5^th European Immunology Conference

Biography

Biography: Sankar Bhattacharyya

Abstract

Established tumor cause suppression of host immune system and recent studies indicate that a chronic pro inflammatory situation develops along with neoplastic progression. MDSCs are a group of heterogeneous immature myeloid lineage cells with potent T-cell suppressor activity that accumulate during inflammation and cancer. Although a good deal is known about suppressive effect of established tumor on host immune system, very little reports are available on effect of growing tumor on host immune system during very initial days. In order to study role of tumor immune interaction and influence of pro inflammatory milieu on tumor establishment we used mice model and a liquid transplantable murine tumor, EAC and carried out immunophenotyping studies. So far our study indicates that during very initial stage of tumor establishment a large number of T cells, majority of which is of activated/memory status infiltrate the tumor site. As tumor start to establish itself through direct and indirect intervention it depletes the tumor site T cell population and/or make them functionally inactive. Secondary lymphoid organ T cell reserve is not significantly affected though. We also observed significant infiltration of MDSC at tumor sit and increased proportion of these cells in bone marrow of tumor bearing animals, spleen remained relatively unaffected. An increased presence of macrophage was noticed in the ascites during initial stage but replaced by immature cells latter on. Together our data provides preliminary indication that tumor initially progress like pathogenic infection and immune system reacts similarly to this initial tumor cell population as it does against classic infection, causing increased infiltration of T cells and macrophages at tumor site, but as tumor starts to establish it manipulates microenvironment to deplete infiltrating T cells or render them ineffective.