A cross-sectional investigation of factors influencing mpox vaccine hesitancy for students in Southwest China.

From July to September 2023, China reported over 1, 400 confirmed cases of mpox transmitted mainly through sexual contact between males. Meanwhile, the percentage of men who have sex with men at universities in southwestern China is increasing every year, which is likely to lead to a potential spread of mpox on campuses. Vaccination is an effective preventive measure against infectious diseases, this study examined the willingness of university students in Southwest China to receive the mpox vaccine and analyzed the factors influencing their decision. A cross-sectional survey was conducted among 7311 university students from 10 universities in Southwest China between August 13 and September 1, 2023. The survey revealed a hesitancy rate of 56.13% toward the mpox vaccine, with the most common reason being concerns about vaccine safety (1407/4104, 34.29%). Univariate analysis identified 13 variables that significantly differed between the vaccine acceptance and vaccine hesitancy groups. Multivariate logistic regression analyses indicated protective factors for vaccine hesitancy, such as sexually transmitted diseases, previous knowledge about mpox, frequent information about mpox, people can get reinfection of mpox, and worries about mpox endemic in China. Additionally, the confidence and convenience dimensions in the 3Cs model were identified as risk factors for mpox vaccine hesitancy. This study found a high rate of vaccine hesitancy among university students in Southwest China regarding the mpox vaccine. Collaboration between university and healthcare departments is recommended to address mpox vaccine hesitancy among college students, thereby promoting their willingness to receive the mpox vaccine.

Breakthrough infection and reinfection in patients with mpox.

Recently, patients with Mpox breakthrough infection or reinfection were constantly reported. However, the induction, risk factors, and important clinical symptoms of breakthrough infection and reinfection of Mpox virus (MPXV), as well as the factors affecting the effectiveness of Mpox vaccine are not characterized. Herein, a literature review was preformed to summarize the risk factors and important clinical symptoms of patients with Mpox breakthrough infection or reinfection, as well as the factors affecting the effectiveness of smallpox vaccine against Mpox. Results showed that MSM sexual behavior, condomless sexual behavior, multiple sexual partners, close contact, HIV infection, and the presence of comorbidity are important risk factors for Mpox breakthrough infection and reinfection. Genital ulcers, proctitis, and lymphadenopathy are the important clinical symptoms of Mpox breakthrough infection and reinfection. The effectiveness of emergent vaccination of smallpox vaccine for post-exposure of MPXV is associated with smallpox vaccination history, interval between exposure and vaccination, and history of HIV infection. This review provides a better understanding for the risk factors and important clinical symptoms of Mpox breakthrough infection and reinfection, as well as the formulation of Mpox vaccine vaccination strategies.

Evaluation and comparison of immune responses induced by two Mpox mRNA vaccine candidates in mice.

The epidemic of Mpox virus (MPXV) from May 2022 was once declared as a Public Health Emergency of International Concern by the World Health Organization. Vaccines play an important role in prevention of infectious diseases, and mRNA vaccine technology was proved to be a safe and effective platform with successful application in defense of coronavirus disease 2019. In this study, based on A29L, M1R, A35R, and B6R of MPXV, we developed two MPXV mRNA vaccine candidates, designated as MPXfus and MPXmix. The MPXfus was one-component, in which these four antigen proteins were linked in tandem by flexible linker and encoded by an individual mRNA as a fusion protein. The MPXmix was multicomponent containing four mRNA, and each mRNA encoded one antigen protein respectively. Mice were immunized with equal quality of MPXfus or MPXmix, delivered by lipid nanoparticles for evaluation and comparison of the immune responses induced by these two MPXV vaccine candidates. Results of immune response analyses indicated that both MPXfus and MPXmix could elicit high-level of antigen-specific antibodies and robust cellular immune response in mice. Moreover, results of virus neutralization assays suggested that sera from MPXfus- or MPXmix-immunized mice possessed high neutralizing activities against vaccinia virus. In addition, titers of antigen-specific antibody, levels of cellular immune response, and activities of neutralizing antibody against vaccinia virus induced by MPXfus and MPXmix presented no significant difference. In summary, this study provides valuable insights for further clinical development of one-component and multicomponent mRNA vaccine candidates for the prevention of MPXV and other orthomyxoviruses.

