saporin

Q: I read on your website that, “There are two types of RIPs: type I, which are much less cytotoxic due to the lack of the B chain and type II, which are distinguished from type I RIPs by the presence of the B chain and their ability to enter cells on their own.”

In the IT-27 Streptavidin-ZAP product, which type of saporin is there? Is it both type I and type II because the saporin is purified from the plant, or is it one specific type only in the product.

A: All saporin molecules are Type I ribosome-inactivating proteins. We only use saporin. An example of a Type II RIP is ricin, which can enter a cell on its own and has been used throughout history as a method of assassination.

Streptavidin-ZAP is streptavidin attached to saporin. On its own it has no way to get inside a cell. By mixing Streptavidin-ZAP with a biotinylated molecule that is recognized on the cell surface, the resulting conjugate is able to bind and internalize saporin into a cell. Once inside saporin inactivates the ribosomes which causes cell death.

Ardini M, Vago R, Fabbrini MS, Ippoliti R (2022) From immunotoxins to suicide toxin delivery approaches: Is there a clinical opportunity?. Toxins (Basel) 14(9):579. doi: 10.3390/toxins14090579 PMID: 36136517

Objective: To give an overview describing some of the bacterial and plant enzymes studied so far for their delivery and controlled expression in tumor models.

Summary: “Suicide gene” therapy (SGT), consists of the selective delivery of genes coding for toxic proteins, into target cancer cells. This new and promising approach may overcome some of the issues related to the use of chemical agents (chemotherapy) such as as specificity, high dosages with accompanying side effects, and chemoresistance induction.

Ryan Y, Harrison A, Trivett H, Hartley C, David J, Clark GC, Hiscox JA (2022) RIPpore: A novel host-derived method for the identification of ricin intoxication through oxford nanopore direct RNA sequencing. Toxins (Basel) 14(7):470. doi: 10.3390/toxins14070470

Objective: The Depurination event could be detected using Oxford Nanopore Technologies (ONT) direct RNA sequencing, detecting a change in charge in the ricin loop.

Summary: Collectively, this work highlights the potential for ONT and direct RNA sequencing to detect and quantify depurination events caused by ribosome-inactivating proteins such as ricin.

Usage: Saporin was added as described by Rust et al., at 100 nM [22] for 24 h.

Related Products: Saporin (Cat. #PR-01)

See Also:

• Rust A et al. Two complementary approaches for intracellular delivery of exogenous enzymes. Sci Rep 5:12444, 2015.

Li Y, Ye Z, Yang H, Xu Q (2022) Tailoring combinatorial lipid nanoparticles for intracellular delivery of nucleic acids, proteins, and drugs. Acta Pharm Sin B 12(6):2624-2639. doi: 10.1016/j.apsb.2022.04.013

Objective: To highlight the recent progress in combinatorial lipid nanoparticles (LNPs) with novel structures and properties for the delivery of small- and macromolecular therapeutics.

Summary: The administration of protein/LNP negatively impacted reproduction in rats, including sperm production, estrous cyclicity and testicular and ovarian morphology, without causing any significant side effects. This non-surgical approach can be developed into a safe and convenient strategy for controlling the overproduction of pet and wildlife.

Usage: Intravenous administration of saporin loaded LNPs

Related Products: Saporin (Cat. #PR-01)

Ancheta LR, Shramm PA, Bouajram R, Higgins D, Lappi DA (2022) Saporin as a commercial reagent: its uses and unexpected impacts in the biological sciences-tools from the plant kingdom. Toxins (Basel) 14(3):184. doi: 10.3390/toxins14030184

Read complete article.

Xu L, Füredi N, Lutter C, Geenen B, Pétervári E, Balaskó M, Dénes Á, Kovács KJ, Gaszner B, Kozicz T (2022) Leptin coordinates efferent sympathetic outflow to the white adipose tissue through the midbrain centrally-projecting Edinger-Westphal nucleus in male rats. Neuropharmacology 205:108898. doi: 10.1016/j.neuropharm.2021.108898

Objective: To show that leptin bound to neurons of the Edinger-Westphal nucleus (EWcp) stimulated STAT3 phosphorylation and increases urocortin 1 (Ucn1)-production in a time-dependent manner.

