Effects of thrombospondin-1 (THBS1) and toll-like receptor 4 (TLR-4) levels in the serum and synovial fluid of patients with knee osteoarthritis.

BACKGROUND: To explore the changes in and significance of Thrombospondin-1 (THBS1) and Toll-like receptor 4 (TLR-4) levels in the serum and joint fluid of patients with knee osteoarthritis (KOA). METHODS: 184 KOA patients admitted to our hospital between May 2022 and February 2025 were selected as the observation group, and 64 healthy adults who underwent physical examinations at the same hospital during the same period composed the control group. Tumour necrosis factor-α (TNF-α), interleukin (IL)-1 b, THBS1, and TLR-4 levels in the two groups' serum and joint fluid were compared. The correlations between TNF-α, IL-1 b, THBS1, and TLR-4 levels in the serum and synovial fluid of the two groups and the severity of KOA were evaluated, and the clinical value of THBS1 and TLR-4 in the diagnosis of KOA was analysed. RESULTS: TNF-α, IL-1β, THBS1, and TLR-4 levels in the observation group's serum and joint fluid were considerably higher than those in the control group (P< 0.05). With increasing Kellgren-Lawrence (K-L) grade, the observation group's serum and joint fluid showed higher levels of TNF-α, IL-1β, THBS1, and TLR-4. When TNF-α, IL-1β, THBS1, and TLR-4 levels were compared among K-L grades, statistically significant differences were found (P< 0.05). The K-L grade of the patients was positively correlated with TNF-α, IL-1β, THBS1, and TLR-4 in the blood and joint fluid (P< 0.05), and the factors of TNF-α, IL-1β, THBS1, andTLR-4 in the observation group's serum and joint fluidwere positively correlated with each other (P< 0.05). Thesensitivity and specificity of serum THBS1 and TLR-4 forthe diagnosis of KOA were 0.916 and 0.889, and 0.825and 0.865, respectively, and the optimal cutoff values were247.262 and 5.084 ng/mL, respectively. The sensitivityand specificity of THBS1 and TLR-4 in the joint fluid fordiagnosing KOA were 0.945 and 0.932, and 0.985 and0.916, respectively, and the optimal cutoff values were239.745 and 4.620 ng/mL, respectively. CONCLUSIONS: THBS1 and TLR-4 in serum and synovial fluid can serve as potential markers for the clinical diagnosis and assessment of KOA, with high diagnostic efficacy. Moreover, detecting serum THBS1 and TLR-4 is less invasive, less costly, and more acceptable to patients.