The role of Nav1.7 in human nociceptors: insights from human induced pluripotent stem cell-derived sensory neurons of erythromelalgia patients

Jannis E Meents, Elisangela Bressan, Stephanie Sontag, Alec Foerster, Petra Hautvast, Corinna Rösseler, Martin Hampl, Herdit Schüler, Roman Goetzke, Thi Kim Chi Le, Inge Petter Kleggetveit, Kim Le Cann, Clara Kerth, Anthony M Rush, Marc Rogers, Zacharias Kohl, Martin Schmelz, Wolfgang Wagner, Ellen Jørum, Barbara Namer, Beate Winner, Martin Zenke, Angelika Lampert, Jannis E Meents, Elisangela Bressan, Stephanie Sontag, Alec Foerster, Petra Hautvast, Corinna Rösseler, Martin Hampl, Herdit Schüler, Roman Goetzke, Thi Kim Chi Le, Inge Petter Kleggetveit, Kim Le Cann, Clara Kerth, Anthony M Rush, Marc Rogers, Zacharias Kohl, Martin Schmelz, Wolfgang Wagner, Ellen Jørum, Barbara Namer, Beate Winner, Martin Zenke, Angelika Lampert

Abstract

The chronic pain syndrome inherited erythromelalgia (IEM) is attributed to mutations in the voltage-gated sodium channel (NaV) 1.7. Still, recent studies targeting NaV1.7 in clinical trials have provided conflicting results. Here, we differentiated induced pluripotent stem cells from IEM patients with the NaV1.7/I848T mutation into sensory nociceptors. Action potentials in these IEM nociceptors displayed a decreased firing threshold, an enhanced upstroke, and afterhyperpolarization, all of which may explain the increased pain experienced by patients. Subsequently, we investigated the voltage dependence of the tetrodotoxin-sensitive NaV activation in these human sensory neurons using a specific prepulse voltage protocol. The IEM mutation induced a hyperpolarizing shift of NaV activation, which leads to activation of NaV1.7 at more negative potentials. Our results indicate that NaV1.7 is not active during subthreshold depolarizations, but that its activity defines the action potential threshold and contributes significantly to the action potential upstroke. Thus, our model system with induced pluripotent stem cell-derived sensory neurons provides a new rationale for NaV1.7 function and promises to be valuable as a translational tool to profile and develop more efficacious clinical analgesics.

Conflict of interest statement

Sponsorships or competing interests that may be relevant to content are disclosed at the end of this article.

Figures

Figure 1.
Figure 1.
NaV1.7/I848T mutation in IEM patients. (A) Segregation of NaV1.7/I848T mutation in IEM study subjects. IEM 1, mother; IEM 2, daughter; both previously investigated in Ref. . (B) Location of the I848T mutation in the NaV1.7 channel protein. IEM, inherited erythromelalgia.
Figure 2.
Figure 2.
Functional sensory neurons are generated from iPS cells. (A) Differentiation scheme of iPS cells into sensory neurons with dual-SMAD inhibition (LDN193189 and SB431542), VEGF/FGF/PDGF inhibition (SU5402), Notch inhibition (DAPT), and WNT activation (CHIR99021) for 10 days (d0-d10), followed by growth factor (NGF, BDNF, and GDNF)-driven neuron maturation for 8 weeks. On maturation day M35 and M55, neurons were used for analysis. (B) Representative phase-contrast and immunofluorescence images of iPS cell–derived neurons expressing peripherin (green) and TUJ-1 (red) of IEM 1. Scale bar 100 µm. (C and D) Representative immunofluorescence images of neurons from IEM 1 stained positive for NaV1.8 (C) (see also Supplementary Fig. S2, available at http://links.lww.com/PAIN/A749) and TRPV1 (D) (both red) and TUJ-1 (green). Nuclei were counterstained with DAPI (blue). Scale bar 100 µm. (E) Representative calcium imaging recording performed on iPS cell–derived neurons from clone IEM 1. Neurons were stimulated with capsaicin (1 µM), AITC (100 µM), menthol (100 µM), pH 6.0, and KCl (60 mM) for 30 seconds each as indicated. Response profiles of 18 cells are overlaid. For quantification, see Supplementary Figure S3 (available at http://links.lww.com/PAIN/A749). (F) Representative recording of an IEM 1 neuron. Traces display the neuron's total (left) and TTX-r (right) currents, showing functional expression of TTX-r NaV channels. See also Table 1. (G) Representative recording of an IEM 1 neuron, showing functional expression of NaV1.7. Total NaV current is shown before (black) and after (red) 20 minutes of application of the NaV1.7-specific blocker ProTx-II (5 nM). Data shown in (B–E) were gathered on maturation day M35. IEM, inherited erythromelalgia; iPS cell, induced pluripotent stem cell.
