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BACKGROUND: Some clinical trials have shown the usefulness of stem cell therapy for diabetic foot ulcers. However, the donor supply is limited, and the process is time consuming and expensive. This study assessed the therapeutic effects of neonatal porcine bone marrow-derived mesenchymal stem cell (npBM-MSC) xenotransplantation using diabetic wound model mice. METHODS: All layers of back skin were removed from streptozotocin-induced diabetic mice. In the npBM-MSCs group, npBM-MSCs were transplanted to the wound, and syngeneic mouse bone marrow-derived mesenchymal stem cells (mBM-MSCs) were transplanted to the wound in the mBM-MSCs group. The control group comprised diabetic mice that did not receive cellular therapy. The therapeutic effects of the transplantation were evaluated according to the rate of wound closure and the promotion of neovascularization in the wound. RESULTS: The wound closure rate was significantly improved in the npBM-MSCs group compared with the control group (p < .001 at postoperative day [POD] 4 and p < .01 at POD 7) and mBM-MSCs groups (p < .05 at POD 4). Prominent promotion of both angiogenesis and lymphangiogenesis was observed in the npBM-MSCs group. Furthermore, the expression of murine Prox1 and both porcine and murine Vegfs and Tgfb1 in the wounds was enhanced until POD 4 by npBM-MSCs transplantation. The amounts of vascular endothelial growth factor (VEGF) A, VEGFC, and transforming growth factor ß1 secreted from npBM-MSCs were higher than those from mBM-MSCs (p < .05). CONCLUSION: Xenotransplantation of npBM-MSCs improved diabetic wound healing by promoting both angiogenesis and lymphangiogenesis.
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Diabetes Mellitus Experimental , Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Medula Óssea/metabolismo , Diabetes Mellitus Experimental/terapia , Linfangiogênese , Camundongos , Suínos , Transplante Heterólogo , Fator A de Crescimento do Endotélio Vascular/metabolismo , CicatrizaçãoRESUMO
BACKGROUND: The clinical utility of stem cell therapy for peripheral artery disease has not been fully discussed, and one obstacle is limited donor supplies. In this study, we attempted to rescue mouse ischemic hind limb by xenotransplantation of neonatal porcine bone marrow-derived mesenchymal stem cells (npBM-MSCs). METHODS: Neonatal porcine bone marrow-derived mesenchymal stem cells were transplanted to ischemic hind limbs of male C57BL/6J mice (npBM-MSCs group). Mice with syngeneic transplantation of mouse BM-MSCs (mBM-MSCs group) were also prepared for comparison. The angiogenic effects were evaluated by recovery of blood flow on laser Doppler imaging, histologic findings, and genetic and protein levels of angiogenic factors. RESULTS: Regarding laser Doppler assessments, blood flow in the hind limb was rapidly recovered in the npBM-MSCs group, compared with that in the mBM-MSCs group (P = .016). Compared with the mBM-MSCs group, the npBM-MSCs group had early and prominent lymphangiogenesis [P < .05 on both post-operative days (PODs) 3 and 7] but had similar angiogenesis. Regarding genomic assessments, xenotransplantation of npBM-MSCs enhanced the expressions of both porcine and murine Vegfc in the hind limbs by POD 3. Interestingly, the level of murine Vegfc expression was significantly higher in the npBM-MSCs group than in the mBM-MSCs group on PODs 3 and 7 (P < .001 for both). Furthermore, the secreted VEGFC protein level was higher from npBM-MSCs than from mBM-MSCs (P < .001). CONCLUSION: Xenotransplantation of npBM-MSCs contributed to the improvement of hind limb ischemia by both angiogenesis and lymphangiogenesis, especially promotion of the latter. npBM-MSCs may provide an alternative to autologous and allogeneic MSCs for stem cell therapy of critical limb ischemia.
