scholarly journals 3013 Combined Annulus Fibrosus and Nucleus Pulposus Repair Prevents Degeneration in the Ovine Lumbar Spine

2019 ◽  
Vol 3 (s1) ◽  
pp. 6-6
Author(s):  
Stephen Sloan ◽  
Christoph Wipplinger ◽  
Sirtac Kirnaz ◽  
Rodrigo Navarro-Ramirez ◽  
Antonella Schivinato ◽  
...  
Keyword(s):  
Lumbar Spine ◽  
Combined Treatment ◽  
Quantitative Mri ◽  
Disc Height ◽  
Degenerative Changes ◽  
Large Animal Model ◽  
Large Animal ◽  
The Individual ◽  
Pfirrmann Grade

OBJECTIVES/SPECIFIC AIMS: The objective of this study is to assess the efficacy of combined AF and NP repairs to prevent degenerative changes and restore native disc morphology in an in vivo large animal model. We hypothesize that combined repairs will prevent disc degeneration following injury to a greater extent than the individual repairs after 6 weeks in vivo, as demonstrated through disc height measurements and disc morphology. METHODS/STUDY POPULATION: A total of 8 skeletally mature female Finn sheep were used in this study. Following a previously described method, IVDs from L1 to L6 of the lumbar spine were exposed using a lateral access, extraperitoneal approach5. IVDs were randomized into 5 treatment groups: 1) intact discs, 2) discs injured via a 3 cm x 1 cm box annulotomy and partial nucleotomy, 3) injury followed by a high density collagen (HDC) AF patch, 4) injury followed by injection of a modified hyaluronic acid (HA) into the NP, and 5) injury followed by both the HDC AF patch and HA NP injection. The HDC treatment was 15 mg/mL type-I collagen mixed with 0.06mM riboflavin, injected at the defect site and crosslinked in situ with blue light. The NP injection was HA modified with C16 side chains to increase the viscosity of the hydrogel (HYADD 4®)6. At 6 weeks post-operatively, sheep were sacrificed and had 3T magnetic resonance images (MRI) taken of their lumbar spine. Disc height analysis and Pfirrmann grading were performed on each segment using MR images. Additionally, quantitative MRI analyses were performed using a custom MATLAB algorithm that segments NP from the surrounding tissue and directly measures the NP volume. ANOVA with Tukey’s HSD was used to determine statistical significance between groups for disc height and quantitative MRI analyses, and the Kruskal-Wallis test with Mann-Whitney tests was used to statistically analyze Pfirrmann Grades. All animal use followed approved IACUC protocol. RESULTS/ANTICIPATED RESULTS: As shown in axial MR images (Figure 1A), intact discs had hyperintense NP with a distinct border to the AF. The discs receiving injury with no treatment had hypointense NP with no distinct border between the AF and NP. Individual and combined treatment with the HA NP injection and HDC AF patch appeared to preserve the hyperintense NP signal and AF/NP border. Intact control discs were not degenerated and had an average Pfirrmann grade of 1 (Figure 1B), while injured, untreated discs had significant degeneration with an average Pfirrmann grade of 3. Discs receiving the HA NP injection and collagen AF patch individually showed fewer signs of degeneration than the injured alone, and the combined treatment resulted in the least amount of degeneration with Pfirrmann grades not significantly different than the intact controls. Disc height index confirmed the trends seen in the Pfirrmann grades (Figure 1C), where injured discs lost 20% of the intact disc height, the individual NP and AF repairs restored 5-10% of intact disc height, and the combined repairs preserved 90% of the intact disc height. The NP voxel count of all treatment groups were similar to the intact controls (Figure 1D). DISCUSSION/SIGNIFICANCE OF IMPACT: The objective of this study was to determine how combined AF and NP can prevent degenerative changes to the disc in a large animal in vivo model. Pfirrmann grading and disc height index results show that the greatest preservation of disc morphology was seen with combined AF and NP repairs, while the individual strategies prevented degenerative changes better than injury with no treatment. It appears the HA NP injection restores lost water content to the disc following injury, and the AF collagen patch plays a role in maintaining the NP repair within the disc. This is the first study to our knowledge to attempt combined AF and NP repairs in an in vivo large animal model. Combining NP and AF repairs leads to significantly improved outcomes following disc injury, which warrants the translation of combined repairs into the clinic to improve patient outcomes with degenerative disc disease involving NP and AF.

scholarly journals Combined Nucleus Pulposus Augmentation and Annulus Fibrosus Repair Prevents Intervertebral Disc Degeneration After Discectomy

