In a recent study, region-specific alterations in myeloid cell composition was detected in distinct brain regions of TNFtg (TNFα transgenic mouse model of rheumatoid arthritis) mice with rapid activation in the cortex, striatum and thalamus, but very limited alterations in the hippocampus and cerebellum (Süß et al., 2020). The gene discussed is TNF; the disease is rheumatoid arthritis.