共查询到20条相似文献,搜索用时 46 毫秒
1.
Background
Administration of recombinant G-CSF following cytoreductive therapy enhances the recovery of myeloid cells, minimizing the risk of opportunistic infection. Free G-CSF, however, is expensive, exhibits a short half-life, and has poor biological activity in vivo.Methods
We evaluated whether the biological activity of G-CSF could be improved by pre-association with anti-G-CSF mAb prior to injection into mice.Results
We find that the efficacy of G-CSF therapy can be enhanced more than 100-fold by pre-association of G-CSF with an anti-G-CSF monoclonal antibody (mAb). Compared with G-CSF alone, administration of G-CSF/anti-G-CSF mAb complexes induced the potent expansion of CD11b+Gr-1+ myeloid cells in mice with or without concomitant cytoreductive treatment including radiation or chemotherapy. Despite driving the dramatic expansion of myeloid cells, in vivo antigen-specific CD8+ T cell immune responses were not compromised. Furthermore, injection of G-CSF/anti-G-CSF mAb complexes heightened protective immunity to bacterial infection. As a measure of clinical value, we also found that antibody complexes improved G-CSF biological activity much more significantly than pegylation.Conclusions
Our findings provide the first evidence that antibody cytokine complexes can effectively expand myeloid cells, and furthermore, that G-CSF/anti-G-CSF mAb complexes may provide an improved method for the administration of recombinant G-CSF.2.
Mengjuan Liu Jiaqi Wang Hongping Tang Li Fan Liang Zhao Hai-Bin Wang Yan Zhou Wen-Song Tan 《Biotechnology letters》2018,40(11-12):1487-1493
Objective
To explore the impact of taurine on monoclonal antibody (mAb) basic charge variants in Chinese hamster ovary (CHO) cell culture.Results
In fed-batch culture, adding taurine in the feed medium slightly increased the maximum viable cell density and mAb titers in CHO cells. What’s more, taurine significantly decreased the lysine variant and oxidized variant levels, which further decreased basic variant contents from 32 to 27%. The lysine variant content in the taurine culture was approximately 4% lower than that in control condition, which was the main reason for the decrease in basic variants. Real-time PCR and cell-free assay revealed that taurine played a critical role in the upregulation of relative basic carboxypeptidase and stimulating extracellular basic carboxypeptidase activities.Conclusion
Taurine exhibits noticeable impact on lower basic charge variants, which are mainly due to the decrease of lysine variant and oxidized protein variants.3.
Larissa Lumi Watanabe Ishikawa Thaís Graziela Donegá França Fernanda Chiuso-Minicucci Sofia Fernanda Gonçalves Zorzella-Pezavento Nelson Mendes Marra Paulo Câmara Marques Pereira Célio Lopes Silva Alexandrina Sartori 《Genetic vaccines and therapy》2009,7(1):11
Background
Protein-calorie malnutrition (PCM) is the most common type of malnutrition. PCM leads to immunodeficiency and consequent increased susceptibility to infectious agents. In addition, responses to prophylactic vaccines depend on nutritional status. This study aims to evaluate the ability of undernourished mice to mount an immune response to a genetic vaccine (pVAXhsp65) against tuberculosis, containing the gene coding for the heat shock protein 65 from mycobacteria.Methods
Young adult female BALB/c mice were fed ad libitum or with 80% of the amount of food consumed by a normal diet group. We initially characterized a mice model of dietary restriction by determining body and spleen weights, hematological parameters and histopathological changes in lymphoid organs. The ability of splenic cells to produce IFN-gamma and IL-4 upon in vitro stimulation with LPS or S. aureus and the serum titer of specific IgG1 and IgG2a anti-hsp65 antibodies after intramuscular immunization with pVAXhsp65 was then tested.Results
Dietary restriction significantly decreased body and spleen weights and also the total lymphocyte count in blood. This restriction also determined a striking atrophy in lymphoid organs as spleen, thymus and lymphoid tissue associated with the small intestine. Specific antibodies were not detected in mice submitted to dietary restriction whereas the well nourished animals produced significant levels of both, IgG1 and IgG2a anti-hsp65.Conclusion
20% restriction in food intake deeply compromised humoral immunity induced by a genetic vaccine, alerting, therefore, for the relevance of the nutritional condition in vaccination programs based on these kinds of constructs.4.