Neurosurgery ◽  
2019 ◽  
Vol 66 (Supplement_1) ◽  
Author(s):  
Sertac Kirnaz ◽  
Stephen Sloan ◽  
Christoph Wipplinger ◽  
Franziska Anna Schmidt ◽  
Roger Hartl ◽  
...  
Keyword(s):  
Nucleus Pulposus ◽  
Disc Degeneration ◽  
Annulus Fibrosus ◽  
Combined Treatment ◽  
Disc Height ◽  
Histological Evaluation ◽  
Sheep Model ◽  
Mri Scans ◽  
The Individual

Abstract INTRODUCTION The objective of the current study is to assess the efficacy of combined annulus fibrosus (AF) using a high-density collagen (HDC) gel and nucleus pulposus (NP) repair using a hyaluronic acid (HA) gel in an in Vivo sheep model. METHODS We performed an anterolateral, retroperitoneal prepsoas approach to access the IVDs L1-6 in a total of 8 skeletally mature Finn sheep. IVDs were randomized into 5 groups: (1) intact, (2) injured via 3 × 10 mm box annulotomy and removal of 200 mg of NP, (3) injury and HDC gel patch for AF repair, (4) injury and injection of a HA gel into the NP, and (5) injury and HDC AF repair and NP HA replacement. At 6 wk postoperatively, sheep were sacrificed and underwent postmortem 3T-MRI scans as well as gross anatomical and histological evaluation. Disc height index (DHI) analysis and Pfirrmann grading (PG) were performed on each segment using MR images. RESULTS Intact control discs were not degenerated and had an average PG of 1 while injured, and untreated discs had a significant degeneration with an average PG of 3. Discs receiving the combined injection and collagen AF patch individually showed fewer signs of degeneration than injured alone, and the combined treatment resulted in the least amount of degeneration with PG not significantly different from the intact controls. DHI confirmed the trends seen in the PG, where injured discs lost 20% of the intact disc height, the individual NP and AF repairs restored 5% to 10% of intact disc height, and the combined repairs preserved 90% of the intact disc height. CONCLUSION PG and DHI results demonstrate that individual NP and AF repairs are able to prevent disc degeneration better than no treatment at all; however, the greatest preservation of disc health was seen with combined AF and NP repairs.

scholarly journals A patient-like swine model of gastrointestinal fibrotic strictures for advancing therapeutics

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ling Li ◽  
Mohamad I. Itani ◽  
Kevan J. Salimian ◽  
Yue Li ◽  
Olaya Brewer Gutierrez ◽  
...  
Keyword(s):  
Argon Plasma Coagulation ◽  
Argon Plasma ◽  
Large Animal Model ◽  
Swine Model ◽  
Large Animal ◽  
High Grade ◽  
Gi Tract ◽  
Endoscopic Techniques ◽  
Approved Drugs

AbstractGastrointestinal (GI) strictures are difficult to treat in a variety of disease processes. Currently, there are no Food and Drug Administration (FDA) approved drugs for fibrosis in the GI tract. One of the limitations to developing anti-fibrotic drugs has been the lack of a reproducible, relatively inexpensive, large animal model of fibrosis-driven luminal stricture. This study aimed to evaluate the feasibility of creating a model of luminal GI tract strictures. Argon plasma coagulation (APC) was applied circumferentially in porcine esophagi in vivo. Follow-up endoscopy (EGD) was performed at day 14 after the APC procedure. We noted high grade, benign esophageal strictures (n = 8). All 8 strictures resembled luminal GI fibrotic strictures in humans. These strictures were characterized, and then successfully dilated. A repeat EGD was performed at day 28 after the APC procedure and found evidence of recurrent, high grade, fibrotic, strictures at all 8 locations in all pigs. Pigs were sacrificed and gross and histologic analyses performed. Histologic examination showed extensive fibrosis, with significant collagen deposition in the lamina propria and submucosa, as well as extensive inflammatory infiltrates within the strictures. In conclusion, we report a porcine model of luminal GI fibrotic stricture that has the potential to assist with developing novel anti-fibrotic therapies as well as endoscopic techniques to address recurring fibrotic strictures in humans.

scholarly journals Niobium Carbide Loaded by Macrophage for Targeted Phototherapy Ablation of Breast Cancer

2020 ◽  
Author(s):  
Chiara Da Pieve ◽  
Gabriela Kramer Marek ◽  
Jolanta Saczko ◽  
Anant Shah ◽  
Florian Raes
Keyword(s):  
Animal Study ◽  
Human Body ◽  
Targeted Delivery ◽  
Near Infrared ◽  
Niobium Carbide ◽  
Reactive Oxygen Species Generation ◽  
Large Animal Model ◽  
Large Animal ◽  
Photodynamic Effect

