Journal: bioRxiv
Article Title: A highly efficient method to differentiate CGRP-expressing peptidergic nociceptors from human induced pluripotent stem cells
doi: 10.1101/2025.04.29.651263
Figure Lengend Snippet: a) Workflow for generation of CGRP-GFP reporter line. b) CGRP-GFP expressed in mature TG nociceptors in the absence of placodal isolation, with or without replating (bottom panel, scale bar 5µm). c) Immunocytochemistry reveals co-expression of CGRP and TRPV1 while RET expression is absent suggesting peptidergic subtypes, scale bars 5µm, 50µm. d) Functional analysis by calcium imaging and ELISA on non-GFP iPSC lines, for placodal non-isolated non-replated (left panel, n = 54 cells) placodal non-isolated replated (right panel, n = 35 cells). Calcium imaging shows that these nociceptors are TRPA1/TRPV1-responsive to low dose capsaicin, characteristic of peptidergic sensory neurons. Three independent rounds of differentiation were performed. They also undergo significant CGRP release upon stimulation by inflammatory soup (I.S.) (n = 3 dishes per stimulation per differentiation round, fold change quantified relative to basal release per stimulation, p<0.05). e) Immunocytochemistry and analysis by flow cytometry for placodal non-isolated replated cultures demonstrates co-localization of mature neuronal marker NEUN with peptidergic marker CGRP, further validating their nociceptive identity, scale bars 5µm, 50µm. f) (Top panel) CGRP release quantified by ELISA upon stimulation with 80mM KCl and 1µM PACAP-38. (Bottom panel) CGRP release in response to cAMP (FK, PACAP-38) and cGMP (SNAP, GTN, 8-bromo-cGMP) agonists (n = 3 dishes per stimulation per differentiation round, fold change quantified relative to basal release per stimulation, p<0.05)
Article Snippet: Primary antibodies used were rabbit anti-PAX6 (1:200, Biolegend), goat anti-SIX1 (1:100, SCBT), rabbit anti-CASPASE3 (1:200, ), goat anti-RUNX1 (1:200, SCBT), rabbit anti-cMET (1:200, Abcam), goat anti-PERIPHERIN (1:100, SCBT), rabbit anti-ISLET1 (1:200, Abcam), rabbit anti-BRN3A (1:100, Abcam), mouse anti-TUJ1 (1:1000, Biolegend), rabbit anti-SYNAPTOPHYSIN (1:100, Abcam), rabbit anti-TRPV1 (1:100, Alomone Labs), rabbit anti-5HT 1D (1:100, Alomone labs), mouse anti-CGRP (1:100, Abcam), rabbit anti-TRKA (1:100, Alomone Labs), rabbit-anti RET (1:200, Alomone Labs), rabbit anti-NEUN (1:500, Milipore), chicken anti-GFAP (Abcam) and mouse anti-TUJ1 (Abcam).
Techniques: Isolation, Immunocytochemistry, Expressing, Functional Assay, Imaging, Enzyme-linked Immunosorbent Assay, Flow Cytometry, Marker