1. Could you explain the significance of your article to the non-specialist? 

To attain the ability to engineer artificial organs or tissues, cells have to be cultured on 3-D substrates.   The cues that these cultured cells, for which stem cells are an exciting starting material, get from interactions with other cells and the substrate, control key signaling pathways. The geometry and surface properties of 3D substrates mediate these interactions and thus govern the fate of the cultured cells. A 3D co-culture system within a LBL surface modified Hydrogel ICC scaffold provides a flexible and systematic 3D cell culture platform to study cellular interactions. In particular, this system facilitates the study of hematopoietic system by efficiently simulating its differentiation niches.

2. What has motivated you to conduct this work? 

We seek to develop fairly universal methods for in-vitro replication of the differentiation niches of hematiopoietic stem cells by using research tools from nanotechnology.   The unique geometry of ICC scaffolds comes from research on photonic crystals. Also, LBL technique which can be used to coat complex surfaces was adopted to modify complex 3D Hydrogel surface to make surfaces bioactive. Ultimately, our goal is the replication of 3D bone marrow and thymus niches for HSCs differentiation into B-cells and T cells, respectively.  

3. Where do you see this work developing in the future? 

The immediate application of our system will be probably be in the area of in-vitro hematopoietic stem cell research. The regularity and uniformity of these scaffolds lends itself to computational modeling, which can be an aid to understanding the process by which cell-cell and cell-matrix interactions mediate differentiation. We anticipate using our system for applications in the drug and vaccine discovery field. 

4. Are there any particular challenges facing future research in this area? 

Although the ICC scaffolds provide a highly regular microenvironment, controlling the differentiation pathway of stem cells is challenging task, because there are far too many unknown parameters in stem cell biology. Chaotic scaffolds introduce an additional layer of complexity in an already challenging area. Our ordered scaffolds eliminate that layer of complexity.