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Transplante de Células-Tronco Mesenquimais , Células-Tronco Mesenquimais , Animais , Medula Óssea , Isquemia/terapia , Linfangiogênese , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Suínos , Transplante HeterólogoRESUMO
BACKGROUND: Genetically modified pigs (GMP) have been developed to alleviate the shortage of donors in human islet transplantation and rejection. In this study, we characterized and compared the islets from GalTKO, GalTKO/hCD46, GalTKO/hCD46/hCD39, and wild-type (WT) neonatal pigs. METHODS: Islets were isolated from GMP and WT pig pancreases that have been packaged with ice pack for at least 24 hours. The difference in gene expression and function of islets were evaluated by microarray analysis and transplantation of islets under the kidney capsule of streptozotocin-induced diabetic immune-deficient mice, respectively. Blood glucose levels of these mice were monitored weekly post-transplantation for >100 days, and islet grafts were collected and evaluated for the presence of endocrine cells. RESULTS: The genes involved in extracellular components, cell adhesion, glucose metabolism, and inflammatory response are differentially expressed between GMP and WT pig islets. Variation in the ability of pig islets in correcting the diabetic state of the mouse recipients appears to be dependent on the pig donor. In addition, prolonged cold ischemia time had a negative effect on the transplant outcome. All normoglycemic mice were able to respond well to glucose challenge despite the initial differences in the ability of islet transplants to reverse their diabetic state. Islet xenografts of normoglycemic mice contained abundant insulin- and glucagon-positive cells. CONCLUSION: The effect of GMP and WT neonatal pig islet transplants on hyperglycemia in mice appears to be dependent on the pig donor, and prolonged cold ischemia time negatively affects the neonatal pig islet transplant outcome.
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Diabetes Mellitus Experimental , Transplante das Ilhotas Pancreáticas , Ilhotas Pancreáticas , Animais , Isquemia Fria , Camundongos , Pâncreas , Transplante HeterólogoRESUMO
Myogenic response, a phenomenon in which resistance size arteries and arterioles swiftly constrict or dilate in response to an acute elevation or reduction, respectively, in intravascular pressure is a key component of renal autoregulation mechanisms. Although it is well established that the renal system is functionally immature in neonates, mechanisms that regulate neonatal renal blood flow (RBF) remain poorly understood. In this study, we investigated the hypothesis that members of the transient receptor potential vanilloid (TRPV) channels are molecular components of renal myogenic constriction in newborns. We show that unlike TRPV1-3, TRPV4 channels are predominantly expressed in neonatal pig preglomerular vascular smooth muscle cells (SMCs). Intracellular Ca2+ concentration ([Ca2+]i) elevation induced by osmotic cell swelling was attenuated by TRPV4, L-type Ca2+, and stretch-activated Ca2+ channel blockers but not phospholipase A2 inhibitor. Blockade of TRPV4 channels reversed steady-state myogenic tone and inhibited pressure-induced membrane depolarization, [Ca2+]i elevation, and constriction in distal interlobular arteries. A step increase in arterial pressure induced efficient autoregulation of renal cortical perfusion and total RBF in anesthetized and mechanically ventilated neonatal pigs. Moreover, intrarenal arterial infusion of the TRPV4 channel blockers HC 067047 and RN 1734 attenuated renal autoregulation in the pigs. These data suggest that renal myogenic autoregulation is functional in neonates. Our findings also indicate that TRPV4 channels are mechanosensors in neonatal pig preglomerular vascular SMCs and contribute to renal myogenic autoregulation.
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Rim/metabolismo , Desenvolvimento Muscular/fisiologia , Músculo Liso Vascular/fisiologia , Miócitos de Músculo Liso/metabolismo , Canais de Cátion TRPV/metabolismo , Animais , Animais Recém-Nascidos , Pressão Sanguínea/fisiologia , Rim/irrigação sanguínea , Masculino , Artéria Renal/metabolismo , Circulação Renal/fisiologia , SuínosRESUMO
BACKGROUND: Hepatocyte transplantation is a promising therapy for acute liver failure. Cell therapy using xenogeneic sources has emerged as an alternative treatment for patients with organ failure due to the shortage of transplantable human organs. The purpose of this study was to improve the survival of mice with acute liver failure by transplanting encapsulated neonatal pig re-aggregated liver cells (NPRLC). METHODS: Liver injury was induced in C57/BL6 male mice by the injection of 600 mg/kg of acetaminophen. Xenogeneic liver cells were isolated from a neonatal pig and processed via re-aggregation and encapsulation to improve the efficiency of the xenogeneic liver cell transplantation. The neonatal pig liver showed abnormal lobule structure. Isolated cells were re-aggregated and intraperitoneally transplanted into acute liver failure mice models. RESULTS: Re-aggregated cells showed significantly enhanced viability and significantly greater synthesis of albumin and urea than cells cultured in monolayers. Further, we observed improved serum levels of ALT/AST, and the survival rate of mice with acute liver failure was improved by the intraperitoneal transplantation of encapsulated hepatocytes (48,000 equivalent (Eq) per mouse). CONCLUSIONS: This study shows that using encapsulated NPRLCs improves the efficacy of xenogeneic liver cell transplantation for the treatment of mice with acute liver failure. Therefore, this may be a good strategy for bridge therapy for the treatment of acute liver failure in humans.
