Dr. Petrovas is currently the head of the Laboratory of Tissue Investigation, at the Institute of Pathology, Department of Laboratory Medicine and Pathology, CHUV, University of Lausanne, Switzerland. His previous work focused on the mechanisms mediating the “exhaustion” of SIV/HIV- specific CD8 T cells and he was the first to describe PD-1 as a mediator of SIV/HIV-specific CD8 T cell survival. More recently, his research has been focused on the dynamics of CD4 and CD8 T cells at tissue level and particularly in the lymph node follicles in HIV and SIV infection. His work was the first to describe the phenotype, localization, molecular profile and dynamics of Tfh CD4 T cells in acute and chronic SIV infection. Currently, he is characterizing the dynamics of tissue immune cells in HIV/SIV and cancer and developing tools to understand the interplay between inflammation, adaptive immunity and tissue antigens.