Bortezomib restrains M2 polarization and reduces CXCL16-associated CXCR6+CD4 T cell chemotaxis in bleomycin-induced pulmonary fibrosis.

BACKGROUND: The development of pulmonary fibrosis involves a cascade of events, in which inflammation mediated by immune cells plays a pivotal role. Chemotherapeutic drugs have been shown to have dual effects on fibrosis, with bleomycin exacerbating pulmonary fibrosis and bortezomib alleviating tissue fibrotic processes. Understanding the intricate interplay between chemotherapeutic drugs, immune responses, and pulmonary fibrosis is likely to serve as the foundation for crafting tailored therapeutic strategies. METHODS: A model of bleomycin-induced pulmonary fibrosis was established, followed by treatment with bortezomib. Tissue samples were collected for analysis of immune cell subsets and functional assessment by flow cytometry and in vitro cell experiments. Additionally, multi-omics analysis was conducted to further elucidate the expression of chemokines and chemokine receptors, as well as the characteristics of cell populations. RESULTS: Here, we observed that the expression of CXCL16 and CXCR6 was elevated in the lung tissue of a pulmonary fibrosis model. In the context of pulmonary fibrosis or TGF-ß1 stimulation in vitro, macrophages exhibited an M2-polarized phenotype and secreted more CXCL16 than those of the control group. Moreover, flow cytometry revealed increased expression levels of CD69 and CXCR6 in pulmonary CD4 T cells during fibrosis progression. The administration of bortezomib alleviated bleomycin-induced pulmonary fibrosis, accompanied by reduced ratio of M2-polarized macrophages and decreased accumulation of CD4 T cells expressing CXCR6. CONCLUSIONS: Our findings provide insights into the key immune players involved in bleomycin-induced pulmonary fibrosis and offer preclinical evidence supporting the repurposing strategy and combination approaches to reduce lung fibrosis.

Effects of micro- and nano-plastics on growth, antioxidant system, DMS, and DMSP production in Emiliania huxleyi.

Due to the potential impacts of microplastics (MPs) and nanoplastics (NPs) on algal growth and thereby affect the climate-relevant substances, dimethylsulfoniopropionate (DMSP) and dimethyl sulfide (DMS), we studied the polystyrene (PS) MPs and NPs of 1 µm and 80 nm impacts on the growth, chlorophyll content, reactive oxygen species (ROS), antioxidant enzyme activity, and DMS/DMSP production in Emiliania huxleyi. E. huxleyi is a prominent oceanic alga that plays a key role in DMS and DMSP production. The results revealed that high concentrations of MPs and NPs inhibited the growth, carotenoid (Car), and Chl a concentrations of E. huxleyi. However, short-time exposure to low concentrations of PS MPs and NPs stimulated the growth of E. huxleyi. Furthermore, high concentrations of MPs and NPs resulted in an increase in the superoxide anion radical (O2.-) production rate and a decrease in the malondialdehyde (MDA) content compared with the low concentrations. Exposure to MPs and NPs at 5 mg L-1 induced superoxide dismutase (SOD) activity as a response to scavenging ROS. High concentrations of MPs and NPs significantly inhibited the production of DMSP and DMS. The findings of this study support the potential ecotoxicological impacts of MPs and NPs on algal growth, antioxidant system, and dimethylated sulfur compounds production, which maybe potentially impact the global climate.

Historical and contemporary applications of moxibustion at Gaohuang (BL 43). / 膏肓灸古今应用探析.

The relevant passages on moxibustion at Gaohuang (BL 43) in the Chinese Medical Code (fifth edition), and relevant literature on moxibustion at Gaohuang (BL 43) published up to January 17th, 2023 in the CNKI, Wanfang, VIP, SinoMed, PubMed, Web of Science, EMbase and Scopus were searched. The localization and selection methods of Gaohuang (BL 43), types of moxibustion at Gaohuang (BL 43), moxibustion quantity, and the main clinical indications were analyzed. As a result, a total of 227 ancient passages were included, with 51 related to moxibustion quantity and 171 related to clinical indications, encompassing 33 different diseases. A total of 50 modern articles were reviewed, covering 26 different diseases. The key of selection methods of Gaohuang (BL 43) is exploring sensitivity around the scapula, with direct moxibustion as a preferred technique; the optimal moxibustion dose is detenuined by arrival and withdrawal of deqi, and primary indications were related to syndrome of heart and lung deficiencies.

