Generation and neuronal expression analysis of CX₃CL1 BAC transgenic reporter mice. (A) Schematic of the RedET recombineering method used to replace the first CX₃CL1 exon in the BAC RP24–147I16 with a gene encoding monomeric mCherry reporter gene. Note that the BspEI fragment used as transgene lacks the neighboring CCL22 and CCL17 genes. (B-D) Fluorescent microscopic analysis of hippocampus of CX₃CL1^cherry brain. (B) Red represents CX₃CL1/cherry. (C) Blue represents NeuN staining. (D) Merge with mCherry and NeuN. (E) DCX stained hippocampus slice of CX₃CL1^cherry brain. Red represents CX₃CL1/cherry; and green, DCX staining. (F) CGRP-stained section of CX₃CL1^cherry:CX₃CR1^gfp spinal cord. (G) Dorsal horn. (H) Dorsal root ganglion. Red represents CX₃CL1/cherry; green, CX₃CR1/GFP; and blue, CGRP staining. Lumbar regions (L3-L5). Note CX₃CL1/cherry⁺ somata in dorsal horn but absence of CX₃CL1/cherry expression from CGRP⁺ neuronal cell bodies in dorsal root ganglia.