Density Gradient Centrifugation Research Articles

Transcriptomic analysis of spleen-derived macrophages in response to lipopolysaccharide shows dependency on the MyD88-independent pathway in Chinese giant salamanders (Andrias davidianus)

BackgroundGram-negative bacteria are the main bacterial pathogens infecting Chinese giant salamanders (Andrias davidianus; CGS) in captivity and the wild, causing substantial economic losses in the CGS industry. However, the molecular mechanisms underlying pathogenesis following infection remain unclear.ResultsSpleen-derived macrophages from healthy CGS were isolated, cultured, and identified using density gradient centrifugation and immunofluorescence. A macrophage transcriptome database was established 0, 6, and 12 h post lipopolysaccharide stimulation using RNA-sequencing. In the final database 76,743 unigenes and 4,698 differentially expressed genes (DEGs) were functionally annotated. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes enrichment results showed that DEGs were concentrated in toll-like receptor–nuclear factor kappa B-related immune pathways. Ten DEGs were validated 12 h after lipopolysaccharide (LPS) stimulation. Although the common LPS recognition receptor toll-like receptor 4 was not activated and the key adaptor protein MyD88 showed no significant response, we observed significant up-regulation of the following adaptors: toll/interleukin-1 receptor domain-containing adaptor inducing interferon-β, tumour necrosis factor receptor-associated factor 6, and transforming growth factor-β activated kinase 1, which are located downstream of the non-classical MyD88 pathway.ConclusionsIn contrast to that in other species, macrophage activation in CGS could depend on the non-classical MyD88 pathway in response to bacterial infection. Our study provides insights into the molecular mechanisms regulating CGS antibacterial responses, with implications for disease prevention and understanding immune evolution in amphibians.

Hepatic Stellate Cell-mediated Increase in CCL5 Chemokine Expression after X-ray Irradiation Determined In Vitro and In Vivo.

Radiation exposure causes hepatitis which induces hepatic steatosis and fibrosis. Although hepatic stellate cells (HSCs) have been considered potential pathological modulators for the development of hepatitis due to viral and microbial infections, their involvement in radiation-induced hepatitis is yet to be determined. This study aimed to clarify the relationship between radiation exposure and expressions of inflammatory cytokines and chemokines in HSCs in vitro and invivo. HSCs were obtained from 1-week-old mice, known to be highly sensitive to radiation-induced hepatocellular carcinoma, using a newly established method combining liver perfusion, cell dissociation, and density gradient centrifugation, followed by magnetic negative selection of hematopoietic and endothelial cells with anti-CD45.2 and CD146 antibodies. The isolated HSCs were confirmed by the expression of desmin and glial fibrillary acidic protein (GFAP). We demonstrated that primary cultured HSCs, exposed to X-ray irradiation (0, 1.9, and 3.8 Gy) and cultured for 3 and 7 days, produced elevated levels of C-C motif chemokine ligand 5 (CCL5, also known as RANTES) inflammatory chemokine in a dose-dependent manner. An invivo immunofluorescence method confirmed that increased CCL5 signals were observed in GFAP-positive HSCs in mouse livers 7 days after whole-body X-ray irradiation (1.9 and 3.8 Gy). Adequate expression of C-C motif chemokine receptor 5 (Ccr5), a receptor for CCL5, was also detected using real-time PCR in the liver of both irradiated and non-irradiated mice. Taken together, our data suggest that HSCs may drive hepatitis via CCL5/CCR5 axis in the liver under radiation-induced stress. Furthermore, this newly established experimental protocol can help evaluate the expression of other inflammatory cytokines in primary cultures of HSCs isolated from infant mice.

