Evaluation of TNF-α, IL-17A, and YKL-40 in GCF and Serum of Psoriasis Patients and Healthy Controls

Background: Psoriasis is a chronic inflammatory skin disease that affects 2-3% of the global population and is linked to immune dysregulation and systemic inflammation. Periodontitis, a chronic inflammatory gum disease, leads to the destruction of gum tissues and bone. Both conditions share common inflammatory pathways, with key immune mediators such as tumor necrosis factor-alpha (TNF-α), interleukin-17A (IL-17A), and YKL-40 playing a role in tissue destruction and disease progression. However, the biological mechanisms linking psoriasis and periodontitis remain unclear, and few studies have examined localized inflammatory responses in the gums of psoriasis patients. Objectives and Methods: This study aims to evaluate the relationship between psoriasis and periodontitis by measuring TNF-α, IL-17A, and YKL-40 levels in both gingival crevicular fluid (GCF) and serum. A total of 100 participants will be recruited and categorized into three groups: Control (C): Healthy individuals without psoriasis or periodontitis. Gingivitis (G): Individuals diagnosed with gingivitis but without psoriasis. Periodontitis (P): Individuals diagnosed with periodontitis but without psoriasis. Psoriasis with gingivitis (PS+G): Individuals diagnosed with gingivitis but without psoriasis. Psoriasis with Periodontitis (PS+P): Individuals with both psoriasis and periodontitis. All participants will undergo periodontal examinations, including plaque index (PI), bleeding on probing (BOP), probing pocket depth (PPD), and clinical attachment level (CAL). GCF and blood samples will be collected, and biomarker levels will be analyzed using enzyme-linked immunosorbent assay (ELISA). Expected Outcomes and Clinical Relevance: The study will investigate whether systemic inflammation in psoriasis contributes to periodontal disease progression. If psoriasis patients show higher inflammatory biomarker levels, it may suggest a shared immunopathogenic mechanism. The results may contribute to: Earl