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Hepatócitos/transplante , Falência Hepática Aguda/terapia , Transplante Heterólogo/métodos , Acetaminofen/toxicidade , Albuminas/biossíntese , Animais , Animais Recém-Nascidos , Agregação Celular , Sobrevivência Celular , Células Cultivadas , Modelos Animais de Doenças , Sobrevivência de Enxerto , Hepatócitos/citologia , Hepatócitos/metabolismo , Humanos , Falência Hepática Aguda/induzido quimicamente , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Esferoides Celulares/transplante , Sus scrofa , Suínos , Porco Miniatura , Ureia/metabolismoRESUMO
Non-alcoholic fatty liver disease (NAFLD) is a range of disorders characterized by lipid accumulation in hepatocytes. Although this spectrum of disorders is associated with adult obesity, recent evidence suggests that this condition could also occur independently of obesity, even in children. Previously, we reported that pigs fed a formula containing medium-chain fatty acids (MCFAs) developed hepatic steatosis and weighed less than those fed an isocaloric formula containing long-chain fatty acids (LCFAs). Our objective was to determine the association between NAFLD and the skeletal muscle transcriptome in response to energy and lipid intake. Neonatal pigs were fed one of three formulas: a control formula (CONT, n = 6) or one of two isocaloric high-energy formulas containing either long (LCFA, n = 6) or medium (MCFA, n = 6) chain fatty acids. Pigs were fed for 22 d, and tissues were collected. Body weight at 20 and 22 d was greater for LCFA-fed pigs than their CONT or MCFA counterparts (p < 0.005). Longissimus dorsi weight was greater for LCFA compared with MCFA, while CONT was intermediate (p < 0.05). Lean gain and protein deposition were greater for LCFA than for CONT and MCFA groups (p < 0.01). Transcriptomic analysis revealed 36 differentially expressed genes (DEGs) between MCFA and LCFA, 53 DEGs between MCFA and CONT, and 52 DEGs between LCFA and CONT (FDR < 0.2). Feeding formula high in MCFAs resulted in lower body and muscle weights. Transcriptomics data suggest that the reduction in growth was associated with a disruption in cholesterol metabolism in skeletal muscles.
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Fifty gilts (initial body weight [BW] 190.7â ±â 4.2 kg) were recruited on day 85 of gestation and were used until day 19 of lactation to assess the dose-response of inactivated yeast via hydrolyzation (HY) inclusion on offspring growth and immunoglobulin (Ig) transfer prior to weaning. Gilts were assigned to one of the 5 experimental diets: a control with no HY (HY0) or inclusion of 0.25% (HY0.25), 0.5% (HY0.5), 1.0% (HY1.0), or 1.2% (HY1.2) HY. Gilts were weighed on days 85 and 110 of gestation and days 1 and 19 (weaning) after farrowing. Offspring were weighed on days 1 and 19 of age. On lactation day 1 (approximately 24 h after farrowing), colostrum, gilt plasma, and plasma from 2 median BW piglets were collected and on day 19, plasma from each gilt and 2 median BW piglets per litter were collected for determination of Ig concentrations. Contrast statements were used to assess the linear, quadratic, cubic, and quartic effects of HY inclusion. The inclusion of HY had minimal effects on gilt BW or litter characteristics at birth (total number born and born alive, piglet birth weight). Lactation average daily feed intake of the gilts tended to increase then decrease with increasing HY inclusion (quadratic; Pâ =â 0.085). Piglet preweaning average daily gain (linear, quadratic, and quartic; Pâ <â 0.05) and BW at weaning (quadratic and quartic; Pâ <â 0.05) increased then decreased with increasing HY inclusion. On lactation day 1, colostrum and gilt plasma Ig concentrations were not affected by dietary treatment (Pâ >â 0.10) but piglet IgA and IgM decreased then increased with HY inclusion level (cubic; Pâ <â 0.05). On lactation day 19, piglet plasma IgG tended to increase with HY inclusion (linear; Pâ =â 0.099). In summary, increasing HY inclusion in late gestating and lactating gilt diets improved immune transfer in the first 24 h after birth and piglet preweaning growth rates and BW at weaning. Therefore, maternal feeding of HY could be used as a strategy to improve offspring immunocompetence and BW at weaning, with possible carryover benefits for the postweaning phase.
