targeted-toxins

Szysiak N, Kosior-Korzecka U, longo V, Patkowski K, Greguła-Kania M, Nowakiewicz A, Bochniarz M,Junkuszew A (2025) Influence of neurokinin b, dynorphin a and kisspeptin-10 on in vitro gonadotropin secretion by anterior pituitary cells isolated from pubescent ewes. J Vet Res doi: 10.2478/jvetres-2025-0003

Objective: The aim of the study was to analyze the direct effect of the hypothalamic neuropeptides kisspeptin-10, neurokinin B, and dynorphin A on gonadotropin secretion by pituitary cells isolated from pubescent ewes.

Summary: Puberty is a multifactorial and complex process in animal development and in the case of livestock, timely attainment of sexual maturity contributes to increased reproductive efficiency, which leads to higher profitability. Studies revealed that kisspeptin, neurokinin B and dynorphin neuropeptides, collectively referred to as KNDy neuropeptides, are recognized as the key neuropeptides produced and secreted by the arcuate nucleus of the hypothalamus (ARC), and involved in the endocrine regulation of the onset of puberty. They all play roles in the endocrine regulation of the hypothalamic-pituitary-ovarian (HPO) axis in puberty. Kisspeptin-10, NKB and Dyn A had a direct impact on gonadotropin secretion by ovine pituitary cells. However, a detailed explanation of their role in gonadotropin secretion by the anterior pituitary gland in sheep and their impact on the regulation of the HPO axis during sexual maturation or in the pathomechanism of delayed puberty requires further studies.

Usage: Prepubertal ewes received 1 μL (0.7 μg) of NKB-SAP (NK3-SAP) [IT-63] or Blank-SAP (IT-21) injections aimed at the arcuate (ARC) nucleus to ablate neurons expressing NK3R.

Related Products: NKB-SAP (Cat. #IT-63), Blank-SAP (Cat. #IT-21)

See Also:

• Aerts EG et al. The effect of NK3-Saporin injection within the arcuate nucleus on puberty, the LH surge, and the response to Senktide in female sheep. Biol Reprod 110(2):275-287, 2024.

Vringer M, Zhou J, Gool JK, Bijlenga D, Lammers GJ, Fronczek R, Schinkelshoek MS (2024) Recent insights into the pathophysiology of narcolepsy type 1. Sleep Med Rev 78:101993. doi: 10.1016/j.smrv.2024.101993 PMID: 39241492

Objective: To focus on recent insights into Narcolepsy type 1 (NT1) pathophysiology, discussing structural and functional changes, immune system involvement, genetic findings, and future perspectives for the pathophysiology and treatment options.

Summary: Narcolepsy type 1 (NT1) is one of the central disorders of the hypersomnolence and results from hypocretin (Hcrt, also nown as orexin) deficiency in the brain. The development of HcrtR2-specific or dual HcrtR1 and HcrtR2 agonists, has shown promising results in pre-clinical and clinical trials. These agonists can potentially become the first drugs to directly target the Hcrt system and replace the shortage of Hcrt in NT1.

Usage: Hcrt-2 conjugated to the ribosome-inactivating toxic protein saporin (Orexin-SAP, Cat #IT-20) eliminated up to 90% of Hcrt neurons but also caused significant loss of neighboring neuronal cells, such as Melanin-concentrating hormone (MCH) neurons.

Related Products: Orexin-B-SAP (Cat. #IT-20)

Wang D, Wei SN, Zhang L, Lang ZC, Wang SN, Cheng B, Lu Y, Wang X, Wang W, Li FS, Zhang H (2024) Impaired basal forebrain cholinergic neuron gdnf signaling contributes to perioperative sleep deprivation–induced chronicity of postsurgical pain in mice through regulating cholinergic neuronal activity, apoptosis, and autophagy. CNS Nerusci Ther doi: 10.1111/cns.70147 PMID: 39639706

Objective: This study investigated the roles of lateral basal forebrain glial cell line–derived neurotrophic factor (GDNF). The authors researched GDNF and the associated signaling and cholinergic neuron activity, apoptosis, and autophagy dysfunction in sleep deprivation–induced increased risk of chronic postsurgical pain (CPSP) in mice.

Summary: Perioperative sleep deprivation promotes chronicity of postsurgical pain possibly through decreasing basal forebrain GDNF signaling and causing cholinergic neuronal apoptosis and autophagy dysfunction.

Usage: To ablate the basal forebrain cholinergic neurons, 0.4μg/μL of mu p75-SAP (IT-16) in 0.6μL phosphate-buffered saline was used 3 weeks before the Skin/Muscle Incision and Retraction modeling.

