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.
Gao JL, Li Z, Calderon-Perez R, Pavek A, Kim L, McDermott DH, Murphy PM (2026) Gene therapy via CRISPR/Cas9-mediated Cxcr4 disease allele inactivation reverses leukopenia in WHIM mice. J Clin Invest 136(5):e202073. doi: 10.1172/JCI202073 PMID: 41505207
Objective: To provide proof of principle that CRISPR/Cas9-mediated inactivation of the Cxcr4 disease allele, combined with nongenotoxic HSC- targeted conditioning, may offer a safe and effective gene therapy strategy generalizable to all WHIM-causing mutations.
Summary: Warts, hypogammaglobulinemia, infections, and myelokathexis (WHIM) syndrome is an immunodeficiency caused by autosomal dominant hyperfunctional mutations in chemokine receptor CXCR4 that promote panleukopenia due to BM retention. The authors modified their previous protocol by adding conditioning with a nongenotoxic CD117-targeted immunotoxin, CD117-antibody-saporin-conjugate.
Gupta S (2026) Modelling Temporal Lobe Epilepsy with Sclerosis in the SSP-Saporin ‘Trojan Horse’ Model. Univ Calgary Thesis.
Objective: To confirm that the SSP-SAP model reproduces the defining features of human TLE and that a primary and selective GABAergic defect is sufficient to trigger epileptogenesis that results in TLE-HS+.
Summary: The author hypothesized that intrahippocampal SSP-SAP administration will first cause rats to exhibit reactive behavioural seizures, followed by self-generated epileptiform activity that will develop into electrographic seizures. Rats will also develop TLE anatomically characterized by progressive principal cell loss and astrogliosis.
Usage: Rats were stereotaxically injected with 150 nL of SSP-SAP (IT-11, 0.04 ng/nL) at 4 sites in the hippocampus.
McCallum S, Suresh KB, Islam TS, Tripathi MK, Saustad AW, Shelest O, Patil A, Lee D, Kwon B, Leitholf K, Yenokian I, Shaka SE, Beveridge CH, Manchandra P, Randolph CE, Meares GP, Dutta R, Plummer J, Calsavara VF, Kawaguchi R, Knott SRV, Chopra G, Burda JE (2026) Lesion-remote astrocytes govern microglia-mediated white matter repair. Nature 649(8098):959-970. doi: 10.1038/s41586-025-09887-y PMID: 41407858
Objective: To investigate Lesion-remote astrocytes (LRAs) from spared regions of mouse spinal cord following traumatic spinal cord injury.
Summary: The nature of astrocyte-extrinsic mechanisms that trigger discrete reactivity states are not well understood. Using Ccn1 expression as a biomarker of a molecularly distinct white matter LRA reactivity state, the authors explored the mechanism of its induction. IB4-SAP and CTB-SAP were injected in mice to selectively degenerate myelinated or non-myelinated sensory afferents, respectively.
Usage: 8 μg (10μl of 0.8 μg μl−1 in PBS) of Saporin (PR-01), IB4-SAP (IT-10) or CTB-SAP (IT-14) was injected subcutaneously into the plantar surface of the left hindpaw foot pad using a 30G insulin syringe.
Today’s topic is time-course for our saporin conjugates. Common questions we get are (1) how long does it takes to see cell death, (2) how long should I wait before performing histology on an animal, or (3) how long before I see behavioral changes in an animal?
In this image from Mantyh et. al. (1997), we are looking at confocal imagery of the binding and internalization of our peptide conjugate SP-SAP to the NK1r receptor in primary cultures of neonatal spinal cord neurons.
As you can see, conjugate binding occurs immediately where within hours, the SP-SAP has recognized and bound to the NK1 receptor. Here we see the areas of concentrated NK1R expression marked by yellow immunofluorescence.
But how long until you see cell death? Here is a cytotoxicity graph of in vitro data of our antibody conjugate 192-IgG-SAP. These are typical data after cells have been treated for 3 days, which is standard protocol.
Waite et al. (1994) used 192-IgG-SAP and showed the appearance of behavioral effects associated with neuronal loss at day four and plateauing at day 7.
This coincides with the time course seen in vitro. At this point, microglia will infiltrate, but stop at 7 days, which is probably the peak day for infiltration. Once there is complete removal of the detritus, microglia down-regulate and at 14 days all debris is cleared and the animal begins to regain normal eating and sleeping habits. This is the idea behind waiting about 2 weeks before performing histology.