A Subunit Vaccine Candidate Composed of Mpox Virus A29L, M1R, A35R, and B6R Elicits Robust Immune Response in Mice.

With no specific antiviral drugs and preventive vaccines against Mpox virus (MPXV), the epidemic has led to the declaration of a Public Health Emergency of International Concern. As a developmental direction for new vaccines, studies of subunit vaccines based upon MPXV antigen proteins are lacking. In this study, A29L, M1R, A35R, and B6R of MPXV were expressed and purified from a prokaryotic system. The four MPXV antigen proteins in combination were mixed with aluminum hydroxide or CpG7909 as adjuvant, and subsequently used to inoculate mice. The results of enzyme-linked immunosorbent assay (ELISA), flow cytometry analyses, and enzyme-linked immunospot (ELISPOT) assays indicated that A29L, M1R, A35R, and B6R elicited high-level antigen-specific antibodies and CD4+ T cells-based cellular immune response in mice. Moreover, the results of virus neutralization assays suggested that sera from the mice immunized with four proteins elicited high neutralizing activities against the vaccinia virus. Notably, the results of ELISA, ELISPOT, and virus neutralization assays also showed that the CpG7909 adjuvant was more effective in inducing an immune response compared with the aluminum adjuvant. In summary, this study offers valuable insights for further studies of subunit vaccine candidates for the prevention of MPXV and other orthomyxoviruses.

BMI1 fine-tunes gene repression and activation to safeguard undifferentiated spermatogonia fate.

Introduction: Spermatogenesis is sustained by the homeostasis of self-renewal and differentiation of undifferentiated spermatogonia throughout life, which is regulated by transcriptional and posttranscriptional mechanisms. B cell-specific Moloney murine leukemia virus integration site 1 (BMI1), one of spermatogonial stem cell markers, is a member of Polycomb repressive complex 1 (PRC1) and important to spermatogenesis. However, the mechanistic underpinnings of how BMI1 regulates spermatogonia fate remain elusive. Methods: We knocked down BMI1 by siRNA to investigate the role of BMI1 in undifferentiated spermatogonia. Differentially expressed genes were identified by RNA-seq and used for KEGG pathway analysis. We performed ChIP-seq analysis in wild type and BMI1 knockdown cells to explore the underlying molecular mechanisms exerted by BMI1. BMI1-associated alterations in repressive histone modifications were detected via Western blotting and ChIP-seq. Furthermore, we performed mass spectrometry and Co-immunoprecipitation assays to investigate BMI1 co-factors. Finally, we demonstrated the genomic regions occupied by both BMI1 and its co-factor. Results: BMI1 is required for undifferentiated spermatogonia maintenance by both repressing and activating target genes. BMI1 preserves PI3K-Akt signaling pathway for spermatogonia proliferation. Decrease of BMI1 affects the deposition of repressive histone modifications H2AK119ub1 and H3K27me3. BMI also positively regulates H3K27ac deposited genes which are associated with proliferation. Moreover, we demonstrate that BMI1 interacts with Sal-like 4 (SALL4), the transcription factor critical for spermatogonia function, to co-regulate gene expression. Discussion: Overall, our study reveals that BMI1 safeguards undifferentiated spermatogonia fate through multi-functional roles in regulating gene expression programs of undifferentiated spermatogonia.

Generation of a DNA-launched classical swine fever virus infectious clone packaged in bacterial artificial chromosome.

Reverse genetics system offers powerful tool for the research of RNA viruses. The infectious clones of classical swine fever virus (CSFV) were commonly constructed either in high- or low-copy number plasmids and transcribed to infectious RNA using phage RNA-polymerases. Herein, the full-length genome of CSFV Shimen strain, flanked by cytomegalovirus immediate-early (CMV) promoter (a eukaryotic RNA polymerase II promoter) sequence at the 5'-end and the hepatitis delta virus ribozyme along with the bovine growth hormone termination and polyadenylation signal sequences at the 3'-end, was packaged in bacterial artificial chromosome vector to establish a CSFV infectious clone pBAC-smCSFV. This infectious cDNA clone maintained stability after passaged 20 times in bacteria. Transfection of PK15 cells with this cDNA clone facilitated recovery of infectious progeny virus which was identical to parent virus as characterized by RT-qPCR, western blotting, indirect immunofluorescence assay, one-step growth kinetics analysis and nucleotide sequencing. Based on this CSFV infectious cDNA clone, the mCherry was inserted between viral Npro and C protein to develop reporter virus CSFV-mCherry. The mCherry was stably expressed after CSFV-mCherry was passaged 10 times in PK15 cells. Taken together, this present study develops a concise and efficient CSFV infectious cDNA clone and a reporter virus CSFV-mCherry. To the best of our knowledge, this is the first combination of CMV promoter and BAC system in construction of CSFV reverse genetics system. The CSFV infectious cDNA clone and the reporter virus will be useful in the study of CSFV virus biology, virulence determinants, molecular pathogenesis, vaccine development and virus-host interaction.

