Les auteurs tiennent à remercier John Marston pour l&#39;expert de l&#39;élevage et le Dr Marco A. Passini de l&#39;assistance technique dans les premiers stades de ce projet. Ce travail a été financé par la subvention de la National Institutes of Health à CLL (R01NS41584; R01HD054413).

1. Injection intracérébroventriculaire <ol><li> La première étape est la préparation des solutions mères d&#39;injection; ces solutions sont un vecteur viral, l&#39;ADN plasmidique, la drogue, et doit être injecté dans des conditions stériles. </li><li> Mélangez un titre désiré de vecteurs viraux (5-7 au total ul) avec 0,05% p / v bleu trypan dans du PBS pour la visualisation du site d&#39;injection. </li><li> Solution de l&#39;ADN plasmidique (5 au total l uL) contient du D-(+)-glucose à 20% (p / v) (1 pl), le bleu trypan (0,05%) PBS (1 pl), un plasmide (~ 5 ~ g / ~ L ) (2 ~ L), et 2,5 kDa linéaires PEI homopolymère (150 mm) (1 ~ L). </li><li> Immobiliser le PND 2 nouveau-nés par l&#39;intermédiaire cryo-anesthésie pendant 1-2 minutes. </li><li> L&#39;aiguille utilisée pour cette injection est un micro-litre micropipette calibrée en verre stérilisé qui est attachée à une seringue de 3 ml 3 ml de Hamilton grâce à un long tube. </li><li> Pause de la pointe de l&#39;aiguille (avec une spatule) pour ajuster la pénétration de 2 mm dans le crâne. Placez l&#39;aiguille en diagonale dans le microtube contenant la solution injectable. Chargez la solution injectable dans l&#39;aiguille en tirant délicatement sur le piston de la seringue. </li><li> Après l&#39;absorption de la solution, dissocier la seringue dans le tube, puis tirer le piston plus loin et puis l&#39;attacher à l&#39;aiguille de nouveau. </li><li> Tenez l&#39;aiguille dans la main droite entre le pouce et l&#39;index et le lieu de la seringue entre le majeur et l&#39;annulaire avec le plongeur de toucher la paume de la main droite. </li><li> Saisir la souris immobilisé fermement par la peau derrière la tête avec la main gauche et placer sur une lumière à fibre optique pour éclairer les structures anatomiques pertinents qui peuvent être utilisées comme guide. </li><li> Insérez l&#39;aiguille de 2 mm de profondeur, perpendiculairement à la surface du crâne, à un emplacement d&#39;environ 0,25 mm latéralement à la suture sagittale et 0.50 à 0.75 mm rostrale à la suture néonatale coronaire (figure 1A). Ensuite, poussez le piston à l&#39;aide de la paume de la la main droite très lentement et prudemment. Moniteur pour les bateaux de rupture ou une enflure du visage. </li><li> Retirez les aiguille 15 secondes après l&#39;arrêt du mouvement du piston pour empêcher le retour. </li><li> Pour récupérer, garder la souris pendant 5-10 minutes dans un récipient chauffé jusqu&#39;à ce mouvement et la réactivité générale est restaurée. </li></ol> 2. L&#39;injection intraveineuse via la veine temporale / du visage <ol><li> La solution à injecter doit être préparée et complétée par des colorants alimentaires, filtrée vert à dilution 1:100 et injecté dans des conditions stériles. </li><li> Joindre un petit plastique Luer à l&#39;extrémité d&#39;une seringue en verre 100 uL de Hamilton. Pour l&#39;Luer, joignez une jauge de 33 pouces 0,25 aiguille hypodermique. S&#39;assurer que toutes les pièces sont correctement connectés. </li><li> Charger la seringue avec le volume à injecter, assurant qu&#39;il n&#39;y a pas d&#39;air dans la seringue d&#39;injection d&#39;air dans le récipient est létale. Il est souvent utile de pipette le volume à injecter jusqu&#39;à un morceau de parafilm. Cela permet la visualisation claire de l&#39;absorption de la solution dans la seringue. </li><li> Un Transilluminateur Sight Wee est utilisée pour visualiser facilement la veine temporale superficielle, ou veine faciale, dans le nouveau-né (figure 2A). Avant l&#39;injection, sécuriser le nouveau-né à l&#39;aide de ruban transilluminateur chirurgicale. Gaze doit être placé entre le nouveau-né et le ruban adhésif pour éviter d&#39;endommager le ruban de la peau de l&#39;animal. Fixez l&#39;animal à l&#39;transilluminateur de son côté, veillant à ce que la bande ne pas empêcher la respiration. Le cou du nouveau-né doit être doucement tournées de telle sorte que la veine faciale est facilement visible et le nez doivent être scellés pour stabiliser la tête. </li><li> En utilisant une loupe bandeau 2.25x pour permettre une visualisation plus facile, lentement insérer l&#39;aiguille dans la veine. La veine est très superficielle si l&#39;aiguille doit rester visible sous la peau. </li><li> Lentement infuser le volume de la solution dans la veine. Le colorant vert permet une visualisation facile de l&#39;injection. </li><li> Attendez 