de Molla Vinicius Campos, Barbosa Míriam Cristina Rodrigues, Junior Alfredo Mendrone, Gonçalves Matheus Vescovi, Guirao Eliza Kimuraa Fabio, Yamamoto Mihoko, Arrais-Rodrigues Celso
Universidade Federal de São Paulo (Unifesp), São Paulo, SP, Brazil; Hospital 9 de Julho, São Paulo, Brazil.
Universidade Federal de São Paulo (Unifesp), São Paulo, SP, Brazil.
Hematol Transfus Cell Ther. 2023 Oct-Dec;45(4):419-427. doi: 10.1016/j.htct.2022.07.001. Epub 2022 Aug 19.
Umbilical cord blood (UCB) is an alternative source of hematopoietic stem cells for allogeneic hematopoietic stem cell transplantation in the absence of a compatible donor. The UCB transplantation has a lower incidence of chronic graft versus host disease (GvHD), but is associated with slower engraftment and slower immune reconstitution, compared to other sources. Dendritic cells (DCs) and Natural Killer cells (NKs) play a central role in the development of GvHD and the graft versus leukemia (GvL) effect, as well as in the control of infectious complications.
We quantified by multiparametric flow cytometry monocytes, lymphocytes, NK cells, and DCs, including their subsets, in UCB samples from 54 healthy newborns and peripheral blood (PB) from 25 healthy adult volunteers.
In the UCB samples, there were higher counts of NK cells 5616 (median 0.024 × 109/L), compared to the PB samples (0.012 × 109/L, p < 0.0001), NK 5616 (median 0.446 × 109/L vs. 0.259 × 109/L for PB samples, p = 0.001) and plasmacytoid dendritic cells (pDCs, median 0.008 × 109/L for UCB samples vs. 0.006 × 109/L for PB samples, p = 0.03). Moreover, non-classic monocyte counts were lower in UCB than in PB (median 0.024 × 109/L vs. 0.051 × 109/L, respectively, p < 0.0001).
In conclusion, there were higher counts of NK cells and pDCs and lower counts of non-classic monocytes in UCB than in PB from healthy individuals. These findings might explain the lower incidence and severity of chronic GvHD, although maintaining the GvL effect, in UCB transplant recipients, compared to other stem cell sources.
在缺乏匹配供体的情况下，脐带血（UCB）是同种异体造血干细胞移植的另一种造血干细胞来源。与其他来源相比，UCB移植的慢性移植物抗宿主病（GvHD）发病率较低，但与植入较慢和免疫重建较慢有关。树突状细胞（DCs）和自然杀伤细胞（NKs）在GvHD的发展、移植物抗白血病（GvL）效应以及感染并发症的控制中起着核心作用。
我们通过多参数流式细胞术对54名健康新生儿的UCB样本和25名健康成年志愿者的外周血（PB）中的单核细胞、淋巴细胞、NK细胞和DCs（包括其亚群）进行了定量分析。
与PB样本相比，UCB样本中的NK细胞计数更高（中位数为0.024×10⁹/L，而PB样本为0.012×10⁹/L，p<0.0001），NK 5616（中位数为0.446×10⁹/L，PB样本为0.259×10⁹/L，p = 0.001）以及浆细胞样树突状细胞（pDCs，UCB样本中位数为0.008×10⁹/L，PB样本为0.006×10⁹/L，p = 0.03）。此外，UCB中非经典单核细胞计数低于PB（中位数分别为0.024×10⁹/L和0.051×10⁹/L，p<0.0001）。
总之，与健康个体的PB相比，UCB中NK细胞和pDCs计数更高，非经典单核细胞计数更低。这些发现可能解释了与其他干细胞来源相比，UCB移植受者慢性GvHD的发病率和严重程度较低，同时维持了GvL效应。
