"SPECIAL FOCUS AREA: ENGINEERED TISSUE CONSTRUCTS (ETC). The Defense Sciences Office is interested in innovative proposals to develop the technologies and science for supporting efforts leading to the creation of a three-dimensional ex vivo human immune system. This system will be used for testing new vaccine constructs and immunomodulators that provide superior protection against threat agents. The ETC program seeks to develop reliable methodologies that will accelerate the science and technology base necessary to achieve 3-D tissue engineering and to define the spatial and temporal requirements necessary to expand its applicability. This program intends to encourage multi-disciplinary teams, bringing together a combination of science and engineering communities to achieve its goals. The ability to fabricate functional 3-D ex vivo tissue constructs is limited by current methodologies and materials in 3-D printing, culture methods, bioscaffolding, stem cell biology, and the controlled differentiation of cells. ETC is a two-phase program addressing these limitations. Phase 1 will establish proof-of-concept that human stem cells can be reliably differentiated into multiple immune functions within an in vitro 3-D culture system. ... Phase 2 will focus on continuation of Phase 1 technologies and on producing interactive engineered tissue constructs of the functional elements of the immune system required for both cellular and humeral responses and its appropriate validation."