Summary: EWcp/LepRb/Ucn1 neurons respond to leptin signaling as well as control white adipose tissue size and fat metabolism without altering food intake.

Usage: Ablation of EWcp leptin receptor (LepRb) positive neurons with leptin-saporin. Either unconjugated saporin (53 ng in 80 nl MQ, or Leptin-SAP (90 ng in 80 nl MQ, was injected into the rat midbrain.

Related Products: Leptin-SAP (Cat. #IT-47), Saporin (Cat. #PR-01)

Mitdank H, Tröger M, Sonntag A, Shirazi NA, Woith E, Fuchs H, Kobelt D, Walther W, Weng A (2022) Suicide nanoplasmids coding for ribosome-inactivating proteins. Eur J Pharm Sci 170:106107. doi: 10.1016/j.ejps.2021.106107

Objective: To investigate the anti-proliferative activity of suicide-nanoplasmids.

Summary: In an in vivo neuroblastoma tumor model, treated mice showed a reduced tumor growth.

Usage: Design of a suicide nanoplasmid vector with saporin.

Related Products: Saporin (Cat. #PR-01)

Ujvári B, Pytel B, Márton Z, Bognár M, Kovács LÁ, Farkas J, Gaszner T, Berta G, Kecskés A, Kormos V, Farkas B, Füredi N, Gaszner B (2022) Neurodegeneration in the centrally-projecting Edinger-Westphal nucleus contributes to the non-motor symptoms of Parkinson’s disease in the rat. J Neuroinflammation 19(1):31. doi: 10.1186/s12974-022-02399-w

Objective: To investigate whether neuron loss and alpha-synuclein accumulation in the urocortin 1 containing (UCN1) cells of the centrally-projecting Edinger-Westphal (EWcp) nucleus is associated with anxiety and depression-like state in the rat.

Summary: Neurodegeneration of urocortinergic EWcp contributes to the mood-related non-motor symptoms in toxic models of Parkinson’s disease in the rat.

Usage: Leptin-SAP or unconjugated Saporin (0.08 μl) was injected into the EWcp area. This selective ablation of UCN1 neurons was used to validate the depression-like phenotype in rats. Behavioral, functional–morphological, biochemical and histopathological tools were used to test the motor coordination, mood status as well as morphological changes in the brain.

Related Products: Saporin (Cat. #PR-01), Leptin-SAP (Cat. #IT-47)

Hickerson BT, Daniels-Wells TR, Payes C, Clark LE, Candelaria PV, Bailey KW, Sefing EJ, Zink S, Ziegenbein J, Abraham J, Helguera G, Penichet ML, Gowen BB (2022) Host receptor-targeted therapeutic approach to counter pathogenic New World mammarenavirus infections. Nat Commun 13(1):558. doi: 10.1038/s41467-021-27949-3

Objective: Demonstrate that a fusion protein of the antibody (ch128.1/IgG1) directed against the apical domain of human transferrin receptor 1 (hTfR1) and the Machupo virus (MACV) can inhibit infection of attenuated and pathogenic New World mammarenaviruses (NWMs).

Summary: NWMs cause life-threatening hemorrhagic fever (HF) and these viruses enter into cells via hTfR1. Use of ch128.1/IgG1 with other promising direct-acting small molecule antivirals or antibodies targeting the viral envelope glycoprotein would provide a complementary therapeutic strategy that would increase efficacy and reduce the emergence of drug resistance.

Usage: References MonoBiotin-ZAP reacted with avidinylated anti-hTfR (ch128.1Av) in a 1:1 molar ratio on ice for 30 minutes.

Related Products: MonoBiotin-ZAP (Cat. #BT-ZAP)

See Also:

• Daniels-Wells TR et al. Insights into the mechanism of cell death induced by saporin delivered into cancer cells by an antibody fusion protein targeting the transferrin receptor 1. Toxicol In Vitro 27(1):220-231, 2013.
• Daniels TR et al. Conjugation of an anti transferrin receptor IgG3-avidin fusion protein with biotinylated saporin results in significant enhancement of its cytotoxicity against malignant hematopoietic cells. Mol Cancer Ther 6:2995-3008, 2007.