15 secondes avant de retirer l&#39;aiguille car il ya un décalage entre totalement enfoncer le piston de la seringue et l&#39;expulsion de la solution restante due à l&#39;alésage aiguille extrêmement étroites. </li><li> Après avoir retiré l&#39;aiguille, l&#39;utilisation de gaze pour appliquer une pression au site d&#39;injection jusqu&#39;à ce que le saignement cesse. </li><li> Surveiller le nouveau-né pour des signes de détresse. Après une injection correcte, pas de détresse manifeste doit être observé. Le nouveau-né doit être donné à environ 5 minutes pour récupérer avant qu&#39;il ne soit retourné à la cage. </li><li> Rincer l&#39;unité d&#39;aiguille / seringue avec du PBS dans entre les injections de sang dans l&#39;aiguille rapidement obstruer due à petit alésage. </li></ol> 3. Les résultats représentatifs: ICV injection: Le cerveau peut être récoltée à des moments différents post-injection et visualisées à démontrer la technique d&#39;injection réussie. Si le colorant n&#39;est pas ajouté à la solution injectable, il sera difficile de vérifier l&#39;exactitude de l&#39;enprojection. Injection appropriée d&#39;un des ventricules permettra la distribution du bleu trypan sur le côté injecté du cerveau environ 10-15 minutes après l&#39;injection (figure 1B). Une distribution uniforme de bleu trypan dans les deux hémisphères droit et gauche cérébrale et bulbes olfactifs seront visibles environ 60 minutes après l&#39;injection (figure 1C). Cela est dû à la connectivité des ventricules cérébraux qui va permettre la diffusion du colorant bleu pour le ventricule adjacent. Injections précises peuvent également être visualisés par la dispersion du colorant bleu dans le canal rachidien rostral centrale d&#39;environ un délai de 12 heures après l&#39;injection (figure 1D). Injections inexactes peuvent être distingués par le manque de couleur bleue dans les hémisphères cérébraux. Dans ce cas, la profondeur de l&#39;aiguille n&#39;était pas suffisante et la solution injectable a probablement distribués sous la peau. Une autre possibilité est que l&#39;aiguille pénètre trop profondément dans le cerveau, ce qui passe au-delà du ventricule et la solution est vidé sous les ventricules cérébraux. Injection IV: Précis et efficace injection dans la veine temporale / du visage peuvent être visualisées immédiatement après l&#39;injection. Comme la solution est injectée, le colorant vert permet la visualisation de la solution de saisie et qui coule à travers la veine faciale (figure 2A). De plus, la couleur de peau altérée de la souris seront observées après l&#39;injection. Normales du nouveau-né de couleur rose est converti en vert, en raison de la présence de colorant alimentaire vert dans la solution injectable (figure 2B). La mesure du changement de couleur verte observée dans le nouveau-né dépend de la concentration de colorant utilisé. Pour la visualisation simple de l&#39;injection et pendant une période de pratique, une dilution de 1:50 est recommandée. Cependant, la tonicité de la peau considérablement modifié se traduit souvent par le chiot d&#39;être rejeté par la mère et donc, la suppression de la teinture ou une concentration significativement réduit doit être considérée lors des procédures expérimentales. Une injection inexact entraînera l&#39;accumulation de colorant vert sous la peau au site d&#39;injection. D&#39;injection incomplète, ce qui se produit lorsque l&#39;ouverture de l&#39;aiguille n&#39;est pas complètement insérée dans la veine, est vu quand une solution flux dans la veine et quelques s&#39;accumule sous la peau. Si ce n&#39;est observée, l&#39;aiguille doit être introduite plus loin dans le navire. <img src="/files/ftp_upload/2968/2968fig1.jpg" alt="Figure 1"/> Figure 1. Démonstration d&#39;injections ICV réussi à PDN2 souris. Un Schéma) des sites d&#39;injection utilisés dans les injections ICV dans les ventricules. B) du cerveau de l&#39;ICV injecté Pup au bleu trypan dans du PBS sur le ventricule gauche, photo prise 15 minutes après l&#39;injection. C ) du cerveau de l&#39;ICV injecté Pup au bleu trypan dans du PBS sur le ventricule gauche, photo prise 60 minutes après l&#39;injection. D) Rostral centrale du canal rachidien est montré dans ICV injecté chiot avec du bleu trypan dans du PBS sur le ventricule gauche, photo prise 12 heures après l&#39;injection. <img src="/files/ftp_upload/2968/2968fig2.jpg" alt="Figure 2"/> Figure 2. Démonstration d&#39;injections IV réussi à PDN2 souris. Un Schéma) de veine faciale utilisés pour injections IV. B) Pup IV injectés avec un colorant vert dans PBS par rapport aux non-injecté congénères, Photo prise injection immédiatement après.

