The Jonathan Boulter Memorial Lecture 2010

Dr Sallusto is Group Leader at the Institute for Research in Biomedicine (IRB) at Bellinzona, Switzerland.

Specific immune responses require the timely interaction of various cell types within specific microenvironments.  In the primary response the rare antigen specific naive T cells need to maximize the possibility of encounter with antigen.  They do so by continuously recirculating through secondary lymphoid organs where they are stimulated by antigen-presenting mature dendritic cells (DCs).  Soluble antigens can reach the lymph node directly but in most cases they are carried by migrating DCs that capture antigen in peripheral tissues and subsequently move through the lymphatics to the draining lymph node.

One goal of Dr Sallusto's laboratory is to understand how the number, localization and activation state of DCs in lymph node impact on T cell priming and immune responses.

A second goal of her research is to dissect the signals by which DCs determine differentiation of proliferating T cells towards the Th1, Th2 or Th17 lineage, and how migratory capacity and effector function are coordinately regulated in differentiating T cells. 

Based on their migratory capacity and effector function Dr Sallusto has originally characterized two subsets of memory T cells: central memory T cells (TCM) express homing receptors for lymph nodes and have no or low level effector function.  In contrast effector memory T cells (TEM) lack lymph node receptors and have immediate effector function.

The Sallusto laboratory is now investigating the molecular basis underlying the functional properties and the differentiation potential of TCM and TEM, their heterogeneity and the signals required for their generation and maintenance.  She is also interested in defining the composition of memory subsets in different pathological and physiological conditions to gain insights into the role these subsets play in the immune responses.

Dr Sallusto has published more than 100 papers, which together have already received >20,000 citations.  She is consequently ranked by Times Higher Education among the 20 Top Scientists in Immunology by total citations (1998-2008), and is listed by Thomson ISI as Highly Cited Researcher in Immunology.

Her groundbreaking report "Efficient presentation of soluble antigen by cultured human dendritic cells is maintained by granulocyte/macrophage colony-stimulating factor plus interleukin 4 and downregulated by tumor necrosis factor alpha" (Sallusto & Lanzavecchia, J Exp Med 1994) is the most highly cited paper ever to be published in the Journal of Experimental Medicine, with >3,200 citations by July 2010.