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1.
Artigo em Inglês | MEDLINE | ID: mdl-38642731

RESUMO

Current treatments for schizophrenia (SCZ) remain largely ineffective in one-third of patients. Recent studies using stem cell therapy show a close relationship between stem cell immunomodulatory function and neuroinflammation in SCZ. To better investigate the efficacy of stem cell therapy for SCZ, human umbilical cord blood mesenchymal stem cells (hUC-MSC) with powerful immunomodulatory effects were administered to rats via the tail vein (once a week for 5 consecutive weeks starting from the weaning period) using a maternal immune activation (MIA) rodent model. Open field, PPI, Western blotting, Q-PCR, and immunofluorescence were used to assess the biological effects of repeated tail vein injections of hUC-MSC in offspring rats following the MIA model of SCZ. The results indicated that offspring of MIA rats exhibited schizophrenia-like (SCZ-like) anxiety behavior, with observed microglial activation triggering neuroinflammation. Furthermore, levels of IBA1, HMGB1, and PSD95 were significantly up-regulated, while SYP was significantly down-regulated. It is suggested that hUCB-MSCs may act through HMGB1, Iba1, PSD95, and related pathway molecules to alleviate neuroinflammation and repair synaptic damage by regulating the activity state of microglia. Consequently, this could improve the abnormal behavior observed in MIA offspring rats.

2.
Org Lett ; 26(15): 3014-3019, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38547326

RESUMO

The radical relay provides an effective paradigm for intermolecular assembly to achieve functionalization across remote chemical bonds. Herein, we report the first radical relay 1,3-carbocarbonylation of α-carbonyl alkyl bromides across two separate C═C bonds. The reaction is highly chemo- and regioselective, with two C(sp3)-C(sp3) bonds and one C═O bond formed in a single orchestrated operation. In addition, the synthesis method under mild conditions and using inexpensive copper as the catalyst allows facile access to structurally diverse 1,3-carbocarbonylation products. The plausible mechanism is investigated through a series of control experiments, including radical trapping, radical clock experiments, critical intermediate trapping, and 18O labeling experiment.

3.
J Chem Inf Model ; 64(7): 2290-2301, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38127053

RESUMO

Aptamers are single-stranded DNA or RNA oligos that can bind to a variety of targets with high specificity and selectivity and thus are widely used in the field of biosensing and disease therapies. Aptamers are generated by SELEX, which is a time-consuming procedure. In this study, using in silico and computational tools, we attempt to predict whether an aptamer can interact with a specific protein target. We present multiple data representations of protein and aptamer pairs and multiple machine-learning-based models to predict aptamer-protein interactions with a fair degree of selectivity. One of our models showed 96.5% accuracy and 97% precision, which are significantly better than those of the previously reported models. Additionally, we used molecular docking and SPR binding assays for two aptamers and the predicted targets as examples to exhibit the robustness of the APIPred algorithm. This reported model can be used for the high throughput screening of aptamer-protein pairs for targeting cancer and rapidly evolving viral epidemics.


Assuntos
Aptâmeros de Nucleotídeos , Simulação de Acoplamento Molecular , Aptâmeros de Nucleotídeos/química , Técnica de Seleção de Aptâmeros/métodos
4.
J Am Chem Soc ; 146(1): 742-751, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38112524

RESUMO

Covalent organic frameworks (COFs) are usually synthesized under solvothermal conditions that require the use of toxic organic solvents, high reaction temperatures, and complicated procedures. Additionally, their insolubility and infusibility present substantial challenges in the processing of COFs. Herein, we report a facile, green approach for the synthesis of imine-linked COFs in an aqueous solution at room temperature. The key behind the synthesis is the regulation of the reaction rate. The preactivation of aldehyde monomers using acetic acid significantly enhances their reactivity in aqueous solutions. Meanwhile, the still somewhat lower imine formation rate and higher imine breaking rates in aqueous solution, in contrast to conventional solvothermal synthesis, allow for the modulation of the reaction equilibrium and the crystallization of the products. As a result, highly crystalline COFs with large surface areas can be formed in relatively high yields in a few minutes. In total, 16 COFs are successfully synthesized from monomers with different molecular sizes, geometries, pendant groups, and core structures, demonstrating the versatility of this approach. Notably, this method works well on the gram scale synthesis of COFs. Furthermore, the aqueous synthesis facilitates the interfacial growth of COF nanolayers on the surface of cellulose nanofibers (CNFs). The resulting CNF@COF hybrid nanofibers can be easily processed into freestanding nanopapers, demonstrating high efficiency in removing trace amounts of antibiotics from wastewater. This study provides a route to the green synthesis and processing of various COFs, paving the way for practical applications in diverse fields.