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Aucun conflit d&#39;intérêt déclaré.

Les recherches utilisant des modèles murins de la maladie nécessite souvent l&#39;administration de drogues ou autres substances aux nouveau-nés. Dans cette vidéo, nous démontrons l&#39;étape par étape des procédures impliquant deux types de stratégies d&#39;injection qui peut être utilisé pour cibler le système nerveux central: 1) l&#39;injection directe dans le SNC en utilisant intracérébroventriculaire (ICV) d&#39;injection, ou 2) par injection IV ciblant temporel / veine faciale. Le calendrier de ces i...

<table border="1"><tbody><tr><th> Nom du réactif </th><th> Société </th><th> Numéro de catalogue </th><th> Commentaires (optionnel) </th></tr><tr><td> Colorant alimentaire vert </td><td> McCormick </td><td> n / a </td><td> Doit être filtrée </td></tr><tr><td> Hamilton verre seringue (100 pi) </td><td> Sigma Aldrick </td><td> 20702 </td><td></td></tr><tr><td> Discussion LuerMxF White Style Nylon </td><td> Petites pièces, Inc </td><td> VPLF-LC78-1-25 </td><td></td></tr><tr><td> Beaux aiguilles hypodermiques de calibre </td><td> Popper </td><td> 7111 </td><td> Taille: 33 (GTS) x ¼ &quot;(6,35 mm) </td></tr><tr><td> Transilluminateur Sight Wee </td><td> Respironics </td><td> 1017920 </td><td></td></tr><tr><td> 2.25x Bandeau Loupe </td><td> MagEyes </td><td> Modèle n ° 5 </td><td> Sélectionnez un grossissement d&#39;ajustement des préférences individuelles </td></tr></tbody></table>

delivery of therapeutic agents through intracerebroventricular (icv) and intravenous (iv) injection in mice

