Malawi-Liverpool-Wellcome Trust Clinical Research Programme, College of Medicine, University of Malawi, Blantyre, Malawi.
J Allergy Clin Immunol. 2010 Jan;125(1):203-8. doi: 10.1016/j.jaci.2009.10.010. Epub 2009 Nov 26.
CD4(+)T lymphocyte measurements are the most important indicator of mortality in HIV-infected individuals in resource-limited settings. There is currently a lack of comprehensive immunophenotyping data from African populations to guide the immunologic assessment of HIV infection.
To quantify variation in absolute and relative lymphocyte subsets with age in healthy Malawians.
Lymphocyte subsets in peripheral blood of 539 healthy HIV-uninfected Malawians stratified by age were enumerated by flow cytometry.
B and T-lymphocyte and T-lymphocyte subset absolute concentrations peaked in early childhood then decreased to adult levels, whereas lymphocyte subset proportions demonstrated much less variation with age. Adult lymphocyte subsets were similar to those in developed countries. In contrast, high B-lymphocyte and CD8(+)T-lymphocyte levels among children under 2 years, relative to those in developed countries, resulted in low CD4(+)T-lymphocyte percentages that varied little between 0 and 5 years (35% to 39%). The CD4(+)T-lymphocyte percentages in 35% of healthy children under 1 year and 18% of children age 1 to 3 years were below the World Health Organization threshold defining immunodeficiency in HIV-infected children in resource-limited settings. Thirteen percent of healthy children under 18 months old had a CD4:CD8T-lymphocyte ratio <1.0, which is commonly associated with HIV infection. All immunologic parameters except absolute natural killer lymphocyte concentration varied significantly with age, and percentage and overall absolute CD4(+)T-lymphocyte counts were higher in females than males.
Although lymphocyte subsets in Malawian adults are similar to those from developed countries, CD4(+)T-lymphocyte percentages in young children are comparatively low. These findings need to be considered when assessing the severity of HIV-related immunodeficiency in African children under 3 years.
在资源有限的环境中，CD4(+)T 淋巴细胞测量是衡量 HIV 感染者死亡率的最重要指标。目前，缺乏来自非洲人群的综合免疫表型数据来指导 HIV 感染的免疫评估。
量化健康马拉维人群中与年龄相关的绝对和相对淋巴细胞亚群的变化。
通过流式细胞术对按年龄分层的 539 名健康未感染 HIV 的马拉维人外周血中的淋巴细胞亚群进行计数。
B 细胞和 T 细胞及 T 细胞亚群的绝对浓度在儿童早期达到峰值，然后降至成人水平，而淋巴细胞亚群比例随年龄变化较小。成人淋巴细胞亚群与发达国家相似。相比之下，2 岁以下儿童的 B 淋巴细胞和 CD8(+)T 淋巴细胞水平较高，与发达国家相比，导致 CD4(+)T 淋巴细胞百分比在 0 至 5 岁之间变化不大（35%至 39%）。35%的健康 1 岁以下儿童和 18%的 1 至 3 岁儿童的 CD4(+)T 淋巴细胞百分比低于世界卫生组织界定资源有限环境中 HIV 感染儿童免疫缺陷的阈值。18 个月以下的健康儿童中有 13%的 CD4:CD8T 淋巴细胞比值<1.0，这通常与 HIV 感染有关。除绝对自然杀伤细胞淋巴细胞浓度外，所有免疫参数均随年龄显著变化，女性的百分比和总体绝对 CD4(+)T 淋巴细胞计数均高于男性。
尽管马拉维成年人的淋巴细胞亚群与发达国家相似，但幼儿的 CD4(+)T 淋巴细胞百分比相对较低。在评估 3 岁以下非洲儿童 HIV 相关免疫缺陷的严重程度时，需要考虑这些发现。