5.
J Thorac Dis ; 15(4): 2068-2078, 2023 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-37197499

RESUMO

Background: Ventilator-associated pneumonia is a common complication of traumatic brain injury (TBI) patients, causing great harm to the life, health and society of patients. It is important to understand the risk factors related to ventilator-associated pneumonia for infection monitoring and control of patients. However, there are still some controversies about the risk factors in previous studies. Therefore, the purpose of this study was to explore the incidence and risk factors of ventilator-associated pneumonia in patients with TBI. Methods: Two independent researchers selected literature collected by systematically searching databases including PubMed, Ovid, Embase, and ScienceDirect using medical subject headings. The primary end points of the included literature were extracted, and the Cochrane Q test and I2 statistic were used to evaluate the heterogeneity between studies. The random effects model based on the restricted maximum likelihood method and the fixed effects model based on the reverse variance method were used to calculate and combine the relative risk or mean difference of relevant indicators. The publication bias was evaluated with the funnel plot and Egger test. All results were considered statistically significant at P<0.05. Results: A total of 11 articles were included in this study for meta-analysis, and a total of 2,301 patients with TBI were included. The incidence of ventilator-associated pneumonia in TBI patients was approximately 42% (95% CI: 32-53%). Tracheotomy significantly increased the risk of ventilator-associated pneumonia in patients with TBI [relative risk (RR) =3.71; 95% CI: 1.48-6.94; P<0.05]; the use of prophylactic antibiotics could significantly reduce the risk of ventilator-associated pneumonia in patients with TBI. The risk of pneumonia (RR =0.53; 95% CI: 0.18-0.88; P<0.05); compared with female patients, male patients with TBI had a significantly higher risk (about 46%) of ventilator-associated pneumonia (RR =1.46; 95% CI: 1.13-1.79; P<0.05). Conclusions: The risk of ventilator-associated pneumonia in patients with TBI is about 42%. Posttracheotomy and mechanical ventilation are risk factors for ventilator-associated pneumonia, while prophylactic use of antibiotics is a protective factor in the development of ventilator-associated pneumonia.

6.
Arch Microbiol ; 205(5): 168, 2023 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-37017772

RESUMO

Despite the successful application of toxins from Bacillus thuringiensis as biological control agents against pests, pests are showing resistance against an increasing number of Bacillus thuringiensis toxins due to evolution; thus, new toxins with higher toxicity and broad-spectrum activity against insects are being increasingly identified. To find new toxins, whole genome sequencing of the novel B. thuringiensis strain Bt S3076-1 was performed, and ten predicted toxic genes were identified in this study, including six cry genes, two tpp genes, one cyt gene and one vip gene, among which six were novel toxins. Subsequently, SDS‒PAGE analysis showed that the major proteins at the spore maturation stage were approximately 120 kDa, 70 kDa, 67 kDa, 60 kDa and 40 kDa, while active proteins after trypsin digestion (approximately 70 kDa and 40 kDa) exhibited LC50 values of 149.64 µg/g and 441.47 µg/g against Spodoptera frugiperda and Helicoverpa armigera larvae, respectively. Furthermore, pathological observation results showed that the peritrophic membrane of Spodoptera frugiperda and Helicoverpa armigera larvae was degraded. These findings will provide an experimental reference for further research on the insecticidal activity, toxicity spectrum and synergism of these toxins in Bt S3076-1.