Malgré le rôle protecteur que barrière hémato-encéphalique joue dans le blindage du cerveau, il limite l&#39;accès au système nerveux central (SNC) qui résulte le plus souvent par un échec des thérapeutiques potentiels conçu pour 1,2 des troubles neurodégénératifs. Les maladies neurodégénératives comme l&#39;atrophie musculaire spinale (SMA), dans lequel les neurones moteurs inférieurs sont touchés, peuvent grandement bénéficier de l&#39;introduction des agents thérapeutiques dans le SNC. Le but de cette vidéo est de démontrer deux paradigmes d&#39;injection différents pour livrer le matériel thérapeutiques dans des souris néonatales tôt après la naissance. Une de ces méthodes consiste à injecter directement dans cérébrale ventricules latéraux (intracérébroventriculaire) qui se traduit par la livraison des matériaux dans le SNC à travers le liquide céphalo-rachidien 3,4. La deuxième méthode est une injection dans la veine temporale (intraveineuse) qui peuvent introduire des produits thérapeutiques différentes dans le système circulatoire, conduisant à une administration systémique, y compris les 5 SNC. Transduction généralisée du SNC est réalisable si un vecteur approprié virale et le sérotype viral est utilisé. Visualisation et utilisation de la veine temporale pour injection est faisable à jour postnatal 6. Toutefois, si le matériel livré est destiné à atteindre le SNC, ces injections devraient avoir lieu pendant que la barrière hémato-encéphalique est plus perméable à cause de son statut immatures, de préférence avant le jour après la naissance 2. La barrière hémato pleinement développé du cerveau limite grandement l&#39;efficacité de l&#39;administration par voie intraveineuse. Les deux systèmes de livraison sont simples et efficaces une fois que les aptitudes chirurgicale est réalisée. Ils ne nécessitent pas de dispositifs de grande chirurgie et peut être réalisée par une seule personne. Toutefois, ces techniques ne sont pas sans défis. La petite taille du postnatale jour 2 chiots et les domaines ultérieurs petite cible peut faire les injections difficiles à réaliser et d&#39;abord difficile à reproduire.

Watch this Scientific Journal Video about Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice at JoVE.com

Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice

Cet article illustre deux méthodes très différentes d&#39;injection: 1) dans le cerveau (intracérébroventriculaire) et 2) systémique (intraveineuse) d&#39;introduire des agents thérapeutiques dans le système nerveux central de souris néonatales.

Délivrance d&#39;agents thérapeutiques à travers intracérébroventriculaire (ICV) et intraveineuse (IV) par injection chez la souris

Despite the protective role that blood brain barrier plays in shielding the brain, it limits the access to the central nervous system (CNS) which most ...

delivery-therapeutic-agents-through-intracerebroventricular-icv

Research

JoVE Journal

Medicine

Delivery of Therapeutic Agents Through Intracerebroventricular (ICV) and Intravenous (IV) Injection in Mice

58.7K vues.  University of Missouri. Cet article illustre deux méthodes très différentes d'injection: 1) dans le cerveau (intracérébroventriculaire) et 2) systémique (intraveineuse) d'introduire des agents thérapeutiques dans le système nerveux central de souris néonatales.

Vidéo: Delivery of Therapeutic Agents Through Intracerebroventricular ICV and Intravenous IV Injection in Mice

Orthotopic Xenografting of Human Luciferase-Tagged Malignant Peripheral Nerve Sheath Tumor Cells for in vivo Testing of Candidate Therapeutic Agents