Abrupt weaning exposes piglets to various stressors that result in a period after weaning with little or no weight gain or feed intake and increased incidence of morbidity and mortality. Inactivated yeast via hydrolyzation (HY) is a functional feed additive that can improve the immune response in pigs. The low and variable feed intakes immediately after weaning render feed additives less useful in nursery pig diets, therefore, enhancing immunocompetence prior to weaning could be a strategy to improve offspring outcomes. This study tested 4 levels of HY (0.25%, 0.5%, 1.0%, and 1.2%) and control (0%) fed to gestating and lactating gilts from day 85 of gestation until day 19 of lactation when piglets were weaned. Plasma immunoglobulin (Ig) concentrations and preweaning offspring growth rates were assessed. It was found that piglet preweaning average daily gain and body weight at weaning were improved with increasing inclusion of HY in the maternal diet, which corresponded to increased plasma IgA and IgM concentrations for the offspring after birth. Greater body weight at weaning and greater plasma IgA and IgM concentration have the potential to attenuate the postweaning growth lag in addition to improving immunocompetence around weaning.
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Ração Animal , Dieta , Lactação , Animais , Feminino , Lactação/fisiologia , Ração Animal/análise , Gravidez , Dieta/veterinária , Suínos/crescimento & desenvolvimento , Suínos/fisiologia , Suínos/imunologia , Desmame , Colostro , Imunoglobulinas/sangue , Imunoglobulinas/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Relação Dose-Resposta a DrogaRESUMO
Cyclooxygenase (COX)-2 is the major constitutively expressed COX isoform in the newborn brain. COX-2 derived prostanoids and reactive oxygen species appear to play a major role in the mechanism of perinatal hypoxic-ischemic injury in the newborn piglet, an accepted animal model of the human term neonate. The study aimed to quantitatively determine COX-2 immunopositive neurons in different brain regions in piglets under normoxic conditions (n=15), and 4 hours after 10 min asphyxia (n=11). Asphyxia did not induce significant changes in neuronal COX-2 expression of any studied brain areas. In contrast, there was a marked regional difference in all experimental groups. Thus, significant difference was observed between fronto-parietal and temporo-occipital regions: 59±4% and 67±3% versus 41±2%* and 31±3%* respectively (mean±SEM, data are pooled from all subjects, n=26, *p<0.05, vs. fronto-parietal region). In the hippocampus, COX-2 immunopositivity was rare (highest expression in CA1 region: 14±2%). The studied subcortical areas showed negligible COX-2 staining. Our findings suggest that asphyxia does not significantly alter the pattern of neuronal COX-2 expression in the early reventilation period. Furthermore, based on the striking differences observed in cortical neuronal COX-2 distribution, the contribution of COX-2 mediated neuronal injury after asphyxia may also show region-specific differences.
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BACKGROUND: Cystic hygromas (lymphangiomas) are rarely reported in various animal species, humans included. A hygroma is a benign congenital malformation of the lymphatic drainage system, presenting itself as a mass consisting of multiple cysts of various sizes with a watery content. CASE PRESENTATION: This report describes clinical, ultrasonographic, and post-mortem findings of a cystic hygroma in a suckling pig. The mass was characterized by a few thin-walled cysts, containing clear yellow serous fluid. Histologically, the central cavity was lined by a single layer of squamous cells, supported by a thick fibrous stroma. On immunohistochemistry, scattered lining cells were weakly positive for Factor-VIII, suggesting their possible endothelial origin. CONCLUSIONS: This case report contributes to raising awareness on this condition in pigs allowing early identification in life so that appropriate care can be provided. The case report attributes to science on hygromas in general, as better understanding of pathologic features, the aetiology and appropriate treatment are needed.
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The yield, cell composition, and function of islets isolated from various ages of neonatal pigs were characterized using in vitro and in vivo experimental models. Islets from 7- and 10-day-old pigs showed significantly better function both in vitro and in vivo compared to islets from 3- and 5-day-old pigs however, the islet yield from 10-day-old pigs were significantly less than those obtained from the other pigs. Since islets from 3-day-old pigs were used in our previous studies and islets from 7-day-old pigs reversed diabetes more efficiently than islets from other groups, we further evaluated the function of these islets post-transplantation. B6 rag-/- mouse recipients of various numbers of islets from 7-day-old pigs achieved normoglycemia faster and showed significantly improved response to glucose challenge compared to the recipients of the same numbers of islets from 3-day-old pigs. These results are in line with the findings that islets from 7-day-old pigs showed reduced voltage-dependent K+ (Kv) channel activity and their ability to recover from post-hypoxia/reoxygenation stress. Despite more resident immune cells and immunogenic characteristics detected in islets from 7-day-old pigs compared to islets from 3-day-old pigs, the combination of anti-LFA-1 and anti-CD154 monoclonal antibodies are equally effective at preventing the rejection of islets from both age groups of pigs. Collectively, these results suggest that islets from various ages of neonatal pigs vary in yield, cellular composition, and function. Such parameters may be considered when defining the optimal pancreas donor for islet xenotransplantation studies.
