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Yaksh T, Fisher C, Hockman T, Wiese A (2017) Current and future issues in the development of spinal agents for the management of pain. Curr Neuropharmacol 15:232-259.. doi: 10.2174/1570159×14666160307145542

Summary: Although conscious pain experience is driven by signals mediated supraspinally, the more high intensity pain generated by strong stimuli, tissue injury, and nerve injury is encoded at the spinal dorsal horn level. The control of pain signals at the spinal dorsal horn level is a tempting target for targeted pain therapy. This review discusses the potential targets for pain therapeutics in the spinal dorsal horn, and some of the spinal agents used to modulate pain transmission through that location. The use of SSP-SAP (Cat. #IT-11) is mentioned as a neurokinin-1 targeted molecule that can block some pain transmission.

Related Products: SSP-SAP (Cat. #IT-11)

Kaushal R, Taylor B, Jamal A, Zhang L, Ma F, Donahue R, Westlund K (2016) GABA-A receptor activity in the noradrenergic locus coeruleus drives trigeminal neuropathic pain in the rat; contribution of NAα1 receptors in the medial prefrontal cortex. Neuroscience 334:148-159. doi: 10.1016/j.neuroscience.2016.08.005

Summary: The goal of this study was to investigate the role of the locus coeruleus (LC) in a rat orofacial pain model of trigeminal neuropathy induced by chronic constrictive injury of the infraorbital nerve (CCI-ION). Mechanical thresholds to von Frey filaments were tested on whisker pads to evaluate neuropathic pain behavior; pain was indicated by development of mechanical hypersensitivity. Noradrenergic (NA) neurons were lesioned with 5-mcg injections of Anti-DBH-SAP (Cat. #IT-03) into the left lateral ventricle. Mouse-IgG-SAP (Cat. #IT-18) was used as a control. After ablation of NA neurons there was a notable increase in the mechanical threshold compared to control animals. They also targeted coeruleotrigeminal NA neurons by injecting Anti-DBH-SAP into the trigeminal brainstem nuclei bilaterally in one animal and saw similar results. Injecting a GABAA receptor antagonist into the LC after injury had an inhibitory effect on nerve injury induced hypersensitivity. Injection of a NAα1 receptor antagonist, but not a NAα2 receptor antagonist, into the medial prefrontal cortex (mPFC) alleviates mechanical hypersensitivity. They conclude that GABAA-mediated activation of NA neurons during CCI-ION can facilitate hypersensitivity through NAα1 receptors in the mPFC, and that the LC is a chronic pain generator.

Related Products: Anti-DBH-SAP (Cat. #IT-03), Mouse IgG-SAP (Cat. #IT-18)

Nam H, Kerman I (2016) A2 noradrenergic neurons regulate forced swim test immobility. Physiol Behav 165:339-349. doi: 10.1016/j.physbeh.2016.08.020

Summary: Wistar-Kyoto rats are often used as a model of depression, and exhibit high levels of immobility when subjected to a forced swim test (FST). Researchers discovered relative hyperactivation in the locus coeruleus of WKY rats compared to the genetically related Wistar rats when exposed to one- and two-day FSTs. Lesser activation of A2 noradrenergic cell group was seen by diminished levels of FOS after both days of the FST. A2 noradrenergic neurons of Winstar rats were lesioned by injecting 2.2 ug of Anti-DBH-SAP (Cat. #IT-03) into the nucleus tractus solitaris (NTS). Lesioned rats exhibited increased FST immobility on both days of the test, similar to natural WKY behavior in the same test. These data indicate that the A2 noradrenergic cell group regulates FST behavior and that its hypoactivation may contribute to the unique behavioral phenotype of WKY rats.