Immune alterations in children with autism spectrum disorders

Autism spectrum disorders (ASD) are a heterogeneous group of mental and nervous system disorders. Patients with ASD are characterized by communication and cognitive impairments and obsessive behavior. The pathogenesis and etiology of ASD are still unclear. According to the literature, patients suffering from ASD have not only mental, but also somatic disorders, including changes in the immune system. The aim of this work was to study the concentration of cytokines in the blood plasma of children with ASD and the level of expression of proinflammatory genes in peripheral blood mononuclear cells. The clinical group included 71 children aged 4-12 years with a diagnosis of ASD (F84.02). Patients scored more than 36 on the Childhood Autism Rating Scale (CARS). The control sample included 27 apparently healthy children of the same age. The following methods were used in this study: isolation of mononuclear cells from heparinized peripheral blood, Ficoll-Verografin density gradient centrifugation, evaluation of cytokine blocks using commercially available enzyme immunoassay kits, isolation of random total RNA, reverse transcription using hexaprimers, and real-time polymerase chain reaction using intercalating dye SYBR Green. The concentration of proinflammatory cytokines IL-1β, IL-8, and IL-17A in the peripheral blood plasma of children with ASD was statistically significantly increased compared to the control sample. Moreover, the concentration of the anti-inflammatory cytokine IL-10 in patients with ASD was 3.6 times lower compared to the control sample (p 0.001). The level of expression of the NF-κB1, IL1β, IL8 and TNFα genes at the RNA level in peripheral blood mononuclear cells was increased by 2.8, 2.5, 4.8 and 4.2 times in patients with ASD compared to the control sample (all p 0.01). The results obtained indicate an increase in the concentration of proinflammatory cytokines (IL-1β, IL-8, IL-17A) in the blood plasma and a decrease in the concentration of anti-inflammatory cytokines (IL-10) in patients with ASD compared to the control sequence.

Transcriptional pathways of terminal differentiation in high- and low-density blood granulocytes in sepsis

BackgroundTrauma and infection induce emergency granulopoiesis. Counts of immature granulocytes and transcriptional pathways of terminal granulocytic differentiation in blood are elevated in sepsis but correlate with disease severity. This limits their performance as sepsis biomarkers in critically ill patients. We hypothesized that activation of these pathways in sepsis is attributable to immature low-density (LD) rather than mature high-density (HD) granulocytes.MethodsWe included patients with sepsis and systemic inflammatory response syndrome (SIRS) of comparable disease severity, and additionally septic shock, on intensive or intermediate care unit admission. Blood granulocyte isolation by CD15 MicroBeads was followed by density-gradient centrifugation. Flow cytometry was used to determine counts of developmental stages (precursors) and their relative abundancies in total, HD, and LD granulocytes. Five degranulation markers were quantified in plasma by multiplex immunoassays. A set of 135 genes mapping granulocyte differentiation was assayed by QuantiGene™ Plex. CEACAM4, PLAC8, and CD63 were analyzed by qRT-PCR. Nonparametric statistical tests were applied.ResultsPrecursor counts appeared higher in sepsis than SIRS but did not correlate with disease severity for early immature and mature granulocytes. Precursor subpopulations were enriched at least ten-fold in LD over HD granulocytes without sepsis-SIRS differences. Degranulation markers in blood were comparable in sepsis and SIRS. Higher expression of early developmental genes in sepsis than SIRS was more pronounced in LD and less in HD than total granulocytes. Only the cell membrane protein encoding genes CXCR2 and CEACAM4 were more highly expressed in SIRS than sepsis. By qRT-PCR, the azurophilic granule genes CD63 and PLAC8 showed higher sepsis than SIRS levels in LD granulocytes and PLAC8 also in total granulocytes where its discriminatory performance resembled C-reactive protein (CRP).ConclusionsTranscriptional programs of early terminal granulocytic differentiation distinguish sepsis from SIRS due to both higher counts of immature granulocytes and elevated expression of early developmental genes in sepsis. The sustained expression of PLAC8 in mature granulocytes likely accounts for its selection in the whole blood SeptiCyte™ LAB test. Total granulocyte PLAC8 rivals CRP as sepsis biomarker. However, infection-specific transcriptional pathways, that differentiate sepsis from sterile stress-induced granulocytosis more reliably than CRP, remain to be identified.

Seasonal variability of epipelic microphytobenthos community in two subtidal areas of the Northern Adriatic Sea

