Related Experiment Video
Updated: May 13, 2026

Isolation and Th17 Differentiation of Naïve CD4 T Lymphocytes
Published on: September 26, 2013
Th1 and Th2-like protein balance in human inflammatory radicular cysts and periapical granulomas
Carlos Alberto de Carvalho Fraga1, Lucas Rodrigues Alves, Adriana Alkmim de Sousa
1Department of Dentistry, Universidade Estadual de Montes Claros, Montes Claros, Brazil.
Introduction:
Chronic dental periapical lesions result from chronic inflammation of periapical tissues caused by continuous antigenic stimulation from infected root canals. Recent findings have suggested that T helper (Th) 1 and Th2-like cytokines are important in the pathogenesis of chronic periapical inflammatory diseases. However, the mechanisms regulating these immunoinflammatory pathways have not been fully elucidated. Thus, the aim of this study was to evaluate interleukin (IL)-4, IL-12, and interferon γ (IFN-γ) protein levels in human radicular cysts and periapical granulomas.
Methods:
Archived samples of cysts (n = 52) and granulomas (n = 27) were sectioned and submitted to immunohistochemistry to evaluate the tissue expression of IL-4, IL-12, and IFN-γ. The data were analyzed using the Mann-Whitney U test (P < .05).
Results:
An increased expression of IFN-γ was observed in radicular cysts. IL-4 expression was stronger in periapical granulomas than in radicular cysts. IL-12 was not detected in any of the samples.
Conclusions:
Our study showed that IFN-γ protein levels are increased in radicular cysts, whereas IL-4 expression is stronger in samples of periapical granulomas. Further studies are necessary to elucidate the signaling pathways mediated by these cytokines and to facilitate the development of more effective periapical disease management strategies.
Related Concept Videos
T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...
Chronic Inflammation: Introduction
Differentiation of Common Myeloid Progenitor Cells
Inflammatory Response
Inflammation can be triggered by various stimuli, such as impact, abrasion, chemical irritation, infections, and extreme hot or cold temperatures. These can damage cells and connective tissue fibers,...
Inflammatory Bowel Disease II: Ulcerative Colitis
