ABSTRACT
Adaptive immunity and T cell function are affected by aging. Calcium influx patterns, regulated by Kv1.3 and IKCa1 potassium channels, influence T cell activation. We aimed to compare calcium influx kinetics in CD8, Th1 and Th2 cells in human peripheral blood samples obtained from five different age groups (cord blood, 10-15 ys, 25-40 ys, 45-55 ys, 60-75 ys).We measured calcium influx using flow cytometry in samples treated with or without specific inhibitors of Kv1.3 and IKCa1 channels (MGTX and TRAM, respectively).Calcium influx was higher in Th1 cells of adults, however, its extent decreased again with aging. Importantly, these changes were not detected in Th2 cells, where the pattern of calcium influx kinetics is similar throughout all investigated age groups. MGTX had a more pronounced inhibitory effect on calcium influx in Th2 cells, while in Th1 cells the same was true for TRAM in the 25-40 ys and 45-55 ys groups. Calcium influx of CD8 cells were inhibited to a similar extent by both applied inhibitors in these groups, and had no effect in the elderly.Altered lymphocyte potassium channel inhibitory patterns, regulators of calcium influx kinetics, might contribute to the development of age-related changes of T cell function.
Subject(s)
Calcium/blood , Fetal Blood/metabolism , Potassium Channels/blood , T-Lymphocytes/metabolism , Adolescent , Adult , Age Factors , Aged , CD8-Positive T-Lymphocytes/immunology , CD8-Positive T-Lymphocytes/metabolism , Child , Female , Fetal Blood/cytology , Humans , Infant, Newborn , Lymphocyte Activation , Male , Middle Aged , T-Lymphocytes/immunology , Th1 Cells/immunology , Th1 Cells/metabolism , Th2 Cells/immunology , Th2 Cells/metabolism , Young AdultABSTRACT
PROBLEM: The prevalence of regulatory T cells (Tregs) is lower in preeclampsia (PE) compared with healthy pregnancy (HP). However, the proportion of recently described Treg subtypes has not been investigated. METHOD: Peripheral blood samples of 19 PE and 21 HP women in the third trimester were evaluated using flow cytometry for the prevalence of activated T cells and naive, effector, thymic, extrathymic, and exhausted Tregs. RESULTS: The prevalence of activated T cells and exhausted Tregs was higher in PE than in HP. The prevalence of the functionally most active effector Tregs is decreased, while naive Tregs appear to be unaffected in PE compared with HP. No difference was detected between Tregs according to their origin (thymic or extrathymic). CONCLUSION: The combination of lower effector Treg and higher exhausted Treg prevalence may account for the decrease in the functionality of Tregs in PE.