We investigated the biodiversity and seasonality of subtidal benthic diatoms at two sites of the Northern Adriatic Sea differently affected by anthropogenic inputs. Sediment samples were collected seasonally, and diatom cells were then separated from the sediment using the density gradient centrifugation method. The total abundance of benthic diatoms ranged between 4,409 ± 1,638 and 77,663 ± 30,415 cells cm-2 and the biomass between 0.41 ± 0.22 and 3.66 ± 2.01 μg C cm-2. At both stations, the benthic diatoms showed a marked seasonal pattern, with maximum abundance, biomass and biodiversity in spring and minimum in summer. Motile life forms, such as Navicula, Nitzschia, Fallacia, and Psammodictyon, dominated in terms of abundance at both stations throughout the study period, while plocon (centric diatoms mainly belonging to Biddulphiaceae) increased under mixing conditions, when they represented the largest contributor to biomass. At both stations and in all seasons, the Si:N:P ratio highlighted the strong P limitation, typical of the Adriatic Sea. The ammonium concentration was the highest component of DIN in spring and summer when we observed the highest and lowest MPB abundance respectively. The preference of diatoms for ammonia, coupled with the increased daylight period, may have enhanced the spring growth, whereas in summer the hypoxic conditions may have caused a decrease. Despite the different environmental conditions, the two stations exhibited similar species compositions and seasonal trends, highlighting relative stability against anthropogenic pressures of a different nature.

Peripheral Blood Mononuclear Cell Transcriptome of Dairy Cows Naturally Infected with Bovine Leukemia Virus.

The current literature has identified many abnormalities in the immune expression of cows infected with the bovine leukemia virus (BLV). These studies have focused on individual cell, gene, or protein expression, failing to provide a comprehensive understanding of the changes in immune expression in animals with BLV. To identify the overall alterations in immune expression during BLV infection, the transcriptomes of the peripheral blood mononuclear cells (PBMCs) of cows seropositive or seronegative for BLV antibodies were sequenced. Whole blood samples were collected from 20 dairy cows and screened for BLV antibodies and PCR was used to quantify the proviral load of the samples. PBMCs were separated from whole blood using density gradient centrifugation from which RNA was isolated and sequenced. Three seropositive samples (BLV+; n = 3), including one of each PVL category, low (n = 1), moderate (n = 1), and high (n = 1), and three seronegative samples (BLV-; n = 3) were sequenced for differential gene expression analysis. The results showed major differences in the transcriptome profiles of the BLV+ and BLV- PBMCs and revealed a wide variety of immunological pathways affected by BLV infection. Our results suggest that disease state and PBMC gene expression vary depending on BLV proviral load levels and that BLV causes the suppression of normal immune responses and influences B and T cell gene expression, resulting in immune dysfunction.

Population pharmacokinetics of tacrolimus whole blood and peripheral blood mononuclear cell concentrations in stable kidney-transplanted patients.

Therapeutic drug monitoring of tacrolimus based on whole blood drug concentrations is routinely performed. The concentration of tacrolimus in peripheral blood mononuclear cells (PMBCs) is likely to better reflect drug exposure at the treatment target site. We aimed to describe the relationship between tacrolimus whole blood and PBMC concentrations, and the influence of patient characteristics on this relationship by developing a population pharmacokinetic model. We prospectively enrolled 63 stable adult kidney-transplanted patients and collected dense (12-h, n = 18) or sparse (4-h, n = 45) pharmacokinetic profiles of tacrolimus. PBMCs were isolated from whole blood (Ficoll density gradient centrifugation), and drug concentrations in whole blood and PBMCs were analysed using liquid chromatography-mass spectrometry. Patient genotype (CYP3A4/5, ABCB1, NR1I2) was assessed with PCR. Population pharmacokinetic modelling and statistical evaluation was performed using NONMEM. Tacrolimus whole blood concentrations were well described using a two-compartment pharmacokinetic model with a lag-time and first-order absorption and elimination. Tacrolimus PBMC concentrations were best estimated from whole blood concentrations with the use of a scaling factor, the ratio of whole blood to PBMC concentrations (RC:PBMC), which was the extent of tacrolimus distribution into PBMC. CYP3A5*1 non-expressors and NR1I2-25 385T allele expressors demonstrated higher RC:PBMC ratios of 42.4% and 60.7%, respectively. Tacrolimus PBMC concentration could not be accurately predicted from whole blood concentrations and covariates because of significant residual unexplained variability in the distribution of tacrolimus into PBMCs and may need to be measured directly if required for future studies.

