Abstract 226: Recellularization of Xenograft Heart Valves Reduces the Xenoreactive Immune Response in an In Vivo Rat Model

2020 ◽  
Vol 127 (Suppl_1) ◽  
Author(s):  
Sabin J Bozso ◽  
Ryaan EL-Andari ◽  
Lin Fu Zhu ◽  
Benjamin Adam ◽  
Michael C Moon ◽  
...  
Keyword(s):  
Immune Response ◽  
Aortic Valve ◽  
Guinea Pig ◽  
Rat Model ◽  
Serum Immunoglobulin ◽  
Total Serum ◽  
Sprague Dawley ◽  
Cellular Infiltrate ◽  
Immunoglobulin Production

Background: Current xenograft valve constructs provoke an intense immune response that may lead to valve dysfunction. Our aim was to address the role of autologous mesenchymal stem cell (MSC) recellularization of xenogenic valves on the activation of the xenoreactive immune response in an in-vivo rat model. Methods: Explanted aortic valve constructs from female Hartley guinea pigs were procured and decellularized, followed by recellularization with syngeneic Sprague-Dawley rat MSCs. The recellularized aortic valve xenografts were then implanted into the infrarenal aorta of recipient female Sprague-Dawley rats. Grafts were implanted as either syngeneic grafts, non-decellularized (fresh), decellularized and recellularized xenografts. Rats were euthanized after 7-days, exsanguinated and the grafts explanted. Total serum immunoglobulin was quantified and histological analysis perfomed to analyze the immune response. Results: Overall survival to endpoint was significantly lower in the decellularized xenograft group (67%; 4/6), compared to fresh (100%; 6/6) and recellularized grafts (100%; 6/6). Similarly grafts in the decellularized group were more likely to have completely thrombosed (50%; 2/4), compared to fresh (33%; 2/6) and recellularized grafts (0%; 0/6). Decellularized guinea pig xenografts, when implanted into rats in-vivo , result in significantly reduced total serum immunoglobulin production and significantly reduced graft cellular infiltrate when compared to fresh xenografts. Moreover, when decellularized guinea pig xenografts were recellularized with syngeneic rat MSCs there was an additional decrease in total serum immunoglobulin production and graft cellular infiltrate when compared to both fresh and decellularized xenografts. Importantly, recellularized guinea pig xenografts had an equivalent total immunoglobulin production and graft cellular infiltrate when compared to syngeneic rat aortic valve controls. Conclusions: Autologous MSC recellularization of xenogenic valves reduces the xenoreactive immune response in an in-vivo rat model and may be an effective approach to decrease the progression of xenograft valve dysfunction.

Recellularization of xenograft heart valves reduces the xenoreactive immune response in an in vivo rat model

2021 ◽  
Author(s):  
Sabin J Bozso ◽  
Jimmy J H Kang ◽  
Ryaan EL-Andari ◽  
Nicholas Fialka ◽  
Lin Fu Zhu ◽  
...  
Keyword(s):  
Immune Response ◽  
T Cells ◽  
Stem Cell ◽  
Aortic Valve ◽  
Mesenchymal Stem Cell ◽  
Rat Model ◽  
Cell Infiltration ◽  
Immunoglobulin Production ◽  
Autologous Grafts

Abstract OBJECTIVES Our aim was to address the role of autologous mesenchymal stem cell recellularization of xenogenic valves on the activation of the xenoreactive immune response in an in vivo rat model. METHODS Explanted aortic valve constructs from female Hartley guinea pigs were procured and decellularized, followed by recellularization with autologous Sprague-Dawley rat mesenchymal stem cells. Aortic valve xenografts were then implanted into the infrarenal aorta of recipient rats. Grafts were implanted as either autologous grafts, non-decellularized (NGP), decellularized and recellularized xenografts (RGP). Rats were euthanized after 7 and 21 days and exsanguinated and the grafts were explanted. RESULTS The NGP grafts demonstrated significant burden of granulocytes (14.3 cells/HPF) and CD3+ T cells (3.9 cells/HPF) compared to the autologous grafts (2.1 granulocytes/HPF and 0.72 CD3+ T cells/HPF) after 7 days. A lower absolute number of infiltrating granulocytes (NGP vs autologous, 6.4 vs 2.4 cells/HPF) and CD3+ T cells (NGP vs autologous, 2.8 vs 0.8 cells/HPF) was seen after 21 days. Equivalent granulocyte cell infiltration in the RGP grafts (2.4 cells/HPF) compared to the autologous grafts (2.1 cells/HPF) after 7 and 21 days (2.8 vs 2.4 cells/HPF) was observed. Equivalent CD3+ T-cell infiltration in the RGP grafts (0.63 cells/HPF) compared to the autologous grafts (0.72 cells/HPF) after 7 and 21 days (0.7 vs 0.8 cells/HPF) was observed. Immunoglobulin production was significantly greater in the NGP grafts compared to the autologous grafts at 7 (123.3 vs 52.7 mg/mL) and 21 days (93.3 vs 71.6 mg/mL), with a similar decreasing trend in absolute production. Equivalent immunoglobulin production was observed in the RGP grafts compared to the autologous grafts at 7 (40.8 vs 52.7 mg/mL) and 21 days (29.5 vs 71.6 mg/mL). CONCLUSIONS Autologous mesenchymal stem cell recellularization of xenogenic valves reduces the xenoreactive immune response in an in vivo rat model and may be an effective approach to decrease the progression of xenograft valve dysfunction.

