References

Keilholz AN, Lopez S, Attari M, Nguyen NP, Henry J, Smith CL, Feldberg A, Osman KL, Golzy M, Bunyak F, Lever TE, Nichols NL (2026) Impact of tongue exercise on hypoglossal axis survival, structure, and output in a rodent model of hypoglossal motor neuron degeneration. J Neurophysiol doi: 10.1152/jn.00631.2024 PMID: 42012472

Objective: To investigate the effects of a high-repetition/low-resistance tongue exercise paradigm on XII axis survival, structure, and output in adult male Sprague Dawley rats.

Summary: Intralingual injections of CTB-SAP result in decreased XII motor neuron survival and degenerative changes in the XII nerve consistent with what is seen in many motor neuron diseases. While these deficits are not mitigated by tongue exercise, the authors observed increased microglial fractional area/density in the XII nucleus of CTB-SAP + exercise rats.

Usage: Rats received intralingual injection of either CTB-SAP (IT-14) or unconjugated CTB + SAP (PR-01).

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

Yao Z, Shi Z, Hu P, Wang C, Wang H (2026) Visualization of endosomal escape of intracellularly delivered protein with unexpected photochemical internalization of trypan blue. Adv Sci (Weinh) e16456. doi: 10.1002/advs.202516456 PMID: 41961480

Objective: To demonstrate trypan blue as a simple yet powerful tool for advancing intracellular protein delivery and tracking.

Summary: Upon 590 nm light irradiation, trypan blue (TB) acts as a photosensitizer, triggering photochemical internalization (PCI) that promotes endosomal escape and protein release into the cytosol, accompanied by recovery of GFP fluorescence. This TB-mediated PCI not only enhances delivery efficiency but also allows real-time visualization of protein binding and release.

Usage: 143B cells were treated with Saporin, M2/Saporin, and M2/TB/Saporin at different Saporin concentrations, with or without light irradiation.

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

Babatunde OO, Bibby MG, Atala A, Almeida-Porada G, Porada CD (2026) In utero HSC transplantation for sickle cell disease: A potential therapeutic approach that overcomes complications of current therapies. Prenat Diagn doi: 10.1002/pd.70142 PMID: 41936060

Objective: To examine current evidence and recent advances for treatment of sickle cell disease (SCD).

Summary: Biotinylated anti‐c‐kit/CD117 mAb coupled to a streptavidin‐conjugated saporin has been used to selectively deplete host HSC while preserving the host’s immune system. A single intravenous dose of the anti‐CD45‐saporin ADC enabled > 90% donor (congenic) hematopoietic engraftment and full correction of the SCD phenotype.

Related Products: Anti-CD117-SAP (Cat. #IT-83), Streptavidin-ZAP (Cat. #IT-27), Anti-CD45.2-SAP (Cat. #IT-91)

Serambeque B, Dias I, Mestre C, Marto CM, Botelho MF, Carvalho MJ, Laranjo M (2026) Photodynamic therapy-based strategies targeted at cancer stem cells: A scoping review. Cancers (Basel) 18(7):1162. doi: 10.3390/cancers18071162 PMID: 41976384

Objective: To examine strategies for targeting cancer stem cells using photodynamic therapy.

Summary: Photochemical internalization (PCI) is a widely adopted approach for targeting surface markers on cancer stem cells. Anti-CD133-SAP was evaluated in colorectal cancer, breast cancer, and melanoma. In CD133high colorectal cancer cells (WiDr), PCI with picomolar concentrations of AC133–saporin completely inhibited viability and colony formation, with no toxicity observed in the absence of light activation. Similar efficacy was observed in CD133+ breast (MDa-MB-231) and CD133high melanoma cells (FMEX-1) but not in CD133− breast cancer cells (MCF7), confirming target specificity. A similar strategy was employed to target CD44 in human cancer cell lines.

Related Products: Anti-CD133-SAP (Cat. #IT-82), Anti-CD44-SAP (Cat. #IT-72), Streptavidin-ZAP (Cat. #IT-27)

Cardani S, Janes TA, Asif R, Pagliardini S (2026) Sex differences in the effects of etonogestrel on respiratory recovery in an in vivo rat model of central chemoreflex impairment. Acta Physiol (Oxf) 242(4):e70194. doi: 10.1111/apha.70194 PMID: 41823358

Objective: Chronic etonogestrel (ETO) treatment improved the CO2 chemoreflex in female rats in which <80% of chemoreceptor neurons comprising the retrotrapezoid nucleus (RTN) were eliminated. Since the progesterone receptor is widely expressed in both the male and female brain, authors investigated the effects of ETO on respiratory recovery.

Summary: Authors used SSP-SAP to partially eliminate RTN neurons. Dose-dependent impairment of the CO2 chemoreflex in both sexes following chemoreceptor lesion corroborates the findings that ETO treatment restores ventilation in female rats with moderate-sized lesions.

Usage: Four microinjections (150 nL per injection) were made with Substance P-conjugated saporin toxin (SSP-SAP, IT-11) and fluorescent carboxylate-modified Fluospheres TM to label injection sites.

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

Lim-Paik C, Zeng Q, Beyea R, Boohaker R, Wang P (2026) Improving cytotoxicity of saporin with saponin SO1406 isolated from the roots of saponaria officinalis. Biomedicines 14(3):626. doi: 10.3390/biomedicines14030626

Objective: To identify structurally defined novel natural saponins and evaluate their ability to enhance anticancer cytotoxicity.

Summary: Saponins have recently emerged as promising natural products that enhance toxin-based anticancer therapeutics by improving cytosol uptake. Among the isolated compounds, SO1684 is a known saponin and SO1406 exhibited the most pronounced biological activity, significantly enhancing the cytotoxicity of the ribosome-inactivating protein saporin in the MDA-MB231 (triple-negative breast cancer) cell line.