ABSTRACTAltough nanomaterial-mediated phototherapy has been extensively studied, the major antitumor success is limited to treating subcutaneous tumor on nude, lacking of clinically-relevant big animal study. Therefore, it is urgent to make further investigation on the typical big model, which is more closely related to the human body. In this work, niobium carbide (NbC) was selected as photoactive substance in virtue of its outstanding near infrared (NIR) absorption properties and resultantly NIR-triggered hyperthemia and reactive oxygen species generation for the synergetic photothermal and photodynamic effect. Moreover, macrophage was used as bio-carrier for the targeted delivery of NbC and the phagocytosis of macrophages was proved to be able to retain the photothermal/photodynamic effect of NbC. Resultantly, macrophage loaded NbC could realize complete removal of solid tumor on both of nude mice and big animal of rabbits. Meanwhile, two-dimensional ultrasound, shave wave elastography (SWE) and contrast-enhanced ultrasound (CEUS) have been applied for monitoring the physiological evolutions of in vivo tumor post treatment, which clearly disclosed the photoablation process of tumor and provided a new way for the surveillance of tumor on the big animal study. Hence, large animal model study in this work presented higher clinical significance than the previous studies.SignificanceFindings show that niobium carbide carried by macrophages can be used for targeted phototherapy. At the same time, we applied the rabbit tumor model which is closer to the human body microenvironment.

scholarly journals Intracoronary Delivery of Porcine Cardiac Progenitor Cells Overexpressing IGF-1 and HGF in a Pig Model of Sub-Acute Myocardial Infarction

Cells ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2571
Author(s):  
Cristina Prat-Vidal ◽  
Verónica Crisóstomo ◽  
Isabel Moscoso ◽  
Claudia Báez-Díaz ◽  
Virginia Blanco-Blázquez ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Growth Factor ◽  
Progenitor Cells ◽  
Large Animal Model ◽  
Cardiac Progenitor Cells ◽  
Large Animal ◽  
Insulin Growth Factor ◽  
Decellularized Extracellular Matrix ◽  
Preclinical Animal Models

Human cardiac progenitor cells (hCPC) are considered a good candidate in cell therapy for ischemic heart disease, demonstrating capacity to improve functional recovery after myocardial infarction (MI), both in small and large preclinical animal models. However, improvements are required in terms of cell engraftment and efficacy. Based on previously published reports, insulin-growth factor 1 (IGF-1) and hepatocyte growth factor (HGF) have demonstrated substantial cardioprotective, repair and regeneration activities, so they are good candidates to be evaluated in large animal model of MI. We have validated porcine cardiac progenitor cells (pCPC) and lentiviral vectors to overexpress IGF-1 (co-expressing eGFP) and HGF (co-expressing mCherry). pCPC were transduced and IGF1-eGFPpos and HGF-mCherrypos populations were purified by cell sorting and further expanded. Overexpression of IGF-1 has a limited impact on pCPC expression profile, whereas results indicated that pCPC-HGF-mCherry cultures could be counter selecting high expresser cells. In addition, pCPC-IGF1-eGFP showed a higher cardiogenic response, evaluated in co-cultures with decellularized extracellular matrix, compared with native pCPC or pCPC-HGF-mCherry. In vivo intracoronary co-administration of pCPC-IGF1-eGFP and pCPC-HFG-mCherry (1:1; 40 × 106/animal), one week after the induction of an MI model in swine, revealed no significant improvement in cardiac function.

A novel in vivo large animal model of lumbar spinal joint degeneration

2018 ◽  
Vol 18 (10) ◽  
pp. 1896-1909 ◽  
Author(s):  
Tian Wang ◽  
Matthew H. Pelletier ◽  
Chris Christou ◽  
Rema Oliver ◽  
Ralph J. Mobbs ◽  
...  
Keyword(s):  
Animal Model ◽  
Large Animal Model ◽  
Large Animal ◽  
Joint Degeneration ◽  
Lumbar Spinal

scholarly journals Autologous transplantation of canine long-term marrow culture cells genetically marked by retroviral vectors

Blood ◽  
1992 ◽  
Vol 79 (2) ◽  
pp. 356-364 ◽  
Author(s):  
RF Carter ◽  
AC Abrams-Ogg ◽  
JE Dick ◽  
SA Kruth ◽  
VE Valli ◽  
...  
Keyword(s):  
Gene Transfer ◽  
Autologous Transplantation ◽  
Large Animal Model ◽  
Multiple Infections ◽  
Large Animal ◽  
Retroviral Infection ◽  
Hematopoietic Stem ◽  
Marrow Cells

