Building confidence in skin sensitisation potency assessment using new approach methodologies: report of the 3rd EPAA Partners Forum, Brussels, 28th October 2019.

Skin sensitising substances that induce contact allergy and consequently risk elicitation of allergic contact dermatitis (ACD) remain an important focus regarding the replacement of animal experimentation. Current in vivo methods, notably the local lymph node assay (LLNA) refined and reduced animal usage and led to a marked improvement in hazard identification, characterisation and risk assessment. Since validation, regulatory confidence in the LLNA approach has evolved until it became the first choice assay in most regulated sectors. Currently, hazard identification using the LLNA is being actively replaced by a toolbox of non-animal approaches. However, there remains a need to increase confidence in the use of new approach methodologies (NAMs) as replacements for LLNA sensitiser potency estimation. The EPAA Partners Forum exchanged the current state of knowledge on use of NAMs in various industry sectors and regulatory environments. They then debated current challenges in this area and noted several ongoing needs. These included a requirement for reference standards for potency, better characterisation of applicability domains/technical limitations of NAMs, development of a framework for weight of evidence assessments, and an increased confidence in the characterisation of non-sensitisers. Finally, exploration of an industry/regulator cross-sector user-forum on skin sensitisation was recommended.

Gunshot suicides caused by cane-gun and alarm garden gun cannon: Two cases report."

Obtaining a firearm is not always easy, which is why some firearms that are antique or whose use is not intended to kiss are modified for suicide purposes. The two cases report a suicide with an original historical firearm as the canegun, a walking stick which conceals a firearm and a suicide with a modified alarm cannon, which is a small cannon, which fires blanks to scare away garden animals. The aims of the study were to describe the scene, the corpse external examination and the autopsy to understand the death mechanism. We wish to highlight the importance of the forensic pathologist's fieldwork, especially in complex or atypical suicides.

The CD4(+)CD8(+) and CD4(+) subsets of FOXP3(+) thymocytes differ in their response to growth factor deprivation or stimulation.

The timing of thymic regulatory T (Treg) cell commitment remains unclear. Specifically, there is disagreement as to whether the CD4(+)CD8(+) FOXP3(+) thymocytes are precursors of mature CD4(+) FOXP3(+) Treg cells, or an independent Treg cell lineage. We reasoned that precursors should be more susceptible to apoptosis than mature Treg cells, and tested this by growth factor removal and anti-CD3 stimulation. Both treatments resulted in an increase of CD4(+) FOXP3(+) thymocytes, whereas the frequency of CD4(+)CD8(+) FOXP3(+) thymocytes decreased significantly. These changes were accompanied by an increase of annexin(+) apoptotic cells. Both of these FOXP3(+) subsets expressed higher levels of Bcl-2 and BIM than other thymocytes, and while in our setting expression of BIM seemed to predispose the cells to apoptosis, Bcl-2 had no apparent protective effect. These results indicate that CD4(+)CD8(+) FOXP3(+) thymocytes are more susceptible to apoptosis than mature CD4(+) FOXP3(+) Treg cells. This is consistent with the view that they are still immature and thus likely to represent a precursor population.