Joshi BS, Ortiz D, Zuhorn IS (2021) Converting extracellular vesicles into nanomedicine: loading and unloading of cargo. Materials Today Nano 16:100148. doi: 10.1016/j.mtnano.2021.100148

Objective: To provide a comprehensive overview of (i) methods for the loading of EVs with therapeutic cargo, (ii) methods for EV surface functionalization to direct EVs to target cells, and (iii) methods to stimulate cargo release from EVs.

Summary: Development of methodologies to offload the natural cargo of EVs and substitute it for a cargo of interest, i.e., similar to the generation of empty viral capsids, may further aid in higher loading efficiency and enhanced therapeutic effects with improved safety.

Usage: Saporin, a small (30 kDa) ribosome-inactivating protein that induces cytotoxicity by inhibiting protein synthesis,was successfully loaded into EVs by electroporation.

Related Products: Saporin (Cat. #PR-01)

See Also:

• Nakase I Intracellular delivery methods using biofunctional peptide-modified extracellular vesicles. Extracell Vesicles Circ Nucleic Acids 1:44, 2020. American Society for Exosomes and Microvesicles 2020 Annual Meeting

Wu B, Zhao TV, Jin K, Hu Z, Abdel MP, Warrington KJ, Goronzy JJ, Weyand CM (2021) Mitochondrial aspartate regulates TNF biogenesis and autoimmune tissue inflammation. Nat Immunol 22(12):1551-1562. doi: 10.1038/s41590-021-01065-2

Objective: To identify a deficiency of mitochondrial aspartate production as a key abnormality in autoimmune T cells.

Summary: Shortage of mitochondrial aspartate disrupted the regeneration of the metabolic cofactor nicotinamide adenine dinucleotide (NAD), causing ADP-deribosylation of the endoplasmic reticulum (ER) sensor GRP78/BiP. Transfer of intact mitochondria into T cells as well as supplementation of exogenous aspartate rescued the mitochondria-instructed expansion of ER membranes and suppressed TNF release and rheumatoid tissue inflammation.

Usage: Immunofluorescence (Permeabilization by 0.5% Saporin)

Related Products: Saporin (Cat. #PR-01)

Illath K, Kar S, Gupta P, Shinde A, Wankhar S, Tseng FG, Lim KT, Nagai M, Santra TS (2022) Microfluidic nanomaterials: From synthesis to biomedical applications. Biomaterials 280:121247. doi: 10.1016/j.biomaterials.2021.121247

Objective: To evaluate the current state of the controlled synthesis of nanomaterials using microfluidic devices.

Summary: In summary, inherent features of microfluidics enabled the controlled synthesis of biopolymer and silica nanomaterials that can easily encapsulate drugs.

Usage: Saporin was loaded quickly with nanogel of various sizes and observed that saporin loaded protein releasing depended on the density of cross-linking.

Related Products: Saporin (Cat. #PR-01)

Shramm PA, Ancheta LR, Bouajram R, Lappi DA (2021) A brief history of saporin and its contributions to neuroscience. Neuroscience 2021 Abstracts J002.11. Society for Neuroscience, Virtual.

