■感染是镰状细胞性贫血(SCA)患儿发病的重要原因。然而,目前对SCA中适应性免疫紊乱的范围知之甚少,尤其是撒哈拉以南非洲的人口。在这项研究中,我们调查了坦桑尼亚SCA患儿的T和B淋巴细胞的表型和活化状态。
■我们将30名处于稳态的1-6岁SCA儿童与10名年龄匹配的对照进行了比较。我们评估了白细胞计数,使用自动血液学分析仪和多参数流式细胞术的T和B淋巴细胞表型和活化状态。
■在患有SCA的儿童中,绝对淋巴细胞,单核细胞和粒细胞计数均增加。中央/过渡记忆的比例也有所增加(42.4%vs.33.3%,p=0.0100),效应记忆(7.8%与5.4%,p=0.0086)和终末分化(2.3%vs.1.3%,p=0.0355)CD4+T细胞以及效应记忆CD8+T细胞(21.3%vs.11.5%,p=0.0060)在SCA儿童中。相比之下,天真没有区别,古典记忆,两组之间的非典型记忆和IgM记忆B细胞。有和没有SCA的儿童之间T和B细胞的活化水平相当。此外,我们观察到效应记忆CD8+T细胞的频率与血细胞比容之间存在显著的负相关(Spearmanrho=-0.3859,p=0.0352).
■坦桑尼亚患有SCA的儿童显示出所有白细胞类型的绝对增加,包括淋巴细胞,CD4+和CD8+T细胞向记忆表型倾斜。这些发现为适应性免疫的发展提供了见解,这可能对疫苗反应性产生影响。同种免疫,SCA儿童的自身免疫性疾病和移植免疫学。
UNASSIGNED: Infection is an important cause of morbidity in children with sickle cell anaemia (SCA). However, little is currently known regarding the spectrum of adaptive immune derangement in SCA, especially of populations in Sub-Saharan Africa. In this study, we investigated the phenotype and activation status of T and B lymphocytes among children with SCA in Tanzania.
UNASSIGNED: We compared 30 children with SCA aged 1-6 years in steady-state with 10 age-matched controls. We assessed white blood cell count, T and B lymphocyte phenotype and activation status using an automated haematology analyser and multiparameter Flow Cytometry.
UNASSIGNED: In children with SCA, the absolute lymphocyte, monocyte and granulocyte counts were all increased. There was also an increase in proportion of central/transitional memory (42.4% vs. 33.3%, p = 0.0100), effector memory (7.8% vs. 5.4%, p = 0.0086) and terminally differentiated (2.3% vs. 1.3%, p = 0.0355) CD4+ T cells as well as effector memory CD8+ T cells (21.3% vs. 11.5%, p = 0.0060) in children with SCA. In contrast, there was no difference in naïve, classical memory, atypical memory and IgM memory B-cells between the two groups. The level of activation of both T and B cells were comparable between children with and without SCA. Furthermore, we observed a significant inverse correlation between frequency of the effector memory CD8+ T cells and haematocrit (Spearman rho = -0.3859, p = 0.0352).
UNASSIGNED: Children with SCA in Tanzania show an absolute increase in all leukocyte types, including lymphocytes, with skewing of both CD4+ and CD8+ T cells towards the memory phenotypes. These findings provide insights on the development of adaptive immunity which may have implications on vaccine responsiveness, allo-immunisation, auto-immune diseases and transplant immunology in children with SCA.