarization in peri-implantitis lesions presents a distinct pattern than in periodontitis. We observed a significant increase in the population of M1 macrophages on peri-implantitis samples compared to periodontal disease samples. CONCLUSION: Our results demonstrate that peri-implantitis has higher numbers of macrophages displaying a distinct macrophage M1 polarization signature compared to periodontitis lesions. This pattern may explain, in part, the distinct nature of peri-implantitis progression vs. periodontitis in humans.
OBJECTIVES: The mechanisms involved in the initiation and progression of peri-implantitis lesions are poorly understood. It was the aim to determine the content and activation status of macrophages present in humanperi-implantitis lesions and compare the current findings with the macrophage polarization associated with periodontitis lesions. MATERIAL AND METHODS: A total of 14 patients were studied in this investigation. Seven were soft tissue biopsies from dental implants affected by peri-implantitis that required explantation. Seven biopsies were from chronic periodontal disease. Immunofluorescence stains were performed using biomarkers to identify macrophages (CD68+ ) undergoing M1 polarization (iNOS+ ) and M2 polarization (CD206+ ), along with Hoechst 33,342 to identify DNA content. All samples were stained and photographed, and double-positive cells for CD68 and iNOS or CD68 and CD206 were quantified. RESULTS: All peri-implantitis biopsies examined revealed a mixed population of macrophages undergoing M1 polarization and M2 polarization. Further analysis demonstrated the co-expression of iNOS and CD206, which indicates the presence of a heterogenic immune response on peri-implantitis lesions. Macrophage polarization in peri-implantitis lesions presents a distinct pattern than in periodontitis. We observed a significant increase in the population of M1 macrophages on peri-implantitis samples compared to periodontal disease samples. CONCLUSION: Our results demonstrate that peri-implantitis has higher numbers of macrophages displaying a distinct macrophage M1 polarization signature compared to periodontitis lesions. This pattern may explain, in part, the distinct nature of peri-implantitis progression vs. periodontitis in humans.
Authors: Nicholas G Fischer; Alexandra C Kobe; Jinhong Dai; Jiahe He; Hongning Wang; John A Pizarek; David A De Jong; Zhou Ye; Shengbin Huang; Conrado Aparicio Journal: Acta Biomater Date: 2021-12-29 Impact factor: 8.947