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Diabetes Mellitus , Transplante das Ilhotas Pancreáticas , Animais , Suínos , Camundongos , Transplante das Ilhotas Pancreáticas/métodos , Pâncreas , Transplante Heterólogo/métodosRESUMO
Researchers have shown that adult zebrafish have the potential to regenerate 20% of the ventricular muscle within two months of apex resection, and neonatal mice have the capacity to regenerate their heart after apex resection up until day 7 after birth. The goal of this study was to determine if large mammals (porcine heart model) have the capability to fully regenerate a resected portion of the left ventricular apex during the neonatal stage, and if so, how long the regenerative potential persists. A total of 36 piglets were divided into the following groups: 0-day control and surgical groups and seven-day control and surgical groups. For the apex removal groups, each piglet was subjected to a partial wall thickness resection (~30% of the ventricular wall thickness). Heart muscle function was assessed via transthoracic echocardiograms; the seven-day surgery group experienced a decrease in ejection fraction and fractional shortening. Upon gross necropsy, for piglets euthanized four weeks post-surgery, all 0-day-old hearts showed no signs of scarring or any indication of the induced injury. Histological analysis confirmed that piglets in the 0-day surgery group exhibited various degrees of regeneration, with half of the piglets showing full regeneration and the other half showing partial regeneration. However, each piglet in the seven-day surgery group demonstrated epicardial fibrosis along with moderate to severe dissecting interstitial fibrosis, which was accompanied by an abundant collagenous extracellular matrix as the result of a scar formation in the resection site. Histology of one 0-day apex resection piglet (briefly lain on and accidentally killed by the mother sow three days post-surgery) revealed dense, proliferative mesenchymal cells bordering the fibrin and hemorrhage zone and differentiating toward immature cardiomyocytes. We further examined the heart explants at 5-days post-surgery (5D PO) and 1-week post-surgery (1W PO) to assess the repair progression. For the 0-day surgery piglets euthanized at 5D PO and 1W PO, half had abundant proliferating mesenchymal cells, suggesting active regeneration, while the other half showed increased extracellular collagen. The seven-day surgery piglets euthanized at 5D PO, and 1W PO showed evidence of greatly increased extracellular collagen, while some piglets had proliferating mesenchymal cells, suggesting a regenerative effort is ongoing while scar formation seems to predominate. In short, our qualitative findings suggest that the piglets lose the full myocardial regenerative potential by 7 days after birth, but greatly preserve the regenerative potential within 1 day post-partum.
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Replacement of ß cells is only a curative approach for type 1 diabetes (T1D) patients to avoid the threat of iatrogenic hypoglycemia. In this pursuit, islet allotransplantation under Edmonton's protocol emerged as a medical miracle to attain hypoglycemia-free insulin independence in T1D. Shortage of allo-islet donors and post-transplantation (post-tx) islet loss are still unmet hurdles for the widespread application of this therapeutic regimen. The long-term survival and effective insulin independence in preclinical studies have strongly suggested pig islets to cure overt hyperglycemia. Importantly, CRISPR-Cas9 technology is pursuing to develop "humanized" pig islets that could overcome the lifelong immunosuppression drug regimen. Lately, induced pluripotent stem cell (iPSC)-derived ß cell approaches are also gaining momentum and may hold promise to yield a significant supply of insulin-producing cells. Theoretically, personalized ß cells derived from a patient's iPSCs is one exciting approach, but ß cell-specific immunity in T1D recipients would still be a challenge. In this context, encapsulation studies on both pig islet as well as iPSC-ß cells were found promising and rendered long-term survival in mice. Oxygen tension and blood vessel growth within the capsules are a few of the hurdles that need to be addressed. In conclusion, challenges associated with both procedures, xenotransplantation (of pig-derived islets) and stem cell transplantation, are required to be cautiously resolved before their clinical application.
