Mitochondrial functions have a major impact on T-cell functionality. In this study we characterized whether mitochondrial function in the neonatal T-cells differs from that in the adult T-cells during short T-cell activation. Methods: We used fow cytometry methods to test mitochondrial mass and to monitor mitochondrial Ca2+ levels, mitochondrial potential and superoxide generation in parallel with cytoplasmic Ca2+ levels during phythohaemagglutinine-induced activation of CD4+ and CD8+ T-cells of 12 term neonates and 11 healthy adults. Results: Baseline mitochondrial mass of CD4+ and CD8+ cells was lower in the neonate than in the adult. In comparison with the adult, neonatal resting CD4+ T-cells had lower cytoplasmic Ca2+ levels and this was associated with normal activation induced Ca2+-response. During short-term activation cytoplasmic Ca2+-response was lower in neonatal than in adult CD8+ T-cells. Mitochondrial Ca2+ uptake was increased in CD4+ neonatal T cells while it decreased in CD8+ T-cells. Mitochondrial depolarization was increased in CD4+ and decreased in CD8+ neonatal T-cells compared to adults. Superoxide generation was higher and equal in neonatal CD4+ and CD8+ cells, respectively, compared to the adult ones. Conclusion: Our data suggest that neonatal T-cells exhibit marked differences in mitochondrial function and superoxide generation compared to adult T-cells.
Adkins B : Neonatal immunology: responses to pathogenic microorganisms and epigenetics reveal an “immunodiverse” developmental state. Immunol. Res. 57, 246–257 (2013)
Adkins B , Leclerc C, Marshall-Clarke S: Neonatal adaptive immunity comes of age. Nat. Rev. Immunol. 4, 553–564 (2004)
Devadas S , Zaritskaya L, Rhee SG, Oberley L, Williams MS: Discrete generation of superoxide and hydrogen peroxide by T cell receptor stimulation: selective regulation of mitogen-activated protein kinase activation and fas ligand expression. J. Exp. Med. 195, 59–70 (2002)
Duchen MR : Mitochondria and calcium: from cell signalling to cell death. J. Physiol. 529 Pt 1, 57–68 (2000)
Elahi S , Ertelt JM, Kinder JM, Jiang TT, Zhang X, Xin L, Chaturvedi V, Strong BS, Qualls JE, Steinbrecher KA, Kalfa TA, Shaaban AF, Way SS: Immunosuppressive CD71+ erythroid cells compromise neonatal host defence against infection. Nature 504, 158–162 (2013)
Feske S : Calcium signalling in lymphocyte activation and disease. Nat. Rev. Immunol. 7, 690–702 (2007)
García Vela JA , Delgado I, Bornstein R, Alvarez B, Auray MC, Martin I, Oña F, Gilsanz F: Comparative intracellular cytokine production by in vitro stimulated T lymphocytes from human umbilical cord blood (HUCB) and adult peripheral blood (APB). Anal. Cell. Pathol. 20, 93–98 (2000)
Hogan PG , Lewis RS, Rao A: Molecular basis of calcium signaling in lymphocytes: STIM and ORAI. Annu. Rev. Immunol. 28, 491–533 (2010)
Hoth M , Button DC, Lewis RS: Mitochondrial control of calcium-channel gating: a mechanism for sustained signaling and transcriptional activation in T lymphocytes. Proc. Natl Acad. Sci. U.S.A. 97, 10607–10612 (2000)
Jackson SH , Devadas S, Kwon J, Pinto LA, Williams MS: T cells express a phagocyte-type NADPH oxidase that is activated after T cell receptor stimulation. Nat. Immunol. 5, 818–827 (2004)
Jullien P , Cron RQ, Dabbagh K, Cleary A, Chen L, Tran P, Stepick-Biek P, Lewis DB: Decreased CD154 expression by neonatal CD4+ T cells is due to limitations in both proximal and distal events of T cell activation. Int. Immunol. 15, 1461–1472 (2003)
Kalyanaraman B , Darley-Usmar V, Davies KJ, Dennery PA, Forman HJ, Grisham MB, Mann GE, Moore K, Roberts LJ, Ischiropoulos H: Measuring reactive oxygen and nitrogen species with fuorescent probes: challenges and limitations. Free Radic. Biol. Med. 52, 1–6 (2012)
Kaminski BA , Kadereit S, Miller RE, Leahy P, Stein KR, Topa DA, Radivoyevitch T, Veigl ML, Laughlin MJ: Reduced expression of NFAT-associated genes in UCB versus adult CD4+ T lymphocytes during primary stimulation. Blood 102, 4608–4617 (2003)
Kaposi AS , Toldi G, Mészáros G, Szalay B, Veress G, Vásárhelyi B: (2012): Experimental Conditions and Mathematical Analysis of Kinetic Measurements Using Flow Cytometry – The FacsKin Method. In: Flow Cytometry – Recent Perspectives, ed Schmid I, InTech.
Kaposi AS , Veress G, Vásárhelyi B, Macardle P, Bailey S, Tulassay T, Treszl A: Cytometry-acquired calcium-fux data analysis in activated lymphocytes. Cytometry A 73, 246–253 (2008)
Kilpinen S , Hurme M: Low CD3+CD28-induced interleukin-2 production correlates with decreased reactive oxygen intermediate formation in neonatal T cells. Immunology 94, 167–172 (1998)
Mészáros G , Szalay B, Toldi G, Kaposi AS, Vásárhelyi B, Treszl A: Kinetic measurements using fow cytometry: new methods for monitoring intracellular processes. Assay Drug Dev. Technol. 10, 97–104 (2012)
Quintana A , Griesemer D, Schwarz EC, Hoth M: Calcium-dependent activation of T-lymphocytes. Pfugers Arch. 450, 1–12 (2005)
Quintana A , Schwindling C, Wenning AS, Becherer U, Rettig J, Schwarz EC, Hoth M: T cell activation requires mitochondrial translocation to the immunological synapse. Proc. Natl Acad. Sci. U.S.A. 104, 14418–14423 (2007)
Rizzuto R , De Stefani D, Raffaello A, Mammucari C: Mitochondria as sensors and regulators of calcium signalling. Nat. Rev. Mol. Cell Biol. 13, 566–578 (2012)
Roederer M , Treister A, Moore W, Herzenberg LA: Probability binning comparison: a metric for quantitating univariate distribution differences. Cytometry 45, 37–46 (2001)
Sena LA , Li S, Jairaman A, Prakriya M, Ezponda T, Hildeman DA, Wang CR, Schumacker PT, Licht JD, Perlman H, Bryce PJ, Chandel NS: Mitochondria are required for antigen-specifc T cell activation through reactive oxygen species signaling. Immunity 38, 225–236 (2013)
Toldi G , Treszl A, Pongor V, Gyarmati B, Tulassay T, Vásárhelyi B: T-lymphocyte calcium infux characteristics and their modulation by Kv1.3 and IKCa1 channel inhibitors in the neonate. Int. Immunol. 22, 769–774 (2010)
van der Windt GJ , Everts B, Chang CH, Curtis JD, Freitas TC, Amiel E, Pearce EJ, Pearce EL: Mitochondrial respiratory capacity is a critical regulator of CD8+ T cell memory development. Immunity 36, 68–78 (2012)
Williams MS , Kwon J: T cell receptor stimulation, reactive oxygen species, and cell signaling. Free Radic. Biol. Med. 37, 1144–1151 (2004)