Summary: When investigating the origins of targeted toxins (a drug, therapy, or scientific tool directed to a unique extracellular target), an appropriate place to begin is with the Nobel Prize-winning work of Paul Ehrlich and his concept of the “magic bullet.” Over 100 years later, the use of targeted toxins to perform molecular neurosurgery has become a vital practice that allows researchers to observe changes in organisms after eliminating a neuronal population. A prime example of this practice is the specific targeting of cholinergic neurons in the basal forebrain to mimic Alzheimer’s disease (AD). The research tool designed for this purpose is 192-IgG-Saporin, an antibody conjugated to the ribosome-inactivating protein (RIP) Saporin. Researchers have used this targeted toxin for over 30 years. A 2019 publication by Verkhratsky et al. reviews AD models and states this is the only lesion model that specifically targets cholinergic neurons. In 1983, during a quest to find the optimal payload for a targeted toxin, Fiorenzo Stirpe and colleagues discovered Saporin, a plant protein isolated from the common soapwort plant Saponaria officinalis. Unlike ricin and abrin, Saporin does not have a binding chain and cannot enter a cell on its own. Scientists have devised new ways to use Saporin to advance their research and drug development activities. Just a few examples include: 1. A novel suicide gene therapy approach that uses a vector encoding a double-stranded DNA aptamer to deliver the gene encoding Saporin, 2. Delivery of Saporin encapsulated in a nanotechnology system for development of cancer treatments, 3. A deeper understanding of the difference between pain and itch and the relevant pathways, and 4. Development of a stable epilepsy animal model that is used for screening specific treatments that will lead to micro-methods to eliminate the disease. This review will focus on Saporin as the payload delivered to cells. Targeted toxins (typically targeted by an antibody or peptide chemically linked or genetically fused) provide robust tools for neuroscience where ablation of specific neuronal populations is used to study behavior and function. Saporin is an ideal molecule because of its extreme resistance to high temperatures and denaturation, retention of catalytic activity after conjugation, and lack of a binding chain to allow entrance to the cytoplasm of cells on its own. As a result, it is one of the most studied RIPs used for its vigorousness, potency, safety, and ease of use in the laboratory. The information presented will shed light on the history of Saporin, current applications, and what the future holds for this protein in the neuroscience field.

Related Products: Saporin (Cat. #PR-01)

View the complete poster.

Chen X, Liu H, Li A, Ji S, Fei H (2021) Hydrophobicity-tuned anion responsiveness underlies endosomolytic cargo delivery mediated by amphipathic vehicle peptides. J Biol Chem 297(6):101364. doi: 10.1016/j.jbc.2021.101364

Objective: The study focuses on hydrophobicity and a structure-function strategy to evolve a template peptide for endosomolytic cargo delivery.

Summary: The peptide LP6 could dramatically promote cargo cell entry and facilitate cytosolic delivery of biomacromolecules such as saporin.

Usage: HeLa cells were treated with saporin (10, 20, 50μg/ml) in the absence (–) or presence (+) of LP6 (20μM) to confirm the cytosolic delivery ability of LP6.

Related Products: Saporin (Cat. #PR-01)

Lodhi MS, Khan MT, Bukhari SMH, Sabir SH, Samra ZQ, Butt H, Akram MS (2021) Probing transferrin receptor overexpression in gastric cancer mice models. ACS Omega 6(44):29893-29904. doi: 10.1021/acsomega.1c04382

Objective: To investigate the role of the transferrin receptor, a glycoprotein receptor that is expressed many-folds on rapidly growing cells due to the greater demand of iron, in gastric cancer.

Summary: A mouse model of gastric cancer has the potential to be used in the future to study the therapeutic effects of cancer medicines, and overexpression of transferrin receptors could be identified through the designed probe to be used as diagnostics.

Related Products: MonoBiotin-ZAP (Cat. #BT-ZAP)

See Also:

• Daniels TR et al. Conjugation of an anti transferrin receptor IgG3-avidin fusion protein with biotinylated saporin results in significant enhancement of its cytotoxicity against malignant hematopoietic cells. Mol Cancer Ther 6:2995-3008, 2007.

Borkowski LF, Smith CL, Keilholz AN, Nichols NL (2021) Divergent receptor utilization is necessary for phrenic long-term facilitation over the course of motor neuron loss following CTB-SAP intrapleural injections. J Neurophysiol 126(3):709-722. doi: 10.1152/jn.00236.2021

Objective: The authors tested the hypothesis that phrenic long-term facilitation (pLTF) following treatment with CTB-SAP is: 1) adenosine 2A (A2A) receptor-dependent at 7d; and 2) serotonin (5-HT) receptor-dependent at 28d.

Summary: This study furthers understanding of the contribution of differential receptor activation to pLTF and its implications for breathing following respiratory motor neuron death.

Usage: Male rats received bilateral, intrapleural injections of CTB-SAP or Saporin Control (25 μg).