Although in vitro screens are essential for the initial identification of candidate therapeutic agents, a rigorous assessment of the drug's ability to inhibit tumor growth must be performed in a suitable animal model. The type of animal model that is best for this purpose is a topic of intense discussion. Some evidence indicates that preclinical trials examining drug effects on tumors arising in transgenic mice are more predictive of clinical outcome1and so candidate therapeutic agents are often tested in these models. Unfortunately, transgenic models are not available for many tumor types. Further, transgenic models often have other limitations such as concerns as to how well the mouse tumor models its human counterpart, incomplete penetrance of the tumor phenotype and an inability to predict when tumors will develop.
Consequently, many investigators use xenograft models (human tumor cells grafted into immunodeficient mice) for preclinical trials if appropriate transgenic tumor models are not available. Even if transgenic models are available, they are often partnered with xenograft models as the latter facilitate rapid determination of therapeutic ranges. Further, this partnership allows a comparison of the effectiveness of the agent in transgenic tumors and genuine human tumor cells. Historically, xenografting has often been performed by injecting tumor cells subcutaneously (ectopic xenografts). This technique is rapid and reproducible, relatively inexpensive and allows continuous quantitation of tumor growth during the therapeutic period2. However, the subcutaneous space is not the normal microenvironment for most neoplasms and so results obtained with ectopic xenografting can be misleading due to factors such as an absence of organ-specific expression of host tissue and tumor genes. It has thus been strongly recommended that ectopic grafting studies be replaced or complemented by studies in which human tumor cells are grafted into their tissue of origin (orthotopic xenografting)2. Unfortunately, implementation of this recommendation is often thwarted by the fact that orthotopic xenografting methodologies have not yet been developed for many tumor types.
Malignant peripheral nerve sheath tumors (MPNSTs) are highly aggressive sarcomas that occur sporadically or in association with neurofibromatosis type 13and most commonly arise in the sciatic nerve4. Here we describe a technically straightforward method in which firefly luciferase-tagged human MPNST cells are orthopically xenografted into the sciatic nerve of immunodeficient mice. Our approach to assessing the success of the grafting procedure in individual animals and subsequent non-biased randomization into study groups is also discussed.

Orthotopic Xenografting of Human Luciferase-Tagged Malignant Peripheral Nerve Sheath Tumor Cells for in vivo Testing of Candidate Therapeutic Agents

A method for reliably grafting luciferase-tagged human malignant peripheral nerve sheath tumor cells into the sciatic nerve of immunodeficient mice is described. The use of bioluminescence imaging to demonstrate proper establishment of tumor grafts and criteria for random segregation of animals into study groups are also discussed.

Orthotopique xénogreffe de l&#39;homme-luciférase Tagged malin cellules nerveuses périphériques tumeur Gaine pour In vivo Test d&#39;agents thérapeutiques candidats

Although in vitro screens are essential for the initial identification of candidate therapeutic agents, a rigorous assessment of the drug's ability to ...

Recherche

Médecine

Slow-release Drug Delivery through Elvax 40W to the Rat Retina: Implications for the Treatment of Chronic Conditions

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these diseases. Chronic retinal diseases such as retinal oedema or neovascularization usually require multiple intraocular injections to effectively treat the condition. However, the risks associated with these injections increase with repeated delivery of the drug. Therefore, alternative delivery methods need to be established in order to minimize the risks of reinjection. Several other investigations have developed methods to deliver drugs over extended time, through materials capable of releasing chemicals slowly into the eye. In this investigation, we outline the use of Elvax 40W, a copolymer resin, to act as a vehicle for drug delivery to the adult rat retina. The resin is made and loaded with the drug. The drug-resin complex is then implanted into the vitreous cavity, where it will slowly release the drug over time. This method was tested using 2-amino-4-phosphonobutyrate (APB), a glutamate analogue that blocks the light response of the retina. It was demonstrated that the APB was slowly released from the resin, and was able to block the retinal response by 7 days after implantation. This indicates that slow-release drug delivery using this copolymer resin is effective for treating the retina, and could be used therapeutically with further testing.

This paper details how Elvax 40W can be used as a slow-release method for drug delivery to the adult rat retina. The protocol for preparing, loading, and delivering the drug-resin complex to the eye is described.

À libération lente Drug Delivery par Elvax 40W pour le Retina Rat: Implications pour le traitement des maladies chroniques

Diseases of the retina are difficult to treat as the retina lies deep within the eye. Invasive methods of drug delivery are often needed to treat these ...

