3D modeling in cell‐based assays, provides an environment that mimics in vivo conditions. This allows for the examination of innate cellular behavior and aids in the development of next‐generation modeling and therapies. Cellular environments can be modeled using various constituents to manipulate the rigidity, porosity, and size of various 3D environments to observe cell characteristics in an environment similar to that from which they originated. The proliferation of Human Foreskin Fibroblasts (HFF‐1) were examined in a 3D collagen matrix with varying cell densities. Higher cell concentration within the 3D collagen matrix showed lower HFF‐1 cell proliferation. Furthermore, fibrin clots were used to mimic 3D microenvironments because of its biocompatibility and controllable biodegradability. Changing fibrinogen and thrombin concentrations provides a varying effect on the rigidity and porosity of a 3D environment and therefore affects the overall behavior of HFF‐1. There was an increase in fibrin bead size in the presence of cells with higher concentrations of fibrinogen and thrombin. To mimic a bone microenvironment, calcium phosphate (CaP) was introduced in increasing concentrations to support a rigid and structured environment. Increasing concentrations of CaP, resulted in an increase in the initial adhesion and a decrease in HFF‐1 proliferation over a 7‐day incubation period. Overall, cells in a 2D environment behave different than those in a 3D environment with varying components to imitate their in vivo conditions.Support or Funding InformationN/AThis abstract is from the Experimental Biology 2018 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.