Figure 3.
Figure 3.
The IEM mutation changes action potential characteristics. (A) Representative action potentials recorded in IEM 2 (left) and Ctrl 2 (right) nociceptors. Action potential thresholds for each particular neuron are indicated. Dotted line represents 0 mV. (B) The RMP was −47.7 ± 2.4 mV for IEM and −39.3 ± 3.3 for Ctrl nociceptors (n = 24 and 22; P = 0.05 unpaired t test: t = 2.07, df = 44). (C) The action potential threshold was significantly lowered in IEM nociceptors (−45.9 ± 0.6 mV in IEM and −40.1 ± 2.8 mV in Ctrl; n = 23 and 21; P = 0.02, Mann–Whitney test). (D) IEM nociceptors display a stronger hyperpolarization after each action potential (−61.2 ± 0.8 mV for IEM and −45.9 ± 3.7 mV for Ctrl; n = 23 and 21; P < 0.0001, Mann–Whitney test). (E) IEM action potentials had a mean amplitude of 120.9 ± 1.7 mV, compared with 103.1 ± 4.3 mV in Ctrl nociceptors (n = 23 and 21; P = 0.004, Mann–Whitney test). (F) Action potentials in IEM nociceptors had a mean half-width of 2.3 ± 0.6 ms, compared with 8.5 ± 3.8 ms in Ctrl nociceptors (n = 23 and 21; P = 0.02, Mann–Whitney test). (G) The time from pulse onset to the action potential peak is significantly shorter in IEM nociceptors (28.6 ± 2.4 ms, compared with 56.8 ± 11.8 ms in Ctrl; n = 23 and 21; P = 0.019, unpaired t test: t = 2.44, df = 42). (H) Nociceptors for IEM patients have a steeper maximum slope of the action potential upstroke (223.7 ± 13.2 V/s, compared with 136.3 ± 29 V/s in Ctrl; n = 23 and 21; P = 0.007, unpaired t test: t = 2.83, df = 42). (I) The slope of the subthreshold depolarization is not different between IEM and Ctrl nociceptors (1.5 ± 0.1 V/s for IEM vs 1.8 ± 0.3 V/s for Ctrl; n = 23 and 21; P = 0.8, Mann–Whitney test). (J) Action potential (AP) frequency induced by increasing stepwise current injections (n = 14 for IEM and n = 5 for Ctrl; note that some traces are overlaid). None of the measured Ctrl nociceptors fired more than 2 action potentials. The current injection protocol is identical to the one in Supplementary Fig. S5b (available at http://links.lww.com/PAIN/A749). Neurons were held at an RMP around −70 mV and depolarized by square current injections in steps of 0.5 × rheobase to evoke action potential firing. IEM, inherited erythromelalgia; RMP, resting membrane potential.
Figure 4.
Figure 4.