Schistosoma japonicum infection-mediated downregulation of lncRNA Malat1 contributes to schistosomiasis hepatic fibrosis by the Malat1/miR-96/Smad7 pathway

BackgroundSchistosoma japonicum infection causes hepatic fibrosis, a primary cause of morbidity and mortality associated with the disease, and effective treatments are still lacking. Long non-coding RNAs (lncRNAs) have been implicated in the pathogenic process of various tissue fibroses. However, the role of lncRNAs in schistosomiasis hepatic fibrosis (HF) is poorly understood. Understanding the role of lncRNAs in schistosomiasis HF will enhance knowledge of disease processes and aid in the discovery of therapeutic targets and diagnostic biomarkers.MethodsDifferentially expressed lncRNA profiles in primary hepatic stellate cells (HSCs) of mice infected with S. japonicum were identified using high-throughput lncRNA sequencing. Primary HSCs were isolated from infected mice using collagenase digestion and density-gradient centrifugation, cultured in DMEM with 10% fetal bovine serum. Dual-luciferase reporter assays, nuclear cytoplasm fractionation and RIP assays were employed to assess the relationship between Malat1 and miRNA-96. Malat1 lentivirus and ASO-Malat1 were constructed for forced expression and downregulated expression of Malat1. The Malat1-KO mouse was constructed by CRISPR/Cas9 technology. Pathological features of the liver were evaluated by hematoxylin-eosin (HE), Masson’s trichrome staining and immunohistochemistry (IHC). The expression levels of fibrosis-related genes were determined by quantitative real-time PCR (qRT-PCR) and Western blot.ResultsA total of 1561 differentially expressed lncRNAs were identified between infected and uninfected primary HSCs. Among the top altered lncRNAs, the downregulated Malat1 was observed in infected HSCs and verified by qPCR. Treatment of infected mice with praziquantel (PZQ) significantly increased the Malat1 expression. Elevated Malat1 expression in infected primary HSC reduced the expressions of profibrogenic genes, whereas Malat1 knockdown had the opposite effect. Moreover, Malat1 was found to interact with miR-96, a profibrotic miRNA, by targeting Smad7. Forced Malat1 expression reduced miR-96 levels in infected primary HSCs, attenuating fibrogenesis and showing negative correlation between Malat1 expression and the expression levels of miR-96 and profibrogenic genes α-SMA and Col1α1. Notably, in Malat1-KO mice, knockout of Malat1 aggravates schistosomiasis HF, while restored Malat1 expression in the infected HSCs reduced the expression of profibrogenic genes.ConclusionsWe demonstrate that lncRNA is involved in regulation of schistosomiasis HF. Elevated lncRNA Malat1 expression in infected HSCs reduces fibrosis via the Malat1/miR-96/Smad7 pathway, thus providing a novel therapeutic target for schistosomiasis HF. Furthermore, Malat1 expression is sensitive to PZQ treatment, thus offering a potential biomarker for assessing the response to chemotherapy.Graphical abstract

Investigation of optimal sperm storage conditions for short-term storage

Objective The quality of sperm cells is important role in the success rates of assisted reproduction technology (ART) treatments. The quality of the sperm cells shows variations depending on the temperature of short-term semen storage as well as the methods of semen preparation. Thus, this study aimed to investigate the sperm viability, motility and DNA fragmentation following different sperm preparation methods and short-term storage conditions, respectively. Materials and Methods A total of 25 semen samples were evaluated. In the first part of this study, different incubation temperatures were investigated in two groups, in such the first group involved the semen samples and the second group involved the sperm cells separated by density gradient centrifugation method, respectively. The samples in each group were incubated at 4°C, room temperature (21°C) and 37°C for 24 hours, respectively. The sperm cell qualities were evaluated by mobility analysis, DNA fragmentation by acridine orange staining and sperm cell viability by propidium iodide staining. Results and Discussion The analysis outcome demonstrated that the mobility, DNA fragmentation and viability of the sperm cells were statistically different when incubated at RT (21°C) in both groups. Furthermore, samples prepared by the density gradient centrifugation method were shown to have better quality. The optimum short-term storage temperature was detected to be the room temperature. Conclusion The conclusion of this investigation is crucial to assess storage conditions in ART clinics. This study provides essential data for short-term sperm storage and preparation methods to improve the success rates of ART clinics. Bangladesh Journal of Medical Science Vol. 23 No. 04 October’24 Page : 1137-1141

B-220 Clinical Application of the “Clg-Fish” Technique for the Diagnosis of Multiple Myeloma