5.
Chen Wang Jiaqi Wang Min Chen Li Fan Liang Zhao Wen-Song Tan 《Biotechnology letters》2018,40(8):1201-1208
Objective
To explore the influence of ultra-low carbon dioxide partial pressure (pCO2) on the monoclonal antibody (mAb) N-glycosylation profile in Chinese hamster ovary (CHO) cell culture.Results
In fed-batch bioreactor cultures, lowering the pCO2 in the medium (<?25 mmHg) via increasing headspace aeration decreased the cell viability and mAb production in CHO cells. Additionally, mAb galactosylation under low pCO2 was approximately 27.45?±?2.13%, noticeably higher than that observed under normal pCO2 (21.36?±?1.66%) at harvest. However, all of the relevant intracellular nucleotide sugar concentrations were dramatically decreased to approximately 50% of the levels found under normal pCO2 on day 7. Real-time PCR revealed that the upregulation of galactosylation-related glycosyltransferase genes and substrate transporter genes played a critical role in the improved galactosylation under the ultra-low pCO2 condition.Conclusions
In the bioreactor culture processes, ultra-low pCO2 demonstrated a positive effect on mAb galactosylation.6.
Rachel A. Spicer Christoph Steinbeck 《Metabolomics : Official journal of the Metabolomic Society》2018,14(1):16
Introduction
Data sharing is being increasingly required by journals and has been heralded as a solution to the ‘replication crisis’.Objectives
(i) Review data sharing policies of journals publishing the most metabolomics papers associated with open data and (ii) compare these journals’ policies to those that publish the most metabolomics papers.Methods
A PubMed search was used to identify metabolomics papers. Metabolomics data repositories were manually searched for linked publications.Results
Journals that support data sharing are not necessarily those with the most papers associated to open metabolomics data.Conclusion
Further efforts are required to improve data sharing in metabolomics.7.
Background
The present study elucidates the protective potential of bromelain against dichlorvos intoxication in mice brains. Dichlorvos induces the oxidative stress by disproportionating the balance between free radicals generation and their scavenging in neurons which leads to neuronal degeneration.Methods
In this study, mice were divided into four groups-group I (control), group II (dichlorvos treated), group III (bromelain treated) and group IV (exposed to both bromelain and dichlorvos both).Results
Dichlorvos treatment increased the levels of thiobarbituric acid reactive substances (TBARS) and protein carbonyl content (PCC) which indicate the increased oxidative stress. Meanwhile, brain endogenous antioxidants and cholinesterases level was decreased after dichlorvos exposure. Levels of TBARS and PCC decreased whereas cholinesterases level was recorded to be elevated after bromelain exposure.Conclusion
Bromelain offered neuroprotection by decreasing oxidative stress and augmenting cholinesterases in mice brains. This study highlights the invulnerability of bromelain against oxidative and cholinergic deficits in mice brains.8.
