Reference Ranges of Lymphocyte Subsets in Healthy Qatari Adults

Abstract

Aim: Determine reference ranges of lymphocyte subsets in healthy Qatari adults. Patients & Methods: Blood samples (n = 150) were investigated using four colors flow cytometery. Results: The mean percentage and absolute values of the lymphocyte subsets were: CD3: 73.6 ± 6.1%; 2,072 ± 644 cells/μl; CD4: 41.1 ± 7.9%; 1,167 ± 396 cells/ μl; CD8: 33.8 ± 7.1%; 967 ± 364 cells/μl; B cells (CD19+): 11.3 ± 3.9%; 318 ± 144 cells/μl and natural killer (NK) cells (CD16/56+): 16.5 ± 6.3%, 440 ± 401 cells/μl, respectively. The CD4/CD8 ratio was 1.3 ± 0.5. The ratio, CD3+ and CD4+ percentage and CD4+ cell counts were significantly higher in females; CD8+ and NK cell count and CD8+ percentage were significantly higher in males. The impact of age was less certain. Conclusion:The reference values of lymphocyte subsets appear to be specific to this population, demonstrating the importance of establishing local reference ranges. Keywords: B cells • CD3 • CD4 • CD8 • flow cytometry • lymphocyte subsets • natural killer cells • reference ranges, IntroductionLymphocyte immunophenotyping by flow cytometry is an important tool in differential diagnosis of congenital and acquired immune deficiencies, lymphoproliferative disorders and acute leukemias [1]. In addition, it is used for monitoring treatment response and disease progression with anti-retroviral and immunosuppressive therapy. Various studies suggest that lymphocyte subsets reference ranges are influenced by age, sex, ethnicity, and environment [2][3][4][5]. The variations in the values of the lymphocyte subsets emphasize the importance of establishing local reference ranges to allow for meaningful comparisons and accurate interpretation of immunophenotyping data across different cultures and ethnic groups. Lifestyle factors, e.g. smoking, have also been shown to influence lymphocyte subset values [6,7].Indeed, reference range for peripheral blood lymphocyte subsets have been established in many studies across different countries, revealing variations in the normal range for lymphocyte subsets according to age, sex, race, and environmental factors [3,4,[8][9][10][11][12][13][14][15][16]. Establishment of an internal normal range of lymphocyte subsets is a important for each population considering the effect of environmental factors, age, ethnical diversity on the immune system. Hence, this study aims to determine the laboratory reference ranges for lymphocyte subsets in healthy Qatari adults using flow cytometry.This article reports the local reference range for peripheral blood lymphocyte subsets, both percentages and absolute counts, in a representative sample of 150 healthy adult Qatari population.The results have been stratified by age, sex, and smoking status. The population selected is largely homogenous (100% Qatari Arabs) so effect of race was not investigated. The results are briefly compared with other population data from published studies. Materials & methods SubjectsA total of 150 healthy Qatari volunteers (18-55 yr old; all Qatari Arabs) were recruited for the stud...

Establishment of the reference intervals of lymphocyte subsets for healthy Chinese Han adults and its influencing factors

“…The results of gender differences in NK cells (%) reported in the Israeli (31) study were not observed in this study. In addition, this study did not observe the results of gender differences in CD3 + cells (%), CD3 + cell counts, and CD4 + /CD8 + ratios reported in some studies (16,17,19,20,22,32). The inconsistency of these results may be attributed to differences in the inclusion criteria, sample size, and age distribution of the participants.…”

“…We compared the test results of the 3 flow cytometers: if the data was normally distributed, the analysis of variance (ANOVA) test with a completely random design was used, and the pairwise comparison between the groups used the least significant difference (LSD) test; if the data was non-normally distributed, the Kruskal-Wallis test was used for comparison between the groups, and Nemenyi test was used for pairwise comparison between groups. We used nested ANOVA to test the influence of the above factors on the value of lymphocyte subsets according to the hierarchical relationship of genderage-region, and combined the scatter plot and Z test results to comprehensively consider whether to group to establish reference intervals for lymphatic subsets (17)(18)(19). We used P2.5-P97.5 to set the reference intervals of each lymphatic subset.…”

“…In this study, we found that women's CD4 + cells (%) were higher than men's, while men's absolute counts of NK cells (CD3 − CD16 + CD56 + ) were higher than women's, which is consistent with the results of some previous studies. Studies in South Korea (19), Qatar (21), Brazil (22), Italy (29), and Israel (30) have also observed gender differences in CD4 + cells (%) and the absolute counts of NK cells. However, studies in Qatar (21), Brazil (22), Italy (29), and Israel (30) reported that there are gender differences in the absolute counts of CD4 + cells, as well as in Singapore (15), Hong Kong (18), South Korea (19), and Italy (29).…”

“…Studies in South Korea (19), Qatar (21), Brazil (22), Italy (29), and Israel (30) have also observed gender differences in CD4 + cells (%) and the absolute counts of NK cells. However, studies in Qatar (21), Brazil (22), Italy (29), and Israel (30) reported that there are gender differences in the absolute counts of CD4 + cells, as well as in Singapore (15), Hong Kong (18), South Korea (19), and Italy (29). The results of gender differences in NK cells (%) reported in the Israeli (31) study were not observed in this study.…”

“…Only a few laboratories have established single-center reference intervals, which are not universally representative due to their potential differences in recruitment criteria and detection systems, including using different instruments and detecting methods. It is challenging to establish reference intervals of peripheral blood lymphocyte subsets due to many factors that affect the results, such as recruitment criteria, the patients' age and gender, region, and detection systems (13)(14)(15)(16)(17)(18)(19)(20)(21)(22)(23). However, it is still necessary to establish appropriate reference intervals for as vast applications as possible.…”