Shareish (Share & Cherish): an open-source, map-based, web platform to foster mutual aid

peer reviewedIn this paper, we introduce the Shareish web platform to foster mutual aid following principles of gift economy and generalized exchange. Its design is grounded in prior work (in C&T, CSCW, and solidarity HCI) and it aims at leveraging community assets through donation, free loan, requests of goods and services, and free event announcements. Authenticated users can visualize localized items on a map or through lists, search with filters, add new content with rich textual and visual descriptions, discuss about specific content with others users, and get notifications when new content is created in their neighborhood. In addition, we evaluate AI technologies to ease content creation. The platform can be easily replicated and improved by grassroots movements or researchers seeking autonomy as its source code is made freely available and its installation relies on modern deployment strategies. A demonstration server is available (https://shareish.org/, see Section Online Resources).11. Sustainable cities and communitie

CD207+ CD103+ dermal dendritic cells cross-present keratinocyte-derived antigens irrespective of the presence of Langerhans cells

Recent studies have challenged the view that Langerhans cells (LCs) constitute the exclusive antigen-presenting cells of the skin and suggest that the dermal dendritic cell (DDC) network is exceedingly complex. Using knockin mice to track and ablate DCs expressing langerin (CD207), we discovered that the dermis contains five distinct DC subsets and identified their migratory counterparts in draining lymph nodes. Based on this refined classification, we demonstrated that the quantitatively minor CD207+ CD103+ DDC subset is endowed with the unique capability of cross-presenting antigens expressed by keratinocytes irrespective of the presence of LCs. We further showed that Y-Ae, an antibody that is widely used to monitor the formation of complexes involving I-Ab molecules and a peptide derived from the I-E α chain, recognizes mature skin DCs that express I-Ab molecules in the absence of I-E α. Knowledge of this extra reactivity is important because it could be, and already has been, mistakenly interpreted to support the view that antigen transfer can occur between LCs and DDCs. Collectively, these data revisit the transfer of antigen that occurs between keratinocytes and the five distinguishable skin DC subsets and stress the high degree of functional specialization that exists among them