Benjamin H Natelson Roxann Intriligator Neil S Cherniack Helena K Chandler Julian M Stewart 《Dynamic medicine : DM》2007,6(1):2
Context
Patients with chronic fatigue syndrome and those with orthostatic intolerance share many symptoms, yet questions exist as to whether CFS patients have physiological evidence of orthostatic intolerance.Objective
To determine if some CFS patients have increased rates of orthostatic hypotension, hypertension, tachycardia, or hypocapnia relative to age-matched controls.Design
Assess blood pressure, heart rate, respiratory rate, end tidal CO2 and visual analog scales for orthostatic symptoms when supine and when standing for 8 minutes without moving legs.Setting
Referral practice and research center.Participants
60 women and 15 men with CFS and 36 women and 4 men serving as age matched controls with analyses confined to 62 patients and 35 controls showing either normal orthostatic testing or a physiological abnormal test.Main outcome measures
Orthostatic tachycardia; orthostatic hypotension; orthostatic hypertension; orthostatic hypocapnia or combinations thereof.Results
CFS patients had higher rates of abnormal tests than controls (53% vs 20%, p < .002), but rates of orthostatic tachycardia, orthostatic hypotension, and orthostatic hypertension did not differ significantly between patients and controls (11.3% vs 5.7%, 6.5% vs 2.9%, 19.4% vs 11.4%, respectively). In contrast, rates of orthostatic hypocapnia were significantly higher in CFS than in controls (20.6% vs 2.9%, p < .02). This CFS group reported significantly more feelings of illness and shortness of breath than either controls or CFS patients with normal physiological tests.Conclusion
A substantial number of CFS patients have orthostatic intolerance in the form of orthostatic hypocapnia. This allows subgrouping of patients with CFS and thus reduces patient pool heterogeneity engendered by use of a clinical case definition.9.
Background
Disruption to the blood brain barrier (BBB) is a leading factor associated with the development of postoperative cognitive dysfunction (POCD). Despite this, the underlying mechanism by which BBB disruption promotes POCD in the elderly population has not yet been not fully elucidated.Results
In this study, we established a POCD mice model using isoflurane, and observed the highly expressed occludin and claudin 5 in brain tissues concomitant with the increased enrichment of CD4 positive cells and NK cells in the hippocampus of POCD mice compared to normal and non-POCD control.Conclusions
Our data suggests that peripheral immune cells may participate in the inflammatory reaction within the hippocampus, following the administration of anesthesia via inhalation with the destruction of the blood-brain barrier.10.
N. Cesbron A.-L. Royer Y. Guitton A. Sydor B. Le Bizec G. Dervilly-Pinel 《Metabolomics : Official journal of the Metabolomic Society》2017,13(8):99
Introduction
Collecting feces is easy. It offers direct outcome to endogenous and microbial metabolites.Objectives
In a context of lack of consensus about fecal sample preparation, especially in animal species, we developed a robust protocol allowing untargeted LC-HRMS fingerprinting.Methods
The conditions of extraction (quantity, preparation, solvents, dilutions) were investigated in bovine feces.Results
A rapid and simple protocol involving feces extraction with methanol (1/3, M/V) followed by centrifugation and a step filtration (10 kDa) was developed.Conclusion
The workflow generated repeatable and informative fingerprints for robust metabolome characterization.11.
Lili Du Runxiao Lv Xiaoyi Yang Shaohang Cheng Jing Xu Tingxian Ma 《Biotechnology letters》2016,38(6):931-939
Objectives
To explore the effect of placenta-derived mesenchymal stem cells on scar formation as well as the underlying mechanism.Results
The isolated placenta-derived mesenchymal stem cells from mice were distributed in the wounded areas of scalded mouse models, attenuated inflammatory responses and decreased the deposition of collagens, thus performing a beneficial effect against scar formation. Hypoxia enhanced the protective effect of placenta-derived mesenchymal stem cells and hypoxia-inducible factor-1α was involved in the protective effect of placenta-derived mesenchymal stem cells in hypoxic condition.Conclusions
Hypoxia enhanced the protective effect of placenta-derived mesenchymal stem cells through hypoxia-inducible factor-1α and PMSCs may have a potential application in the treatment of wound.12.
Li Li Chang-Sheng Wu Guan-Mei Hou Ming-Zhe Dong Zhen-Bo Wang Yi Hou Heide Schatten Gui-Rong Zhang Qing-Yuan Sun 《Reproductive biology and endocrinology : RB&E》2018,16(1):110
Background
Diabetes induces many complications including reduced fertility and low oocyte quality, but whether it causes increased mtDNA mutations is unknown.Methods
We generated a T2D mouse model by using high-fat-diet (HFD) and Streptozotocin (STZ) injection. We examined mtDNA mutations in oocytes of diabetic mice by high-throughput sequencing techniques.Results
T2D mice showed glucose intolerance, insulin resistance, low fecundity compared to the control group. T2D oocytes showed increased mtDNA mutation sites and mutation numbers compared to the control counterparts. mtDNA mutation examination in F1 mice showed that the mitochondrial bottleneck could eliminate mtDNA mutations.Conclusions
T2D mice have increased mtDNA mutation sites and mtDNA mutation numbers in oocytes compared to the counterparts, while these adverse effects can be eliminated by the bottleneck effect in their offspring. This is the first study using a small number of oocytes to examine mtDNA mutations in diabetic mothers and offspring.13.