Structure and Functions of Endophytic Bacterial Communities Associated with Sphagnum Mosses and Their Drivers in Two Different Nutrient Types of Peatlands.

Sphagnum mosses are keystone plant species in the peatland ecosystems that play a crucial role in the formation of peat, which shelters a broad diversity of endophytic bacteria with important ecological functions. In particular, methanotrophic and nitrogen-fixing endophytic bacteria benefit Sphagnum moss hosts by providing both carbon and nitrogen. However, the composition and abundance of endophytic bacteria from different species of Sphagnum moss in peatlands of different nutrient statuses and their drivers remain unclear. This study used 16S rRNA gene amplicon sequencing to examine endophytic bacterial communities in Sphagnum mosses and measured the activity of methanotrophic microbial by the 13C-CH4 oxidation rate. According to the results, the endophytic bacterial community structure varied among Sphagnum moss species and Sphagnum capillifolium had the highest endophytic bacterial alpha diversity. Moreover, chlorophyll, phenol oxidase, carbon contents, and water retention capacity strongly shaped the communities of endophytic bacteria. Finally, Sphagnum palustre in Hani (SP) had a higher methane oxidation rate than S. palustre in Taishanmiao. This result is associated with the higher average relative abundance of Methyloferula an obligate methanotroph in SP. In summary, this work highlights the effects of Sphagnum moss characteristics on the endophytic bacteriome. The endophytic bacteriome is important for Sphagnum moss productivity, as well as for carbon and nitrogen cycles in Sphagnum moss peatlands.

Investigation on the construction of teaching case base in medical genetics.

Medical genetics is a basic medical course that discusses the diagnosis, prevention and treatment of diseases in relation with genetic factors. This course requires students who have abilities of strong logical thinking, independent thinking, problem analyzing and solving. Single "cramming" teaching is difficult to mobilize students' autonomous learning, and hardly achieves teaching effect of medical genetics. Teaching of case-based discussion breaks passive teaching mode in traditional class. The teacher throws out typically clinical cases. The students prepare materials around relevant problems of cases, and carry out class discussion. Then, key and difficult points of the course are integrated in teaching and learning interaction, which reaches a remarkable effect of teaching. Since 2013, the teaching and research group has carried out teaching of case-based discussion in undergraduates majoring in clinical medicine. In this paper, we screen and sort clinical cases on the basis of course teaching plan and case-based discussion in the teaching of medical genetics. The cases are summarized into 8 chapters in teaching case base, which basically cover the teaching of disease genetics and clinical genetics.The construction of teaching case base in medical genetics has realized the deep integration of clinical cases and teaching. Students can understand and master important and difficult points of teaching in a more intuitive way, which is helpful to stimulate students' innovative thinking, improve students' learning interest and class participation.

Barriers and facilitators to offering post-intensive care follow-up services from the perspective of critical care professionals: A qualitative study.

BACKGROUND: Various programmes and models for post-intensive care unit (ICU) follow-up services have been developed worldwide. In China, post-ICU follow-up remains in the exploratory stage and little is known regarding the appropriate form and challenges of implementation, which need to be further explored. AIM: This study aimed to explore and describe the barriers to and facilitators of post-ICU follow-up services from the perspective of critical care professionals. DESIGN: This was a descriptive qualitative study. Semi-structured interviews were conducted with 21 health care workers whose units had offered ICU survivors different forms of follow-up services; the data were analysed by qualitative content analysis during August 2022 and December 2022. SETTING: The study was conducted at 14 ICUs in 11 tertiary hospitals in Shanghai, China. FINDINGS: Seventeen subthemes were extracted as barriers and facilitators in the follow-up of ICU survivors. In the initiating process, the barriers included the restriction of decision-making rights and scope of practice, indifferent attitude towards survivors and repeated work. The facilitators included admitted significance, the needs of ICU survivors, the conscientiousness of professionals and the pioneers and leadership support. In the implementation process, lack of confidence, lack of cooperation in medical consortium, distrusted relationships, restrictions of medical insurance, ageing problems and insufficient human resources acted as barriers, whereas lessons learned, positive feedback and digital support served as facilitators. Furthermore, recommendations and tips were identified for offering follow-up services. CONCLUSION: Medical personnel can better utilize available resources and develop strategies to overcome constraints by gaining insights into the abovementioned barriers and facilitators. The findings of this study can provide a useful reference for structured and systematic follow-ups to ameliorate post-intensive care syndrome in low- and middle-income countries. RELEVANCE TO CLINICAL PRACTICE: Publicity and educational measures play a crucial role in enhancing the awareness of survivors and the consensus of health care professionals from medical consortium regarding impairments after critical care. Leadership and policy support can address numerous obstacles to guiding follow-up services.