Abstract Background The international standard system [R2-ISS] for Multiple Myeloma (MM) includes genetic characteristics of malignant cells by fluorescent in situ hybridization -t(4;14), del(17p) and t(14;16) at diagnosis; We included interphase fluorescent in situ hybridization (cIg-FISH) of purified CD138 cells in this evaluation. The aim of this study is to evaluate the implementation of cIg-FISH in MM for disease diagnosis and stratification. Methods oBone marrow [BM] from patients with MM diagnosed by the European Myeloma Network (REM) criteria were evaluated. BM mononuclear cells obtained by density gradient centrifugation for 30 minutes, with Ficoll-Hypaque density medium; followed by immunoassay with anti-Kappa/anti-Lambda antibodies labeled with FISH probes. We detected the following abnormalities: t(4;14), t(14;16) and deletion of 17p13. The t(11;14) and the amplification/deletion of 1q21-q22 (CKS1B)/1p32.3 (CDKN2C). We used the probes: TP53, IGH::FGFR3, IGH::CCND1, IGH:MAF and CKS1B/CDKN2C, one hundred cells per probe. Signals exceeding the cutoff recommended by REM were considered abnormal. The viability of the method was tested on samples 24, 48 and 72 hours after collection. Results Genetic aberrations seen in 24 and 48 hs plasma cells, a specific rearrangement of 14q32.33 t(4;14) in the 48 hs sample; Samples processed for 72 hours resulted in cells that were unviable for analysis. Genetic aberrations were detected by cIg-FISH in cells from 40% of patients. We detected the following abnormalities t(4;14) (Fig.1A), del(17p) (Fig. 1B); deletion of 1p32.3 amplification (CDKN2C) 1q21 (Fig. 1 C-D). The cIg-FISH study detected genetic aberrations in MM as those recommended by the European Myelomat Network - t(4;14), t(14;16) and del(17p), by FISH analysis for risk stratification for MM. Conclusions The inclusion of cIg-FISH in risk stratification systems has clinical relevance because cIg-FISH is a standard tool for detecting genetic abnormalities and prognosing the disease.

Chitinase and proteinase K treatments enhance the DNA yield of microsporidium Ecytonucleospora hepatopenaei spores

Microsporidium Ecytonucleospora hepatopenaei (EHP) spores were purified from the hepatopancreas of Penaeus vannamei infected with EHP by percoll density gradient centrifugation and differential centrifugation. The EHP spores contain a thick chitin wall and might not rupture using the routine DNA extraction protocol. In this study, three enzymes were used, including chitinase, proteinase K, and DNase I. Chitinase or proteinase K digestions caused weakened fluorescence of chitin showing by a blurred edge of EHP spores stained with calcofluor white under a fluorescence microscope. Different combinations of these enzymes followed by DNA extraction with phenol–chloroform from EHP spores showed significant increases in the copy number of the EHP SSU gene per spore. The combination of the chitinase and proteinase K treatments resulted 4.46 ± 1.07 copies/spore detected, which is 31.6 ± 20.7 folds of no treatment groups, accounting to (55.7 ± 13.4)% of the total copies of the gene in the spore. The additional treatment with chitinase to the conventional extraction protocol with a proteinase K digestion step for feces and hepatopancreas samples of P. vannamei resulted in a significant difference in EHP copies in the DNA of (83.8 ± 64.1)% and (55.3 ± 88.0)% increases. The study proved that chitinase and proteinase K treatment enhance the DNA extraction from microsporidian spores resulting in high yield.

An evaluation of the analytical and biological robustness of a method for quantifying iron in individual red blood cells via single-cell tandem ICP-mass spectrometry

This work evaluated the analytical and biological robustness of iron (Fe) determination in individual red blood cells (RBCs) via single-cell ICP-MS (SC-ICP-MS). RBCs were separated from other whole blood constituents using Ficoll-Paque™ density gradient centrifugation. While fixation with paraformaldehyde (PFA) led to RBC lysis, the use of glutaraldehyde (GA) left the RBCs intact and permitted storage of RBC cell suspensions in ultra-pure water for up to 16 months at 4 °C. GA-fixation also rendered the RBCs sufficiently robust to maintain integrity during their introduction into the ICP by means of nebulization of dilute suspensions. Obtaining quantitative data on a cell-per-cell basis required determination of the transport efficiency using the particle size method and external calibration against aqueous Fe standard solutions. The average Fe content per RBC obtained using SC-ICP-MS (average value of 103 fg/cell) agreed well with the value obtained using solution-based ICP-MS obtained after cell pellet digestion and with values obtained from literature. Variation of the cell number density in the suspensions analyzed between 1.5 × 105 and 6.0 × 105 cells per mL did not affect the result. Identical results from one-week interval blood drawings from healthy individuals demonstrate biological consistency. Compared to bulk analysis, the SC-ICP-MS approach offers the added value of providing information on the cell-to-cell heterogeneity in Fe content.

