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Annual Report for Fiscal Year 2017

Annual Report for Fiscal Year 2017

New Cell Models for Toxicology Better Mimic Human Tissue

NTP researchers are developing cell models that better mimic the structure and function of human tissue for use in high-throughput toxicological testing. The effort is part of the Tox21 initiative to move away from animal testing. Advanced tissue culture models can quickly and reliably identify environmental toxins linked to human disease.

Sreenivasa Ramaiahgari, Ph.D., an NTP postdoctoral fellow, described his work on refining cell models during a January 13, 2017 talk at the Duke University Integrated Toxicology and Environmental Health Program seminar series. Ramaiahgari works in the NTP Biomolecular Screening Branch, the NTP lead for Tox21. His talk, "Organotypic In Vitro Models for Studying Chemical-induced Effects," described his research involving three-dimensional organotypic models—models that behave like living tissue—of liver, kidney, and cancer cells.

Ramaiahgari developed a liver model using progenitor cells, a type of stem cell that can be induced to differentiate into other cell types, including liver cells. Ramaiahgari also developed organotypic tissue models for breast and prostate cell types. These models display tissue-specific functionalities not observed with conventional tissue culture models.

Ramaiahgari’s goal at NTP is to develop organotypic tissue culture models for all tissue types—liver, kidney, lung, heart, breast, neuronal, intestinal, and others—for application in predictive toxicology using high-throughput testing.

Tox21 pipette