Democracy derived? New trajectories in pluripotent stem cell research

Abstract

How has the development of human induced pluripotent stem cells (hiPSCs) modified the trajectory of stem cell research? Here, coauthorship networks of stem cell research articles and analysis of cell lines used in stem cell research indicate that hiPSCs are not replacing human embryonic stem cells, but instead, the two cell types are complementary, interdependent research tools. Thus, we conclude that a ban on funding for embryonic stem cell research could have unexpected negative ramifications on the nascent field of hiPSCs.

Figure 1

Figure 1a: hESC and hiPSC publication trends, 1998–2010 Figure 1b: Uptake of hESC and hiPSC in publications immediately following initial discovery

Figure 2

Proportion of research by type of cell lines used, 2008–2010

Figure 3. Human Pluripotent Stem Cell Co-Authorship Network, 1998–2009

This network image represents co-authorship connections among 5004 authors on publications using hES or hIPS cells from 1998–2009. 509 (9.23%, N=S513) authors are not connected to the primary network component and are not represented. Node size is proportional to the total number of hES and hiPS articles each author published in 2008–2009.

Figure 4. Last Authors using hIPSC, 2008–2009

This network image represents co-authorship connections among the 69 last authors working with hiPSCs in 2008–09. 33 (47.33%) last authors are indirectly connected to each other by prior co-authorship ties in the network component to the left of the figure. That component is dominated by researchers at Harvard and the University of Wisconsin. Six other last authors are connected in the “star” centered on Shinya Yamanaka near the center of the figure. 22 hiPSC last authors (31.88%, arrayed in a circle) are part of the larger co-authorship network in Fig3, but have nut co-authored with another hiPSC last author in our data. Members of the two largest network components are labeled.