Related Products: Anti-DBH-SAP (Cat. #IT-03)

Nohara S, Kato K, Fujiwara D, Sakuragi N, Yanagihara K, Iwanuma Y, Kajiyama Y (2016) Aminopeptidase N (APN/CD13) as a target molecule for scirrhous gastric cancer. Clin Res Hepatol Gastroenterol 40:494-503. doi: 10.1016/j.clinre.2015.11.003

Summary: Scirrhous gastric cancer has the worst prognosis of gastric carcinoma, and treatment with standard cancer therapies has had minimal success. In this work the authors target CD13 as a marker for scirrhous gastric cancer. A gastric cancer cell line was challenged with a CD13 antibody coupled to Mab-ZAP (Cat. #IT-04) in an in vitro cytotoxicity assay. The anti-CD13 complex was more cytotoxic than an anti-EpCAM-immmunotoxin. These data, combined with flow cytometry analysis and enzyme activity assays, demonstrate the expression of CD13 as a marker for scirrhous gastric cancer.

Related Products: Mab-ZAP (Cat. #IT-04)

Coradazzi M, Gulino R, Fieramosca F, Falzacappa L, Riggi M, Leanza G (2016) Selective noradrenaline depletion impairs working memory and hippocampal neurogenesis. Neurobiol Aging 48:93-102. doi: 10.1016/j.neurobiolaging.2016.08.012

Summary: Neuronal loss in the locus coeruleus (LC) of Alzheimer’s patients is well known, but the contribution of LC-derived noradrenergic afferents to learning and memory function is unknown. To model noradrenergic neuron degeneration in the LC, rats were bilaterally injected directly into the LC with 0.2 ug of Anti-DBH-SAP (Cat. #IT-03). Lesioned and sham-lesioned animals were tested behaviorally and exhibited robust working memory deficits but lesioning did not affect reference memory. They concluded that ascending noradrenergic afferents might be involved in more complex aspects of working memory, possibly via newly generated progenitors in the hippocampus.

Related Products: Anti-DBH-SAP (Cat. #IT-03)

Araldi D, Ferrari L, Levine J (2016) Gi-protein-coupled 5-HT1B/D receptor agonist sumatriptan induces type I hyperalgesic priming. Pain 157:1773-1782. doi: 10.1097/j.pain.0000000000000581

Summary: The present study explored the possibility that, like MOR and A1-adenosine receptor agonists, triptans would also induce type II hyperalgesic priming. In addition, they explored the 5-HT receptor subtypes at which triptans act (5-HT1B, 5-HT1D and 5-HT7) to induce priming. They report that while sumatriptan, a prototypical 5-HT1B/D receptor agonist induces hyperalgesic priming, this priming meets the criteria for type I rather than type II priming. Isolectin B4 (IB4)-saporin (Cat. #IT-10), was diluted in saline, and a dose of 3.2 μg, in a volume of 20 μL was administered intrathecally to rats. The neurotoxin [Sar9,Met(O2) 11]-substance P-saporin (SSP-Saporin, Cat. #IT-11) was diluted in saline, and a dose of 100 ng, in a volume of 20 μL was administered intrathecally. In a model of pain chronification, sumatriptan induces both mechanical hyperalgesia at the site of injection and type I hyperalgesic priming, in nociceptors innervating the cutaneous injection site.

Related Products: IB4-SAP (Cat. #IT-10), SSP-SAP (Cat. #IT-11)

Kumar J, Rajkumar R, Lee L, Dawe G (2016) Nucleus incertus contributes to an anxiogenic effect of buspirone in rats: Involvement of 5-HT1A receptors. Neuropharmacology 110:1-14. doi: 10.1016/j.neuropharm.2016.07.019

Summary: The nucleus incertus (NI) is involved in stress and anxiety responses. The NI is a cluster of GABAergic neurons in the brainstem, and coexpresses CRF, 5-HT1A and D2 receptors. Buspirone is a partial agonist of 5-HT1A receptors, an antagonist of D2 receptors, and activates the NI. Buspirone is an anti-anxiety drug, but preclinical studies showed that it induces anxiety at high doses. To see if the NI is necessary for the anxiogenic effects of high doses of buspirone, rats were bilaterally injected with 86 ng of CRF-SAP (Cat. #IT-13) into the NI. Blank-SAP (Cat. #IT-21) was used as a control. NI lesioning alone had an anxiogenic effect in several anxiety screening tests compared to sham-lesioned rats, which suggests that the NI reduces anxiety physiologically. Lesioning with CRF-SAP reduced the anxiogenic effects of intra-NI injections of buspirone. No significant difference in the anxiety screening tests resulted from injecting quinpiole, a D2 agonist, which suggests that the 5HT1A receptors in the NI are involved in the anxiogenic effects of buspirone.