Single-cell RNA sequencing reveals surface markers of primordial germ cells in chicken and zebra finch.

Primordial germ cells (PGCs) in avian species exhibit unique developmental features, including the ability to migrate through the bloodstream and colonize the gonads, allowing their isolation at various developmental stages. Several methods have been developed for the isolation of avian PGCs, including density gradient centrifugation, size-dependent separation, and magnetic-activated cell sorting (MACS) or fluorescence-activated cell sorting (FACS) using a stage-specific embryonic antigen-1 (SSEA-1) antibody. However, these methods present limitations in terms of efficiency and applicability across development stages. In particular, the specificity of SSEA-1 decreases in later developmental stages. Furthermore, surface markers that can be utilized for isolating or utilizing PGCs are lacking for wild birds, including zebra finches, and endangered avian species. To address this, we used single-cell RNA sequencing (scRNA-seq) to uncover novel PGC-specific surface markers in chicken and zebra finch. We screened for genes that were primarily expressed in the PGC population within the gonadal cells. Analyses of gene expression patterns and levels based on scRNA-seq, coupled with validation by RT-PCR, identified NEGR1 and SLC34A2 as novel PGC-specific surface markers in chickens and ESYT3 in zebra finches. Notably, these newly identified genes exhibited sustained expression not only during later developmental stages but also in reproductive tissues.

Assessing the effects of ex vivo hormonal exposure on oxidative responses in equine leukocytes: A preliminary study

Breed differences exist between horses and ponies in circulating concentrations of several hormones, notably ACTH and insulin. These hormones regulate stress and metabolic responses, but in other species, they also impact leukocyte oxidant responses. The effects of these hormones on equine leukocytes have not been evaluated to date. If equine leukocytes are similarly regulated, breed differences in increased plasma hormone concentrations or altered sensitivity to them at the leukocyte level could result in breed-related differences in oxidant responses or oxidative status. The objective of this study was therefore to determine the effects of ex vivo exposure to adrenocorticotropic hormone (ACTH), α-melanocyte stimulating hormone (α-MSH), insulin, or leptin on reactive oxygen species (ROS) production from leukocytes isolated from horses and ponies. We hypothesized that ACTH, α-MSH, insulin, and leptin would alter oxidant responses from equine leukocytes in a breed specific manner. Blood was collected from 10 apparently healthy Quarter horses and seven Welsh ponies for isolation of neutrophils and peripheral blood mononuclear cells (PBMCs) via density gradient centrifugation. Cells were incubated with media (negative control), microbial antigens (positive control), or ACTH, α-MSH, leptin, or insulin for two hours. Induced ROS production was quantified with a previously validated fluorometric assay. Data was compared within groups by comparing a stimulant within a group (horses or ponies) to baseline, between groups by comparing horse response to pony response, and among stimulants using one- and two-way, repeated measures ANOVA (P<0.05). There was no significant effect of breed on basal, microbial-induced, or hormone-induced ROS production from neutrophils (P=0.465) or PBMCs (P=0.749), but in neutrophils, a significant interaction between breed and stimulant was present (P=0.037). ROS production from PBMCs from horses after hormone exposure did not differ from cells exposed to media only (P=0.1520–0.8180). Similarly, neither leptin nor insulin exposure significantly induced ROS production from PBMCs from ponies (P= 0.2645 and 0.4678 respectively), but exposure to ACTH or α-MSH induced a significant increase in ROS production (P=0.0441 and 0.0440 respectively) compared to unstimulated cells. Hormones that vary in availability among breeds may induce ex vivo pro-oxidant responses in equine leukocytes, but specific effects are breed-, leukocyte type-, and hormone-dependent. Breed differences in hormonally induced leukocyte ROS production may warrant further investigation in the context of circulating oxidative stress and how this might relate to future disease risk.