Related Products: mu p75-SAP (Cat. #IT-16)

Lewis RD, Keilholz AN, Smith CL, Burd EA, Nichols NL (2024) Spinal TNF-α receptor 1 is differentially required for phrenic long-term facilitation (pLTF) over the course of motor neuron death in adult rats. Front Physiol 15 doi: 10.3389/fphys.2024.1488951 PMID: 39703667

Objective: To study the impact motor neuron death has on the output of surviving phrenic motor neurons as well as the compensatory mechanisms that are recruited.

Summary: Results revealed that TNFR1 expression was increased on phrenic motor neurons of 28d CTB-SAP rats, and that astrocytes were increased and exhibited reactive morphology in the phrenic motor nucleus of CTB-SAP rats. This work suggests that TNFR1 could be used as a potential therapeutic agent in CTB-SAP rats and patients with respiratory motor neuron disease.

Usage: Intrapleural injection of CTB-SAP (25μg dissolved in PBS) to target respiratory motor neurons.

Related Products: CTB-SAP (Cat. #IT-14)

Morishata Y, Fuentes I, Gonzalez-Salinas S, Favate J, Mejaes J, Zushida K, Nishi A, Hevi C, Goldsmith N, Buyske S, Sillivan SE, Miller CA, Kandel ER, Uchida S, Shah P, Alarcon JM, Barker DJ, Shumyatsky GP (2024) Dopamine release and dopamine-related gene expression in the amygdala are modulated by the gastrin-releasing peptide in opposite directions during stress-enhanced fear learning and extinction. Molexular Psychiatry doi: 10.1038/s41380-024-02843-8 PMID: 39580604

Objective: To investigate neural circuits serving the dopamine function for fear extinction and PTSD.

Summary: Results demonstrate that gastrin-releasing peptide regulates dopamine function in stress-enhanced fear processing and identifies Grp as the first gene known to regulate dopaminergic control of fear extinction.

Usage: Bombesin-SAP (IT-40) or Blank-SAP (IT-21) (80 ng/µl) dissolved in saline were injected bilaterally into the basolateral amygdala (AP: -2.0 mm, ML: ±3.25 mm, DV: -4.3 mm) in 0.3 µl volume.

Related Products: Bombesin-SAP (Cat. #IT-40), Blank-SAP (Cat. #IT-21)

Ammar AO (2024) Involvement of peptidergic Edinger-Westphal nucleus in the neurobiology of migraine and acute alcohol exposure. Univ Pecs Thesis.

Objective: To confirm the role of Edinger-Westphal nucleus/urocortin1 (EWcp/UCN1) neurons in migraine. They hypothesized that selective ablation of EWcp/UCN1 neurons will influence the migraine-related behaviors induced by CGRP.

Summary: Upon selective ablation of EWcp/UCN1 neurons, authors examined the migraine-related behaviors in response to calcitonin gene-related peptide (CGRP) treatment. Leptin-SAP treatment significantly reduced the number of UCN1 immunoreactive neurons in the EWcp compared to naïve mice. Before ablation of EWcp/UCN1 neurons, CGRP treatment significantly reduced the periorbital withdrawal threshold compared to saline.

Usage: For selective UCN1 neuron ablation, 50 nl of Leptin-SAP was microinjected into the rostral and caudal parts of the EWcp area.

Related Products: Leptin-SAP (Cat. #IT-47)

Moreno-Rodríguez M, Martínez-Gardeazabal J, Bengoetxea de Tena I, Llorente-Ovejero A, Lombardero L, González de San Román E, Giménez-Llort L, Manuel I, Rodríguez-Puertas R (2024) Cognitive improvement via cortical cannabinoid receptors and choline-containing lipids. Br J Pharmacol doi: 10.1111/bph.17381 PMID: 39489624

Objective: Authors hypothesized that activation of the endocannabinoid system may confer neuroprotection against cholinergic degeneration.

Summary: Degeneration, induced by 192-IgG-saporin, of baso-cortical cholinergic pathways resulted in memory deficits and decreased cortical levels of lysophosphatidylcholines (LPC). The cannabinoid agonist WIN55,212-2 restored cortical cholinergic transmission and LPC levels via activation of cannabinoid receptors. This activation altered cortical lipid homeostasis mainly by reducing sphingomyelins in lesioned animals. These modifications were crucial for memory recovery.

Usage: Basal forebrain cholinergic degeneration was induced following bilateral stereotaxic injection of 192IgG-saporin (130 ng/μl, IT-01) into the nucleus basalis magnocellularis (NBM).

Related Products: 192-IgG-SAP (Cat. #IT-01)

Chuang KH, Zhou XA, Xia Y, Li z, Qian L, Eeles E, Ngiam G, Fripp J, Coulson EJ (2024) Cholinergic basal forebrain neurons regulate vascular dynamics and cerebrospinal fluid flux. bioRxiv 2024.08.25.609536. doi: 10.1101/2024.08.25.609536

Objective: To show that vascular-CSF coupling correlates with cortical cholinergic activity in non-demented aged humans.

