Kinetics of human myeloid-derived suppressor cells after blood draw.
Kinetics of human myeloid-derived suppressor cells after blood draw.
复制标题
DOI：
10.1186/s12967-015-0755-y
复制
发表时间：
2016-01-06
影响因子：
7.4
通讯作者：
Draenert R
中科院分区：
文献类型：
--
作者：
Grützner E;Stirner R;Arenz L;Athanasoulia AP;Schrödl K;Berking C;Bogner JR;Draenert R
人髓系抑制细胞(MDSC)是一组未成熟的髓系细胞，通过抑制T淋巴细胞的功能发挥免疫抑制作用。虽然在多种人类疾病中研究这些细胞有着巨大的科学兴趣，但在已发表的研究中，方法上的差异很大。这是有问题的，因为人类MDSC似乎是一种敏感的细胞类型，不仅涉及到低温保存，而且还涉及到抽血后的时间点。到目前为止，关于延迟的血液处理对细胞数量和表型的影响的数据尚不清楚。因此，我们评估了采血后粒细胞MDSC(GMDSC)和单核细胞MDSC(MMDSC)频率的动力学，以确定分析这一最近定义的细胞类型的最佳时间点。在本研究中，我们在采血后直接分离HIV感染患者或实体瘤患者的外周血单核细胞(PBMC)。分别于采血后2、4、6小时和休息一夜后用标准表型标记的流式细胞仪分析gMDSC和mMDSC的频率。另外，在PBMC制备后直接冷冻部分细胞，解冻后进行测量。使用新鲜的PBMC，gMDSC水平在一段时间内没有显着差异，但过夜样本的水平有限。然而，冷冻后它们显著减少(p=0.0001，对于所有受试者)。相反，新鲜mMDSC的频率随时间变化，在时间点2和4h之间没有差异，但在6h和过夜休息后显著减少(分别为p=0.0005和p=0.005)。冻存PBMC后，mMDSC产量下降，达到统计学意义(p=0.04)。对于这两个MDSC亚组，随着时间的推移，由于人群之间的分歧不那么明显，FACS分析变得更加困难。根据我们的数据，人的MDSC需要在新鲜的PBMC上进行研究。GMDSC的研究可以延迟，但mMDSC的研究不应迟于采血后4小时。这些结果至关重要，因为如今越来越多的临床试验旨在分析MDSC，而血液处理的后勤在某些情况下意味着样本处理的延迟。本文的在线版本(doi：10.1186/s12967-0150755-y)包含补充材料，授权用户可以使用。
Human myeloid-derived suppressor cells (MDSC) have been described as a group of immature myeloid cells which exert immunosuppressive action by inhibiting function of T lymphocytes. While there is a huge scientific interest to study these cells in multiple human diseases, the methodological approach varies substantially between published studies. This is problematic as human MDSC seem to be a sensible cell type concerning not only cryopreservation but also time point after blood draw. To date data on delayed blood processing influencing cell numbers and phenotype is missing. We therefore evaluated the kinetics of granulocytic MDSC (gMDSC) and monocytic MDSC (mMDSC) frequencies after blood draw in order to determine the best time point for analysis of this recently defined cell type. In this study, we isolated peripheral blood mononuclear cells (PBMC) of patients with HIV infection or solid tumors directly after blood draw. We then analyzed the frequencies of gMDSC and mMDSC 2, 4 and 6 h after blood draw and after an overnight rest by FACS analysis using the standard phenotypic markers. In addition, part of the cells was frozen directly after PBMC preparation and was measured after thawing. gMDSC levels showed no significant difference using fresh PBMC over time with a limitation for the overnight sample. However they were massively diminished after freezing (p = 0.0001 for all subjects). In contrast, frequencies of fresh mMDSC varied over time with no difference between time point 2 and 4 h but a significantly reduction after 6 h and overnight rest (p = 0.0005 and p = 0.005 respectively). Freezing of PBMC decreased the yield of mMDSC reaching statistical significance (p = 0.04). For both MDSC subgroups, FACS analysis became more difficult over time due to less sharp divisions between populations. According to our data human MDSC need to be studied on fresh PBMC. gMDSC can be studied with delay, mMDSC however should be studied no later than 4 h after blood draw. These results are crucial as an increasing number of clinical trials aim at analyzing MDSC nowadays and the logistics of blood processing implies delayed sample processing in some cases. The online version of this article (doi:10.1186/s12967-015-0755-y) contains supplementary material, which is available to authorized users.