Effects of hyaluronic acid (HA) viscosupplementation on peripheral Th cells in knee and hip osteoarthritis

Abstract

Objective: Determine Th lymphocytes concentration in patients with knee or hip osteoarthritis (OA). Evaluate their change after HA viscosupplementation.

Methods: Patients with early primary knee or hip OA (ACR Criteria) were recruited in two groups: group A was only observed longitudinally, group B was treated with a course of three weekly intra-articular injections of HA. A healthy control group gender and age matched was enrolled too. All subjects were followed for 3 months. Flow cytometry was performed from blood samples to assess T cells subpopulations (CD3, CD4, CD8, CCR6, CD38, CxCR3, HLA DR) at baseline and at 3-months visit.

Results: 86 patients were recruited with OA: 49 in Group A (35 knee OA, 14 hip OA), 37 in Group B (24 knee OA, 13 hip OA). 23 in Control Group. Activated CD4 T cells (CD4(+)CD38(+)DR(+), CD4(+)CD38(-)DR(+)), Th2 (CD4(+)CXCR3(-)CCR6(-)),Th1 (CD4(+)CXCR3(+)CCR6(-)) were higher at baseline in group A and B than in control group. After the HA course activated T cells were lower in group B than in group A (P = 0.01). Th17 (CD4(+)CXCR3(-)CCR6(+)) at baseline were higher in groups A and B than in control group and decreased levels in Group B after the HA course were observed (P = 0.03).

Conclusion: The presence of activated T cells in patients with OA confirm that OA is a disease with an immunological/inflammatory involvement. Our preliminary results seems to show that HA injections could lower the levels of activated T cells, and so regulate the articular milieu.

Keywords: Osteoarthritis; Th cells; Viscosupplementation.