Summary: Waste from the brain is cleared via a cerebrospinal fluid (CSF) exchange pathway. Problems in this pathway is suggested to underlie the pathogenesis of many brain conditions. Cerebrovascula oscillation that couples with pulsatile CSF inflow is suggested to drive the flow of fluid, however how this coupling is regulated in unlcear. The resultsfor the study suggest a neurovascular mechanism by which CSF/glymphatic flux is modulated by cholinergic neuronal activity, thereby providing a conceptual basis for the development of diagnostics and treatments for glymphatic dysfunction.

Usage: Injections of mu-p75-SAP (0.5 mg/ml, IT-16) or control Rabbit-IgG-SAP (0.5 mg/ml, IT-35) were performed into the border between the medial septum and ventral diagonal band. In the first study, the toxin was infused at a rate of 0.4 μl/min (1.5μl total volume), which resulted in a large amount of ablation. In the second study, the toxin concentration was reduced to 0.3 mg/ml to preserve more cholinergic neurons and was infused at a rate of 0.18μl/min (1.0μl total volume).

Related Products: mu p75-SAP (Cat. #IT-16), Rabbit IgG-SAP (Cat. #IT-35)

Jiang H, Cui H, Chen M, Li F, Shen X, Guo CJ, Hoekel GE, Zhu Y, Han L, Wu K, Holtzman MJ, Liu Q (2024) Divergent sensory pathways of sneezing and coughing. Cell 187(21):5981-5997. doi: 10.1016/j.cell.2024.08.009 PMID: 39243765

Objective: To study the difference in sensory receptors and neurotransmission/modulation mechanisms between sneezing and coughing.

Summary: Sneezing and coughing are frequently associated with allergies and respiratory viral infections and it’s assumed both involve common sensory receptors and neurotransmission mechanisms. The author’s work show that the nasal mucosa is innervated by several discrete populations of sensory neurons, but only one population (MrgprC11+MrgprA3−) mediates sneezing. Although this same population innervates the trachea, it does not mediate coughing, and instead, a distinct sensory population (somatostatin SST) mediates coughing but not sneezing. NMB-SAP was used to ablate neruomedin B (NMB) receptor expressing and nucleus tractus solitarius (NTS) neurons. Deletion of these neurons did not affect the coughing responses to Ly344864 and IL-31 (agonists to SST neurons) suggesting that NMB-sensitive NTS neurons do not mediate coughing.

Usage: Neuronal ablation by SST-saporin and NMB-saporin. SST-saporin was made by mixing biotin-labeled somatostatin and Streptavidin-ZAP (IT-27) at a 1:1 molar ratio at room temperature for 20 minutes. SST-Saporin (10 μM, 50 nL), NMB-saporin (#IT-70; 50 ng in 50 nL) or Blank-SAP (#IT-21; 10 μM in 50 nL or 50 ng in 50 nL) was injected into the NTS region.

Related Products: Streptavidin-ZAP (Cat. #IT-27), NMB-SAP (Cat. #IT-70), Blank-SAP (Cat. #IT-21)

Limonta P, Chiaramonte R, Casati L (2024) Unveiling the dynamic interplay between cancer stem cells and the tumor microenvironment in melanoma: Implications for novel therapeutic strategies. Cancers (Basel) 16(16):2861. doi: 10.3390/cancers16162861 PMID: 39199632

Objective: To review the bidirectional communication between melanoma cancer stem cells (CSCs) and the tumor microenvironment, highlighting its role in drug resistance and tumor relapse.

Summary: Melanoma CSCs evade immune surveillance and recruit immune cells with immunosuppressive and tumor-promoting properties, establishing a supportive microenvironment. They also transfer stemness and aggressive traits to neighboring non-CSCs, driving tumor progression and metastasis. Targeting these interactions may offer novel therapeutic strategies for combating melanoma.

Usage: This review publication highlights the usage of Anti-CD271-SAP and CD133-SAP in previous publications.

Related Products: ME20.4-SAP (Cat. #IT-15), Anti-CD133-SAP (Cat. #IT-82), Saporin (Cat. #PR-01)

See Also:

• Ngo M et al. Antibody therapy targeting CD47 and CD271 effectively suppresses melanoma metastasis in patient-derived xenografts. Cell Rep 16:1701-1716, 2016.
• Bostad M et al. Light-controlled endosomal escape of the novel CD133-targeting immunotoxin AC133-saporin by photochemical internalization – A minimally invasive cancer stem cell-targeting strategy. J Control Release 206:37-48, 2015.