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Diabetes Mellitus Tipo 1 , Transplante das Ilhotas Pancreáticas , Animais , Camundongos , Diabetes Mellitus Tipo 1/terapia , Transplante das Ilhotas Pancreáticas/métodos , Insulina , Transplante Heterólogo/métodos , Células-TroncoRESUMO
Vaccination of neonatal pigs could be supportive to prevent porcine reproductive and respiratory syndrome virus (PRRSV), which is an important porcine pathogen causing worldwide welfare and health problems in pigs of different age classes. However, neonatal immunity substantially differs to adults, thus different vaccines may be required in neonateal pigs. We examined if the immunogenicity and efficacy of inactivated PRRSV (iPRRSV) vaccines in neonatal pigs could be improved with adjuvants containing oil-in water (O/W) emulsions with or without Toll-like receptor (TLR) agonists and by altering the delivery route from intramuscular (i.m.) to the skin. Three-day-old PRRSV-naïve piglets (n = 54, divided in 6 groups) received a prime vaccination and a booster vaccination four weeks later. The vaccine formulations consisted of different O/W emulsions (Montanide™ ISA28RVG (ISA28)), a squalene in water emulsion (SWE) for i.m. or a Stable Emulsion (SE) with squalene for skin vaccination) and/or a mixture of TLR1/2, 7/8 and 9 agonists (TLRa) combined with iPRRSV strain 07V063. These vaccines were delivered either i.m. (ISA28, SWE, TLRa or SWE + TLRa) or into the skin (skiSE + TLRa) with dissolving microneedle (DMN)-patches. All animals received a challenge with homologous PRRSV three weeks after booster vaccination. Specific antibodies, IFN-γ production and viremia were measured at several time-points after vaccination and/or challenge, while lung pathology was studied at necropsy. After booster vaccination, only ISA28 induced a specific antibody response while a specific T-cell IFN-γ response was generated in the SWE group, that was lower for ISA28, and absent in the other groups. This suggests that prime vaccination in neonates induced a specific immune response after booster vaccination, dependent on the emulsion formulation, but not dependent on the presence of the TLRa or delivery route. Despite the measured immune responses none of the vaccines showed any efficacy. Further research focused on the early immune response in draining lymph nodes is needed to elucidate the potential of TLR agonists in vaccines for neonatal pigs.
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Adjuvantes Imunológicos/farmacologia , Imunogenicidade da Vacina , Síndrome Respiratória e Reprodutiva Suína/prevenção & controle , Vírus da Síndrome Respiratória e Reprodutiva Suína/imunologia , Vacinas Virais/imunologia , Animais , Animais Recém-Nascidos , Citocinas/sangue , Imunidade Celular , Pulmão/patologia , Linfócitos/imunologia , Masculino , Síndrome Respiratória e Reprodutiva Suína/imunologia , Síndrome Respiratória e Reprodutiva Suína/patologia , Suínos , Vacinas de Produtos Inativados/imunologia , Viremia/veterináriaRESUMO
The acute cell-mediated immune response presents a significant barrier to xenotransplantation. Immune-privileged Sertoli cells (SC) can prolong the survival of co-transplanted cells including xenogeneic islets, hepatocytes, and neurons by protecting them from immune rejection. Additionally, SC survive as allo- and xenografts without the use of any immunosuppressive drugs suggesting elucidating the survival mechanism(s) of SC could be used to improve survival of xenografts. In this study, the survival and immune response generated toward neonatal pig SC (NPSC) or neonatal pig islets (NPI), nonimmune-privileged controls, was compared after xenotransplantation into naïve Lewis rats without immune suppression. The NPSC survived throughout the study, while NPI were rejected within 9 days. Analysis of the grafts revealed that macrophages and T cells were the main immune cells infiltrating the NPSC and NPI grafts. Further characterization of the T cells within the grafts indicated that the NPSC grafts contained significantly more cluster of differentiation 4 (CD4) and cluster of differentiation 8 (CD8) regulatory T cells (Tregs) at early time points than the NPI grafts. Additionally, the presence of increased amounts of interleukin 10 (IL-10) and transforming growth factor (TGF) ß and decreased levels of tumor necrosis factor (TNF) α and apoptosis in the NPSC grafts compared to NPI grafts suggests the presence of regulatory immune cells in the NPSC grafts. The NPSC expressed several immunoregulatory factors such as TGFß, thrombospondin-1 (THBS1), indoleamine-pyrrole 2,3-dioxygenase, and galectin-1, which could promote the recruitment of these regulatory immune cells to the NPSC grafts. In contrast, NPI grafts had fewer Tregs and increased apoptosis and inflammation (increased TNFα, decreased IL-10 and TGFß) suggestive of cytotoxic immune cells that contribute to their early rejection. Collectively, our data suggest that a regulatory graft environment with regulatory immune cells including CD4 and CD8 Tregs in NPSC grafts could be attributed to the prolonged survival of the NPSC xenografts.
