CD4 and Lewy body dementia: Intriguingly, DLB-associated CD4+ T cell brain infiltration appears to be maximal in the proximity of blood vessels154, and these cells appear to acquire a TH17 phenotype coupled with pathogenic IL17A secretion in the cerebrospinal fluid downstream of C-X-C motif chemokine ligand 12 (CXCL12)-driven, C-X-C motif chemokine receptor 4 (CXCR4)-mediated recruitment157, a potent chemotactic signalling axis158.