CDC researchers have developed an in vitro model system designed to simulate early-stage Mycobacterium tuberculosis infection and induced granuloma formation. This modeling platform can be used for studying tuberculosis pathogenicity, identifying phenotypically-interesting clinical isolates, studying early-stage host cytokine/chemokine responses, and in vitro candidate-drug screening. The approach incorporates autologous human macrophages, human peripheral blood mononuclear cells, and mycobacteria to mimic in situ granuloma formation in a controllable in vitro environment. This technology would be broadly useful for investigations into the numerous facets of early granuloma host-pathogen interaction, ultimately leading to improved prevention, intervention, and treatment strategies.