Ultrasound-guided Transthoracic Intramyocardial Injection in Mice

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. Experiments involving myocardial injection are currently performed by direct surgical access through a thoracotomy. While convenient when performed at the time of another experimental manipulation such as coronary artery ligation, the need for an invasive procedure for intramyocardial delivery limits potential experimental designs. With ever improving ultrasound resolution and advanced noninvasive imaging modalities, it is now feasible to routinely perform ultrasound-guided, percutaneous intramyocardial injection. This modality efficiently and reliably delivers agents to a targeted region of myocardium. Advantages of this technique include the avoidance of surgical morbidity, the facility to target regions of myocardium selectively under ultrasound guidance, and the opportunity to deliver injectate to the myocardium at multiple, predetermined time intervals. With practiced technique, complications from intramyocardial injection are rare, and mice quickly return to normal activity on recovery from anesthetic. Following the steps outlined in this protocol, the operator with basic echocardiography experience can quickly become competent in this versatile, minimally invasive technique.

Echocardiography-guided percutaneous intramyocardial injection represents an efficient, reliable, and targetable modality for the delivery of gene transfer agents or cells into the murine heart. Following the steps outlined in this protocol, the operator can quickly become competent in this versatile, minimally invasive technique.

Guidée par échographie transthoracique intramyocardique injection chez la souris

Murine models of cardiovascular disease are important for investigating pathophysiological mechanisms and exploring potential regenerative therapies. ...

Testing the Efficacy of Pharmacological Agents in a Pericardial Target Delivery Model in the Swine

To date, many pharmacological agents used to treat or prevent arrhythmias in open-heart cases create undesired systemic side effects. For example, antiarrhythmic drugs administered intravenously can produce drops in systemic pressure in the already compromised cardiac patient. While performing open-heart procedures, surgeons will often either create a small port or form a pericardial cradle to create suitable fields for operation. This access yields opportunities for target pharmacological delivery (antiarrhythmic or ischemic preconditioning agents) directly to the myocardial tissue without undesired side effects.
We have developed a swine model for testing pharmacological agents for target delivery within the pericardial fluid. While fully anesthetized, each animal was instrumented with a Swan-Ganz catheter as well as left and right ventricle pressure catheters, and pacing leads were placed in the right atrial appendage and the right ventricle. A medial sternotomy was then performed and a pericardial access cradle was created; a plunge pacing lead was placed in the left atrial appendage and a bipolar pacing lead was placed in the left ventricle. Utilizing a programmer and a cardiac mapping system, the refractory period of the atrioventricular node (AVN), atria and ventricles was determined. In addition, atrial fibrillation (AF) induction was produced utilizing a Grass stimulator and time in AF was observed. These measurements were performed prior to treatment, as well as 30 min&#160;and 60 min&#160;after pericardial treatment. Additional time points were added for selected studies. The heart was then cardiopleged and reanimated in a four chamber working mode. Pressure measurements and function were recorded for 1 hr after reanimation. This treatment strategy model allowed us to observe the effects of pharmacological agents that may decrease the incidence of cardiac arrhythmias and/or ischemic damage, during and after open-heart surgery.

We have developed a swine model for the target delivery of pharmacological agents within the pericardial space/fluid. Using this approach, the relative benefits of administered agents on induced atrial fibrillation, relative refractory periods and/or ischemic protection can be investigated.

Test de l&#39;efficacité des agents pharmacologiques dans un modèle de prestation péricardique cible dans la Swine

To date, many pharmacological agents used to treat or prevent arrhythmias in open-heart cases create undesired systemic side effects. For example, ...

