My graduate and early postdoctoral training was in theoretical physics and cosmology, but since the late 1990s I have worked as a quantitative immunologist.

Our research integrates theoretical and computational tools with more traditional experimental approaches to study the dynamics of lymphocytes, white blood cells that are key components of vertebrate immune systems. We aim to develop a mechanistic understanding of the rules underlying lymphocyte development, homeostasis, and their trajectories in response to infectious challenge. Our philosophy is to confront and break models with data to search for robust and quantitative explanations of immunological phenomena. Our current interests include the impact of age on lymphocyte persistence and function; the ecology of tissue-resident memory T cells; the recovery of lymphocyte subsets following hematopoietic stem cell transplantation; and the responses of HIV-infected infants to antiretroviral therapy.