Assuntos
Bacillus thuringiensis , Mariposas , Animais , Spodoptera/metabolismo , Bacillus thuringiensis/genética , Endotoxinas/genética , Proteínas de Bactérias/genética , Proteínas Hemolisinas/genética , Larva , Controle Biológico de Vetores
7.
Front Microbiol ; 13: 793122, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35547144

RESUMO

The highly effective phosphate-solubilizing microorganisms are significant for making full use of the potential phosphorus resources in the soil and alleviating the shortage of phosphorus resources. In this study, a phosphate-solubilizing fungus was isolated from wheat and cotton rhizosphere soils in the lower reaches of the Yellow River in China and was identified as Penicillium oxalicum by morphological and ITS sequencing analysis. In order to obtain a fungus with more efficient phosphorus solubilization ability, we tested three positive mutant strains (P1, P2, and P3) and three negative mutant strains (N1, N2, and N3) through low-energy nitrogen ion implantation mutagenesis. Compared with the parental strain, the phosphate-solubilizing capacity of P1, P2, and P3 was enhanced by 56.88%, 42.26%, and 32.15%, respectively, and that of N1, N2, and N3 was weakened by 47.53%, 35.27%, and 30.86%, respectively. Compared with the parental strain, the total amount of organic acids secreted significantly increased in the three positive mutant strains and decreased in the negative mutant strains; the pH of culture medium was significantly lower in the positive mutant strains and higher in the negative mutant strains. The capacity of phosphate-solubilizing fungus to secrete organic acids and reduce the growth-medium pH was closely related to its phosphate-solubilizing ability. The changes in the amount of organic acids secreted by mutants can alter their acidification and phosphate-solubilizing capacity. In conclusion, this study offers a theoretical basis and strain materials for the exploration and application of phosphate-solubilizing fungi.

8.
Ying Yong Sheng Tai Xue Bao ; 32(12): 4429-4438, 2021 Dec.
Artigo em Chinês | MEDLINE | ID: mdl-34951284

RESUMO

The high-efficiency phosphate solubilizing mutants of Penicillium oxalicum YTY were screened by mutagenesis of ion beam combined with UV. We analyzed the changes and correlation of phosphate solubilizing ability, pH, and organic acid for YTY and its mutants, and examined the phosphate solubilizing mechanism of P. oxalicum YTY. The results showed that five high-efficiency mutants, P9-8, P9-9, P15-4, P15-6, and P15-7 were screened, and that the phosphate solubili-zing ability of mutants was increased by more than 60% compared with YTY. In the process of pho-sphorus solubilization, both phosphorus solubilizing ability and rate of mutants were higher than that of YTY, and the mutants pH was significantly lower than YTY. The type and content of organic acids secreted by the mutants showed some variations. All mutants and YTY could secrete lactic acid, acetic acid and oxalic acid, while P9-8 also produced citric acid. The pH and the phosphate solubilizing ability of YTY and its mutants had a significant negative correlation. Phosphate solubilizing ability with organic acid and pH were all significantly correlated for YTY and the mutants, except P15-4. Organic acids and low environmental pH reduced by organic acids were the probable mechanism for P. oxalicum to dissolve phosphorus. Radiation of ion beam combined with UV could change the type and content of organic acids of P. oxalicum YTY, and initiate other H+ releasing pathways to lower pH, and participate phosphorus dissolution. The study provided biological mate-rials and theoretical basis for the research and development of high-efficiency phosphate solubilizing P. oxalicum and understanding the phosphate solubilizing mechanism of P. oxalicum.


Assuntos
Penicillium , Fosfatos , Concentração de Íons de Hidrogênio , Penicillium/genética , Fósforo
9.
Curr Stem Cell Res Ther ; 16(8): 949-957, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33563178

RESUMO

Bone regeneration is a critical problem in modern clinical practice. Osteocytes are the most abundant cell population of mature adult bone that play a major role in the regulation of bone formation. In humans, segmental bone defects cannot be repaired by endogenous regenerative mechanisms. Bone tissue engineering (BTE) is a promising option for the treatment of difficult segmental and skeletal defects. BTE requires suitable cell sources with rapid expansion and adequate function, inducible factors, and scaffolds to successfully regenerate or repair the bone injury. To overcome the disadvantages of using allogeneic and autologous tissue grafts, stem cell-based therapy has progressed in regenerative medicine. In the past few decades, numerous attempts have been made to generate osteocytes by using pluripotent stem cells (PSCs) to repair and regenerate bone defects. Human induced pluripotent stem cells (hiPSCs) are PSCs that can self-renew and differentiate into a variety of cell types. Reprogramming of human somatic cells into hiPSCs provides a new opportunity for regenerative medicine, cell-based drug discovery, disease modeling, and toxicity assessment. The ability to differentiate hiPSCs from mesenchymal stem cells (iPSC-MSCs) is essential for treating bone-related damages and injuries. Several in vitro studies revealed that the cell origin of iPSCs, a combination of transcription factors, the type of promoter in the vector, transduction methods, scaffolds, differentiating techniques, and culture medium, may affect the osteogenic differentiation potential of hiPSCs. This review will focus on several factors that influence the osteogenic differentiation of human iPSCs.