Preparation of NaYF4:Tm, Yb, and Gd Luminescent Nanorods/SiO2 Nanospheres Composite Thin Film and Its Application in Perovskite Solar Cells.

In this study, we aim to minimize light loss and achieve high power conversion efficiencies (PCE) in perovskite solar cells (PSCs) by employing a spectral conversion film component with antireflection properties. In our scheme, NaYF4:Tm, Yb, and Gd luminescent nanorod/silica nanosphere-based thin films are applied on CH3NH3PbI3 PSCs to improve the device efficiency. The film was fabricated by spin coating an aged silica sol containing NaYF4:Tm, Yb, and Gd luminescent nanorods. The size and the spectral conversion properties of the NaYF4:Tm, Yb, and Gd luminescent nanorods were controlled by tuning the Gd3+ ion concentration. The microstructure and the transmittance properties of the thin film were controlled by changing the concentration of NaYF4:Tm, Yb, and Gd luminescent nanorod in silica sol. The thin films have excellent spectral conversion properties while exhibiting a maximum transmittance. The photovoltaic performance of PSCs with NaYF4:Tm, Yb, and Gd luminescent nanorod/silica nanosphere-based thin films was systematically investigated. The light transmittance was optimized to 95.1% on a cleaned glass substrate, which resulted in an average increase of about 3.0% across the broadband range of 400-800 nm. The optimized films widen the spectrum of light absorbed by conventional PSC cells and reduce reflections across a broad range, enhancing the photovoltaic performance of PSCs. As a result, the PCE of the PSC increased from 14.51% for the reference device without a thin film to 15.67% for the PSC device with an optimized thin film. This study presents a comprehensive solution to the problem of Fresnel reflection and spectral response mismatch of the PSCs, which provides new ideas for the light management of PSCs.

HuR-induced circ_0082319 contributes to hepatocellular carcinoma by elevating PTK2 through miR-505-3p.

The aim of the present research is to explore the biological function and mechanism of circ_0082319 in HCC progression. Circ_0082319, microRNA-505-3p (miR-505-3p), protein tyrosine kinase 2 (PTK2), and human antigen R (HuR, also known as ELAVL1) level were detected by real-time quantitative polymerase chain reaction. Cell viability, proliferation, apoptosis, invasion, and angiogenesis were measured using (4-5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, 5-ethynyl-2'-deoxyuridine (EdU), flow cytometry, transwell, and tube formation assays. Protein levels of c-Myc, MMP2, PTK2, and HuR were examined using western blot. The glycolysis levels were assessed using specific kits. Binding between miR-505-3p and circ_0082319 or PTK2 was predicted by Starbase and verified by a dual-luciferase reporter and RNA immunoprecipitation assays. The biological role of circ_0082319 on HCC tumor growth was examined using xenograft tumor model in vivo. Circ_0082319, PTK2, and HuR were highly expressed, and miR-505-3p was reduced in HCC samples and cell lines. Moreover, the knockdown of circ_0082319 might repress HCC cell proliferation, invasion, angiogenesis, and induce apoptosis in vitro. In mechanism, circ_0082319 served as a sponge of miR-505-3p to regulate PTK2 expression. HuR expedited circ_0082319 expression in HCC cells. HuR-mediated circ_0082319 might accelerate HCC cell proliferation, invasion, angiogenesis, and suppress apoptosis by the miR-505-3p/PTK2 axis, hinting at a promising therapeutic target for HCC treatment.

Magnetic-responsive solid acid catalysts for esterification.