2cChIP-seq and 2cMeDIP-seq: The Carrier-Assisted Methods for Epigenomic Profiling of Small Cell Numbers or Single Cells.

Chromatin immunoprecipitation coupled with high-throughput sequencing (ChIP-seq) can profile genome-wide epigenetic marks associated with regulatory genomic elements. However, conventional ChIP-seq is challenging when examining limited numbers of cells. Here, we developed a new technique by supplementing carrier materials of both chemically modified mimics with epigenetic marks and dUTP-containing DNA fragments during conventional ChIP procedures (hereafter referred to as 2cChIP-seq), thus dramatically improving immunoprecipitation efficiency and reducing DNA loss of low-input ChIP-seq samples. Using this strategy, we generated high-quality epigenomic profiles of histone modifications or DNA methylation in 10-1000 cells. By introducing Tn5 transposase-assisted fragmentation, 2cChIP-seq reliably captured genomic regions with histone modification at the single-cell level in about 100 cells. Moreover, we characterized the methylome of 100 differentiated female germline stem cells (FGSCs) and observed a particular DNA methylation signature potentially involved in the differentiation of mouse germline stem cells. Hence, we provided a reliable and robust epigenomic profiling approach for small cell numbers and single cells.

Foxp1 controls brown/beige adipocyte differentiation and thermogenesis through regulating ß3-AR desensitization.

ß-Adrenergic receptor (ß-AR) signaling is a pathway controlling adaptive thermogenesis in brown or beige adipocytes. Here we investigate the biological roles of the transcription factor Foxp1 in brown/beige adipocyte differentiation and thermogenesis. Adipose-specific deletion of Foxp1 leads to an increase of brown adipose activity and browning program of white adipose tissues. The Foxp1-deficient mice show an augmented energy expenditure and are protected from diet-induced obesity and insulin resistance. Consistently, overexpression of Foxp1 in adipocytes impairs adaptive thermogenesis and promotes diet-induced obesity. A robust change in abundance of the ß3-adrenergic receptor (ß3-AR) is observed in brown/beige adipocytes from both lines of mice. Molecularly, Foxp1 directly represses ß3-AR transcription and regulates its desensitization behavior. Taken together, our findings reveal Foxp1 as a master transcriptional repressor of brown/beige adipocyte differentiation and thermogenesis, and provide an important clue for its targeting and treatment of obesity.

Classical swine fever virus Shimen infection increases p53 signaling to promote cell cycle arrest in porcine alveolar macrophages.

Classical swine fever virus (CSFV) replicates in macrophages and causes persistent infection. Despite its role in disastrous economic losses in swine industries, the molecular mechanisms underlying its pathogenesis are poorly understood. The virus evades the neutralizing immune response, subverting the immune system to ensure its own survival and persistence. Our genome-wide analysis of porcine alveolar macrophage transcriptional responses to CSFV Shimen infection using the Solexa/Illumina digital gene expression system revealed that p53 pathway components and cell cycle molecules were differentially regulated during infection compared to controls. Further, we investigated the molecular changes in macrophages infected with CSFV Shimen, focusing on the genes involved in the p53 pathway. CSFV Shimen infection led to phosphorylation and accumulation of p53 in a time-dependent manner. Furthermore, CSFV Shimen infection upregulated cyclin-dependent kinase inhibitor 1A (p21) mRNA and protein. In addition, CSFV Shimen infection induced cell cycle arrest at the G1 phase, as well as downregulation of cyclin E1 and cyclin-dependent kinase 2 (CDK2). The expression of genes in the p53 pathway did not change significantly after p53 knockdown by pifithrin-α during CSFV Shimen infection. Our data suggest that CSFV Shimen infection increases expression of host p53 and p21, and inhibits expression of cyclin E1 and CDK2, leading to cell cycle arrest at the G1 phase. CSFV may utilize this strategy to subvert the innate immune response and proliferate in host cells.