Voltage-clamp protocol to measure TTX-s currents of iPS cell–derived nociceptors. (A–F) Example recordings from a Ctrl 2 nociceptor explain the protocols used in voltage-clamp recordings on iPS cell–derived cells. (A) Shown is the prepulse protocol, used to eliminate space clamp artifacts in this particular Ctrl 2 neuron. The protocol consisted of a short prepulse (generally 4-6 ms, −50 to −15 mV), followed by a repolarizing interpulse (generally 1 ms, −120 to −70 mV), followed by the regular testpulse (40 ms, −80 to +40 mV, 10 mV increments). Prepulse and interpulse voltage and duration were adjusted to each cell individually to eliminate artefacts (F) and obtain optimal voltage-clamp conditions. When tested in NaV1.7-expressing HEK293 cells, such prepulse protocols did not affect voltage dependence of activation of NaV1.7 and provided measurable current amplitudes during the testpulse (Supplementary Fig. S6, available at http://links.lww.com/PAIN/A749). (B) Total current measured in this particular neuron using the protocol shown in (A) before application of TTX. (C) TTX-resistant (TTX-r) current obtained from the same neuron after application of 500 nM TTX. (D) The TTX-sensitive (TTX-s) current component was calculated by subtracting the TTX-r current (C) from the total current (B). (E) Current–voltage (IV) relationships of the same neuron, obtained from the total current (black) shown in (B), the TTX-r current (blue) shown in (C), and the TTX-s current (red) shown in (D). The IV relationships confirm accurate voltage-clamp conditions, achieved by the prepulse protocol shown in (A). Incomplete inactivation of NaVs during the interpulse (here −70 mV) prevents current from reaching zero before the onset of the test pulse (see also B). (F) A regular voltage protocol without prepulse (40 ms, −80 to 40 mV, 10 mV increments) was run on the same neuron at the end of the recording after TTX had already been applied. The recorded TTX-r current shows bad voltage clamp and components from multiple cells, visible as delayed inward current peaks (red and blue with arrows). This confounds current–voltage analysis. iPS cell, induced pluripotent stem cell.
Figure 5.
Figure 5.
The IEM mutation hyperpolarizes the voltage dependence of activation. (A–E) Analysis of the voltage dependence of the TTX-s current component in iPS cell–derived nociceptors. (A) Example traces of TTX-s currents measured in nociceptors from the indicated clones. (B) Current–voltage relationship of TTX-s currents show a left shift in both IEM clones. Current was normalized to the maximum inward current for each group. Due to the applied prepulse protocol, current does not start at 0.0 (Fig. 4). (C) Voltage dependence of activation of TTX-s currents obtained from data in (B). The left shift of the activation curves in both IEM clones is clearly visible. (D) Values for half-maximal voltage-dependent activation (V1/2) of TTX-s currents obtained from data in (C): −24.4 ± 1.8 mV for IEM 1 (P = 0.034 vs Ctrl 1 and P = 0.018 vs Ctrl 2), −24.7 ± 1.1 mV for IEM 2 (P = 0.021 vs Ctrl 1 and P = 0.0099 vs Ctrl 2), −17.6 ± 1.6 mV for Ctrl 1, and -18.7 ± 1.1 mV for Ctrl 2. (E) TTX-s current density showed no significant differences between different clones: 173 ± 15 pA/pF for IEM 1, 151 ± 25 pA/pF for IEM 2, 88 ± 24 pA/pF for Ctrl 1, and 116 ± 14 pA/pF for Ctrl 2 (all P ≥ 0.07). (F) Voltage dependence of activation of total currents, measured before application of TTX. The NaV1.7-mediated left shift is discernible between IEM and Ctrl clones. (G) V1/2 values of total currents obtained from data in (F): −26.5 ± 1.8 mV for IEM 1 (P = 0.006 vs Ctrl 1 and P = 0.002 vs Ctrl 2), −24.4 ± 1.2 mV for IEM 2 (P = 0.073 vs Ctrl 1 and P = 0.092 vs Ctrl 2), −17 ± 1.8 mV for Ctrl 1, and −18.9 ± 1.1 mV for Ctrl 2. (H) Voltage dependence of activation of TTX-r currents. See Table 1 for all V1/2, slope, current density, and n values. All 1-way ANOVA with Bonferroni multiple comparisons test. ANOVA, analysis of variance; IEM, inherited erythromelalgia; iPS cell, induced pluripotent stem cell.