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Antígenos CD4/metabolismo , Antígenos CD8/metabolismo , Células de Sertoli/metabolismo , Linfócitos T Reguladores/metabolismo , Transplante Heterólogo/métodos , Animais , Animais Recém-Nascidos , Masculino , Células de Sertoli/citologia , SuínosRESUMO
This study aimed to investigate the effects of early intervention with antibiotics and maternal fecal microbiota on ileal morphology and barrier function, and transcriptomic profiling in neonatal piglets. Piglets in the amoxicillin (AM), fecal microbiota transplantation (FMT), and control (CO) groups were orally administrated with amoxicillin solution (6.94 mg/mL), maternal fecal microbiota suspension [>109 colony forming unit (CFU)/mL], and physiological saline, respectively. Compared with the CO group, early intervention with AM or FMT significantly decreased ileal crypt depth on day 7 and altered gene expression profiles in ileum on days 7 and 21, and especially promoted the expression of chemokines (CCL5, CXCL9, and CXCL11) involved in the toll-like receptor signaling pathway on day 21. FMT changed major immune activities from B cell immunity on day 7 to T cell immunity on day 21 in the ileum. On the other hand, both AM and FMT predominantly downregulated the gene expression of toll-like receptor 4 (TLR4). In summary, both early interventions modulated intestinal barrier function and immune system in the ileum with a low impact on ileal morphology and development.
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Porcine growth hormone (pGH) is most important hormone which is involved in the growth and development of pig. However, a series of studies have indicated that neonatal pig is insensitive to pGH; the reason for this phenomenon is still not fully understood. In this work, we try to investigate this issue from the angle of intracellular signaling induced by pGH. In the present study, porcine hepatocytes from neonatal pig were used as a model, and confocal laser scanning microscopy (CLSM), Western blot, co-immunoprecipitation and colocalization assay were used to study pGH's signaling properties in hepatocytes of neonatal pig and explore the possible mechanism(s) for why intracellular signaling is insensitive to pGH. The results indicated that Janus kinase 2 and signal transducers and activators of transcription 5/3/1 (JAK2-STATs) signaling are not activated. We further investigated the possible mechanism(s) by which JAK2-STATs' signaling is not activated by pGH and growth hormone receptor (GHR) and found that the negative regulatory molecules of JAK2-STATs signaling may be associated with this phenomenon in the hepatocytes of neonatal pig. In addition, we also explored pGH's biology in hepatocytes from neonatal pig, it can be found that pGH/GHR could translocate into the cell nucleus, which implies that pGH/GHR may exhibit physiological roles based on their nuclear localization. We found that pGH could not trigger intracellular signaling in the hepatocytes of neonatal pigs, but not young pigs, which provides an important explanation for why the growth of neonatal pig is GH independent.
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Skeletal muscle growth during the early postnatal period is rapid in the pig and dependent on the capacity of muscle to respond to anabolic and catabolic stimuli. Muscle mass is driven by the balance between protein synthesis and degradation. Among these processes, muscle protein synthesis in the piglet is exceptionally sensitive to the feeding-induced postprandial changes in insulin and amino acids, whereas muscle protein degradation is affected only during specific catabolic states. The developmental decline in the response of muscle to feeding is associated with changes in the signaling pathways located upstream and downstream of the mechanistic target of rapamycin protein complex. Additionally, muscle growth is supported by an accretion of nuclei derived from satellite cells. Activated satellite cells undergo proliferation, differentiation, and fusion with adjacent growing muscle fibers. Enhancing early muscle growth through modifying protein synthesis, degradation, and satellite cell activity is key to maximizing performance, productivity, and lifelong pig health.
