Ageing is characterized by the progressive lowering of the acute innate immune response and the progressive up-regulation of low-grade inflammation (i.e. inflammaging). At the cellular level, telomeres are considered as a mark of ageing as their length is progressively shortened. However, the links between telomeres and innate immune ageing remain undefined. Using a proteomic approach conducted on laboratory mice, we tested whether the experimental triggering of an acute innate response is deleterious for telomere maintenance, and whether this is dependent of age. To do so, we challenged young and old mice using bacterial lipopolysaccharide (LPS) and measured individuals’ end-points of telomere length and proteomic profiles in spleen tissue.