Centre de Recherche du CHUL (CHUQ), 2705 Boulevard Laurier, T-R-93, Quebec, Quebec, Canada G1V 4G2.
J Orthop Res. 2010 Aug;28(8):1084-91. doi: 10.1002/jor.21092.
Neutrophils are the first leukocytes to invade tendons after an acute injury. They could modulate both the inflammatory response and early repair processes through the release of reactive species, cytokines, growth factors, and proteinases. However, the exact role of these cells in damaged tendons remains unclear. We investigated their role by inducing a transient neutropenia in C57BL/6 male mice using an anti-Ly6C/Ly6G antibody. Placebo mice received only serum. The right Achilles tendon was sectioned and sutured using the 8-strand technique, which allowed immediate weight bearing. A significant increase in macrophage accumulation and cell proliferation was observed in tendons from neutropenic animals compared to the placebo group at days 3 and/or 7 postinjury. However, there was a reduction in cell proliferation in a group of mice depleted in macrophages, indicating that macrophages play a role in cell replication in injured tendons. Lastly, the tendons of neutropenic and placebo mice had similar collagen content and mechanical properties at days 7, 14, and/or 28 postinjury. Our findings demonstrate that neutropenia modulates macrophage accumulation and cell proliferation, but overall, a reduction in neutrophil number has no significant effect on tendon repair.
中性粒细胞是急性损伤后最早入侵肌腱的白细胞。它们可以通过释放活性物质、细胞因子、生长因子和蛋白酶来调节炎症反应和早期修复过程。然而，这些细胞在受损肌腱中的确切作用尚不清楚。我们通过使用抗 Ly6C/Ly6G 抗体在 C57BL/6 雄性小鼠中诱导短暂性中性粒细胞减少来研究它们的作用。安慰剂小鼠只接受血清。右跟腱用 8 股技术切开和缝合，允许立即负重。与安慰剂组相比，中性粒细胞减少动物的肌腱在损伤后 3 天和/或 7 天观察到巨噬细胞积累和细胞增殖明显增加。然而，在一组耗尽巨噬细胞的小鼠中，细胞增殖减少，表明巨噬细胞在损伤肌腱的细胞复制中起作用。最后，中性粒细胞减少和安慰剂小鼠的肌腱在损伤后 7、14 和/或 28 天具有相似的胶原含量和机械性能。我们的研究结果表明，中性粒细胞减少症调节巨噬细胞积累和细胞增殖，但总体而言，中性粒细胞数量减少对肌腱修复没有显著影响。
