Relevance of local Th2-type cytokine mRNA expression in immunocompetent infiltrates in inflamed gingival tissue to periodontal diseases

Abstract

It has been suggested that the types of inflammatory round cell infiltrates and the divergence in the cytokine production profile by macrophages and helper T cells regulate the course of infectious or inflammatory diseases, including periodontitis and gingivitis. We examined the expression of IL‐1α, IL‐1β, IL‐2, IL‐4, IL‐5, IL‐6 and tumour necrosis factor‐alpha (TNF‐α) mRNA in the inflamed gingiva by in situ hybridization. The results of single‐cell analysis were used as data sets for statistical analyses. The density of cells expressing IL‐1α, IL‐4 and IL‐5 mRNA was higher in periodontitis than in gingivitis. IL‐2 mRNA‐expressing cells were almost absent in gingivitis specimens. Principal component analysis disclosed three factors explaining 84.8% of the variance: one accounting for 40.5% of the variance and mainly regulated by IL‐1α, IL‐1β, IL‐6 and TNF‐α, and two others, explaining 29.9% and 14.4% of the variance, describing the relationship between the types of cytokines derived from macrophages or Th2 type. These results suggest that the cytokines produced by inflammatory cells infiltrating in the gingival tissue are influential on the progression of gingivitis, an acute and reversible inflammatory condition, to chronic and destructive periodontitis. Thus, periodontal disease progression may be regulated by the local cytokine network, and the bias in this network towards a Th2‐type cytokine dominance could be an exacerbating factor.

Comparison of Th1/Th2 cytokine profiles of initial wound healing of rats induced by PDCM and e‐PTFE

“…16 Recent studies have indicated that Th1-dominated responses tend to protect against periodontal tissue destruction, while Th2-dominated responses tend to aggravate the breakdown. 17,18 In a previous study of cellular immunity elicited by PDCM, result showed that PDCM might elicit a delayed type of hypersensitivity in the early stage of wound healing. 14 The ratio of CD4 ϩ/CD8 ϩ cells was 2/1.…”

The Role of Distinct T Cell Subsets in Periodontitis—Studies from Humans and Rodent Models

“…In humans, numerous studies have supported the hypothesis that Th1 cells are associated with stable lesions and Th2 cells are associated with progressive lesions [35][36][37][38][39][40]. In contrast, several studies have demonstrated that upregulation of Th1 responses or downregulation of Th2 responses are involved in periodontal tissue destruction [41][42][43].…”

Molecular docking studies on rocaglamide, a traditional Chinese medicine for periodontitis

“…Several studies have associated Th1 and Th2 with the etiology of periodontitis [10][11][12][13][14]. Th1 and Th2 are the important components of the immune response which are associated with inflammatory disease and allergic reaction, respectively.…”