Currently, intensive research is being conducted in the field of iPS cells. iPS cells generally have the advantage, with regard to later therapeutic application, that they do not require the destruction of embryos for their procurement/generation/derivation. Furthermore, due to their genetic similarity to the DNA of the persons to be treated, they are usually much better immunologically tolerated than human embryonic stem cells.

Despite the fundamentally better immunological tolerability of iPS cells, rejection reactions still occur, even when iPS cells are used therapeutically. One method to reduce rejection reactions and the use of immunosuppressants is the matching of HLA haplotypes, which is the focus of several projects in iPS research.

The process of reprogramming which genetically ‘resets’ cells can cause the occurrence of short- as well as long-term genetic anomalies in iPS cells. These anomalies can, amongst other things, facilitate tumour growth. Therefore, researchers currently investigate how the process of reprogramming can be altered in order to decrease genetic changes. Additionally, standardised procedures for quality control of iPS cells are being developed.

A further aspect of iPS research consists in improving the efficiency of iPS cell derivation. The procedures applied at present only succeed in reprogramming a small number of somatic cells. However, large numbers of iPS cells are necessary to use them therapeutically. Additionally, hES research as well as iPS research focus on improving the cultivation and safeguarding a targeted as well as homogenous differentiation of stem cells. Furthermore, gaps in knowledge with regard to both stem cell types remain concerning the targeted suppression of cell division of stem cells in vivo that are either undifferentiated or not suitably differentiated.

Besides, stem cell research is targeted at gaining a fundamental understanding of early embryogenesis. Current research thus also attempts to explore the differences between hES cells, iPS cells, adult stem cells and SCNT cells.