Araldi D, Bogen O, Green PG, Levine JD (2019) Role of nociceptor toll-like receptor 4 (TLR4) in opioid-induced hyperalgesia and hyperalgesic priming. J Neurosci 39(33):6414-6424. doi: 10.1523/JNEUROSCI.0966-19.2019

Objective: To evaluate the hypothesis that hyperalgesia and priming induced by opioids are mediated by similar nociceptor mechanisms.

Summary: Treatment with isolectin B4 (IB4)-saporin or SSP-saporin (which deplete IB4! and peptidergic nociceptors, respectively), or their combination, prevented systemic LDM-induced hyperalgesia, but not priming. HDM-induced priming, but not analgesia, was markedly attenuated in both saporin-treated groups.

Usage: IB4-SAP was diluted in saline and a dose of 3.2 μg in a volume of 20 μl administered intrathecally. SSP-SAP was diluted in saline and a dose of 100 ng in a volume of 20 μl was administered intrathecally.

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

Pinto LG, Souza GR, Kusuda R, Lopes AH, Sant’Anna MB, Cunha FQ, Ferreira SH, Cunha TM (2019) Non-peptidergic nociceptive neurons are essential for mechanical inflammatory hypersensitivity in mice. Mol Neurobiol 56(8):5715-5728. doi: 10.1007/s12035-019-1494-5

Objective: To determine the role of non-peptidergic nociceptors in mediating mechanical inflammatory hypersensitivity in mice.

Summary: rIB4-SAP oblates non-peptidergic neurons as displayed by the decrease of purinoceptor 3. The depletion of these neurons inhibited the mechanical inflammatory sensitivity induced by GDMF and carrageenan, but not by other expected factors such as nerve growth factor implying the role of this subset of neurons to be one of mediation as opposed to direct nociception.

Usage: IB4-SAP (0.16–3.2 μg/5 μl, i.t.), unconjugated Saporin (as control, 1.8 μg/5 μl, i.t.), or saline (vehicle, 5 μl/i.t.) were injected into the subarachnoid space on the midline between the L5 and L6 vertebrae.

Related Products: IB4-SAP (Cat. #IT-10), Saporin (Cat. #PR-01)

Watanabe S, Sakurai T, Nakamura S, Miyoshi K, Sato M (2018) The combinational use of CRISPR/Cas9 and targeted toxin technology enables efficient isolation of bi-allelic knockout non-human mammalian clones. Int J Mol Sci 19:E1075. doi: 10.3390/ijms19041075

Objective: Most genome editing systems employ transient treatment with selective drugs such as puromycin to obtain the desired genome-edited cells, which often allows some untransfected cells to survive and decreases the efficiency of generating genome-edited cells. The authors developed a novel targeted toxin-based drug-free selection system for the enrichment of genome-edited cells.

Summary: Results indicate that a combination of the CRISPR/Cas9 system and targeted toxin technology using IB4-SAP allows efficient enrichment of genome-edited clones, particularly bi-allelic KO clones.

Usage: Cells were trypsinized 3 days after transfection and approximately 80% were incubated for 30 min at 37°C in a solution (25 mcL) containing 0.5–1.0 mcg IB4-SAP (Cat. #IT-10).

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

Israel MR, Morgan M, Tay B, Deuis JR (2018) Toxins as tools: Fingerprinting neuronal pharmacology. Neurosci Lett 679:4-14. doi: 10.1016/j.neulet.2018.02.001

Summary: This review article provides an overview of the experimental techniques used to assess the effects that toxins have on neuronal function, as well as discussion on toxins that have been used as tools, with a focus on toxins that target voltage-gated and ligand-gated ion channels.

Related Products: IB4-SAP (Cat. #IT-10), NPY-SAP (Cat. #IT-28)

Araldi D, Khomula EV, Ferrari LF, Levine JD (2018) Fentanyl induces rapid onset hyperalgesic priming: Type I at peripheral and type II at central nociceptor terminals. J Neurosci 38(9):2226-2245. doi: 10.1523/JNEUROSCI.3476-17.2018

Objective: To evaluate priming, at both nociceptor terminals, the effect of local administration of agents that reverse type I (protein translation) or type II [combination of Src and mitogen-activated protein kinase (MAPK)] priming

Summary: Fentanyl, acting at the -opioid receptor (MOR), induces hyperalgesia and hyperalgesic priming at both the central and peripheral terminal of nociceptors and this is mediated by endoplasmic reticulum Ca2 signaling. Priming in the central terminal is type II, whereas that in the peripheral terminal is type I. Our findings may provide useful information for the design of drugs with improved therapeutic profiles, selectively disrupting individual MOR signaling pathways, to maintain an adequate long-lasting control of pain.

