TREM2 and Alzheimer disease: A non-autonomous mechanisms is activated by the expression in glia of the chaperon DNAJB6, ortholog of the human HSP-DNAJ, that protects neuronal degeneration and extend lifespan (Bason et al., 2019), A new component is the Triggering Receptor Expressed on Myeloid cells (TREM2), a microglial phagocytic transmembrane receptor, conserved also in flies, for which genetic variations have been associated with senile dementia and increased risk of AD (Filipello et al., 2022).