Department of Pediatric Immunology & Leukocyte Biology, Indian Council of Medical Research - National Institute of Immunohaematology, KEM Hospital, Mumbai, aharashtra, India.
Department of Pediatric Immunology & Leukocyte Biology, Indian Council of Medical Research - National Institute of Immunohaematology, KEM Hospital, Mumbai, Maharashtra, India.
Indian J Med Res. 2023 Aug;158(2):161-174. doi: 10.4103/ijmr.ijmr_3282_21.
BACKGROUND & OBJECTIVES: Accurate diagnosis of immunodeficiencies requires a critical comparison of values with age-matched controls. In India, the existing reference values for rare lymphocyte subsets are currently not available and we rely on the data originating from other countries for the interpretation of the results. Furthermore, there is limited information on normal variation for these rare-subset parameters in Indian children. So, this study aimed to establish normative values for clinically important lymphocyte subsets in Indian children at different age groups.
148 children aged ≥16 yr were enrolled in this study. The study population included 61 per cent males and 39 per cent females and was divided into the following groups: cord blood (n=18), 0-6 months (n=9), 6-12 months (n=13), 1-2 yr (n=19), 2-5 yr (n=27), 5-10 yr (n=25) and 10-16 yr (n=37). The absolute and relative percentage of lymphocytes, T, B, natural killer cell, along with activated, naïve and memory subsets, was determined by flow cytometry.
Median values and the 10 and 90 percentiles were obtained for 34 lymphocyte sub-populations. The T and B naïve compartments showed a decreasing trend, whereas memory cells showed an increase with age. The activated T cell subset shows an increasing pattern up to one year and then declines gradually. Double negative T cells are relatively stable. TCRgd+T cell percentage increases with age.
INTERPRETATION & CONCLUSIONS: This single-centre pilot study provides preliminary data that justifies the need for future large-scale multi centric studies to generate a reference range for interpreting extended immunophenotyping profiles in the paediatric age group, making it possible for clinicians to assess the immunological status in inborn errors of immunity, infectious and autoimmune diseases.
准确诊断免疫缺陷需要对患者值与年龄匹配的对照值进行批判性比较。在印度，目前尚无可用于罕见淋巴细胞亚群的参考值，我们依赖于其他国家的数据来解释结果。此外，印度儿童这些罕见亚群参数的正常变化信息有限。因此，本研究旨在为不同年龄组的印度儿童建立重要临床淋巴细胞亚群的参考值。
本研究纳入了 148 名年龄≥16 岁的儿童。研究人群包括 61%的男性和 39%的女性，分为以下几组：脐血（n=18）、0-6 个月（n=9）、6-12 个月（n=13）、1-2 岁（n=19）、2-5 岁（n=27）、5-10 岁（n=25）和 10-16 岁（n=37）。通过流式细胞术测定淋巴细胞、T、B、自然杀伤细胞以及激活、幼稚和记忆亚群的绝对和相对百分比。
得出了 34 种淋巴细胞亚群的中位数、10%和 90%分位数值。T 和 B 幼稚细胞群呈下降趋势，而记忆细胞则随年龄增长而增加。激活的 T 细胞亚群在一岁前呈上升趋势，然后逐渐下降。双阴性 T 细胞相对稳定。TCRgd+T 细胞百分比随年龄增长而增加。
本单中心初步研究提供了数据，表明需要进行未来的大规模多中心研究，以生成儿科年龄组扩展免疫表型分析的参考范围，使临床医生能够评估免疫缺陷、感染和自身免疫性疾病的免疫状态。