Usage: IB4-SAP was diluted in saline and a dose of 3.2 μg in a volume of 20 μl and administered intrathecally 14 d before experiments

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

Ferrari LF, Khomula EV, Araldi D, Levine JD (2018) CD44 signaling mediates high molecular weight hyaluronan-induced antihyperalgesia. J Neurosci 38(2):308-321. doi: 10.1523/JNEUROSCI.2695-17.2017

Objective: To study the role of the cognate hyaluronan receptor, CD44, signaling in anti-hyperalgesia induced by high molecular weight hyaluronan (HMWH).

Summary: These results demonstrate the central role of CD44 signaling in HMWH-induced anti-hyperalgesia, and establish it as a therapeutic target against inflammatory and neuropathic pain.

Usage: Both IB4-SAP and SSP-SAP were diluted in saline to doses previously shown to deplete nonpeptidergic (3.2 mcg/rat for IB4-SAP) and peptidergic (100 ng/rat for SSP-SAP) fibers. The toxins were administered intrathecally, in a volume of 20 mcl, 14 d before intradermal injection of LMWH on the dorsum of the hindpaw. Treatment with either conjugate, or a combination of the two, did not significantly affect mechanical nociceptive threshold.

Related Products: IB4-SAP (Cat. #IT-10), SSP-SAP (Cat. #IT-11), Anti-CD44-SAP (Cat. #IT-72)

Havelin J, Imbert I, Sukhtankar D, Remeniuk B, Pelletier I, Gentry J, Okun A, Tiutan T, Porreca F, King T (2017) Mediation of movement-induced breakthrough cancer pain by IB4-binding nociceptors in rats. J Neurosci 37:5111-5122.. doi: 10.1523/JNEUROSCI.1212-16.2017

Objective: To define a novel preclinical measure of movement-induced breakthrough pain (BTP) that is observed in the presence of morphine controlling ongoing pain.

Summary: Novel compounds targeting IB4-binding nociceptors may improve pain management for cancer pain patients and other patient populations suffering from BTP that is inadequately treated by currently available medications.

Usage: To determine the effect of eliminating input from IB4-binding fibers, separate groups of rats received spinal administration of IB4-SAP or the control, Blank-SAP (3.2 mcg/20 mcl saline) followed by a 10 mcl flush of saline. Movement of an air bubble placed between drug solution and saline was used to monitor progress of the injection.

Related Products: IB4-SAP (Cat. #IT-10), Blank-SAP (Cat. #IT-21)

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)

La J, Feng B, Kaji K, Schwartz E, Gebhart G (2016) Roles of isolectin B4-binding afferents in colorectal mechanical nociception. Pain 157:348-354. doi: 10.1097/j.pain.0000000000000380

Summary: Primary afferent neurons are often classified as peptidergic or non-peptidergic. One characteristic of the non-peptidergic neurons is that they bind isolectin-B4. In the spinal cord these neurons terminate mainly in inner lamina II. Non-peptidergic neurons in the spinal cord have been found to be involved in various aspects of pain response. In this work the authors examined the role of non-peptidergic neurons in the viscerosensory system. Rats received 1.5 μg of intrathecal recombinant IB4-SAP (Cat. #IT-10) between the L5 and L6 vertebrae. Saporin (Cat. #PR-01) was used as a control. While IHC demonstrated that a majority of viscerosensory L6 colon DRG neurons are IB4+, they do not play a significant role in colorectal mechano-nociception.

Related Products: IB4-SAP (Cat. #IT-10), Saporin (Cat. #PR-01)

Sakurai T, Kamiyoshi A, Kawate H, Mori C, Watanabe S, Tanaka M, Uetake R, Sato M, Shindo T (2016) A non-inheritable maternal Cas9-based multiple-gene editing system in mice. Sci Rep 6:20011. doi: 10.1038/srep20011

Summary: In this work, the authors generated transgenic mice with systemic Cas9 overexpression (Cas9 mice) in order to simplify the procedure of generating genetically modified animals using the CRISPR/Cas9 system – only guide RNAs (gRNAs) would need to be administered to induce mutations at target loci. To test Cas9 mice for genome editing in vitro, the authors transiently transfected primary fibroblasts from Cas9 mice with Ggta1 gRNA (Ggta1 is responsible for synthesizing the cell-surface α-Gal epitope). They treated the fibroblasts with rIB4-SAP (Cat. #IT-10) and found that it killed Ggta1 +/+ and KO/+ cells, while biallelic Ggta1 KO cells survived as they did not synthesize the α-Gal epitope. This indicated that primary cells from the Cas9 transgenic mice have CRISPR/Cas9 genome editing capability with the administration of gRNA alone. The success of their experiments indicate that this method could potentially be used to generate other genetically modified animals.

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