The questions we would like to address in the next few years include how cortical and medullary microenvironments in the thymus positively and negatively select functionally potent and self-tolerant T cell repertoire. We would also like to study the mechanisms involved in how diverse microenvironments are formed in the thymus to shape T cell repertoire and how multiple thymic microenvironments sequentially guide to position developing T cells for their repertoire formation.