Abstract Retroviral infection of bone marrow cells in long-term marrow cultures (LTMCs) offers several theoretical advantages over other methods for gene transfer into hematopoietic stem cells. To investigate the feasibility of this approach in a large animal model system, we subjected LTMCs from nine dogs to multiple infections with retrovirus containing the neomycin phosphotransferase gene (neo) during 21 days of culture. Feeder layers, cocultivation, polycations, and selection were not used. The in vitro gene transfer efficiency was 70% as determined by polymerase chain reaction amplification of neo sequences in colony- forming unit granulocyte-macrophage (CFU-GM) obtained from day-21 LTMCs. Day-21 LTMC cells were infused into autologous recipients with (four dogs) and without (three dogs) marrow-ablative conditioning. At 3 months posttransplant, up to 10% of marrow cells contained the neo gene. This percentage declined to 0.1% to 1% at 10 to 21 months posttransplant. Neo was also detected in individual CFU-GM, burst- forming unit-erythroid (BFU-E), and CFU-Mix progenitors derived from marrow up to 21 months postinfusion and in cultures of peripheral blood- derived T cells up to 19 months postinfusion. There was no difference in the percentage of neo-marked cells present when dogs that received marrow ablative conditioning were compared with dogs receiving no conditioning. Detection of neo-marked marrow cells almost 2 years after autologous transplantation in a large mammalian species shows that retroviral infection of marrow cells in LTMCs is a potentially nontoxic and efficient protocol for gene transfer. Further, our results suggest that marrow conditioning and in vivo selection pressure to retain transplanted cells may not be absolute requirements for the retention of genetically marked cells in vivo.

scholarly journals Light-degradable hydrogels as dynamic triggers for gastrointestinal applications

2020 ◽  
Vol 6 (3) ◽  
pp. eaay0065 ◽  
Author(s):  
Ritu Raman ◽  
Tiffany Hua ◽  
Declan Gwynne ◽  
Joy Collins ◽  
Siddartha Tamang ◽  
...  
Keyword(s):  
Ex Vivo ◽  
Implantable Devices ◽  
Large Animal Model ◽  
Large Animal ◽  
Gi Tract ◽  
Biomedical Device ◽  
Precise Tool ◽  
And Performance

Triggerable materials capable of being degraded by selective stimuli stand to transform our capacity to precisely control biomedical device activity and performance while reducing the need for invasive interventions. Here, we describe the development of a modular and tunable light-triggerable hydrogel system capable of interfacing with implantable devices. We apply these materials to two applications in the gastrointestinal (GI) tract: a bariatric balloon and an esophageal stent. We demonstrate biocompatibility and on-demand triggering of the material in vitro, ex vivo, and in vivo. Moreover, we characterize performance of the system in a porcine large animal model with an accompanying ingestible LED. Light-triggerable hydrogels have the potential to be applied broadly throughout the GI tract and other anatomic areas. By demonstrating the first use of light-degradable hydrogels in vivo, we provide biomedical engineers and clinicians with a previously unavailable, safe, dynamically deliverable, and precise tool to design dynamically actuated implantable devices.

scholarly journals Successful treatment of canine hemophilia by continuous expression of canine FVIIa

Blood ◽  
2009 ◽  
Vol 113 (16) ◽  
pp. 3682-3689 ◽  
Author(s):  
Paris Margaritis ◽  
Elise Roy ◽  
Majed N. Aljamali ◽  
Harre D. Downey ◽  
Urs Giger ◽  
...  
Keyword(s):  
Gene Transfer ◽  
Hemophilia A ◽  
Viral Vector ◽  
Canine Model ◽  
Factor Vii ◽  
Large Animal Model ◽  
Large Animal ◽  
Spontaneous Bleeding ◽  
Human Factor Viii

Abstract Continuous expression of activated factor VII (FVIIa) via gene transfer is a potential therapeutic approach for hemophilia patients with or without inhibitory antibodies to human factor VIII (FVIII) or IX (FIX). Here, we investigate whether gene transfer of an engineered canine FVIIa (cFVIIa) transgene can affect hemostasis in a canine model of hemophilia, a good predictor of efficacy of hemophilia treatments. Purified recombinant cFVIIa exhibited 12-fold higher tissue factor–dependent activity than purified recombinant zymogen cFVII. Subsequently, we generated a serotype 8 recombinant adeno-associated viral vector expressing cFVIIa from a liver-specific promoter. Vector delivery via the portal vein in hemophilia A and B dogs was well tolerated, and long-term expression of cFVIIa resulted in a shortening of the prothrombin time, partial correction of the whole blood clotting time and thromboelastography parameters, and a complete absence of spontaneous bleeding episodes. No evidence of hepatotoxicity, thrombotic complications, or inhibitory immune response was found. These data provide the first evidence for in vivo efficacy and safety of continuously expressed FVIIa as a FVIII/FIX-bypassing agent in a large animal model of hemophilia, avoiding the risk of inhibitor formation associated with bolus FVIII or FIX infusion.

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