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Growing older brings about a series of changes in the human body that take place at the cellular and molecular levels. One of NIA’s goals is to support high-quality research that helps to understand these age-related changes and how they impact human health and longevity.
Enhancing the Aging Research Toolbox
Animal models provide valuable information about the aging process, but they do not perfectly reflect the process of human aging. To further our understanding of human aging biology, it is important to explore new methods that complement animal studies, such as those performed in vitro (outside of a living organism).
A good example is microphysiological systems (MPS) that can model a human organ or tissue in cell culture by exposing the cells to factors that are important for their function or that appear in a particular human disease or condition. Further development of MPS (or related tools like tissue chips, organs-on-a-chip, or tissue organoids) will allow researchers to gather new pieces of information about the aging process to give us a more complete picture of how age-related diseases begin in humans, and possible approaches for prevention.
Supporting Aging Research Using In Vitro Systems
Last month, NIA published a new funding opportunity ( RFA-AG-26-014 , Aging Mammalian Tissues In Vitro, R21 Clinical Trial Not Allowed) seeking projects that support the development of three-dimensional mammalian in vitro tissue systems to advance human aging research. The in vitro systems that are supported by this funding opportunity will ideally mimic human aging processes and advance drug discovery efforts. NIA is looking for multidisciplinary teams that include aging biologists alongside experts in stem cell biology, organ physiology, bioengineering, pharmacology, and/or biostatistics to apply for this opportunity. Submissions for this RFA will be accepted from September 20 — October 21, 2025.
Related Efforts at NIH
This RFA builds upon other efforts at NIH to develop new approaches to model human biology, such as the NIH Common Fund’s Complement Animal Research in Experimentation (Complement-ARIE) Program . In addition, the Foundation for the National Institutes of Health (FNIH) is supporting the Complement-ARIE program by catalyzing the development of new approach methodologies (NAMs), which are laboratory or computer-based approaches for safety testing, drug discovery, and modeling human diseases. Currently, FNIH is inviting researchers to submit NAM pilot projects that will further advance the validation and qualification of human-based research models. Submissions will be accepted until December 31, 2025.
We’re Here to Help!
If you have any questions about Complement-ARIE or would like to discuss the development of an application for RFA-AG-26-014, please email Tiziana.Cogliati@nih.gov for more information.
Funding Opportunities 2025-09-29T00:00:00Z