Figure 6.
Figure 6.
Block of NaV1.7 using ProTx-II reveals a hyperpolarized voltage dependence. (A) Representative traces displaying tonic block by 10 nM ProTx-II or vehicle in HEK293 cells, expressing NaV1.7 (upper and middle) or NaV1.6 (lower). Voltage protocol (above) was applied every 2 seconds for 10 minutes. (B) ProTx-II- or vehicle-mediated block in NaV1.7 and 1.6 expressing HEK293 cells. For NaV1.7, vehicle and ProTx-II for 10 minutes reduced peak current by 14.2 ± 4.7% and 56.8 ± 6.4% (P = 0.0001; n = 7 and 8), respectively. For NaV1.6, block was 2.7 ± 4% for vehicle and 20.4 ± 9.8% for ProTx-II (P = 0.45 vs NaV1.6 + vehicle and P = 0.004 vs NaV1.7 + ProTx-II; n = 7 and 4). (C and D) Analysis of the TTX-s current component in iPS cell–derived nociceptors (IEM 2 and Ctrl 2) after incubation in 5 nM ProTx-II for ≥ 10 minutes. (C) Left: TTX-s currents with ProTx-II. Right: TTX-s voltage dependence of activation with ProTx-II (solid lines). For comparison, TTX-s curves without ProTx-II are presented with dashed lines (same as in Fig. 5C). Block of NaV1.7 induces a left shift of activation in control but not in IEM nociceptors. (D) V1/2 values of TTX-s currents with or without ProTx-II: −26.8 ± 1.1 mV (IEM 2) and −25.3 ± 1.9 mV (Ctrl 2) with ProTx-II (P = 0.99). V1/2 values without ProTx-II are presented for comparison (same as in Fig. 5D) (IEM 2: −24.7 ± 1.1 mV, P = 0.99 vs IEM 2 + ProTx-II; Ctrl 2: −18.7 ± 1.1 mV, P = 0.002 vs IEM 2 w/o ProTx-II, P = 0.004 vs Ctrl 2 + ProTx-II, and P = 0.0002 vs IEM 2 + ProTx-II). (E) The total current also shows a left shift of activation in control neurons. For Ctrl 2, V1/2 was −25.9 ± 1.7 mV with ProTx-II, but −18.9 ± 1.1 mV without ProTx-II (P = 0.003). For IEM 2, V1/2 was −26.8 ± 1.1 mV with ProTx-II and −24.4 ± 1.2 mV without ProTx-II (P = 0.99 vs IEM 2 + ProTx-II, P = 0.015 vs Ctrl 2 w/o ProTx-II). Values without ProTx-II are the same as in Fig. 5G. All 1-way ANOVA with Bonferroni multiple comparisons test. ANOVA, analysis of variance; IEM, inherited erythromelalgia; iPS cell, induced pluripotent stem cell.
Figure 7.
Figure 7.