Two kinds of magnetic-responsive solid acid catalysts were designed and prepared via an in situ polymerization of poly(ionic liquid)s (PILs) on the surface of Fe3O4@SiO2 NPs for the catalyzed esterification of palmitic acid and methanol. They were characterized using XRD, TGA, VSM, NMR spectroscopy, FTIR spectroscopy, XPS, SEM, and GC techniques. The results confirmed the preparation of solid acid catalysts. Meanwhile, they possessed excellent catalytic activity and recyclability. The effect of the reaction conditions on the esterification was investigated through single-factor analyses, and the proposed catalytic mechanism of the prepared solid acid catalysts in the esterification are also discussed. Under the optimal reaction conditions (10 wt% catalyst, 6 h, 70 °C, and molar ratio (MR) of methanol to palmitic acid of 12 : 1), the conversion rate of palmitic acid could reach 94% and 79% with Fe3O4@SiO2-poly(1-vinyl-3-ethylimidazolium phosphotungstate) (Fe3O4@SiO2-P([VLIM]PW)) and Fe3O4@SiO2-poly(1-vinylimidazole-3-propyl sulfonate) (Fe3O4@SiO2-P([VLIM]SO3)) NPs serving as catalysts, respectively. Furthermore, the Fe3O4@SiO2-P([VLIM]PW) NPs could still maintain a high catalytic activity even after being reused 5 times without significant deactivation.

[Effects of electroacupuncture on the secretion function of ovarian cells and kisspeptin/kiss1r system in rats with polycystic ovarian syndrome].

OBJECTIVE: To observe the effects of electroacupuncture （EA） on hormone secretion function of ovarian granulosa cells and theca cells, as well as the expression changes of kisspeptin and kiss1r in rats with polycystic ovarian syndrome （PCOS）, so as to explore the mechanism of EA for relieving ovarian dysfunction in PCOS rats. METHODS: Forty-eight SD female rats were randomly divided into control group, model group, EA group and flutamide group, with 12 rats in each group. PCOS rat model was replicated with the gavage of letrozole （0.1 mg/mL, 10 mL•kg-1•d-1）. In the EA group, EA （2 Hz, 2 mA） was used to stimulate "Guanyuan" （CV4） for 20 min each time. In the flutamide group, flutamide solution （50 mg•kg-1•d-1） was administrated by gavage. The treatments were given once daily for 14 days in each group. After the modeling and treatment, the body and ovarian weights of the rats were measured, and the ovarian index was calculated. Using HE staining, the morphological changes of ovary were observed. ELISA was adopted to detect the contents of testosterone （T）, luteinizing hormone （LH） and estradiol （E2） in serum, the contents of E2 and T in the culture medium of ovarian granulosa cells and theca cells, as well as the content of kisspeptin in the ovarian tissue. The positive expression of kisspeptin in ovary was observed by immunohistochemical method, and the protein expression of its receptor kiss1r was detected by Western blot. RESULTS: Compared with the control group, the body and ovarian weights, ovarian index, the contents of T and LH in serum and that of T in the culture medium of theca cells, as well as the content and positive expression of kisspeptin in ovary were all increased （P<0.01, P<0.05）； and the content of E2 in the culture medium of granulosa cells was decreased （P<0.01） in the model group. When compared with the model group, in the EA and flutamide groups, the body and ovarian weights, ovarian index, the contents of T and LH in serum and that of T in the culture medium of theca cells, as well as the content and expression of kisspeptin in ovary were all decreased （P<0.01, P<0.05）； and the content of E2 in the culture medium of granulosa cells was increased （P<0.05, P<0.01）. CONCLUSION: EA regulates the serum sex hormone levels, the secretion function of the ovarian granulosa cells and theca cells, and the ovarian kisspeptin/kiss1r protein expression in PCOS rats, showing the similar effect as receptor blockade intervention. It is suggested that the improvement of EA in ovarian dysfunction of PCOS rats may be related to the kisspeptin/kiss1r system.

Bioactive diterpenoids isolated from the twigs and leaves of Casearia velutina.

Nine previously undescribed clerodane-type diterpenoids (1-9), named caseabalanspenes A-I, along with six know compounds (10-15), were isolated from the twigs and leaves of Casearia velutina. Spectroscopic data (1D and 2D NMR) analysis permitted the definition of their structures and then determination of the molecular formula of the compound by high resolution mass spectrometry (HR-ESI-MS). It is worth noting that compound 7 contains N- heterocycle. Compounds 1-8 were tested the anti-inflammasome activity, and compound 3 exhibited potent activity and decreased LDH level in a dose-dependent manner, with IC50 values of 2.90 µM.

Glycolic acid-based deep eutectic solvents boosting co-production of xylo-oligomers and fermentable sugars from corncob and the related kinetic mechanism.