scholarly journals In Vivo Measurement of Neurochemical Abnormalities in the Hippocampus in a Rat Model of Cuprizone-Induced Demyelination

Diagnostics ◽  
2020 ◽  
Vol 11 (1) ◽  
pp. 45
Author(s):  
Do-Wan Lee ◽  
Jae-Im Kwon ◽  
Chul-Woong Woo ◽  
Hwon Heo ◽  
Kyung Won Kim ◽  
...  
Keyword(s):  
Magnetic Resonance ◽  
Rat Model ◽  
Resonance Spectroscopy ◽  
Chow Diet ◽  
Gamma Aminobutyric Acid ◽  
Sprague Dawley ◽  
In Vivo Measurement ◽  
Hippocampal Lesions ◽  
Total Creatine

This study quantitatively measured the changes in metabolites in the hippocampal lesions of a rat model of cuprizone-induced demyelination as detected using in vivo 7 T proton magnetic resonance spectroscopy. Nineteen Sprague Dawley rats were randomly divided into two groups and fed a normal chow diet or cuprizone (0.2%, w/w) for 7 weeks. Demyelinated hippocampal lesions were quantitatively measured using a 7 T magnetic resonance imaging scanner. All proton spectra were quantified for metabolite concentrations and relative ratios. Compared to those in the controls, the cuprizone-induced rats had significantly higher concentrations of glutamate (p = 0.001), gamma-aminobutyric acid (p = 0.019), and glutamate + glutamine (p = 0.001); however, creatine + phosphocreatine (p = 0.006) and myo-inositol (p = 0.001) concentrations were lower. In addition, we found that the glutamine and glutamate complex/total creatine (p < 0.001), glutamate/total creatine (p < 0.001), and GABA/total creatine (p = 0.002) ratios were significantly higher in cuprizone-treated rats than in control rats. Our results showed that cuprizone-induced neuronal demyelination may influence the severe abnormal metabolism in hippocampal lesions, and these responses could be caused by microglial activation, mitochondrial dysfunction, and astrocytic necrosis.

RECELLULARIZATION OF XENOGRAFT HEART VALVES REDUCES THE XENOREACTIVE IMMUNE RESPONSE IN AN IN-VIVO RAT MODEL

2020 ◽  
Vol 36 (10) ◽  
pp. S103
Author(s):  
S. Bozso ◽  
R. EL-Andari ◽  
L. Zhu ◽  
B. Adam ◽  
M. Moon ◽  
...  
Keyword(s):  
Immune Response ◽  
Rat Model ◽  
Heart Valves

scholarly journals THE SPECIFICITY OF ALLERGIC REACTIONS

1963 ◽  
Vol 117 (3) ◽  
pp. 401-423 ◽  
Author(s):  
John E. Coe ◽  
S. B. Salvin
Keyword(s):  
Immune Response ◽  
Guinea Pig ◽  
The State ◽  
Delayed Hypersensitivity ◽  
Protein Carrier ◽  
Specific Contact ◽  
Tolerant Animal ◽  
Gastric Feeding