Background
There is an urgent need to develop new innovative therapies for the control of advanced cancer. The combination of antigen-specific immunotherapy with the employment of immunomodulatory agents has emerged as a potentially plausible approach for the control of advanced cancer.Methods
In the current study, we explored the combination of the DNA vaccine encoding calreticulin (CRT) linked to human papillomavirus type 16 (HPV-16) E7 antigen (CRT/E7) with the TLR7 agonist imiquimod for their ability to generate E7-specific immune responses and antitumor effects in tumor-bearing mice.Results
We observed that treatment with CRT/E7 DNA in combination with imiquimod leads to an enhancement in the E7-specific CD8+ T cell immune responses and a decrease in the number of myeloid-derived suppressor cells in the tumor microenvironment of tumor-bearing mice. Furthermore, treatment with CRT/E7 DNA in combination with imiquimod leads to significantly improved antitumor effects and prolonged survival in treated mice. In addition, treatment with imiquimod led to increased number of NK1.1+ cells and F4/80+ cells in the tumor microenvironment. Macrophages and NK1.1+ cells were found to play an important role in the antitumor effects mediated by treatment with CRT/E7 DNA in combination with imiquimod.Conclusions
Thus, our data suggests that the combination of therapeutic HPV DNA vaccination with topical treatment with the TLR7 agonist imiquimod enhances the antitumor immunity induced by DNA vaccination. The current study has significant implications for future clinical translation.14.
Objectives
Interleukin- 1 (IL-1) is a multifunctional proinflammatory cytokine. There have been studies suggesting a role in affecting growth and invasiveness of malignant breast cells by either blocking or stimulating growth of cultured MCF-7 breast cancer cells. This effect may be mediated by induction of COX-2. Aspirin is an inhibitor of COX-2 and has been implicated, with other non-steroidal anti-inflammatory drugs (NSAIDS) in prevention and treatment of breast cancer. In this study the in vitro effects of IL-1 and aspirin on growth of MCF-7 human breast cancer cells was examined.Methods
MCF-7 cells were treated with various concentrations of IL-1 and aspirin alone and in combination. Cell growth was assessed by cell number measurement.Results
Aspirin significantly decreased growth rate in a dose-dependant manner, alone and as a combined treatment with IL-1 with a maximum reduction in growth rate at 300 mg/ml (P < 0.05). Treatment with IL-1 alone showed no significant effect on growth rate of MCF-7 cells (P > 0.05).Conclusion
This study confirms that aspirin suppresses the proliferation rate of MCF-7 cells both as a single agent and in combination with IL-1. It also suggests that IL-1 alone does not stimulate or inhibit growth of MCF-7 cells.15.
Fabiany da Costa Gonçalves Mateus Grings Natália Schneider Nunes Fernanda Otesbelgue Pinto Tuane Nerissa Alves Garcez Fernanda Visioli Guilhian Leipnitz Ana Helena Paz 《Biotechnology letters》2017,39(4):613-622
Objective
To investigate the effects of oxidative stress injury in dextran sulfate sodium (DSS)-induced colitis in mice treated with mesenchymal stem cells (MSC).Results
Mice exposed to oral administration of 2% DSS over 7 days presented a high disease activity index and an intense colonic inflammation. Systemic infusion of MSC protected from severe colitis, reducing weight loss and diarrhea while lowering the infiltration of inflammatory cells. Moreover, toxic colitis injury increased oxidative stress. Administration of DSS decreased reduced glutathione (GSH) and superoxide dismutase (SOD) activity, and increased thiobarbituric acid-reactive substances levels in the colon. No alteration was found in catalase (CAT) and glutathione peroxidase (GPx) activity. Otherwise, MSC transplantation was able to prevent the decrease of GSH levels and SOD activity suggestive of an antioxidant property of MSC.Conclusion
The oxidative stress is a pathomechanism underlying the pathophysiology of colitis and MSC play an important role in preventing the impairment of antioxidants defenses in inflamed colon.16.
