Establishment of age-specific reference values of T and B lymphocyte subsets BY multicolor flow cytometry in HEALTHY ADULTS

Immune system cells play a role in the pathogenesis of various diseases such as primary immune deficiency (PID), autoimmunity and cancer. The diversity of disease symptoms and newly defined PID disease groups cause delays in the diagnosis of PID. In recent years, flow cytometers have been used in the diagnosis of PID due to their low cost, rapid and reliable results, antibody and fluorescence diversity. Determination of national reference values in T and B lymphocyte subgroups in healthy individuals is necessary for the correct evaluation of the results of the patients. For this reason, T and B lymphocyte subgroup distributions in blood samples taken from 118 healthy adult individuals (60 males and 58 females) aged between 20 and 60 years, were appreciated with a flow cytometer in terms of both gender and age groups. In our study, CD3+ and CD4+ T lymphocyte cell ratios were found to be higher in females than in males. It was determined that gender and age differences did not affect CD4+ T lymphocytes subgroups distribution, however, the ratios of naive CD8+ T cells decreased and effector memory-CD45RA T (TEMRA) ratios increased in the 50-60 age group. It was displayed that the distribution of regulator T (Treg) cells increased in individuals aged 50-60 years. It was observed that follicular regulator T (TFR) cell ratios increased in 50-60 years old males, whereas follicular helper T (TFH) cell ratios decreased in females compared to males. It was showed up that the differentiation in the direction of helper T (Th)2 and Th17 was higher in females aged 20-29, while this differentiation increased in the direction of Th1 in older age groups. In summary, it is thought that our data will contribute to the evaluation of lymphocyte subgroup distributions by establishing reference ranges for both age and gender differences of T and B lymphocyte subgroups in the healthy adult population.