Proposed distribution of NaV channels during action potential generation. Top: schematic representations of action potentials from wild-type (WT, left) or NaV1.7/I848T (right) nociceptors. The individual phases of the action potential are shaded in different colors to match the assumed contribution of different NaV isoforms to each particular phase. Bottom: schematic activation curves for the different NaV channel categories, based on the data presented in this study. We propose that in the wild-type (left panel) NaV1.1, 1.2, 1.3, 1.6, and 1.9 (purple) contribute mainly to subthreshold depolarizations because their voltage dependence is very hyperpolarized. NaV1.7 (red) has a more depolarized activation curve and defines the action potential threshold but also contributes to the upstroke. NaV1.8 (blue) with its very depolarized activation contributes mainly to the action potential upstroke. In patients carrying the IEM mutation NaV1.7/I848T (right panel), activation of NaV1.7 is crucially shifted towards negative potentials. This leads to more synchronized activation of NaV1.7 and other TTX-s NaVs (note the vicinity of the red and purple activation curves). This synchronized activity leads to a lowering of the action potential threshold and to a speeding up of the upstroke. It is possible that NaV1.2 and 1.3 now also contribute to the action potential upstroke in addition to NaV1.7 and 1.8. This further enhances slope and amplitude of the action potential upstroke. Taken together, action potentials in IEM (I848T) patients are faster and larger and display particular changes, summarized on the right. Comparing the 2 graphs of activation curves (bottom panel), please note the shorter X-axis in the bottom right graph. We do not propose a shift of either the purple or the blue (NaV1.8) activation curve. IEM, inherited erythromelalgia.

References

    1. Alexandrou AJ, Brown AR, Chapman ML, Estacion M, Turner J, Mis MA, Wilbrey A, Payne EC, Gutteridge A, Cox PJ, Doyle R, Printzenhoff D, Lin Z, Marron BE, West C, Swain NA, Storer RI, Stupple PA, Castle NA, Hounshell JA, Rivara M, Randall A, Dib-Hajj SD, Krafte D, Waxman SG, Patel MK, Butt RP, Stevens EB. Subtype-selective small molecule inhibitors reveal a fundamental role for Nav1.7 in nociceptor electrogenesis, axonal conduction and presynaptic release. PLoS One 2016;11:e0152405.
    1. Blair NT, Bean BP. Roles of tetrodotoxin (TTX)-sensitive Na+ current, TTX-resistant Na+ current, and Ca2+ current in the action potentials of nociceptive sensory neurons. J Neurosci 2002;22:10277–90.
    1. Blanchard JW, Eade KT, Szűcs A, Lo Sardo V, Tsunemoto RK, Williams D, Sanna PP, Baldwin KK. Selective conversion of fibroblasts into peripheral sensory neurons. Nat Neurosci 2015;18:25–35.
    1. Burbidge SA, Dale TJ, Powell AJ, Whitaker WRJ, Xie XM, Romanos MA, Clare JJ. Molecular cloning, distribution and functional analysis of the NAV1.6. Voltage-gated sodium channel from human brain. Mol Brain Res 2002;103:80–90.
    1. Cao L, McDonnell A, Nitzsche A, Alexandrou A, Saintot PP, Loucif AJC, Brown AR, Young G, Mis M, Randall A, Waxman SG, Stanley P, Kirby S, Tarabar S, Gutteridge A, Butt R, McKernan RM, Whiting P, Ali Z, Bilsland J, Stevens EB. Pharmacological reversal of a pain phenotype in iPSC-derived sensory neurons and patients with inherited erythromelalgia. Sci Transl Med 2016;8:335ra56.
    1. Cestèle S, Scalmani P, Rusconi R, Terragni B, Franceschetti S, Mantegazza M. Self-limited hyperexcitability: functional effect of a familial hemiplegic migraine mutation of the Nav1.1 (SCN1A) Na+ channel. J Neurosci 2008;28:7273–83.
    1. Chambers SM, Qi Y, Mica Y, Lee G, Zhang XJ, Niu L, Bilsland J, Cao L, Stevens E, Whiting P, Shi SH, Studer L. Combined small-molecule inhibition accelerates developmental timing and converts human pluripotent stem cells into nociceptors. Nat Biotechnol 2012;30:715–20.
    1. Clare JJ. Current approaches for the discovery of novel NaV channel inhibitors for the treatment of brain disorders. In: Parnham PMJ, Coward K, Baker MD, editors. Sodium channels, pain, and analgesia. progress in inflammation research. Basel: Birkhäuser, 2005. p. 23–62. 10.1007/3-7643-7411-X_2.
