TrkB-positive sensory neurons are putative mechanoreceptors. a–d Double immunofluorescence of DRG sections from TrkBCreERT2::Rosa26RFP mice with a NF200, b Ret, visualized using TrkBCreERT2::Rosa26RFP::RetEGFP triple transgenic mice, c IB4, d quantification of staining on mouse DRG sections; TrkB+ cells account for ~10% of all DRG neurons and all co-express NF200 or NF200 + ReteGFP, while they are negative for IB4, CGRP, and TH. e–h Double immunofluorescence of human DRG sections stained with antibodies against TrkB and e NF200, f Ret, g TrkA. h Size distribution for human DRG neurons expressing TrkB, NF200, and TrkA. i Section through the lumbar spinal cord of TrkBCreERT2::AvilmCherry mice stained with IB4. j TrkB+ lanceolate endings in a section of the back hairy skin of TrkBCreERT2::Rosa26SnapCaaX labeled with Snap Cell TMRstar (red), NF200 (green), and DAPI (blue). k Section from the glabrous skin of TrkBCreERT2::Rosa26ChR2YFP (red) stained with anti-S100 a marker for Meissner’s corpuscles (green) and DAPI (blue) showing TrkB+ innervation. l Section from human glabrous skin stained with antibodies against TrkB (red) and NF200 (green), and DAPI (blue). Scale bars, a–c and i 50 μm, e–g and j–l 40 μm.