"Gastric feeding" of adult guinea pigs with dinitrochlorobenzene (DCB) resulted in a specific unresponsiveness to sensitization with the specific contact hapten. The more DCB gastric-fed to a guinea pig, the more complete the unresponsiveness to the hapten. When mycobacteria were incorporated into the sensitizing emulsion, the state of unresponsiveness to the dinitrophenyl (DNP) group was less apparent. When animals gastric-fed with DCB were later sensitized with an in vitro conjugate of the hapten combined with a heterologous protein such as dinitrophenyl-hen egg albumin (DNP·HEA), an immune response similar to that in the controls occurred both to the hapten and to the protein carrier. However, when the tolerant animals were sensitized with a conjugate containing a homologous protein carrier such as dinitrophenyl guinea pig serum (DNP·GPS), they showed diminished immune responses in comparison with those in the non-tolerant controls. The presence of circulating anti-DNP antibodies from sensitization with DNP-HEA did not affect the unresponsiveness to the specific contact hapten, regardless of whether these antibodies are present before or after induction of tolerance. Sensitization with picryl chloride (PiCl) (a cross-reacting hapten), either before or after gastric feeding of DCB, did not affect the state of unresponsiveness to DNP. Similarly when the DNP-tolerant animal was sensitized with PiCl, the subsequent immune response was similar to that in the controls; cross-reactions with the DNP group both in the contact and circulating antibody phase occurred at a rate similar to that in the controls. The foregoing relationships can be explained by presuming that, upon the gastric feeding of DCB, an in vivo conjugate is formed with a somatic protein, which determines the basic specificity of the tolerance. Acquired tolerance seems to manifest an immunologic specificity similar to that of delayed hypersensitivity, a relationship not unexpected if delayed hypersensitivity is an early phase of the immune response.

Protection against ventricular arrhythmias and cardiac death using adenosine and lidocaine during regional ischemia in the in vivo rat

2004 ◽  
Vol 287 (3) ◽  
pp. H1286-H1295 ◽  
Author(s):  
Sarah J. Canyon ◽  
Geoffrey P. Dobson
Keyword(s):  
Infarct Size ◽  
Rat Model ◽  
Cardiac Death ◽  
Constant Infusion ◽  
Therapeutic Window ◽  
High Dose ◽  
Sprague Dawley ◽  
Myocardial Ischemia And Reperfusion ◽  
Regional Ischemia

Despite decades of research, there are few effective ways to treat ventricular fibrillation (VF), ventricular tachycardia (VT), or cardiac ischemia that show a significant survival benefit. Our aim was to investigate the combined therapeutic effect of two common antiarrhythmic compounds, adenosine and lidocaine (AL), on mortality, arrhythmia frequency and duration, and infarct size in the rat model of regional ischemia. Sprague-Dawley rats ( n = 49) were anesthetized with pentobarbital sodium (60 mg·ml−1·kg−1 ip) and instrumented for regional coronary occlusion (30 min) and reperfusion (120 min). Heart rate, blood pressure, and a lead II electrocardiogram were recorded. Intravenous pretreatment began 5 min before ischemia and extended throughout ischemia, terminating at the start of reperfusion. After 120 min, hearts were removed for infarct size measurement. Mortality occurred in 58% of saline controls ( n = 12), 50% of adenosine only (305 μg·kg−1·min−1, n = 8), 0% in lidocaine only (608 μg·kg−1·min−1, n = 8), and 0% in AL at any dose (152, 305, or 407 μg·kg−1·min−1 adenosine plus 608 μg·kg−1·min−1 lidocaine, n = 7, 8, and 6). VT occurred in 100% of saline controls (18 ± 9 episodes), 50% of adenosine-only (11 ± 7 episodes), 83% of lidocaine-only (23 ± 11 episodes), 60% of low-dose AL (2 ± 1 episodes, P < 0.05), 57% of mid-dose AL (2 ± 1 episodes, P < 0.05), and 67% of high-dose AL rats (6 ± 3 episodes). VF occurred in 75% of saline controls (4 ± 3 episodes), 100% of adenosine-only-treated rats (3 ± 2 episodes), and 33% lidocaine-only-treated rats (2 ± 1 episodes) of the rats tested. There was no deaths and no VF in the low- and mid-dose AL-treated rats during ischemia, and only one high-dose AL-treated rat experienced VF (25.5 sec). Infarct size was lower in all AL-treated rats but only reached significance with the mid-dose treatment (saline controls 61 ± 5% vs. 38 ± 6%, P < 0.05). We conclude that a constant infusion of a solution containing AL virtually abolished severe arrhythmias and prevented cardiac death in an in vivo rat model of acute myocardial ischemia and reperfusion. AL combinational therapy may provide a primary prevention therapeutic window in ischemic and nonischemic regions of the heart.