Joon-Geun Ha Young Seok Song Sunghwan Jung Soohwan Jang Yong-Kweon Kim Seoung Jai Bai Jae-Hyoung Park Seung-Ki Lee 《Biotechnology letters》2017,39(6):849-855
Objective
To fabricate a novel microbial photobioelectrochemical cell using silicon microfabrication techniques.Results
High-density photosynthetic cells were immobilized in a microfluidic chamber, and ultra-microelectrodes in a microtip array were inserted into the cytosolic space of the cells to directly harvest photosynthetic electrons. In this way, the microbial photobioelectrochemical cell operated without the aid of electron mediators. Both short circuit current and open circuit voltage of the microbial photobioelectrochemical cell responded to light stimuli, and recorded as high as 250 pA and 45 mV, respectively.Conclusion
A microbial photobioelectrochemical cell was fabricated with potential use in next-generation photosynthesis-based solar cells and sensors.17.
Daniel Cañueto Josep Gómez Reza M. Salek Xavier Correig Nicolau Cañellas 《Metabolomics : Official journal of the Metabolomic Society》2018,14(3):24
Introduction
Adoption of automatic profiling tools for 1H-NMR-based metabolomic studies still lags behind other approaches in the absence of the flexibility and interactivity necessary to adapt to the properties of study data sets of complex matrices.Objectives
To provide an open source tool that fully integrates these needs and enables the reproducibility of the profiling process.Methods
rDolphin incorporates novel techniques to optimize exploratory analysis, metabolite identification, and validation of profiling output quality.Results
The information and quality achieved in two public datasets of complex matrices are maximized.Conclusion
rDolphin is an open-source R package (http://github.com/danielcanueto/rDolphin) able to provide the best balance between accuracy, reproducibility and ease of use.18.
Dingcheng Gao Vivek Mittal Yi Ban Ana Rita Lourenco Shira Yomtoubian Sharrell Lee 《生物学前沿》2018,13(4):277-286
Background
Metastasis is the primary cause of mortality in cancer patients. Therefore, elucidating the genetics and epigenetics of metastatic tumor cells and the mechanisms by which tumor cells acquire metastatic properties constitute significant challenges in cancer research.Objective
To summarize the current understandings of the specific genotype and phenotype of the metastatic tumor cells.Method and Result
In-depth genetic analysis of tumor cells, especially with advances in the next-generation sequencing, have revealed insights of the genotypes of metastatic tumor cells. Also, studies have shown that the cancer stem cell (CSC) and epithelial to mesenchymal transition (EMT) phenotypes are associated with the metastatic cascade.Conclusion
In this review, we will discuss recent advances in the field by focusing on the genomic instability and phenotypic dynamics of metastatic tumor cells.19.
D. Jacob C. Deborde M. Lefebvre M. Maucourt A. Moing 《Metabolomics : Official journal of the Metabolomic Society》2017,13(4):36
Introduction
Concerning NMR-based metabolomics, 1D spectra processing often requires an expert eye for disentangling the intertwined peaks.Objectives
The objective of NMRProcFlow is to assist the expert in this task in the best way without requirement of programming skills.Methods
NMRProcFlow was developed to be a graphical and interactive 1D NMR (1H & 13C) spectra processing tool.Results
NMRProcFlow (http://nmrprocflow.org), dedicated to metabolic fingerprinting and targeted metabolomics, covers all spectra processing steps including baseline correction, chemical shift calibration and alignment.Conclusion
Biologists and NMR spectroscopists can easily interact and develop synergies by visualizing the NMR spectra along with their corresponding experimental-factor levels, thus setting a bridge between experimental design and subsequent statistical analyses.20.