    1. Cox JJ, Reimann F, Nicholas AK, Thornton G, Roberts E, Springell K, Karbani G, Jafri H, Mannan J, Raashid Y, Al-Gazali L, Hamamy H, Valente EM, Gorman S, Williams R, McHale DP, Wood JN, Gribble FM, Woods CG. An SCN9A channelopathy causes congenital inability to experience pain. Nature 2006;444:894–8.
    1. Cummins TR, Aglieco F, Renganathan M, Herzog RI, Dib-Hajj SD, Waxman SG. Nav1.3 sodium channels: rapid repriming and slow closed-state inactivation display quantitative differences after expression in a mammalian cell line and in spinal sensory neurons. J Neurosci 2001;21:5952–61.
    1. Cummins TR, Dib-Hajj SD, Waxman SG. Electrophysiological properties of mutant Nav1.7 sodium channels in a painful inherited neuropathy. J Neurosci 2004;24:8232–6.
    1. Cummins TR, Howe JR, Waxman SG. Slow closed-state inactivation: a novel mechanism underlying ramp currents in cells expressing the hNE/PN1 sodium channel. J Neurosci 1998;18:9607–19.
    1. Dib-Hajj SD, Geha P, Waxman SG. Sodium channels in pain disorders: pathophysiology and prospects for treatment. PAIN 2017;158:S97–S107.
    1. Dib-Hajj SD, Waxman SG. Diversity of composition and function of sodium channels in peripheral sensory neurons. PAIN 2015;156:2406–7.
    1. Dib-Hajj SD, Yang Y, Black JA, Waxman SG. The NaV1.7 sodium channel: from molecule to man. Nat Rev Neurosci 2013;14:49–62.
    1. Eberhardt E, Havlicek S, Schmidt D, Link AS, Neacsu C, Kohl Z, Hampl M, Kist AM, Klinger A, Nau C, Schüttler J, Alzheimer C, Winkler J, Namer B, Winner B, Lampert A. Pattern of functional TTX-resistant sodium channels reveals a developmental stage of human iPSC- and ESC-derived nociceptors. Stem Cell Rep 2015;5:305–13.
    1. Emery EC, Habib AM, Cox JJ, Nicholas AK, Gribble FM, Woods CG, Reimann F. Novel SCN9A mutations underlying extreme pain phenotypes: unexpected electrophysiological and clinical phenotype correlations. J Neurosci 2015;35:7674–81.
    1. Hampl M, Eberhardt E, O'Reilly AO, Lampert A. Sodium channel slow inactivation interferes with open channel block. Sci Rep 2016;6:25974.
    1. Han C, Dib-Hajj SD, Lin Z, Li Y, Eastman EM, Tyrrell L, Cao X, Yang Y, Waxman SG. Early- and late-onset inherited erythromelalgia: genotype–phenotype correlation. Brain 2009;132:1711–22.
    1. Han C, Estacion M, Huang J, Vasylyev D, Zhao P, Dib-Hajj SD, Waxman SG. Human Na(v)1.8: enhanced persistent and ramp currents contribute to distinct firing properties of human DRG neurons. J Neurophysiol 2015;113:3172–85.
    1. Herzog RI, Cummins TR, Ghassemi F, Dib-Hajj SD, Waxman SG. Distinct repriming and closed-state inactivation kinetics of Nav1.6 and Nav1.7 sodium channels in mouse spinal sensory neurons. J Physiol 2003;551:741–50.
    1. Kamiya K, Kaneda M, Sugawara T, Mazaki E, Okamura N, Montal M, Makita N, Tanaka M, Fukushima K, Fujiwara T, Inoue Y, Yamakawa K. A nonsense mutation of the sodium channel gene SCN2A in a patient with intractable epilepsy and mental decline. J Neurosci 2004;24:2690–8.
    1. Lampert A, Eberhardt M, Waxman SG. Altered sodium channel gating as molecular basis for pain: contribution of activation, inactivation, and resurgent currents. In: Ruben PC, editor. Voltage gated sodium channels. Handbook of experimental pharmacology. Berlin: Springer, 2014. p. 91–110. Available at: . Accessed September 24, 2014.
