Recombinant neural progenitor transplants in the spinal dorsal horn alleviate chronic central neuropathic pain

Abstract

Neuropathic pain induced by spinal cord injury (SCI) is clinically challenging with inadequate long-term treatment options. Partial pain relief offered by pharmacologic treatment is often counterbalanced by adverse effects after prolonged use in chronic pain patients. Cell-based therapy for neuropathic pain using GABAergic neuronal progenitor cells (NPC) has the potential to overcome untoward effects of systemic pharmacotherapy while enhancing analgesic potency due to local activation of GABAergic signaling in the spinal cord. However, multifactorial anomalies underlying chronic pain will likely require simultaneous targeting of multiple mechanisms. Here we explore the analgesic potential of genetically modified rat embryonic GABAergic NPCs releasing a peptidergic NMDA receptor antagonist, Serine1-histogranin (SHG), thus targeting both spinal hyperexcitability and reduced inhibitory processes. Recombinant NPCs were designed using either lentiviral or adeno-associated-viral vectors (AAV2/8) encoding single and multimeric (6 copies of SHG) cDNA. Intraspinal injection of recombinant cells elicited enhanced analgesic effects compared to nonrecombinant NPCs in spinal cord injury-induced pain in rats. Moreover, potent and sustained antinociception was achieved, even following a 5 weeks post-injury delay, using recombinant multimeric NPCs. Intrathecal injection of SHG antibody attenuated analgesic effects of the recombinant grafts suggesting active participation of SHG in these antinociceptive effects. Immunoblots and immunocytochemical assays indicated ongoing recombinant peptide production and secretion in the grafted host spinal cords. These results support the potential for engineered NPCs grafted into the spinal dorsal horn to alleviate chronic neuropathic pain.

Experimental Gene Therapy with Serine-Histogranin and Endomorphin 1 for the Treatment of Chronic Neuropathic Pain

“…SHG multimers were generated by adding BglII restriction sites at 5’SHG oligo sequence using PCR (Jergova et al, 2016a ). BglII flanked SHG sequences were annealed to generate SHG multimers and subcloned into a bacterial vector with single SHG.…”

“…Gentamicin (2 mg/kg, i.p.) was injected for 7 days post surgery to prevent bladder infections (Bruce et al, 2002 ; Hama and Sagen, 2007 ; Jergova et al, 2016a ).…”

“…Previous studies have shown that the naturally occurring peptide histogranin (Lemaire et al, 1993 ) and its stable analog Serine-Histogranin (SHG) have NMDA receptor antagonist activity and do not interfere with locomotion (Lemaire et al, 1995 ; Prasad et al, 1995 ; Hama et al, 1999 ; Hama and Sagen, 2002 ; Hentall et al, 2007 ). Furthermore, data has shown marked attenuation of hyperalgesia and allodynia with the spinal introduction of SHG through intrathecal injection or via cell or gene therapy (Siegan et al, 1997 ; NasiriNezhad and Sagen, 2005 ; Gajavelli et al, 2008 ; NasiriNezhad et al, 2015 ; Jergova et al, 2016a , b ).…”

The efficacy of GABAergic precursor cells transplantation in alleviating neuropathic pain in animal models: a systematic review and meta-analysis

“…Recent findings emphasize on the favorable effects of using these cells in alleviating chronic pain. Moreover, injection of these cells has improved and reduced neuropathic pain in animal models [ 14 - 16 ].…”

MiR-139-5p alleviates neural cell apoptosis induced by spinal cord injury through targeting TRAF3

“…The rats were kept warm during the operative process. Rats were anesthetized with intramuscular 10% Chloral Hydrate (3.5 mg/kg) solution (Yaksh et al, 1976;Hama et al, 2009;Jergova et al, 2016). MiR-139-5p agomir and NC agomir were synthesized by GenePharma (Suzhou, China) and adenovirus of TRAF3 plasmids was purchased from Genecreate (Wuhan, China).…”