A Method for Separating and Quantifying Organic and Inorganic Ice Nucleating Substances Based on Density Gradient Centrifugation

A Method for Separating and Quantifying Organic and Inorganic Ice Nucleating Substances Based on Density Gradient Centrifugation

Density Gradient Centrifugation Is an Effective Tool to Isolate Cancer Stem-like Cells from Hypoxic and Normoxia Triple-Negative Breast Cancer Models.

Accumulating evidence has indicated that stemness-related genes are associated with the aggressiveness of triple-negative breast cancer (TNBC). Because no universal markers for breast CSCs are available, we applied the density gradient centrifugation method to enrich breast CSCs. We demonstrated that the density centrifugation method allows for the isolation of cancer stem cells (CSCs) from adherent and non-adherent MCF7 (Luminal A), MDA-MB-231 (TNBC) and MDA-MB-468 (TNBC) breast cancer cells. The current study shows that the CSCs' enriched fraction from Luminal A and TNBC cells have an increased capacity to grow anchorage-independently. CSCs from adherent TNBC are mainly characterized by metabolic plasticity, whereas CSCs from Luminal A have an increased mitochondrial capacity. Moreover, we found that non-adherent growth CSCs isolated from large mammospheres have a higher ability to grow anchorage-independently compared to CSCs isolated from small mammospheres. In CSCs, a metabolic shift towards glycolysis was observed due to the hypoxic environment of the large mammosphere. Using a bioinformatic analysis, we indicate that hypoxia HYOU1 gene overexpression is associated with the aggressiveness, metastasis and poor prognosis of TNBC. An in vitro study demonstrated that HYOU1 overexpression increases breast cancer cells' stemness and hyperactivates their metabolic activity. In conclusion, we show that density gradient centrifugation is a non-marker-based approach to isolate metabolically flexible (normoxia) CSCs and glycolytic (hypoxic) CSCs from aggressive TNBC.

Transplantation of miR-145a-5p modified M2 type microglia promotes the tissue repair of spinal cord injury in mice

BackgroundThe traumatic spinal cord injury (SCI) can cause immediate multi-faceted function loss or paralysis. Microglia, as one of tissue resident macrophages, has been reported to play a critical role in regulating inflammation response during SCI processes. And transplantation with M2 microglia into SCI mice promotes recovery of motor function. However, the M2 microglia can be easily re-educated and changed their phenotype due to the stimuli of tissue microenvironment. This study aimed to find a way to maintain the function of M2 microglia, which could exert an anti-inflammatory and pro-repair role, and further promote the repair of spinal cord injury.MethodsTo establish a standard murine spinal cord clip compression model using Dumont tying forceps. Using FACS, to sort microglia from C57BL/6 mice or CX3CR1GFP mice, and further culture them in vitro with different macrophage polarized medium. Also, to isolate primary microglia using density gradient centrifugation with the neonatal mice. To transfect miR-145a-5p into M2 microglia by Lipofectamine2000, and inject miR-145a-5p modified M2 microglia into the lesion sites of spinal cord for cell transplanted therapy. To evaluate the recovery of motor function in SCI mice through behavior analysis, immunofluorescence or histochemistry staining, Western blot and qRT-PCR detection. Application of reporter assay and molecular biology experiments to reveal the mechanism of miR-145a-5p modified M2 microglia therapy on SCI mice.ResultsWith in vitro experiments, we found that miR-145a-5p was highly expressed in M2 microglia, and miR-145a-5p overexpression could suppress M1 while promote M2 microglia polarization. And then delivery of miR-145a-5p overexpressed M2 microglia into the injured spinal cord area significantly accelerated locomotive recovery as well as prevented glia scar formation and neuron damage in mice, which was even better than M2 microglia transplantation. Further mechanisms showed that overexpressed miR-145a-5p in microglia inhibited the inflammatory response and maintained M2 macrophage phenotype by targeting TLR4/NF-κB signaling.ConclusionsThese findings indicate that transplantation of miR-145a-5p modified M2 microglia has more therapeutic potential for SCI than M2 microglia transplantation from epigenetic perspective.Graphical

Metagenomic Insights Reveal Unrecognized Diversity of Entotheonella in Japanese Theonella Sponges.

