Mesenchymal stromal cell (MSC)-based therapies are being actively investigated in various inflammatory disorders. However, functional variability among MSCs cultured in vitro will lead to distinct ...therapeutic efficacies. Until now, the mechanisms behind immunomodulatory functional variability in MSCs are still unclear.
We systemically investigated transcriptomic variations among MSC samples derived from multiple tissues to reveal their effects on immunomodulatory functions of MSCs. We then analyzed transcriptomic changes of MSCs licensed with INFγ to identify potential molecular mechanisms that result in distinct MSC samples with different immunomodulatory potency.
MSCs were clustered into distinct groups showing different functional enrichment according to transcriptomic patterns. Differential expression analysis indicated that different groups of MSCs deploy common regulation networks in response to inflammatory stimulation, while expression variation of genes in the networks could lead to different immunosuppressive capability. These different responsive genes also showed high expression variability among unlicensed MSC samples. Finally, a gene panel was derived from these different responsive genes and was able to regroup unlicensed MSCs with different immunosuppressive potencies.
This study revealed genes with expression variation that contribute to immunomodulatory functional variability of MSCs and provided us a strategy to identify candidate markers for functional variability assessment of MSCs.
The outbreak of COVID-19 has posed a huge threat to global health and economy. Countermeasures have revolutionized norms for working, socializing, learning, and travel. Importantly, vaccines have ...been considered as most effective tools to combat with COVID-19. As of the beginning of 2021, >200 COVID-19 vaccine candidates, covering nearly all existing technologies and platforms, are being research and development (R&D) by multiple manufacturers worldwide. This has posed a huge obstacle to the quality control and evaluation of those candidate vaccines, especially in China, where five vaccine platforms are deployed in parallel. To accelerate the R&D progress of COVID-19 vaccines, the guidances on R&D of COVID-19 vaccine have been issued by National Regulatory Authorities or organizations worldwide. The Center for Drug Evaluation and national quality control laboratory in China have played a leading role in launching the research on quality control and evaluation in collaboration with relevant laboratories involved in the vaccine R&D, which greatly supported the progression of vaccines R&D, and accelerated the approval for emergency use and conditional marketing of currently vaccine candidates. In this paper, the progress and experience gained in quality control and evaluation of COVID-19 vaccines developed in China are summarized, which might provide references for the R&D of current and next generation of COVID-19 vaccines worldwide.
Lamellar bodies (LBs) are lysosome-related organelles (LROs) of surfactant-producing alveolar type 2 (AT2) cells of the distal lung epithelium. Trafficking pathways to LBs have been understudied but ...are likely critical to AT2 cell homeostasis given associations between genetic defects of endosome to LRO trafficking and pulmonary fibrosis in Hermansky Pudlak syndrome (HPS). Our prior studies uncovered a role for AP-3, defective in HPS type 2, in trafficking Peroxiredoxin-6 to LBs. We now show that the P4-type ATPase ATP8A1 is sorted by AP-3 from early endosomes to LBs through recognition of a C-terminal dileucine-based signal. Disruption of the AP-3/ATP8A1 interaction causes ATP8A1 accumulation in early sorting and/or recycling endosomes, enhancing phosphatidylserine exposure on the cytosolic leaflet. This in turn promotes activation of Yes-activating protein, a transcriptional coactivator, augmenting cell migration and AT2 cell numbers. Together, these studies illuminate a mechanism whereby loss of AP-3-mediated trafficking contributes to a toxic gain-of-function that results in enhanced and sustained activation of a repair pathway associated with pulmonary fibrosis.
Bacterial DNA has been reported in the placenta and amniotic fluid by several independent groups of investigators. However, it's taxonomic overlap with fetal and maternal bacterial DNA in different ...sites has been poorly characterized. Here, we determined the presence of bacterial DNA in the intestines and placentas of fetal mice at gestational day 17 (n = 13). These were compared to newborn intestines (n = 15), maternal sites (mouth, n = 6; vagina, n = 6; colon, n = 7; feces, n = 8), and negative controls to rule out contamination. The V4 region of the bacterial 16S rRNA gene indicated a pattern of bacterial DNA in fetal intestine similar to placenta but with higher phylogenetic diversity than placenta or newborn intestine. Firmicutes were the most frequently assignable phylum. SourceTracker analysis suggested the placenta as the most commonly identifiable origin for fetal bacterial DNA, but also over 75% of fetal gut genera overlapped with maternal oral and vaginal taxa but not with maternal or newborn feces. These data provide evidence for the presence of bacterial DNA in the mouse fetus.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The purpose of this study was to investigate the therapeutic effects of genetically modified mesenchymal stem cells (MSCs) in the treatment of type 2 diabetes mellitus (T2DM) in order to identify a ...new method for treating diabetes that differs from traditional medicine and to provide a new means by which to fundamentally improve or treat diabetes.
MSCs derived from adipose tissue were modified to overexpress FGF21 and GLP1, which was achieved through lentiviral particle transduction. The cells were transplanted into BKS.Cg-Dock7m+/+Leprdb/Nju mice (T2DM mouse model). Injections of physiological saline (0.1 mL) and liraglutide (0.5 mg/kg) were used as negative and positive controls, respectively. ELISA or Western blotting was used for protein analysis, and quantitative real-time PCR was used for gene expression analysis.