BACKGROUND: Xylo-oligomers are a kind of high value-added products in biomass fractionation. Although there are several chemical methods to obtain xylo-oligomers from biomass, the reports about the deep eutectic solvents (DESs)-mediated co-production of xylo-oligomers and fermentable sugars and the related kinetic mechanism are limited. RESULTS: In this work, glycolic acid-based DESs were used to obtain xylo-oligomers from corncob. The highest xylo-oligomers yield of 65.9% was achieved at 120 °C for 20 min, of which the functional xylo-oligosaccharides (XOSs, DP 2-5) accounted for up to 31.8%. Meanwhile, the enzymatic digestion of cellulose and xylan in residues reached 81.0% and 95.5%, respectively. Moreover, the addition of metal inorganic salts significantly accelerated the hydrolysis of xylan and even the degradation of xylo-oligomers in DES, thus resulting in higher selectivity of xylan removal. AlCl3 showed the strongest synergistic effect with DES on accelerating the processes, while FeCl2 is best one for xylo-oligomers accumulation, affording the highest xylo-oligomers yield of 66.1% for only 10 min. Furthermore, the kinetic study indicates that the 'potential hydrolysis degree' model could well describe the xylan hydrolysis processes and glycolic acid/lactic acid (3:1) is a promising solvent for xylo-oligomers production, in particular, it worked well with FeCl2 for the excellent accumulation of xylo-oligomers. CONCLUSIONS: Glycolic acid-based deep eutectic solvents can be successfully applied in corncob fractionation with excellent xylo-oligomers and fermentable sugars yields on mild conditions, and the large amount of xylo-oligosaccharides accumulation could be achieved by specific process controlling. The strategies established here can be useful for developing high-valued products from biomass.

Variations in the archaeal community and associated methanogenesis in peat profiles of three typical peatland types in China.

BACKGROUND: Peatlands contain about 500 Pg of carbon worldwide and play a dual role as both a carbon sink and an important methane (CH4) source, thereby potentially influencing climate change. However, systematic studies on peat properties, microorganisms, methanogenesis, and their interrelations in peatlands remain limited, especially in China. Therefore, the present study aims to investigate the physicochemical properties, archaeal community, and predominant methanogenesis pathways in three typical peatlands in China, namely Hani (H), Taishanmiao (T), and Ruokeba (R) peatlands, and quantitively determine their CH4 production potentials. RESULTS: These peatlands exhibited high water content (WC) and total carbon content (TC), as well as low pH values. In addition, R exhibited a lower dissolved organic carbon concentration (DOC), as well as higher total iron content (TFe) and pH values compared to those observed in T. There were also clear differences in the archaeal community between the three peatlands, especially in the deep peat layers. The average relative abundance of the total methanogens ranged from 10 to 12%, of which Methanosarcinales and Methanomicrobiales were the most abundant in peat samples (8%). In contrast, Methanobacteriales were mainly distributed in the upper peat layer (0-40 cm). Besides methanogens, Marine Benthic Group D/Deep-Sea Hydrothermal Vent Euryarchaeotic Group 1 (MBG-D/DHVEG-1), Nitrosotaleales, and several other orders of Bathyarchaeota also exhibited high relative abundances, especially in T. This finding might be due to the unique geological conditions, suggesting high archaeal diversity in peatlands. In addition, the highest and lowest CH4 production potentials were 2.38 and 0.22 µg g-1 d-1 in H and R, respectively. The distributions of the dominant methanogens were consistent with the respective methanogenesis pathways in the three peatlands. The pH, DOC, and WC were strongly correlated with CH4 production potentials. However, no relationship was found between CH4 production potential and methanogens, suggesting that CH4 production in peatlands may not be controlled by the relative abundance of methanogens. CONCLUSIONS: The results of the present study provide further insights into CH4 production in peatlands in China, highlighting the importance of the archaeal community and peat physicochemical properties for studies on methanogenesis in distinct types of peatlands.

Solid-Phase Polymerization Using Anion-Exchange Resin Can Almost Completely Crosslink Hemoglobin to Prepare Hemoglobin-Based Oxygen Carriers.