    1. Lampert A, O'Reilly AO, Dib-Hajj SD, Tyrrell L, Wallace BA, Waxman SG. A pore-blocking hydrophobic motif at the cytoplasmic aperture of the closed-state Nav1.7 channel is disrupted by the erythromelalgia-associated F1449V mutation. J Biol Chem 2008;283:24118–27.
    1. Lenz M, Goetzke R, Schenk A, Schubert C, Veeck J, Hemeda H, Koschmieder S, Zenke M, Schuppert A, Wagner W. Epigenetic biomarker to support classification into pluripotent and non-pluripotent cells. Sci Rep 2015;5:8973.
    1. Lin Z, Santos S, Padilla K, Printzenhoff D, Castle NA. Biophysical and pharmacological characterization of Nav1.9 voltage dependent sodium channels stably expressed in HEK-293 cells. PLoS One 2016;11:e0161450.
    1. Middleton RE, Warren VA, Kraus RL, Hwang JC, Liu CJ, Dai G, Brochu RM, Kohler MG, Gao YD, Garsky VM, Bogusky MJ, Mehl JT, Cohen CJ, Smith MM. Two tarantula peptides inhibit activation of multiple sodium channels. Biochemistry 2002;41:14734–47.
    1. Milescu LS, Bean BP, Smith JC. Isolation of somatic Na+ currents by selective inactivation of axonal channels with a voltage prepulse. J Neurosci 2010;30:7740–8.
    1. Minett MS, Pereira V, Sikandar S, Matsuyama A, Lolignier S, Kanellopoulos AH, Mancini F, Iannetti GD, Bogdanov YD, Santana-Varela S, Millet Q, Baskozos G, MacAllister R, Cox JJ, Zhao J, Wood JN. Endogenous opioids contribute to insensitivity to pain in humans and mice lacking sodium channel Nav1.7. Nat Commun 2015;6:8967.
    1. Namer B, Ørstavik K, Schmidt R, Kleggetveit IP, Weidner C, Mørk C, Kvernebo MS, Kvernebo K, Salter H, Carr TH, Segerdahl M, Quiding H, Waxman SG, Handwerker HO, Torebjörk HE, Jørum E, Schmelz M. Specific changes in conduction velocity recovery cycles of single nociceptors in a patient with erythromelalgia with the I848T gain-of-function mutation of Nav1.7. PAIN 2015;156:1637–46.
    1. Nassar MA, Stirling LC, Forlani G, Baker MD, Matthews EA, Dickenson AH, Wood JN. Nociceptor-specific gene deletion reveals a major role for Nav1.7 (PN1) in acute and inflammatory pain. Proc Natl Acad Sci U S A 2004;101:12706–11.
    1. Prè D, Nestor MW, Sproul AA, Jacob S, Koppensteiner P, Chinchalongporn V, Zimmer M, Yamamoto A, Noggle SA, Arancio O. A time course analysis of the electrophysiological properties of neurons differentiated from human induced pluripotent stem cells (iPSCs). PLoS One 2014;9:e103418.
    1. Qin J, Sontag S, Lin Q, Mitzka S, Leisten I, Schneider RK, Wang X, Jauch A, Peitz M, Brüstle O, Wagner W, Zhao RC, Zenke M. Cell fusion enhances mesendodermal differentiation of human induced pluripotent stem cells. Stem Cell Dev 2014;23:2875–82.
    1. Renganathan M, Cummins TR, Waxman SG. Contribution of Na(v)1.8 sodium channels to action potential electrogenesis in DRG neurons. J Neurophysiol 2001;86:629–40.
    1. Rostock C, Schrenk-Siemens K, Pohle J, Siemens J. Human vs. mouse nociceptors–similarities and differences. Neuroscience 2017;387:13–27.