Usage: Cells were treated with 50 mL of saporin

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

Hamakubo S, Komatsu N, Kosai A, Kuroda M, Sawada M, Shimizu R, Ohashi R, Suenaga H, Hamakubo T, Abe T (2026) Enhanced antitumor efficacy of a combination of immunotoxin and photosensitizer under illumination in xenograft mice. Biomedicines 14:573. doi: 10.3390/biomedicines14030573

Objective: To investigate the in vivo therapeutic efficacy of intelligent Targeted Antibody Phototherapy (iTAP), utilizing light as a spatiotemporal trigger to promote the cytoplasmic release of toxins.

Summary: The authors investigated the in vivo therapeutic efficacy of iTAP using an EGFR-targeted IT composed of cetuximab conjugated to saporin (IT-Cmab), administered in combination with the clinically used photodynamic therapy (PDT) photosensitizer NPe6, in a xenograft mouse model. Findings indicate that iTAP represents a promising therapeutic strategy for HNSCC.

Usage: Biotinylated Cmab was mixed with streptavidin-saporin (IT-Cmab). Mice received intraperitoneal IT-Cmab (0.5 mg/kg), followed 72 h later by intravenous NPe6 (5 mg/kg).

Related Products: Streptavidin-ZAP (Cat. #IT-27)

Wang W, Zhang Y, Li L, Xu Y, Zhang W, Chen X, Wang X, Tong G, Zhang P (2026) PACAP/PAC 1 modulates light-induced sleep via the ipRGC-VLPO pathway. Biochem Biophys Res Commun 808:153462. doi: 10.1016/j.bbrc.2026.153462 PMID: 41702189

Objective: To investigate the mechanism of PACAP in ipRGC–VLPO light-induced sleep.

Summary: Partial ablation of ipRGCs by Melanopsin-SAP reduced light-induced sleep duration, whereas PACAP 1-38 administration reversed this effect, leading to an increase in REM sleep. After the partial destruction of ipRGCs through the intraocular injection of saporin (SAP), we continued to observe the effect of PACAP on light-induced sleep. The results showed that after the microdialysis injection of PACAP 1-38 into the VLPO of SAP mice, the light-induced sleep of the mice increased; specifically, REM sleep significantly increased. The results suggest that PACAP is involved in ipRGC–VLPO-mediated light-induced sleep.

Related Products: Melanopsin-SAP (Cat. #IT-44)

Yang Y, Jia H, Yang L, He B, Zhang K, Liu H (2026) An AIEgen-based carrier enables efficient cytosolic delivery of bioactive proteins. Int J Nanomedicine 21:1-14. doi: 10.2147/IJN.S557672

Summary: The authors report a novel AIEgen (Aggregation-induced emission luminogen) -based carrier, MTPABP-Guided-Intracellular-Carrier (MAGIC), that achieves high efficiency in delivering native proteins into the cytosol. MAGIC efficiently delivered trypsin, RNase A, and saporin into the cytosol of mammalian cell lines while preserving their enzymatic or functional activity. The MAGIC delivery system holds significant promise for advancing the study of cellular physiology and enabling precise therapeutic interventions.

Usage: HeLa cells were treated with MTPABP/saporin complexes. Saporin concentration was 5 μg/mL. Free saporin served as a control.

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

Spedding M (2025) Does amyotrophic lateral sclerosis (als) have metabolic causes from human evolution?. Cells 14(21):1734. doi: 10.3390/cells14211734 PMID: 41227379

Objective: To evaluate if recent human genetic variants play major roles in Amyotrophic Lateral Sclerosis (ALS), changing metabolism.

Summary: The authors reviewed Cholera Toxin B (CTB) binding as a tool to study GM1 and fucosylated structures, and to cause denervation. Findings suggest CTB may be used as a surrogate marker of GM1. CTB-SAP causes specific motor neuron death, presumably by binding to and downregulating GM1, and possibly other fucosylated targets; powerful evidence linking loss of GM1 to denervation in ALS.

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

See Also:

• Llewellyn-Smith IJ et al. Tracer-toxins: cholera toxin B-saporin as a model. J Neurosci Methods 103(1):83-90, 2000.
• Ciuro M et al. Mitigating the functional deficit after neurotoxic motoneuronal loss by an inhibitor of mitochondrial fission. Int J Mol Sci 25(13):7059, 2024.
• Gulino R et al. Neuromuscular plasticity in a mouse neurotoxic model of spinal motoneuronal loss. Int J Mol Sci 20(6):1500, 2019.
• Lind LA et al. Hypoglossal motor neuron death via intralingual CTB-saporin (CTB-SAP) injections mimic aspects of amyotrophic lateral sclerosis (ALS) related to dysphagia. Neuroscience 390:303-316, 2018.
• Lewis RD et al. 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, 2024.
• Chew C et al. Exercise is neuroprotective on the morphology of somatic motoneurons following the death of neighboring motoneurons via androgen action at the target muscle. Dev Neurobiol 81(1):22-35, 2021.
• Chew C et al. Exercise is neuroprotective on the morphology of somatic motoneurons following the death of neighboring motoneurons via androgen action at the target muscle. Dev Neurobiol 81(1):22-35, 2021.
• Lind LA et al. Tongue and hypoglossal morphology after intralingual cholera toxin B-saporin injection. Muscle Nerve 63(3):413-420, 2021.
• Keilhoz A et al. Tongue exercise ameliorates structural and functional upper airway deficits in a rodent model of hypoglossal motor neuron loss. Front Neurol 15:1441529, 2024.