Assuntos
Diferenciação Celular , Células-Tronco Pluripotentes Induzidas , Osteogênese , Osso e Ossos/citologia , Humanos , Células-Tronco Pluripotentes Induzidas/citologia
10.
J Invertebr Pathol ; 173: 107386, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32325072

RESUMO

Bacillus thuringiensis (Bt) can synthesize insecticides to efficiently control insects. In this study, Bt strain S3580-1 with mosquitocidal activity was subjected to whole genome sequencing using an Illumina HiSeq 2000 system. A novel toxin, Cry80Aa1, was identified based on the resulting data. A conserved domain analysis revealed that Cry80Aa1 includes the Ricin_B_lectin domain (located at 10-150) and the Toxin_10 domain (located at 155-353). Phylogenetic tree analysis showed that Cry80Aa1 was in a distinct clade significantly distinguished from the known Cry proteins containing the Toxin_10 domain. Bioassays demonstrated that the Cry80Aa1 protein exhibited toxicity to third instar larvae of Culex pipiens pallens (LC50: 71.9 µg/mL; 95% FL: 59.5-122.7 µg/mL).


Assuntos
Toxinas de Bacillus thuringiensis , Culex , Endotoxinas , Proteínas Hemolisinas , Inseticidas , Controle de Mosquitos , Controle Biológico de Vetores , Animais , Culex/crescimento & desenvolvimento , Larva/crescimento & desenvolvimento
11.
Braz J Microbiol ; 51(2): 437-445, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32036551

RESUMO

As a pathogenic bacterium, Bacillus thuringiensis (Bt) has become an alternative to chemical insecticides in commercial agricultural to control forestry pests and mosquitoes. To prevent pest resistance, many novel Bt strains have been isolated. Strain S3580-1 (WGS: VHPX0000000) used in this research and originally isolated from Hainan Qixianling National Forest Park (China) showed significant toxicity to Culex pipiens pallens. Here, using whole genome sequencing, assembly, and bioinformatics analysis, the predicted S3580-1CG_5163 (GenBank Accession No. MK124137) gene-encoded protein was found to share low homology with known toxins designated by the Bt toxin nomenclature system. It was considered to be an ETX/MTX2-type toxin and was designated Epp. Bioinformatics analysis showed that the predicted S3580-1CG_5163 gene-encoded protein Epp shared low identity with other known toxic protein sequences containing Cry-ETX/MTX conserved domains at the amino acid level, but significant similarity at the structural level. In addition, bioassays showed that Epp was toxic against Spodoptera litura (LC50 296.133 µg/mL; 95% FL 200.555-471.318 µg/mL) and Cx. pipiens pallens (LC50 322.193 µg/mL; 95% FL 238.217-477.243 µg/mL). On pathological observation, the peritrophic membrane of Cx. pipiens pallens larvae was degraded causing the midgut structure to become incomplete, resulting in larval death. Further bioassays are required to fully elucidate the insecticidal spectrum of the ETX/MTX2-type toxin Epp, and thereby provide future research directions.


Assuntos
Toxinas de Bacillus thuringiensis/toxicidade , Bacillus thuringiensis/química , Culicidae , Larva , Animais , Toxinas de Bacillus thuringiensis/classificação , Bioensaio , China , Inseticidas , Controle Biológico de Vetores/métodos
12.
3 Biotech ; 8(7): 293, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29963353