Introduction: A limitation of hemoglobin-based oxygen carriers (HBOCs) as oxygen therapeutics is unpolymerized hemoglobin, which induces vasoconstriction leading to hypertension. The removal of unpolymerized hemoglobin from polymerized hemoglobin (PolyHb) is complex, expensive, and time-consuming. Methods: Herein, we developed a method to completely polymerize hemoglobin almost without unpolymerized hemoglobin. Hemoglobin was adsorbed on the anion-exchange resin Q Sepharose Fast Flow or DEAE Sepharose Fast Flow, and acetal, a crosslinker prepared from glutaraldehyde and ethylene glycol, was employed to polymerize the hemoglobin. The polymerization conditions, including reaction time, pH, resin type, and molar ratios of glutaraldehyde to ethylene glycol and hemoglobin to acetal, were optimized. The blood pressure and blood gas of mice injected with PolyHb were monitored as well. Results: The optimal polymerization condition of PolyHb was when the molar ratio of glutaraldehyde to ethylene glycol was 1:20, and the molar ratio of 10 mg/mL hemoglobin adsorbed on anion-exchange resin to glutaraldehyde was 1:300 for 60 min. Under optimized reactive conditions, hemoglobin was almost completely polymerized, with <1% hemoglobin remaining unpolymerized, and the molecular weight of PolyHb was more centrally distributed. Furthermore, hypertension was not induced in mice by PolyHb, and there were also no pathological changes observed in arterial oxygen, blood gas, electrolytes, and some metabolic indicators. Conclusion: The findings of this study indicate that the use of solid-phase polymerization and acetal is a highly effective and innovative approach to HBOCs, resulting in the almost completely polymerized hemoglobin. These results offer promising implications for the development of new methods for preparing HBOCs.

The Gut Microbiota-Brain Axis: Potential Mechanism of Drug Addiction.

As a chronic encephalopathy, drug addiction is responsible for millions of deaths per year around the world. The gut microbiome is a crucial component of the human microbiome. Through dynamic bidirectional communication along the 'gut-brain axis,' gut bacteria cooperate with their hosts to regulate the development and function of the immune, metabolic, and nervous systems. These processes may affect human health because some brain diseases are related to the composition of gut bacteria, and disruptions in microbial communities have been implicated in neurological disorders. We review the compositional and functional diversity of the gut microbiome in drug addiction. We discuss intricate and crucial connections between the gut microbiota and the brain involving multiple biological systems and possible contributions by the gut microbiota to neurological disorders. Finally, the treatment of probiotics and fecal transplantation was summarized. This was done to further understand the role of intestinal microecology in the pathogenesis of drug addiction and to explore new methods for the treatment of drug addiction.

Strophioblachins A-K, Structurally Intriguing Diterpenoids from Strophioblachia fimbricalyx with Potential Anticardiac Hypertrophic Inhibitory Activity.

Three new rearranged diterpenoids, strophioblachins A-C (1-3), eight new diterpenoids, strophioblachins D-K (4-11), and seven previously described diterpenoids (12-18) were purified from the aerial parts of Strophioblachia fimbricalyx. Compounds 1 and 2 contain a rare 6/6/5/6 ring system, while 3 has an uncommon tricyclo[4.4.0.08,9]tridecane-bridged unit, and their diterpenoid skeletons are being reported for the first time. Utilizing spectroscopic and HRESIMS data analysis, the structures of the new compounds (1-11) were established, and ECD and 13C NMR calculations were used to confirm the relative and absolute configurations of 11 and 9. The absolute configurations of compounds 1, 3, and 10 were established using single-crystal X-ray diffraction. The results of testing for anticardiac hypertrophic activity demonstrated that compounds 10 and 15 dose-dependently lowered the mRNA expression of Nppa and Nppb. Protein levels were confirmed by Western blotting, which also demonstrated that compounds 10 and 15 lowered the expression of the hypertrophic marker ANP. The cytotoxic activity against neonatal rat cardiomyocytes was assayed in vitro by the CCK-8 and ELISA methods, and the results showed that compounds 10 and 15 were only very weakly active in the range.

Development of an mRNA vaccine against a panel of heterologous H1N1 seasonal influenza viruses using a consensus hemagglutinin sequence.