Disposable Dosators for Pulmonary Insufflation of Therapeutic Agents to Small Animals

Development of new therapeutic products requires efficacy testing in an animal model. The pulmonary route of administration can be utilized to deliver drugs locally and systemically. Evaluation of dry powder aerosols necessitates an efficient dispersion mechanism to maintain high concentrations in an exposure chamber or for direct endotracheal administration. While solutions exist to expose animals by passive inhalation to dry powder aerosols, most require masses of powder in large excess of the dose delivered. This precludes conducting early feasibility studies as insufficient drug is available at the research or early development stage to support the dose delivery requirements for conventional aerosol delivery systems. When designing an aerosol drug product, aerodynamic performance can relate directly to delivery efficiency and efficacy. Dispersion of powder into an aerosol requires energy input sufficient to overcome interparticulate forces, and particle engineering approaches can substantially improve aerosol performance. We have developed a dispersion system (dosator) which can aerosolize engineered dry powder aerosols efficiently for the purpose of direct pulmonary insufflation, dispersion into an exposure system or generation for analytical purposes.

During development of drugs for pulmonary delivery, it is necessary to evaluate pharmacokinetics and efficacy in an animal model. We present a method to build a disposable aerosol dispersion system from of-the-shelf components that can be used to administer intrapulmonary dry powder aerosol to rodents.

Doseurs à usage unique pour pulmonaire Insufflation d&#39;agents thérapeutiques pour les petits animaux

Development of new therapeutic products requires efficacy testing in an animal model. The pulmonary route of administration can be utilized to deliver ...

Intranasal Delivery of Therapeutic Stem Cells to Glioblastoma in a Mouse Model

The intrinsic tropism towards brain malignancies renders stem cells as promising carriers of therapeutic agents against malignant tumors. The delivery of therapeutic stem cells via the intranasal route is a recently discovered alternative strategy, with strong potential for clinical translation, due to its non-invasive nature compared to intracranial implantation or delivery via systemic routes. The lack of blood brain barrier further strengthens the therapeutic potential of stem cells undergoing intranasal brain entry. This article summarizes the essential techniques utilized in our studies and outlines the basic principles of intranasal strategy for stem cell delivery using a mouse model of intracranial glioma xenografts. We demonstrate the optimized procedures that generate consistent and reproducible results with specific predetermined experimental parameters and offer guidelines for streamlined work flow that ensure efficient execution and reliable experimental outcome. The article is designed to serve as a baseline for further experimental customization based on hypothesis, stem cell types, or tumor specifics.

Stem cells are promising therapeutic carriers to treat brain tumors due to their intrinsic tumor tropism. Non-invasive intranasal stem cell delivery bypasses the blood brain barrier and demonstrates strong potential for clinical translation. This article summarizes the basic principles of intranasal stem cell delivery in a mouse model of glioma.

Livraison intradermique de cellules souches thérapeutiques au glioblastome dans un modèle de souris

The intrinsic tropism towards brain malignancies renders stem cells as promising carriers of therapeutic agents against malignant tumors. The delivery of ...

A Rat Carotid Artery Pressure-Controlled Segmental Balloon Injury with Periadventitial Therapeutic Application

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the luminal surface area in arteries thereby reducing adequate blood flow to organs and distal tissues. Clinically, revascularization procedures such as balloon angioplasty with or without stent placement aim to restore blood flow. Although these procedures reestablish blood flow by reducing plaque burden, they damage the vessel wall, which initiates the arterial healing response. The prolonged healing response causes arterial restenosis, or re-narrowing, ultimately limiting the long-term success of these revascularization procedures. Therefore, preclinical animal models are integral for analyzing the pathophysiological mechanisms driving restenosis, and provide the opportunity to test novel therapeutic strategies. Murine models are cheaper and easier to operate on than large animal models. Balloon or wire injury are the two commonly accepted injury modalities used in murine models. Balloon injury models in particular mimic the clinical angioplasty procedure and cause adequate damage to the artery for the development of restenosis. Herein we describe the surgical details for performing and histologically analyzing the modified, pressure-controlled rat carotid artery balloon injury model. Additionally, this protocol highlights how local periadventitial application of therapeutics can be used to inhibit neointimal hyperplasia. Lastly, we present light sheet fluorescence microscopy as a novel approach for imaging and visualizing the arterial injury in three-dimensions.