Electroacupuncture ameliorates corticotrophin-releasing factor-induced jejunal dysmotility in a rat model of stress

2020 ◽  
pp. 096452842092028
Author(s):  
Yu-Xue Zhao ◽  
Chang-Xiang Cui ◽  
Jun-Hong Gao ◽  
Jun Liu ◽  
Qun Liu ◽  
...  
Keyword(s):  
Rat Model ◽  
Gastrointestinal Transit ◽  
Receptor Subtype ◽  
Motor Disorder ◽  
Sprague Dawley ◽  
Functional Roles ◽  
Corticotrophin Releasing Factor ◽  
Sprague Dawley Rats ◽  
Gi Motility

Background Central injection of corticotrophin-releasing factor (CRF) mimics the effect of stress on gastrointestinal (GI) responses, including inhibition of GI motility. This study was designed to explore the effects of electroacupuncture (EA) on disordered jejunal motility in a rat model of stress induced by intracisternal (IC) injection of CRF. Methods A stress model was established by IC injection of CRF in Sprague–Dawley rats. GI motility was evaluated by assessing gastric emptying (GE), gastrointestinal transit (GIT) and jejunal motility in vivo. EA was performed at ST36. The functional roles of CRF receptor subtype 1 and subtype 2 (CRFr1 and CRFr2) were examined by IC administration of the corresponding selective CRF antagonists. Protein expression of CRFr1 and CRFr2 in the hypothalamus and jejunum was detected by Western blotting. Results IC injection of CRF significantly inhibited GE, GIT and jejunal motility. EA treatment remarkably improved the disturbed GI motility. Intriguingly, the disordered jejunal motility induced by central CRF was abolished by IC injection of a selective CRFr2 antagonist, indicating the essential role of central CRFr2 in mediating the stress-induced jejunal motor disorder. EA at ST36 decreased central and peripheral expression of CRFr2, which might be one of the potential mechanisms underlying the beneficial effect of EA on jejunal dysmotility in this rat model of stress. Conclusion This study suggested that EA at ST36 could ameliorate disordered jejunal motility induced by stress, and that this might be associated with the down-regulation of CRFr2.

scholarly journals Males and females exhibit distinct relationships between intervertebral disc degeneration and pain in a rat model

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Grace E. Mosley ◽  
Minghui Wang ◽  
Philip Nasser ◽  
Alon Lai ◽  
Daniel A. Charen ◽  
...  
Keyword(s):  
Sex Differences ◽  
Network Analysis ◽  
Intervertebral Disc ◽  
Rat Model ◽  
Biomechanical Testing ◽  
Sprague Dawley ◽  
Discogenic Pain ◽  
Males And Females ◽  
Ivd Degeneration

Abstract Back pain is linked to intervertebral disc (IVD) degeneration, but clinical studies show the relationship is complex. This study assessed whether males and females have distinct relationships between IVD degeneration and pain using an in vivo rat model. Forty-eight male and female Sprague–Dawley rats had lumbar IVD puncture or sham surgery. Six weeks after surgery, IVDs were evaluated by radiologic IVD height, histological grading, and biomechanical testing. Pain was assessed by von Frey assay and dorsal root ganglia (DRG) expression of Calca and Tac1 genes. Network analysis visualized which measures of IVD degeneration most related to pain by sex. In both females and males, annular puncture induced structural IVD degeneration, but functional biomechanical properties were similar to sham. Females and males had distinct differences in mechanical allodynia and DRG gene expression, even though sex differences in IVD measurements were limited. Network analysis also differed by sex, with more associations between annular puncture injury and pain in the male network. Sex differences exist in the interactions between IVD degeneration and pain. Limited correlation between measures of pain and IVD degeneration highlights the need to evaluate pain or nociception in IVD degeneration models to better understand nervous system involvement in discogenic pain.

scholarly journals The Effect of Sertoli Cells on Xenotransplantation and Allotransplantation of Ventral Mesencephalic Tissue in a Rat Model of Parkinson’s Disease

Cells ◽  
2019 ◽  
Vol 8 (11) ◽  
pp. 1420
Author(s):  
Yun-Ting Jhao ◽  
Chuang-Hsin Chiu ◽  
Chien-Fu F. Chen ◽  
Ta-Kai Chou ◽  
Yi-Wen Lin ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Rat Model ◽  
Sertoli Cells ◽  
Dopaminergic Neurons ◽  
Sprague Dawley ◽  
Drug Induced ◽  
In Vivo Evaluation ◽  
Ventral Mesencephalic