    1. Royeck M, Horstmann MT, Remy S, Reitze M, Yaari Y, Beck H. Role of axonal NaV1.6 sodium channels in action potential initiation of CA1 pyramidal neurons. J Neurophysiol 2008;100:2361–80.
    1. Rush AM, Dib-Hajj SD, Liu S, Cummins TR, Black JA, Waxman SG. A single sodium channel mutation produces hyper- or hypoexcitability in different types of neurons. Proc Natl Acad Sci U S A 2006;103:8245–50.
    1. Schmalhofer WA, Calhoun J, Burrows R, Bailey T, Kohler MG, Weinglass AB, Kaczorowski GJ, Garcia ML, Koltzenburg M, Priest BT. ProTx-II, a selective inhibitor of NaV1.7 sodium channels, blocks action potential propagation in nociceptors. Mol Pharmacol 2008;74:1476–84.
    1. Shields SD, Deng L, Reese RM, Dourado M, Tao J, Foreman O, Chang JH, Hackos DH. Insensitivity to pain upon adult-onset deletion of Nav1.7 or its blockade with selective inhibitors. J Neurosci 2018;38:10180–201.
    1. Theile JW, Jarecki BW, Piekarz AD, Cummins TR. Nav1.7 mutations associated with paroxysmal extreme pain disorder, but not erythromelalgia, enhance Navβ4 peptide-mediated resurgent sodium currents. J Physiol 2011;589:597–608.
    1. Vanoye CG, Kunic JD, Ehring GR, George AL. Mechanism of sodium channel NaV1.9 potentiation by G-protein signaling. J Gen Physiol 2013;141:193–202.
    1. Wainger BJ, Buttermore ED, Oliveira JT, Mellin C, Lee S, Saber WA, Wang AJ, Ichida JK, Chiu IM, Barrett L, Huebner EA, Bilgin C, Tsujimoto N, Brenneis C, Kapur K, Rubin LL, Eggan K, Woolf CJ. Modeling pain in vitro using nociceptor neurons reprogrammed from fibroblasts. Nat Neurosci 2015;18:17–24.
    1. Wu MT, Huang PY, Yen CT, Chen CC, Lee MJ. A novel SCN9A mutation responsible for primary erythromelalgia and is resistant to the treatment of sodium channel blockers. PLoS One 2013;8:e55212.
    1. Xie X, Dale TJ, John VH, Cater HL, Peakman TC, Clare JJ. Electrophysiological and pharmacological properties of the human brain type IIA Na+ channel expressed in a stable mammalian cell line. Pflugers Arch 2001;441:425–33.
    1. Yang Y, Wang Y, Li S, Xu Z, Li H, Ma L, Fan J, Bu D, Liu B, Fan Z, Wu G, Jin J, Ding B, Zhu X, Shen Y. Mutations in SCN9A, encoding a sodium channel alpha subunit, in patients with primary erythermalgia. J Med Genet 2004;41:171–4.
    1. Young GT, Gutteridge A, Fox HD, Wilbrey AL, Cao L, Cho LT, Brown AR, Benn CL, Kammonen LR, Friedman JH, Bictash M, Whiting P, Bilsland JG, Stevens EB. Characterizing human stem cell–derived sensory neurons at the single-cell level reveals their ion channel expression and utility in pain research. Mol Ther 2014;22:1530–43.
    1. Zhang X, Priest BT, Belfer I, Gold MS. Voltage-gated Na+ currents in human dorsal root ganglion neurons. eLife 2017;6:e23235.
    1. Zhang Z, Schmelz M, Segerdahl M, Quiding H, Centerholt C, Juréus A, Carr TH, Whiteley J, Salter H, Kvernebo MS, Ørstavik K, Helås T, Kleggetveit IP, Lunden LK, Jørum E. Exonic mutations in SCN9A (NaV1.7) are found in a minority of patients with erythromelalgia. Scand J Pain 2014;5:217–25.

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