RESUMO

Mosquitocidal Bacillus thuringiensis (Bt) strain S2160-1 was proposed to be an alternative to Bacillus thuringiensis subsp. israelensis (Bti). Discovering and validating a toxic gene by experimentation was a complex and time-consuming task, which can benefit from high-throughput sequencing analysis. In this research, we predicted and identified toxic proteins in the strain S2160-1 based on the draft whole genome sequence data. Through a local BLASP, 46 putative toxins were identified in S2160-1 genome, by searching against a customized B. thuringiensis toxin proteins database containing 653 protein or peptide sequences retrieved from public accessible resources and PCR/clone results in our laboratory (e value = 1e - 5). These putative toxins consist of 42 to 1216 amino acids. The molecular weights are ranged from 4.86 to 137.28 kDa. The isoelectric point of these candidate toxins varied from 4.3 to 10.06, and 16 out of which had a pH greater than 7.0. The analysis of tertiary structure and PFAM domain showed that 12 potential plasmid toxins may share higher similarity (9/12 QMEAN4 score > 0.3) with known Bt toxins. In addition, functional annotation indicated that these 12 potential toxins were involved in "sporulation resulting in formation of a cellular spore" and "toxin activity". Moreover, multiple alignment and phylogenetic analysis were carried out to elucidate the evolutionary relationship among 101 known crystal or toxin proteins from public database and them with MEGA 6.0. It indicated that PS2160P2_1 and PS2160P2_153 may be potential Cry4-like toxins in Bt S2160-1. This research may lay the foundation for future functional analysis of Bt S2160-1 toxin proteins to reveal their biological roles.

13.
World J Microbiol Biotechnol ; 30(12): 3273-7, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25256415

RESUMO

The Bacillus thuringiensis strain S2160-1 has previously been identified as being highly toxic to mosquito larvae and a viable alternative to strains currently used commercially to control these insects. A PCR approach had identified the presence of four putative insecticidal toxin genes (cry30Ea, cry30 Ga, cry50Ba and cry54Ba) in this strain, but did not identify the genes that encoding three of the main crystal toxin proteins of size 140 and 130 and 30 kDa. In this study we used mass spectrometry to identify the 130 kDa toxin as a rare Cry4 toxin (Cry4Cb3). The gene encoding this toxin was cloned and expressed and the toxin shown to have mosquitocidal activity against Culex quinquefasciatus.


Assuntos
Bacillus thuringiensis/química , Toxinas Bacterianas/análise , Inseticidas/análise , Animais , Toxinas Bacterianas/química , Bioensaio , Culex/efeitos dos fármacos , Inseticidas/química , Larva/efeitos dos fármacos , Lepidópteros/efeitos dos fármacos , Espectrometria de Massas , Peso Molecular , Análise de Sobrevida
14.
Clin Cancer Res ; 20(9): 2457-65, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24634374

RESUMO

PURPOSE: It has been demonstrated that large numbers of tumor-specific T cells for adoptive cell transfer (ACT) can be manufactured by retroviral genetic engineering of autologous peripheral blood lymphocytes and expanding them over several weeks. In mouse models, this therapy is optimized when administered with dendritic cell (DC) vaccination. We developed a short 1-week manufacture protocol to determine the feasibility, safety, and antitumor efficacy of this double cell therapy. EXPERIMENTAL DESIGN: A clinical trial (NCT00910650) adoptively transferring MART-1 T-cell receptor (TCR) transgenic lymphocytes together with MART-1 peptide-pulsed DC vaccination in HLA-A2.1 patients with metastatic melanoma. Autologous TCR transgenic cells were manufactured in 6 to 7 days using retroviral vector gene transfer, and reinfused with (n = 10) or without (n = 3) prior cryopreservation. RESULTS: A total of 14 patients with metastatic melanoma were enrolled and 9 of 13 treated patients (69%) showed evidence of tumor regression. Peripheral blood reconstitution with MART-1-specific T cells peaked within 2 weeks of ACT, indicating rapid in vivo expansion. Administration of freshly manufactured TCR transgenic T cells resulted in a higher persistence of MART-1-specific T cells in the blood as compared with cryopreserved. Evidence that DC vaccination could cause further in vivo expansion was only observed with ACT using noncryopreserved T cells. CONCLUSION: Double cell therapy with ACT of TCR-engineered T cells with a very short ex vivo manipulation and DC vaccines is feasible and results in antitumor activity, but improvements are needed to maintain tumor responses.


