Arnon Group | Lymphocyte trafficking and adaptive immunity
The main focus of the lab is to understand how humoral immune responses are regulated within the spleen.
Tal Arnon is studying mechanisms that regulate lymphocyte migration and humoral immune responses. She obtained her PhD at the Hebrew University of Jerusalem with Professor Ofer Mandelboim, where she focused on understanding how human natural killer cells recognize and eliminate virally infected cells. She then joined Professor Pamela Bjorkman's lab in Caltech to study structural biology of innate immune receptors using x-ray crystallography. During her second postdoc in UCSF with Professor Jason Cyster, she moved on to investigate mechanisms that regulate lymphocytes trafficking in vivo. As part of these studies, she developed new approaches to directly visualize lymphocyte behaviour intravitally in the spleen and other challenging organs. In 2014, she joined the Kennedy Institute as an independent group leader, where she continues to explore how adaptive immune responses are orchestrated within live tissues.
Intravital 2-photon imaging of B cells (green) migrating inside a B cell follicle. Marginal zone macrophages that surround the follicle are highlighted in red. Scale bar, 50m.
The ability of the adaptive immune system to induce long-lasting antibody responses is critical for the clearance of acute infections and is the basis for the development of most vaccines. These responses are primarily triggered within secondary lymphoid organs, including the lymph nodes and spleen, where specialized compartments evolved to maximize the chances of productive activation. To reach these organs and to navigate within their various compartments, lymphocytes constantly migrate. This process is highly dynamic, as it involves transient changes that occur both intrinsically in the migrating cells as well as extrinsically, in the microenvironment. In our lab we study the dynamic and molecular aspects on this process. We focus on exploring mechanisms that guide lymphocyte movement under steady state as well as during activation, differentiation and termination of immune responses. Our goal is to uncover fundamental principles that regulate the adaptive immune system and to harness this knowledge for the development of better vaccines.
This movie illustrates the architecture of the entry paths into T zones. 2-photon intravital imaging of newly transferred T cells (in green) migrating into the splenic white pulp. Endogenous T cells are shown in red. Movies were imaged 24h post transfer.
This movie illustrates the perivascular nature of the entry paths. 2-photn intravital imaging of spleens showing red blood cells (in green) passing at very high speeds inside tracks of T cells (in red).