Caveolin-1-mediated endocytic pathway is involved in classical swine fever virus Shimen infection of porcine alveolar macrophages.

Macrophages are at the frontline of defense against pathogenic microorganisms. However, very little is known about the cell invasion mechanism of classical swine fever virus (CSFV) Shimen strain. To elucidate the infective mechanism of this important pathogen, we screened deep-sequencing data derived from macrophages infected with CSFV Shimen and uninfected macrophages, and identified a role of caveolin-1 (CAV1). Digital gene expression profiling showed that CAV1 was differentially expressed in CSFV Shimen-infected macrophages. Quantitative polymerase chain reaction and western blot analyses showed that the transcription and translation of CAV1 were significantly up-regulated in CSFV Shimen-infected macrophages. In addition, immunofluorescent confocal microscopy analysis suggested that CAV1 was temporally colocalized with CSFV E2 throughout the course of the infection. Through the overexpression of recombinant CAV1 or the silencing of CAV1 expression using small interfering RNA in macrophages, we demonstrated that CAV1 expression is beneficial for the replication of CSFV Shimen. However, RNA silencing of CAV1 did not prevent viral replication, which may indicate that CSFV can also enter macrophages by other mechanisms. Our findings suggest that CAV1-mediated endocytosis is advantageous for productive CSFV Shimen infection in macrophages, providing a new insight into the mechanisms of evasion of host immunity for successful viral infection.

Carbon Storage Patterns of Caragana korshinskii in Areas of Reduced Environmental Moisture on the Loess Plateau, China.

Precipitation patterns are influenced by climate change and profoundly alter the carbon sequestration potential of ecosystems. Carbon uptake by shrubbery alone accounts for approximately one-third of the total carbon sink; however, whether such uptake is altered by reduced precipitation is unclear. In this study, five experimental sites characterised by gradual reductions in precipitation from south to north across the Loess Plateau were used to evaluate the Caragana korshinskii's functional and physiological features, particularly its carbon fixation capacity, as well as the relationships among these features. We found the improved net CO2 assimilation rates and inhibited transpiration at the north leaf were caused by lower canopy stomatal conductance, which enhanced the instantaneous water use efficiency and promoted plant biomass as well as carbon accumulation. Regional-scale precipitation reductions over a certain range triggered a distinct increase in the shrub's organic carbon storage with an inevitable decrease in the soil's organic carbon storage. Our results confirm C. korshinskii is the optimal dominant species for the reconstruction of fragile dryland ecosystems. The patterns of organic carbon storage associated with this shrub occurred mostly in the soil at wetter sites, and in the branches and leaves at drier sites across the arid and semi-arid region.

Interactive response of photosynthetic characteristics in Haloxylon ammodendron and Hedysarum scoparium exposed to soil water and air vapor pressure deficits.

C4 plants possess better drought tolerance than C3 plants. However, Hedysarum scoparium, a C3 species, is dominant and widely distributed in the desert areas of northwestern China due to its strong drought tolerance. This study compared it with Haloxylon ammodendron, a C4 species, regarding the interactive effects of drought stress and different leaf-air vapor pressure deficits. Variables of interest included gas exchange, the activity levels of key C4 photosynthetic enzymes, and cellular anatomy. In both species, gas exchange parameters were more sensitive to high vapor pressure deficit than to strong water stress, and the net CO2 assimilation rate (An) was enhanced as vapor pressure deficits increased. A close relationship between An and stomatal conductance (gs) suggested that the species shared a similar response mechanism. In H. ammodendron, the activity levels of key C4 enzymes were higher, including those of phosphoenolpyruvate carboxylase (PEPC) and nicotinamide adenine dinucleotide phosphate-malate enzyme (NADP-ME), whereas in H. scoparium, the activity level of nicotinamide adenine dinucleotide-malate enzyme (NAD-ME) was higher. Meanwhile, H. scoparium utilized adaptive structural features, including a larger relative vessel area and a shorter distance from vein to stomata, which facilitated the movement of water. These findings implied that some C4 biochemical pathways were present in H. scoparium to respond to environmental challenges.