Translocator protein is a marker of activated microglia in rodent models but not human neurodegenerative diseases

Microglial activation plays central roles in neuroinflammatory and neurodegenerative diseases. Positron emission tomography (PET) targeting 18 kDa Translocator Protein (TSPO) is widely used for localising inflammation in vivo, but its quantitative interpretation remains uncertain. We show that TSPO expression increases in activated microglia in mouse brain disease models but does not change in a non-human primate disease model or in common neurodegenerative and neuroinflammatory human diseases. We describe genetic divergence in the TSPO gene promoter, consistent with the hypothesis that the increase in TSPO expression in activated myeloid cells depends on the transcription factor AP1 and is unique to a subset of rodent species within the Muroidea superfamily. Finally, we identify LCP2 and TFEC as potential markers of microglial activation in humans. These data emphasise that TSPO expression in human myeloid cells is related to different phenomena than in mice, and that TSPO-PET signals in humans reflect the density of inflammatory cells rather than activation state.

Practical reasons and reasonable practice: the case of euthanasia in The Netherlands

Since the early 1970s the issue of euthanasia has been intensely debated in The Netherlands. Through these debates knowledge about medical practices involving the end of life was no longer confined to medical or legal quarters, but became public to a large extent. Following public opinion changes, the legal reaction to euthanasia changed. By prosecuting test cases the public prosecutors allowed the Dutch Supreme Court to formulate specific conditions in which euthanasia would go unpunished. The political debate about changing the criminal law, which still holds that euthanasia is a serious crime, developed at a much slower pace. Several extensive empirical studies were undertaken to gain valid knowledge about the medical practices. This article is concerned with a presentation of the various debates and the changes that took place in the fields of criminal law, politics, and medicine. The main conclusion is the hypothesis that a more open climate for medical practices concerning the end of life allows society to better control these practices.