Numerous biologically active natural products have been discovered from marine sponges, particularly from Theonella swinhoei, which is known to be a prolific source of natural products such as polyketides and peptides. Recent studies have revealed that many of these natural products are biosynthesized by Candidatus Entotheonella phylotypes, which are uncultivated symbionts within T. swinhoei. Consequently, Entotheonella is considered an untapped biochemical resource. In this study, we conducted metagenomic analyses to assess the diversity of Entotheonella in two T. swinhoei Y and two T. swinhoei W (Y and W referring to the yellow and white interior of the sponge, respectively), after separating filamentous bacteria using density gradient centrifugation. We obtained five Entotheonella metagenome-assembled genomes (MAGs) from filamentous bacteria-enriched fractions. Notably, one of these MAGs is significantly different from previously reported Entotheonella variants. Additionally, we identified closely related Entotheonella members present across different chemotypes of T. swinhoei. Thus, our metagenomic insights reveal that the diversity of Entotheonella within Theonella sponges is greater than previously recognized.

Differential composition and yield of leukocytes isolated from various blood component leukoreduction filters

In Flanders, an estimated 300,000 leukoreduction filters are discarded as biological waste in the blood establishment each year. These filters are a possible source of fresh donor leukocytes for downstream purposes including research. We investigated leukocyte isolation from two types of filters either used for the preparation of platelet concentrates (PC-LRF) or erythrocyte concentrates (EC-LRF). Outcome parameters were leukocyte yield, differential count, turnaround time and effect of storage conditions. Leukocytes were harvested by reverse flow of a buffer solution. Control was the gold standard density gradient centrifugation of buffy coats. Total leukocyte number isolated from PC-LRF (1049 (± 40) x 106) was almost double that of control (632 (± 66) x 106) but the differential count was comparable. Total leukocyte number isolated from EC-LRF (78 (± 9) x 106) was significantly lower than control, but the sample was specifically enriched in granulocytes (81 ± 4%) compared to control (30 ± 1%). Isolation of leukocytes from either PC- or EC-LRF takes 20 min compared to 240 min for control density gradient centrifugation. Leukocyte viability is optimal when harvested on day 1 post donation (95 ± 0.9%) compared to day 3 (76.4 ± 2.4%). In conclusion, our study demonstrates that leukoreduction filters from specific blood component processing are easy to use and present a valuable source for viable leukocytes of all types.

A hyaluronic acid-containing reagent compatible with glass-bottom dishes and capable of sustained binding of human spermatozoa.

Commercial products currently available for sperm selection utilizing hyaluronic acid (HA) binding prior to intracytoplasmic sperm injection (ICSI) are widely used but have some disadvantages. To potentially circumvent these limitations, we compared ICSI using a self-made hyaluronic acid (smHA) reagent with ICSI using SpermSlow. The binding of the reagents to spermatozoa on plastic- or glass-bottom dishes was quantitated using spermatozoa that were isolated by density-gradient centrifugation and swim-up procedures (N=10/group). Additionally, we investigated the relationship between the HA reagent used prior to ICSI and clinical outcomes after assisted reproduction with HA-ICSI (N=81). The smHA reagent exhibited extremely stable binding to human spermatozoa. The binding time of spermatozoa was significantly longer in the smHA reagent than in SpermSlow on both plastic and glass dishes (plastic: 60.0±0.0 min vs. 2.7±5.9 min, P<0.001; glass: 60.0±0.0 min vs. 2.5±1.8 min, P<0.001). There were no significant differences in the normal fertilization rate between HA-ICSI with the smHA reagent (128/160, 80.0%) and HA-ICSI with SpermSlow (171/231, 74.0%, P=0.184). The frequency of the blastocyst development from the HA-ICSI-derived zygote was significantly higher with the smHA reagent (74/101, 73.3%) than with SpermSlow (76/131, 58.0%, P=0.019). The rates of biochemical pregnancy, clinical pregnancy, fetal heart movement, live birth, and miscarriage were not significantly different between HA-ICSI with the smHA reagent and HA-ICSI with SpermSlow. The blastulation rate was higher for HA-ICSI with the smHA reagent as compared with SpermSlow. Clinical outcomes, excluding blastulation, after HA-ICSI were the same using smHA reagent and using SpermSlow. Spermatozoa binding to the smHA reagent was not attenuated over a 60-min time course. In conclusion, this reagent may shorten and simplify HA-ICSI procedures because smHA can be used with any dish material, making it easier to observe the spindle or assess intracytoplasmic morphology.