Department of Internal Medicine, I.R.C.C.S. "A.O.U. San Martino-IST" and University of Genoa, Genoa, Italy.
Immunohaematology and Transfusion Medicine Unit, Santa Corona Hospital ASL2, Savona, Italy.
Blood Transfus. 2014 Jan;12 Suppl 1(Suppl 1):s214-20. doi: 10.2450/2012.0128-12. Epub 2013 Jan 23.
Platelet-rich plasma consists of platelets concentrated in a small volume of plasma and constitutes a reservoir of bio-modulators potentially useful in tissue repair. The amounts of bio-modulators detectable in platelet-rich plasma prepared with various commercial or "in house" methods have been reported, but virtually all the analyses described have been performed on platelet-rich plasma derived from healthy donors. Since leucocyte contamination is technically unavoidable, we investigated whether platelet-rich plasma prepared from patients could contain different amounts of bio-modulators because of a possible activated status of the leucocytes.
We evaluated platelet-rich plasma prepared with three different techniques (the commercial Vivostat and Biomet recover GPS II systems and an "in house" method) starting from whole blood from healthy donors and patients. Specifically, we compared the levels of sHLA-I, sFasL, platelet-derived growth factor, transforming growth factors-beta and vascular endothelial growth factor in the platelet-rich plasma releasates according to the method of preparation and to the immune system activation status of the subjects.
With the exception of sHLA-I levels, no differences were found in the surrogate indices of lymphocyte activation between healthy donors and patients. No significant differences were found in sHLA-I, sFasL, platelet-derived growth factor, transforming growth factors-beta and vascular endothelial growth factor levels detectable in platelet-rich plasma produced with the three different methods in either healthy donors or patients.
On the whole our findings indicate that the overall content of bio-modulators in autologous platelet-rich plasma is not influenced by T-lymphocyte activation status, at least in patients with uncomplicated femoral fractures. The amounts of sFasL and sHLA-I detected in all the platelet-rich plasma releasates studied were very small, far below the amounts detectable in all clinically available blood derivatives and absolutely insufficient to induce sHLA-I and/or sFasL mediated immunomodulation.
富含血小板的血浆由浓缩在小体积血浆中的血小板组成，是组织修复中潜在有用的生物调节剂的储存库。已经报道了使用各种商业或“内部”方法制备的富含血小板的血浆中可检测到的生物调节剂的量，但是实际上所有描述的分析都是在从健康供体获得的富含血小板的血浆上进行的。由于白细胞污染在技术上是不可避免的，因此我们研究了从患者中制备的富含血小板的血浆是否可能由于白细胞的可能激活状态而包含不同量的生物调节剂。
我们评估了从健康供体和患者的全血开始使用三种不同技术（商业的 Vivostat 和 Biomet recover GPS II 系统以及“内部”方法）制备的富含血小板的血浆。具体而言，我们根据制备方法和受试者的免疫系统激活状态比较了富含血小板的血浆释放物中的可溶性 HLA-I、sFasL、血小板衍生生长因子、转化生长因子-β和血管内皮生长因子的水平。
除了 HLA-I 水平外，健康供体和患者之间淋巴细胞激活的替代指标没有差异。在健康供体和患者中，使用三种不同方法制备的富含血小板的血浆中，sHLA-I、sFasL、血小板衍生生长因子、转化生长因子-β和血管内皮生长因子的水平均无差异。
总的来说，我们的发现表明，自体富含血小板的血浆中生物调节剂的总体含量不受 T 淋巴细胞激活状态的影响，至少在没有复杂股骨骨折的患者中是这样。在研究的所有富含血小板的血浆释放物中检测到的 sFasL 和 sHLA-I 的量非常小，远低于所有临床可用血液衍生物中可检测到的量，绝对不足以诱导 HLA-I 和/或 sFasL 介导的免疫调节。
