Eur Endod J. 2019; 4(1): 3-8 | DOI: 10.14744/eej.2018.46330
Programmed Death 1 (PD-1) and PD-1 Ligand (PD-L1) Expression in Chronic Apical Periodontitis
Ronan Jacques Rezende Delgado1, Claudia Ramos Pinheiro1, Thaís Helena Gasparoto1, Carla Renata Sipert2, Ivaldo Gomes De Moraes3, Roberto Brandão Garcia3, Clóvis Monteiro Bramante3, Norberti Bernardineli3, Celso Kenji Nishiyama4, João Santana Da Silva5, Sérgio Aparecido Torres1, Gustavo Pompermaier Garlet1, Ana Paula Campanelli11Department of Biological Sciences, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
2Department of Restorative Dentistry, Discipline of Endodontics, Dental School, University of São Paulo, São Paulo, SP, Brazil
3Department of Operative Dentistry, Endodontics and Dental Materials, Bauru School of Dentistry, University of São Paulo, Bauru, Brazil
4Endodontics Division, Scientific Coordinator of Endodontics Specialty, Dentistry Postgraduate Center, CPO Uningá, Bauru, Sao Paulo, Brazil
5Department of Biochemistry and Immunology, School of Medicine of Ribeirão Preto – University of São Paulo, Ribeirão Preto, SP, Brazil
Objective: This study aimed to examine programmed death protein 1 (PD-1) and programmed death ligand 1 (PD-L1) expression on leukocytes from chronic apical periodontitis, and to determine the levels of cytokines in the apical periodontitis lesions.
Methods: Leukocytes from healthy gingival tissue (n=16) and chronic apical periodontitis (n=10) were evaluated using flow cytometry. The PD-1 and PDL-1 expressions were evaluated using flow cytometry. The cytokine levels were evaluated by enzyme-linked immunosorbent assay. Data were analyzed using one-way ANOVA. The statistical significance level was set at P<0.05.
Results: Results showed that the apical periodontitis lesions are more infiltrated by PD-1+ and PDL1+ lymphocytes than the control samples. In addition, the PDL-1 expression was detected on macrophages in the apical periodontitis lesions, and was significantly higher compared to leukocytes from healthy gingival tissue. The IFN-γ, TGF-β, IL-10, and TNF-α levels were significantly higher in the apical periodontitis lesions compared to control samples.
Conclusion: The PD-1, PD-L1, and CTLA-4 molecules are evident in apical periodontitis, and can be an important immune checkpoint in chronic periapical periodontitis.
Keywords: Chronic periapical periodontitis, cytokines, immunology, lymphocytes, PD-1, PDL-1
Corresponding Author: Ana Paula Campanelli
Manuscript Language: English