Isolated stem cells are in effect research results that can clearly be distinguished from stem cells in the human body. As such, they should be eligible for both process and product patents under European law, contends a group of researchers from Sweden and the US.

The claim is made in the journal Stem Cells by Professor Mats Hansson, director of the Centre for Bioethics at Sweden’s Karolinska Institute, colleagues from the Centre and Uppsala University, and Professor Rudolf Jaenisch from the Whitehead Institute for Biomedical Research in Massachusetts, US.

As Hansson and his co-authors note, in 2004 the European Patent Office (EPO) rejected an application for five stem cell lines from Wisconsin Alumni Research Foundation (WARF), whose US patents for primate embryonic stem cells have been challenged on the grounds that they severely limit research in this area. Previously, in the ‘Edinburgh case’ involving genetic markers used to identify stem cells, the EPO had concluded that any claims involving human embryonic stem cells violated the European Patent Convention. Both cases are under appeal.

Earlier arguments against patentability

In an opinion presented to the European Commission in May 2002, the European Group on Ethics in Science and New Technologies (EGE) argued that isolating stem cells did not imply modification and hence failed to satisfy the legal requirements for patentability. In the EGE’s view, the only types of cells susceptible to patenting as products would be “cultured lines of cells, propagated from stem cells or stem cell lines, which have been modified either by genetic manipulation, or by treatment that causes the cells to differentiate in a particular way”. In its second report to the Council and European Parliament (July 2005), the Commission said it was too early to reach any definitive conclusion on patenting inventions relating to stem cells.

The Swedish/US group assets, to the contrary, that the only ‘unmodified’ human stem cells “are those still present in the human body or embryo”. When embryonic stem (ES) cells are used to propagate a cell line, the researchers explain, the starting materials or blastocysts are transplanted into a special culture medium and cultured in vitro for an extended period, “generating a novel cell type that is not part of the blastocyst”.

Just the act of placing a cell into a culture medium implies modification, they contend, even if the stem cells are freshly harvested from an organ or tissue. Adaptation to tissue culture results in “the outgrowth of cells that have no equivalent to cells in the embryo”. Similarly, the isolation of adult stem cells requires “stringent section for proliferation and adaptation to growth in tissue culture, and thus produces cells that have no counterpart in the normal animal”.

If an isolated stem cell can be regarded as a “culture artefact”, the researchers say, not only the method of manipulating growth conditions may be patentable but the isolated cell itself, as “a unique result of modifying the cell by placing it in an appropriate medium”. This, they believe, would be compatible with Paragraph 2 of EU Directive 98/44/EC on the legal protection of biotechnical inventions, which states that an “element isolated from the human body …may constitute a patentable invention”.

The authors skirt the moral arguments over the destruction of embryos in stem cell research, which is prohibited under both the European Patent Convention and Directive 98/44/EC. However, they argue, if embryonic stem cell lines create a new type of cell with “novel intrinsic qualities that do not exist in the embryo”, this should resolve another common moral objection to the patentability of stem cells: that they have the potential to develop into a mature human being. The ES cells “do not carry any potentiality, not even in the strong sense [i.e., their intrinsic qualities], and should therefore be in principle patentable”, the authors comment.

They do acknowledge the validity of concerns about the scope of stem cell patents. As they stand, the US patents for primate embryonic stem cells “seem to give WARF far-reaching possibilities to hinder both academic researchers and biotechnology companies from making, using, selling, offering for sale or importing human embryonic stem cells covered by the claims until 2015”, the researchers note. In this light, European authorities should “take a conservative view”, with a “limitation to the intrinsic qualities of both the patented embryonic stem cells and the patented methodologies”.