Intra-striatal transplantation of fetal ventral mesencephalic (VM) tissue has a therapeutic effect on patients with Parkinson’s disease (PD). Sertoli cells (SCs) possess immune-modulatory properties that benefit transplantation. We hypothesized that co-graft of SCs with VM tissue can attenuate rejection. Hemi-parkinsonian rats were generated by injecting 6-hydroxydopamine into the right medial forebrain bundle of Sprague Dawley (SD) rats. The rats were then intrastriatally transplanted with VM tissue from rats or pigs (rVM or pVM), with/without a co-graft of SCs (rVM+SCs or pVM+SCs). Recovery of dopaminergic function and survival of the grafts were evaluated using the apomorphine-induced rotation test and small animal-positron emission tomography (PET) coupled with [18F] DOPA or [18F] FE-PE2I, respectively. Immunohistochemistry (IHC) examination was used to determine the survival of the grafted dopaminergic neurons in the striatum and to investigate immune-modulatory effects of SCs. The results showed that the rVM+SCs and pVM+SCs groups had significantly improved drug-induced rotational behavior compared with the VM alone groups. PET revealed a significant increase in specific uptake ratios (SURs) of [18F] DOPA and [18F] FE-PE2I in the grafted striatum of the rVM+SCs and pVM+SCs groups as compared to that of the rVM and pVM groups. SC and VM tissue co-graft led to better dopaminergic (DA) cell survival. The co-grafted groups exhibited lower populations of T-cells and activated microglia compared to the groups without SCs. Our results suggest that co-graft of SCs benefit both xeno- and allo-transplantation of VM tissue in a PD rat model. Use of SCs enhanced the survival of the grafted dopaminergic neurons and improved functional recovery. The enhancement may in part be attributable to the immune-modulatory properties of SCs. In addition, [18F]DOPA and [18F]FE-PE2I coupled with PET may provide a feasible method for in vivo evaluation of the functional integrity of the grafted DA cell in parkinsonian rats.

scholarly journals Recellularization of Xenograft Heart Valves Reduces the Xenoreactive Immune Response in an In-Vivo Rat Model

2021 ◽  
Vol 40 (4) ◽  
pp. S299
Author(s):  
S.J. Bozso ◽  
R. EL-Andari ◽  
L. Zhu ◽  
B. Adam ◽  
M.C. Moon ◽  
...  
Keyword(s):  
Immune Response ◽  
Rat Model ◽  
Heart Valves

Abstract P107: Anti- Mir-510 In The Treatment Of Essential Hypertension By Using Hypertensive Rats

Hypertension ◽  
2021 ◽  
Vol 78 (Suppl_1) ◽  
Author(s):  
Auxzilia Preethi K ◽  
Sushmaa Chandralekha J.S ◽  
Durairaj sekar
Keyword(s):  
Gene Expression ◽  
Rat Model ◽  
Luciferase Assay ◽  
Sprague Dawley ◽  
Critical Pathways ◽  
Cardiac Tissues ◽  
In Vivo Experiments ◽  
Huvec Cells

Introduction: Hypertension (HTN) is one of the major public health complications throughout the world. Although progress has been made in HTN research, early diagnosis and treatment of HTN are yet to be flourished. MicroRNAs (miRNAs) are important post-transcriptional regulators of gene expression in many diseases including HTN. According to our previous report, there is direct evidence showing that miR-510 is involved in HTN. Hypothesis: We assessed the hypothesis that to decipher the critical pathways of miR-510 and PTEN in regulation of PI3K/AKT Pathways, so it can be used as a therapeutic pathway as well as biomarker. Finally, we intend to study how anti-miR-510 reduces the HTN in the hypertensive induced rat model. Methodology: Proliferation, migration, invasion and apoptosis capacity of miR-510, Anti-miR-510, PTEN and eNOS were evaluated in HUVEC Cells. The expression pattern of miR-510, anti-miR-510 and eNOS, PTEN are analyzed by qPCR and western blot The relationship between miR-510, Anti-miR-510 and PTEN are investigated by luciferase assay Deoxycorticosterone acetate (DOCA) of 70mg/kg and 1% NaCl salt induced hypertension model (Sprague Dawley rats) was used in this study. According to the dose dependent study, anti-miR-510 was administered intravenously. Histological analyses are performed to examine the hypertrophy by using cardiac tissues fixed in 1% paraformaldehyde. Results and conclusion: Our results suggested that miR-510 can directly influence the PTEN expressions in HUVEC cells. Furthermore, the in vitro experiments clearly indicated that miR-510/PI3K/AKT/PTEN axis involved in HTN. Anti-miR-510 delivery can reduce the progression of HTN in the hypertensive induced rat model. Though miR-510 is involved in HTN, but its molecular mechanism is almost unknown. So, these analyses suggested that the correlation between miR-510, PTEN, anti-miR-510 are the critical step in gene expression and regulations. Thus, all these analyses could lead in identification of therapeutic target and non-invasive biomarker for HTN. Our in vivo experiments suggesting that anti-miR-510 may act as a novel therapeutic molecule for HTN treatment.

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