Related Products: CRF-SAP (Cat. #IT-13), Blank-SAP (Cat. #IT-21)

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Lim J, Stafford B, Nguyen P, Lien B, Wang C, Zukor K, He Z, Huberman A (2016) Neural activity promotes long-distance, target-specific regeneration of adult retinal axons. Nat Neurosci 19:1073-1084. doi: 10.1038/nn.4340 PMID: 27399843

Summary: Axons in the CNS fail to regenerate after injury. Scientists sought to identify strategies that would allow retinal ganglion cell (RGC) axons to regenerate in the eye-to-brain pathway, and if that was possible, whether the axons could reconnect with their correct targets and restore visual function. It was previously shown that increasing mTOR signaling could trigger RGC axon regeneration. Several conditions were tested, but combining increased mTOR signaling and then exposing mice to high-contrast visual stimulation daily for 3 weeks scientists after optic nerve crush resulted in long distance RGC axon regeneration, re-innervation of the brain and partial recovery of a subset of visual behaviors. A 1:1000 dilution of Anti-Melanopsin (Cat. #AB-N38) was used for the immunohistochemical analysis of retinas, optic nerves and brain tissue.

Related Products: Melanopsin Rabbit Polyclonal (Cat. #AB-N38)

Gilabert-Oriol R, Thakur M, Haussmann K, Niesler N, Bhargava C, Görick C, Fuchs H, Weng A (2016) Saponins from Saponaria officinalis L. augment the efficacy of a Rituximab-immunotoxin. Planta Med 82:1525-1531. doi: 10.1055/s-0042-110495

Summary: It is known that triterpenoidal saponins that come from Saponaria officinalis, the plant that saporin comes from, increases the cytotoxicity of saporin by modulating its intracellular trafficking. Investigators wanted to know if this could increase the therapeutic affect of Rituximab-Saporin. In the presence of saponins, Rituximab-Saporin had a 700-fold increase in efficacy. Concentrations of 0.0001-1nM of Anti-CD22-SAP (Cat. #IT-37) and 0.001-10nM of Anti-CD25-SAP (Cat. #IT-24) were also tested in vitro with saponins for comparison. They saw a 170-fold and 25-fold increase in cytotoxicity, respectively. All conjugates were tested on Ramos cells, and differing levels of receptor expression could explain the drastic differences in cytotoxicity enhancement.

Related Products: Anti-CD22-SAP human (Cat. #IT-37), Anti-CD25-SAP human (Cat. #IT-24)

Palchaudhuri R, Saez B, Hoggatt J, Schajnovitz A, Sykes D, Tate T, Czechowicz A, Kfoury Y, Ruchika F, Rossi D, Verdine G, Mansour M, Scadden D (2016) Non-genotoxic conditioning for hematopoietic stem cell transplantation using a hematopoietic-cell-specific internalizing immunotoxin. Nat Biotechnol 34:738-745. doi: 10.1038/nbt.3584

Summary: To demonstrate correction of a clinically relevant disease, we employed CD45-SAP in a mouse model of sickle cell anemia and demonstrated our method achieved >90% donor cell chimerism, all mice in three groups (18/18), resulting in complete disease correction (red blood cell counts, hemoglobin levels, hematocrit levels and reticulocyte frequencies were returned to normal). If these pre-clinical results can be successfully translated to the clinic, it would greatly reduce conditioning-related toxicities and expand the use of hematopoietic stem cell transplantation.

Related Products: Streptavidin-ZAP (Cat. #IT-27), Anti-CD45.2-SAP (Cat. #IT-91)

Read the featured article in Targeting Trends.