Assuntos
Vacinas Anticâncer/imunologia , Células Dendríticas/imunologia , Imunoterapia Adotiva , Antígeno MART-1/genética , Melanoma/imunologia , Melanoma/terapia , Receptores de Antígenos de Linfócitos T/genética , Linfócitos T/imunologia , Adulto , Vacinas Anticâncer/administração & dosagem , Vacinas Anticâncer/efeitos adversos , Células Dendríticas/metabolismo , Feminino , Humanos , Imunoterapia Adotiva/efeitos adversos , Antígeno MART-1/imunologia , Masculino , Melanoma/diagnóstico , Melanoma/mortalidade , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/imunologia , Tomografia por Emissão de Pósitrons , Linfócitos T/metabolismo , Tomografia Computadorizada por Raios X , Transdução Genética , Resultado do Tratamento , Vacinação
15.
Cancer Discov ; 3(4): 418-29, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23519018

RESUMO

UNLABELLED: Adoptive cell transfer (ACT) of genetically engineered T cells expressing cancer-specific T-cell receptors (TCR) is a promising cancer treatment. Here, we investigate the in vivo functional activity and dynamics of the transferred cells by analyzing samples from 3 representative patients with melanoma enrolled in a clinical trial of ACT with TCR transgenic T cells targeted against the melanosomal antigen MART-1. The analyses included evaluating 19 secreted proteins from individual cells from phenotypically defined T-cell subpopulations, as well as the enumeration of T cells with TCR antigen specificity for 36 melanoma antigens. These analyses revealed the coordinated functional dynamics of the adoptively transferred, as well as endogenous, T cells, and the importance of highly functional T cells in dominating the antitumor immune response. This study highlights the need to develop approaches to maintaining antitumor T-cell functionality with the aim of increasing the long-term efficacy of TCR-engineered ACT immunotherapy. SIGNIFICANCE: A longitudinal functional study of adoptively transferred TCR­engineered lymphocytes yielded revealing snapshots for understanding the changes of antitumor responses over time in ACT immunotherapy of patients with advanced melanoma.


Assuntos
Imunoterapia Adotiva , Antígeno MART-1/imunologia , Melanoma/terapia , Neoplasias Cutâneas/terapia , Linfócitos T/imunologia , Adulto , Feminino , Humanos , Masculino , Melanoma/imunologia , Pessoa de Meia-Idade , Receptores de Antígenos de Linfócitos T/imunologia , Neoplasias Cutâneas/imunologia
16.
J Neurosci Res ; 89(3): 365-72, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-21259323

RESUMO

Mice that are deficient in classical major histocompatibility complex class I (MHCI) have abnormalities in synaptic plasticity and neurodevelopment and have more extensive loss of synapses and reduced axon regeneration after sciatic nerve transection, suggesting that MHCI participates in maintaining synapses and axon regeneration. Little is known about the biological consequences of up-regulating MHCI's expression on neurons. To understand MHCI's neurobiological activity better, and in particular its role in neurorepair after injury, we have studied neurorepair in a transgenic mouse model in which classical MHCI expression is up-regulated only on neurons. Using a well-established spinal cord injury (SCI) model, we observed that transgenic mice with elevated neuronal MHCI expression had significantly better recovery of locomotor abilities after SCI than wild-type mice. Although previous studies have implicated inflammation as both deleterious and beneficial for recovery after SCI, our results point directly to enhanced neuronal MHCI expression as a beneficial factor for promoting recovery of locomotor function after SCI.


Assuntos
Regulação da Expressão Gênica/genética , Antígenos de Histocompatibilidade Classe I/genética , Locomoção/fisiologia , Recuperação de Função Fisiológica/fisiologia , Traumatismos da Medula Espinal/fisiopatologia , Análise de Variância , Animais , Modelos Animais de Doenças , Teste de Esforço/métodos , Lateralidade Funcional , Locomoção/genética , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/metabolismo , Fosfopiruvato Hidratase/genética , Recuperação de Função Fisiológica/genética , Traumatismos da Medula Espinal/patologia
17.
Immunol Lett ; 135(1-2): 118-23, 2011 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-20974178

