Our general scientific interest lies on the study of cellular and molecular mechanisms governing T cell development and function. We are using a T cell receptor (TCR) transgenic mouse model, to study mechanisms underlying peripheral lymphoid homeostasis, function and tolerance of cytotoxic T cells. Particular research projects are:
· Study of the role of the proinflammatory cytokine TNF on cytotoxic T cell responses. Our studies have revealed a novel role for TNF in modulating thresholds for survival, activation, and tolerance of cytotoxic T Cells.
· Development of in vivo imaging technologies.
In collaboration with Dr Jorge Ripoll in the Institute of Electronic Structure and Laser -FORTH we are applying Fluorescent-mediated Molecular Imaging (FMT) techniques to follow in vivo, fluorescently labeled cells. A novel three-dimensional imaging system, suitable for in vivo non-contact FMT, was built by our collaborators and was applied to quantify GFP-expressing thymocytes and peripheral T cells in a transgenic mouse model.
· Study of the role of the negative co-stimulatory pathway PD-1:PD-1L (programmed death 1) on the function of cytotoxic T cells.

Chatzidakis, I. and Mamalaki, C. (2010) T cells as sources and targets of TNF: implications for immunity and autoimmunity. Curr Dir Autoimmun 11: 105-18.

Martin A., Juan Aguirre J., Sarasa A., Tsoukatou D., Garofalakis A., Meyer H., Mamalaki C., Ripoll, J., and Planas A. M. (2008) Imaging changes in lymphoid organs in vivo after brain ischemia with three-dimensional fluorescence molecular tomography in transgenic mice expressing GFP in T-lymphocytes. Molec. Imag. 7: 157-67.

Chatzidakis I., Fousteri G., Tsoukatou D., Kollias G. and Mamalaki C. (2007) An Essential Role for TNF in Modulating Thresholds for Survival, Activation, and Tolerance of CD8+ T cells. J. Immunol. 178: 6735-4.

Garofalakis A, Zacharakis G, Meyer H, Economou EN, Mamalaki C, Papamatheakis J, Kioussis D, Ntziachristos V, and Ripoll J. (2007) Three-dimensional in vivo imaging of green fluorescent protein-expressing T cells in mice with noncontact fluorescence molecular tomography. Molec. Imag. 6: 96-107.