Friedrich-Alexander University is the second largest University (11 faculties, 265 chairs, 22 000 students) of the state of Bavaria with a broad spectrum of interacting disciplines and a high degree of interdisciplinary research funding (SFB, GRK). Research at the medical faculty is characterized by close interaction between clinical research and basic science with interdisciplinary main research foci in infectiology/immunology and oncology. The laboratory of viral T-cell leukaemia is part of the German National Reference Centre for Retroviruses (NRZ) at the Institute of Clinical and Molecular Virology. The Institute’s research interests center on the molecular biology of retroviruses, Herpesviruses and viral induction of lymphoid malignancies. The laboratory’s focus is the molecular analysis of Human T-cell leukaemia virus (HTLV-1) and its impact on cellular growth.

An aggressive and fatal leukaemia termed adult T-cell leukaemia (ATL) is a frequent result of infection by the human T-cell leukaemia virus (HTLV-1). ATL develops after decades of HTLV-persistence from expanding non-malignant virally infected T-cell clones. The virus persists preferentially in CD4 and CD8 positive T-cells, which most closely resemble memory T-cells. These cells are adapted to long term persistence and thus are believed to express efficient survival functions, which could be a prerequisite for the leukaemic transformation. In addition enhancement of survival functions by viral factors are essential for development of the leukemia and may critically depend on the T-cell subtype. General aim of our project is to identify relevant survival functions of HTLV-1 infected cells during the leukemogenic process. Under INCA we want to: investigate the viral stimulation of antiapoptotic functions/pathways in memory T-cell. Memory T-cells will be purified from peripheral blood and transduced with virus or Tax alone. Expression of antiapoptotic functions and activation of relevant signal transduction pathways will be comparatively analyzed in infected and non-infected cells. The applied methodology will include immuno-magnetic cell separation, cDNA microarrays, real-time PCR, and indicator luciferase assays; identify (survival-) functions potentially relevant for leukemogenesis. The capacity for long-term persistence in both CD4 and CD8 T-cells contrasts the malignant conversion of only CD4 cells. To identify pathways and survival gene functions relevant for premalignant/malignant cell growth, CD4 and CD8 memory T-cells and ATL-cells shall be compared with respect to expression of the genes above and of survival-specific pathways using cDNA microarray technology; analyse the relevance of isolated upregulated genes for cell growth and their potential as therapeutic targets. The endogenous expression of isolated promising candidate genes will be repressed in ATL-derived and HTLV-transformed cultures by RNAi (shRNA expressing lentiviruses) and the consequences on apoptosis and growth rates will be determined. These topics will be investigated in close collaboration with other members of the INCA consortium, in particular with the laboratories of Charles Bangham, Vincenzo Ciminale and Luc Willems.

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