RESUMO

Studies of mice deficient in classical major histocompatability complex class I (MHCI) revealed that MHCI plays an important role in neurodevelopment in the central nervous system. We previously studied the effects of recombinant MHCI molecules on wildtype retina explants and observed that MHCI can inhibit retina neurite outgrowth, with self-MHCI molecules having greater inhibitory effect than non-self MHCI molecules. Here, we examined classical MHCI's effects on axon outgrowth from neurons of the peripheral nervous system (PNS). We used the embryonic dorsal root ganglia (DRG) explant model since their neurons express MHCI and because DRG explants have been widely used to assess the effects of molecules on axonal outgrowth from PNS neurons. We observed that picomolar levels of a recombinant self-MHCI molecule, but not non-self MHCI molecules, inhibited axon outgrowth from DRG explants. This differential sensitivity to self- vs. non-self MHCI suggests that early in development, self-MHCI may "educate" PNS neurons to express appropriate MHCI receptors, as occurs during natural killer cell development. Furthermore, we observed that a MHCI tetramer stained embryonic DRG neurons, indicating the expression of classical MHCI receptors. These results suggest that MHCI and MHCI receptors play roles during early stages of PNS development and may provide new targets of therapeutic strategies to promote neuronal outgrowth after PNS injury.


Assuntos
Gânglios Espinais/imunologia , Regulação da Expressão Gênica/imunologia , Antígenos de Histocompatibilidade Classe I/imunologia , Neuritos/imunologia , Traumatismos dos Nervos Periféricos , Nervos Periféricos/imunologia , Animais , Axônios/imunologia , Axônios/metabolismo , Embrião de Mamíferos/imunologia , Embrião de Mamíferos/metabolismo , Gânglios Espinais/metabolismo , Antígenos de Histocompatibilidade Classe I/biossíntese , Camundongos , Neuritos/metabolismo , Nervos Periféricos/metabolismo
18.
J Neuroimmunol ; 232(1-2): 8-16, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20950866

RESUMO

Mice deficient in classical major histocompatibility complex class I (MHCI) have aberrations in neurodevelopment. The consequences of upregulated neuronal MHCI expression have not been examined. We found that transgenic C57Bl/6 mice that are engineered to express higher levels of self-D(b) on their CNS neurons have alterations in their hippocampal morphology and retinogeniculate projections, as well as impaired neurorepair responses. Thus, enhanced neuronal classical MHCI expression can lead to aberrations in neural circuitry and neurorepair. These findings complement a growing body of knowledge concerning the neurobiological activities of MHCI and may have potential clinical relevance.


Assuntos
Antígenos de Histocompatibilidade Classe I/metabolismo , Regeneração Nervosa/fisiologia , Neurogênese/fisiologia , Neurônios/metabolismo , Acetilcolinesterase/metabolismo , Animais , Potenciais Pós-Sinápticos Excitadores/fisiologia , Hipocampo/imunologia , Hipocampo/metabolismo , Hipocampo/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Neurônios/imunologia , Neurônios/patologia , Técnicas de Cultura de Órgãos , Transmissão Sináptica/fisiologia
19.
J Immunol ; 184(2): 816-23, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20018625

RESUMO

Studies of mice lacking MHC class I (MHC I)-associated proteins have demonstrated a role for MHC I in neurodevelopment. A central question arising from these observations is whether neuronal recognition of MHC I has specificity for the MHC I allele product and the peptide presented. Using a well-established embryonic retina explant system, we observed that picomolar levels of a recombinant self-MHC I molecule inhibited neurite outgrowth. We then assessed the neurobiological activity of a panel of recombinant soluble MHC Is, consisting of different MHC I heavy chains with a defined self- or nonself-peptide presented, on cultured embryonic retinas from mice with different MHC I haplotypes. We observed that self-MHC I allele products had greater inhibitory neuroactivity than nonself-MHC I molecules, regardless of the nature of the peptide presented, a pattern akin to MHC I recognition by some innate immune system receptors. However, self-MHC I molecules had no effect on retinas from MHC I-deficient mice. These observations suggest that neuronal recognition of MHC I may be coordinated with the inherited MHC I alleles, as occurs in the innate immune system. Consistent with this notion, we show that MHC I and MHC I receptors are coexpressed by precursor cells at the earliest stages of retina development, which could enable such coordination.


Assuntos
Alelos , Apresentação de Antígeno , Antígenos de Histocompatibilidade Classe I/genética , Neurônios/imunologia , Peptídeos/imunologia , Animais , Autoantígenos/imunologia , Células-Tronco Embrionárias , Imunidade Inata , Camundongos , Neuritos/imunologia , Neurônios/citologia , Retina/embriologia
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