Milanowski J, Pawłowska M, Woźniak A, Szewczyk-Golec K (2025) Summarizing the role of selected adipokines in parkinson’s disease: What is known about leptin, adiponectin, resistin, visfatin, and progranulin in neurodegeneration?. Molecules 30(22):4431. doi: 10.3390/molecules30224431 PMID: 41302488
Objective: To summarize current evidence and identify potential targets for Parkinson’s disease (PD) treatment or as biomarkers of disease progression.
Summary: The improper secretion and function of leptin have been associated with carcinogenesis and obesity and have also been implicated in neurodegeneration and PD. The administration of Leptin-SAP, to eliminate cells that recognize and internalize leptin, thereby inducing cell ablation, resulted in an increase in anhedonia and signs of anxiety in the rats. However, the procedure did not affect the rats’ motor abilities. Injection led to a decrease in EWcp/UCN1 cells, suggesting neurodegeneration.
Yu C, Li M, Shen F, Gao S, Wang J, He C, Wang L, Wu Y, Du Y (2025) Electroacupuncture alleviates cognitive impairments in APP/PS1 mice via gastric vagal afferent-mediated activation of the nucleus tractus solitarius‒locus coeruleus noradrenergic circuit. Chin Med 20(1):188. doi: 10.1186/s13020-025-01230-x PMID: 41233833
Objective: To demonstrate efficacy in ameliorating Alzheimer’s disease (AD)-related cognitive dysfunction through dual peripheral and central anti-infammatory actions using electroacupuncture (EA).
Summary: Transgenic mice were administrated with EA stimulation and cognitive function was assessed via the Morris water maze and novel object recognition tests. EA at ST36 and ST37 attenuated hippocampal synaptic ultrastructural degeneration. The experimental blockade of vagal aferent neurons via CCK-SAP injection into the nodose ganglion abolished the benefits induced by EA, directly implicating GVAF signaling in the improvement of EA-mediated AD.This intervention suppressed proinflammatory cytokines expression (IL-6, IL-1β, TNF-α) and microglial hyperactivation, effectively rescuing cognitive deficits in AD models.
Usage: CCK-SAP was injected into the nodose ganglion.
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.
Doyle S, Doran MM, Cunningham C, Lowry JP (2025) Real-time in vivo monitoring of cholinergic neurotransmission in the mouse brain using a microelectrochemical choline biosensor. Eur J Neurosci 62)9):e70291. doi: 10.1111/ejn.70291 PMID: 41185145
Objective: To refine an established choline oxidase (ChOx) microelectrochemical biosensor to validate its use for long-term recording in the freely moving mouse.
Summary: Systemic administration of donepezil produced a pronounced decrease in current in both the pre-frontal cortex and hippocampus, with scopolamine and amphetamine resulting in signal increases that were not observed in animals with selective saporin lesioning (mu p75-SAP) of the cholinergic basal forebrain. Furthermore, continuous biosensor recording in both regions displayed diurnal oscillations across repetitive light–dark phases. All are consistent with successful monitoring of endogenous changes in cholinergic neurotransmission.
Usage: Two 1-μL icv injections of either sterile PBS (control animals) or mu p75-SAP (IT-16) at a concentration of 0.6 μg/μL were made into the lateral ventricles usinga NanoFil syringe under the control of an infusion pump at a rate of 0.2 nL/min. Following injection, the needle tip was left in place for 8 min to minimize reflux.
Objective: To develop and validate a modular streptavidin based antibody drug conjugate platform for optimizing antibody mediated hematopoietic stem cell transplant conditioning.
Summary: The authors demonstrate that a streptavidin drug conjugate system enables rapid comparison of antibody payload combinations for hematopoietic stem cell depletion and leukemia targeting. The study builds on prior work using CD45 targeted immunotoxins to achieve effective hematopoietic niche depletion in murine HSCT models.
Usage: This study references earlier conditioning experiments that utilized Streptavidin-ZAP (IT-27) in combination with biotinylated CD45 antibodies to selectively deplete hematopoietic stem cells in murine HSCT models, typically administered as a single intravenous dose of approximately 75 µg per mouse.