The rat carotid artery balloon injury mimics the clinical angioplasty procedure performed to restore blood flow in atherosclerotic vessels. This model induces the arterial injury response by distending the arterial wall, and denuding the intimal layer of endothelial cells, ultimately causing remodeling and an intimal hyperplastic response.

Une blessure de ballon segmental contrôlé par pression d’artère de rat carotide avec l’application thérapeutique periadventitial

Cardiovascular disease remains the leading cause of death and disability worldwide, in part due to atherosclerosis. Atherosclerotic plaque narrows the ...

Intratracheal Administration of Dry Powder Formulation in Mice

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper introduces a noninvasive method of intratracheal delivery of dry powder formulation in mice. A dry powder loading device that consists of a 200 &#181;L gel loading pipette tip connected to an 1 mL syringe via a three-way stopcock is presented. A small amount of dry powder (1-2 mg) is loaded into the pipette tip and dispersed by 0.6 mL of air in the syringe. Because pipette tips are disposable and inexpensive, different dry powder formulations can be loaded into different tips in advance. Various formulations can be evaluated in the same animal experiment without device cleaning and dose refilling, thereby saving time and eliminating the risk of cross-contamination from residual powder. The extent of powder dispersion can be inspected by the amount of powder remaining in the pipette tip. A protocol of intubation in mouse with a custom-made light source and a guiding cannula is included. Proper intubation is one of the key factors that influences the intratracheal delivery of dry powder formulation to the deep lung region of the mouse.

Dry powder formulations for inhalation have great potential in treating respiratory diseases. Before entering human studies, it is necessary to evaluate the efficacy of the dry powder formulation in preclinical studies. A simple and noninvasive method of the administration of dry powder in mice through the intratracheal route is presented.

Administration intratrachéale de formulation de poudre sèche chez la souris

In the development of inhalable dry powder formulations, it is essential to evaluate their biological activities in preclinical animal models. This paper ...

Décoction de Liujunzi : un traitement efficace pour la prévention de l’UC-CRC

Establishment of Coloproctitis Cancer Model in Mice and Evaluation of Therapeutic Effect of Chinese Medicine

Colorectal cancer (CRC) is a common malignancy of the digestive system and has become the third most common malignancy worldwide and the second leading cause of malignancy-related death. Ulcerative coloproctitis (UC) is a precancerous lesion, and UC-associated CRC (UC-CRC) is the most common subtype of CRC. Therefore, a reasonable UC-CRC model is the cornerstone and guarantee of new drug development. Traditional Chinese medicine (TCM) has been widely used in the treatment of UC-CRC due to its good efficacy. As a classic tonic prescription of TCM, Liujunzi decoction (LJZD) has been widely used in the treatment of UC-CRC. In this study, a UC-CRC model was established by combining azomethane and dextran sulfate sodium, and the LJZD was administered. The data confirmed that LJZD can effectively inhibit cancer transition in UC-CRC by using mouse body weight, colorectal length, pathological and inflammatory factors, colorectal barrier function, and cancer markers. This protocol provides a system for evaluating the efficacy of TCM in the prevention and treatment of UC-CRC.

Pleins feux sur l’auteur : La décoction de liujunzi comme traitement traditionnel chinois du cancer de la coloproctite

This protocol provides a mouse model of ulcerative coloproctitis-associated colorectal cancer induced by azomethane combined with dextran sulfate sodium. The model was used to evaluate the efficacy of traditional Chinese medicine compounds in the prevention and treatment of colorectal cancer.

Établissement d’un modèle de cancer de la coloproctite chez la souris et évaluation de l’effet thérapeutique de la médecine chinoise

Colorectal cancer (CRC) is a common malignancy of the digestive system and has become the third most common malignancy worldwide and the second leading ...