Related Products: CTB-SAP (Cat. #IT-14), Saporin (Cat. #PR-01)

Dai M, Nakamura S, Takahashi C, Sato M, Munetomo A, Magata F, Uenoyama Y, Tsukamura H, Matsuda F (2021) Reduction of arcuate kappa-opioid receptor-expressing cells increased luteinizing hormone pulse frequency in female rats. Endocr J 68(8):933-941. doi: 10.1507/endocrj.EJ20-0832

Summary: The number of Kiss1-expressing cells in the ARC was not affected by ARC Dyno-SAP treatment. Dynorphin-Kappa opioid receptor (KOR) signaling within the ARC seems to mediate the suppression of the frequency of pulsatile GnRH/LH release, and neurons in the hypothalamic arcuate nucleus (ARC) non-KNDy KOR neurons may be involved in the mechanism modulating GnRH/LH pulse generation.

Usage: Female rats were stereotaxically injected with Dyno-SAP (20 ng/200 nL) or unconjugated Saporin (18.6 ng/200 nL) as a control, bilaterally into the anterior and posterior ARC (total of 4 injection sites).

Related Products: Dyno-SAP (Dynorphin-SAP) (Cat. #IT-68), Saporin (Cat. #PR-01)

Marques SM, Naves LM, Silva TME, Cavalcante KVN, Alves JM, Ferreira-Neto ML, de Castro CH, Freiria-Oliveira AH, Fajemiroye JO, Gomes RM, Colombari E, Xavier CH, Pedrino GR (2021) Medullary noradrenergic neurons mediate hemodynamic responses to osmotic and volume challenges. Front Physiol 12:649535. doi: 10.3389/fphys.2021.649535

Summary: The study sought to determine the role of noradrenergic neurons in hypertonic saline infusion (HSI)-induced hemodynamic recovery. Findings show that together the A1 and A2 neurons are essential to HSI-induced cardiovascular recovery in hypovolemia.

Usage: Medullary catecholaminergic neurons were lesioned by nanoinjection of Anti-DBH-SAP (0.105 ng·nl−1) into A1, A2, or both (LES A1; LES A2; or LES A1+A2, respectively). Sham rats received nanoinjections of unconjugated saporin in the same regions.

Related Products: Anti-DBH-SAP (Cat. #IT-03), Saporin (Cat. #PR-01)

Liu Y, Forsythe P (2021) Vagotomy and insights into the microbiota-gut-brain axis. Neurosci Res 168:20-27. doi: 10.1016/j.neures.2021.04.001

Objective: To review the use of vagotomy as a tool to explore the role of the vagus nerve in gut to brain signaling.

Summary: This review article is a summary of the knowledge gained from vagotomy, a surgical procedure that involves removing part of the vagus nerve. The article discusses using CCK-SAP to specifically ablate afferent vagal nerves in the gastrointestinal tract.

Usage: The article references a study by Diepenbroek et al. that used CCK-SAP in the following dosages: In vitro: each well was treated with a different dose of saporin conjugates (0, 2.4, 24, or 240 ng) for 24 h. In vivo: An equal volume (rat: 1 µl; mouse: 0.5 µl) of CCK-SAP (250 ng/µl) or Saporin (250 ng/µl) was injected at two sites rostral and caudal to the laryngeal nerve branch.

Related Products: CCK-SAP (Cat. #IT-31), Saporin (Cat. #PR-01)

See Also:

• Diepenbroek C et al. Validation and characterization of a novel method for selective vagal deafferentation of the gut. Am J Physiol Gastrointest Liver Physiol 313:G342-G352, 2017.

Andriessen AS, Donnelly CR, Ji RR (2021) Reciprocal interactions between osteoclasts and nociceptive sensory neurons in bone cancer pain. Pain Rep 6(1):e867. doi: 10.1097/PR9.0000000000000867

Summary: Current pharmacotherapies available for bone cancer pain are insufficient to provide safe and efficacious pain relief. The authors discuss the mechanisms used by cancer cells within the bone tumor microenvironment (TME) to drive bone cancer pain.

Usage: Microglial ablation using Mac-1-SAP (15 μg in 8.8 μl i.t.) and Saporin control (Cat. #PR-01, 8.8 μg in 8.8 μl), is sufficient to attenuate nerve injury-induced pain in male, but not female mice.

See: Sorge R et al. Different immune cells mediate mechanical pain hypersensitivity in male and female mice. Nat Neurosci 18:1081-1083, 2015.

Related Products: Mac-1-SAP mouse/human (Cat. #IT-06), Saporin (Cat. #PR-01)