As in the immune-competent mice (Fig. 1), we found a reduction of amyloid plaque size, number, and insoluble Aβ levels when microglia were depleted early in amyloid plaque deposition (1−4 M) in immunodeficient AppNL-G-F; Rag2-/- mice compared to AppNL-G-F; Rag2-/- mice with intact microglia (Fig. 3a−c). The gene discussed is RAG2; the disease is amyloidosis.