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Músculo Esquelético/crescimento & desenvolvimento , Suínos/crescimento & desenvolvimento , Animais , Animais Recém-Nascidos/crescimento & desenvolvimento , Modelos Animais , Proteínas Musculares/biossíntese , Músculo Esquelético/metabolismo , Células Satélites de Músculo Esquelético/citologia , Transdução de Sinais , Suínos/metabolismo , Serina-Treonina Quinases TOR/metabolismoRESUMO
We investigated the effects of early intervention with maternal fecal microbiota and antibiotics on gut microbiota and the metabolites. Five litters of healthy neonatal piglets (Duroc × Landrace × Yorkshire, nine piglets in each litter) were used. Piglets in each litter were orally treated with saline (CO), amoxicillin treatment (AM), or maternal fecal microbiota transplantation (MFMT) on days 1â»6, with three piglets in each treatment. Results were compared to the CO group. MFMT decreased the relative abundances of Clostridium sensu stricto and Parabacteroides in the colon on day 7, whereas the abundance of Blautia increased, and the abundance of Corynebacterium in the stomach reduced on day 21. AM reduced the abundance of Arcanobacterium in the stomach on day 7 and reduced the abundances of Streptococcus and Lachnoclostridium in the ileum and colon on day 21, respectively. The metabolite profile indicated that MFMT markedly influenced carbohydrate metabolism and amino acid (AA) metabolism on day 7. On day 21, carbohydrate metabolism and AA metabolism were affected by AM. The results suggest that MFMT and AM discriminatively modulate gastrointestinal microflora and alter the colonic metabolic profiles of piglets and show different effects in the long-term. MFMT showed a location-specific influence on the gastrointestinal microbiota.
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BACKGROUND: Early outcome predictors after delivery room cardiopulmonary resuscitation (CPR) of asphyxiated newborns are needed. OBJECTIVES: To investigate if cerebral (rScO2) and renal (rSrO2) tissue oxygen saturation 30 min after return of spontaneous circulation (ROSC) are different between surviving versus nonsurviving piglets with asphyxia-induced cardiac arrest and CPR. Further, to investigate the relationship of rScO2 and rSrO2 to cardiac output (CO), blood pressure (BP), and biochemical variables 30 min and 4 h after ROSC. METHODS: Anesthetized, mechanically ventilated piglets (1-3 days, 1.7-2.4 kg) were used. rScO2, rSrO2, SpO2, right common carotid artery flow, and arterial BP were measured continuously. CO was measured with echocardiography. The piglets were asphyxiated until cardiac arrest and resuscitated. Piglets that survived 4 h after ROSC (n = 12) were compared with piglets that died before planned euthanasia at 4 h (n = 13). Left ventricular, and kidney and brain tissue lactate were analyzed. Correlations between variables were assessed. RESULTS: Thirty minutes after ROSC, median rSrO2 (43% [n = 10] vs. 25% [n = 2], p = 0.003) but not rScO2 (46% [41-55] [n = 10] vs. 40% [22-45] [n = 5], p = 0.08) was higher in survivors than in nonsurvivors. Arterial lactate was negatively correlated and pH positively correlated with rScO2 and rSrO2. Left ventricular, but not kidney or brain lactate was negatively correlated with rScO2 and rSrO2. There was no correlation between CO or BP and rScO2 or rSrO2. CONCLUSIONS: Despite satisfactory CO and BP vital organ oxygenation can be poor. Tissue oxygen saturation, pH, and lactate, as measures of anaerobic metabolism, may reflect vital organ oxygenation and outcome.
Assuntos
Asfixia Neonatal/terapia , Encéfalo/metabolismo , Reanimação Cardiopulmonar , Rim/metabolismo , Consumo de Oxigênio , Oxigênio/metabolismo , Espectroscopia de Luz Próxima ao Infravermelho , Animais , Animais Recém-Nascidos , Asfixia Neonatal/metabolismo , Asfixia Neonatal/fisiopatologia , Pressão Sanguínea , Débito Cardíaco , Modelos Animais de Doenças , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Sus scrofa , Fatores de TempoRESUMO
The first milk, colostrum, is an important source of nutrients and an exclusive source of immunoglobulins (Ig), essential for the growth and protection from infection of newborn pigs. Colostrum intake has also been shown to affect the vitality and behaviour of neonatal pigs. The objective of this study was to evaluate the effects of feeding colostrum and plasma immunoglobulin on brain development in neonatal pigs. Positive correlations were found between growth, levels of total protein and IgG in blood plasma and hippocampus development in sow-reared piglets during the first 3 postnatal days. In piglets fed an elemental diet (ED) for 24h, a reduced body weight, a lower plasma protein level and a decreased level of astrocyte specific protein in the hippocampus was observed, as compared to those that were sow-reared. The latter was coincident with a reduced microgliogenesis and an essentially diminished number of neurons in the CA1 area of the hippocampus after 72h. Supplementation of the ED with purified plasma Ig, improved the gliogenesis and supported the trophic and immune status of the hippocampus. The data obtained indicate that the development of the hippocampus structure is improved by colostrum or an Ig-supplemented elemental diet in order to stimulate brain protein synthesis and its development during the early postnatal period.