Seasonal influenza, causes hundreds of thousands of deaths annually, posing a severe threat to human health. Currently available influenza vaccines are targeted only at specific strains or conserved epitopes; however, these vaccines are not completely efficacious because influenza viruses can undergo mutation during circulation, leading to antigenic mismatch between recommended strains and circulating strains and elusion from the immune system. Therefore, developing an influenza vaccine that is quick, effective, and broadly protective has become crucial, and the integral part of hemagglutinin (HA) remains an ideal target for vaccine development. This study developed a lipid nanoparticle-encapsulated nucleoside-modified mRNA vaccine (mRNA-LNPs) encoding a consensus full-length HA sequence (H1c) and evaluated its protective efficacy and immunogenicity through in vitro and in vivo assays. Following two intramuscular immunizations (2, 10 µg, or 20 µg) at a 3-week interval in BALB/c mice, H1c-mRNA-LNP vaccine induced strong antibodies as shown in the hemagglutination-inhibition test and protective neutralizing antibodies against numerous heterologous H1N1 influenza viruses as shown in the microneutralization assay. Additionally, both Th1- and Th2-biased cellular immune responses were elicited, with the Th1-biased response being stronger. Two doses of the H1c-mRNA-LNP vaccine could neutralize a panel of heterologous H1N1 influenza viruses and could confer protection in mice. Taken together, these findings suggest that the H1c-mRNA-LNP vaccine encoding a consensus full-length HA is a feasible strategy for developing a cross-protective vaccine against a panel of heterologous H1N1 influenza viruses.

Biosynthetic Enzyme-guided Disease Correlation Connects Gut Microbial Metabolites Sulfonolipids to Inflammatory Bowel Disease Involving TLR4 Signaling.

The trillions of microorganisms inhabiting the human gut are intricately linked to human health. At the species abundance level, correlational studies have connected specific bacterial taxa to various diseases. While the abundances of these bacteria in the gut serve as good indicators for disease progression, understanding the functional metabolites they produce is critical to decipher how these microbes influence human health. Here, we report a unique biosynthetic enzyme-guided disease correlation approach to uncover microbial functional metabolites as potential molecular mechanisms in human health. We directly connect the expression of gut microbial sulfonolipid (SoL) biosynthetic enzymes to inflammatory bowel disease (IBD) in patients, revealing a negative correlation. This correlation is then corroborated by targeted metabolomics, identifying that SoLs abundance is significantly decreased in IBD patient samples. We experimentally validate our analysis in a mouse model of IBD, showing that SoLs production is indeed decreased while inflammatory markers are increased in diseased mice. In support of this connection, we apply bioactive molecular networking to show that SoLs consistently contribute to the immunoregulatory activity of SoL-producing human microbes. We further reveal that sulfobacins A and B, two representative SoLs, primarily target Toll-like receptor 4 (TLR4) to mediate immunomodulatory activity through blocking TLR4's natural ligand lipopolysaccharide (LPS) binding to myeloid differentiation factor 2, leading to significant suppression of LPS-induced inflammation and macrophage M1 polarization. Together, these results suggest that SoLs mediate a protective effect against IBD through TLR4 signaling and showcase a widely applicable biosynthetic enzyme-guided disease correlation approach to directly link the biosynthesis of gut microbial functional metabolites to human health.

Refactoring and Heterologous Expression of Class III Lanthipeptide Biosynthetic Gene Clusters Lead to the Discovery of N,N-Dimethylated Lantibiotics from Firmicutes.

Class III lanthipeptides are an emerging subclass of lanthipeptides, representing an underexplored trove of new natural products with potentially broad chemical diversity and important biological activity. Bioinformatic analysis of class III lanthipeptide biosynthetic gene cluster (BGC) distribution has revealed their high abundance in the phylum Firmicutes. Many of these clusters also feature methyltransferase (MT) genes, which likely encode uncommon class III lanthipeptides. However, two hurdles, silent BGCs and low-yielding pathways, have hindered the discovery of class III lanthipeptides from Firmicutes. Here, we report the design and construction of a biosynthetic pathway refactoring and heterologous overexpression strategy which seeks to overcome these hurdles, simultaneously activating and increasing the production of these Firmicutes class III lanthipeptides. Applying our strategy to MT-containing BGCs, we report the discovery of new class III lanthipeptides from Firmicutes bearing rare N,N-dimethylations. We reveal the importance of the first two amino acids in the N-terminus of the core peptide in controlling the MT dimethylation activity. Leveraging this feature, we engineer class III lanthipeptides to enable N,N-dimethylation, resulting in significantly increased antibacterial activity. Furthermore, the refactoring and heterologous overexpression strategy showcased in this study is potentially applicable to other ribosomally synthesized and post-translationally modified peptide BGCs from Firmicutes, unlocking the genetic potential of Firmicutes for producing peptide natural products.