Genetic modification had no effects on the morphology, differentiation ability, or immunophenotype of MSCs. Moreover, MSC-FGF21+GLP1 cells exhibited significantly increased secretion of FGF21 and GLP1. In the T2DM mouse model, the transplantation of MSC-FGF21+GLP1 cells ameliorated the changes in blood glucose and weight, promoted the secretion of insulin, enhanced the recovery of liver structures, and improved the profiles of lipids. Moreover, FGF21 and GLP1 exerted synergistic effects in the regulation of glucolipid metabolism by controlling the expression of insulin, srebp1, and srebp2.
Stem cell treatment based on MSCs modified to overexpress the FGF21 and GLP1 genes is an effective approach for the treatment of T2DM.
Experimental autoimmune encephalomyelitis (EAE) serves as a model for studying multiple sclerosis, with immunization strategies utilizing MOG35-55 peptide, emulsified in adjuvant enriched with ...mycobacterium tuberculosis (Mtb). This study examined the effects of Bacillus Calmette-Guérin (BCG) as an adjuvant, alongside the impact of MOG35-55 peptide doses and their residual counter ions on EAE development. We found that BCG can be effectively used to induce EAE with similar incidence and severity as heat-killed H37Ra, contingent upon the appropriate MOG35-55 peptide dose. Different immunization doses of MOG35-55 peptide significantly affect EAE development, with higher doses leading to a paradoxical reduction in disease activity, probably due to peripheral tolerance mechanisms. Furthermore, doses of MOG35-55 peptides with acetate showed a more pronounced effect on disease development compared to those containing trifluoroacetic acid (TFA), suggesting the potential influence of residual counter ions on EAE activity. We highlighted the feasibility of applying BCG to the establishment of EAE for the first time. Our findings emphasized the importance of MOG peptide dosage and composition in modulating EAE development, offering insights into the mechanisms of autoimmunity and tolerance. This could have implications for autoimmune disease research and the design of therapeutic strategies.
Necrotizing enterocolitis (NEC) is the most common surgical emergency in preterm infants, and pathogenesis associates with changes in the fecal microbiome. As fecal samples incompletely represent ...microbial communities in intestinal mucosa, we sought to determine the NEC tissue-specific microbiome and assess its contribution to pathogenesis.
We amplified and sequenced the V1-V3 hypervariable region of the bacterial 16S rRNA gene extracted from intestinal tissue and corresponding fecal samples from 12 surgical patients with NEC and 14 surgical patients without NEC. Low quality and non-bacterial sequences were removed, and taxonomic assignment was made with the Ribosomal Database Project. Operational taxonomic units were clustered at 97%. We tested for differences between NEC and non-NEC samples in microbiome alpha- and beta-diversity and differential abundance of specific taxa between NEC and non-NEC samples. Additional analyses were performed to assess the contribution of other demographic and environmental confounding factors on the infant tissue and fecal microbiome.
The fecal and tissue microbial communities were different. NEC was associated with a distinct microbiome, which was characterized by low diversity, higher abundances of Staphylococcus and Clostridium_sensu_stricto, and lower abundances of Actinomyces and Corynebacterium. Infant age and vancomycin exposure correlated with shifts in the tissue microbiome.
The observed low diversity in NEC tissues suggests that NEC is associated with a bacterial bloom and a distinct mucosal bacterial community. The exact bacterial species that constitute the bloom varied by infant and were strongly influenced by age and exposure to vancomycin.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Pre-existing immunity to Vaccinia Tian Tan virus (VTT) resulting from a large vaccination campaign against smallpox prior to the early 1980s in China, has been a major issue for application of ...VTT-vector based vaccines. It is essential to establish a sensitive and high-throughput neutralization assay to understand the epidemiology of Vaccinia-specific immunity in current populations in China.
A new anti-Vaccinia virus (VACV) neutralization assay that used the attenuated replication-competent VTT carrying the firefly luciferase gene of Photinus pyralis (rTV-Fluc) was established and standardized for critical parameters that included the choice of cell line, viral infection dose, and the infection time. The current study evaluated the maintenance of virus-specific immunity after smallpox vaccination by conducting a non-randomized, cross-sectional analysis of antiviral antibody-mediated immune responses in volunteers examined 30-55 years after vaccination. The rTV-Fluc neutralization assay was able to detect neutralizing antibodies (NAbs) against Vaccinia virus without the ability to differentiate strains of Vaccinia virus. We showed that the neutralizing titers measured by our assay were similar to those obtained by the traditional plaque reduction neutralization test (PRNT). Using this assay, we found a low prevalence of NAb to VTT (7.6%) in individuals born before 1980 from Beijing and Anhui provinces in China, and when present, anti-VTT NAb titers were low. No NAbs were detected in all 222 samples from individuals born after 1980. There was no significant difference observed for titer or prevalence by gender, age range and geographic origin.
A simplified, sensitive, standardized, reproducible, and high-throughput assay was developed for the quantitation of NAbs against different Vaccinia strains. The current study provides useful insights for the future development of VTT-based vaccination in Beijing and Anhui provinces of China.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
PDF
