T and B Cells in Periodontal Disease: New Functions in A Complex Scenario

Area of Science:

• Immunology
• Periodontology
• Oral Medicine

Background:

• Periodontal disease involves chronic inflammation and immune cell infiltration.
• T and B lymphocytes play critical roles in regulating inflammatory responses and tissue homeostasis.
• Understanding immune cell subsets and their functions is vital for managing periodontal disease progression.

Purpose of the Study:

• To review recent findings on the role of T and B cell subsets in periodontal disease pathogenesis.
• To highlight the significance of cytokine expression by immune cells in disease development.
• To explore the impact of specific immune cell activities on bone metabolism in periodontitis.

Main Methods:

• Narrative review of current literature.
• Analysis of T and B cell subsets, including T regulatory (Treg), CD8+, γδ T, and mucosal-associated invariant T (MAIT) cells.
• Examination of cytokine profiles (e.g., IL-17, IFN-γ, TNF-α) and their relation to osteoclastogenesis via RANKL activation.

Main Results:

• Treg, CD8+, and γδ T cells are crucial for maintaining gingival homeostasis.
• Activated T cells secreting IL-17 and SOFAT induce osteoclastogenesis through RANKL.
• MAIT cells may play a significant role in disease pathogenesis due to their cytokine production.
• B cells can influence alveolar bone loss in a RANKL-dependent manner.

Conclusions:

• New functions for Tregs, SOFAT, MAIT cells, and B cells in RANKL activation have been identified.
• The interplay between distinct T and B cell subtypes determines disease outcome, from gingivitis to periodontitis.
• Immune cell dynamics are central to the transition between stable gingivitis and destructive periodontitis.