Comparative single-cell RNA sequencing analysis of immune response to inactivated vaccine and natural SARS-CoV-2 infection.

Uncovering the immune response to an inactivated SARS-CoV-2 vaccine (In-Vac) and natural infection is crucial for comprehending COVID-19 immunology. Here we conducted an integrated analysis of single-cell RNA sequencing (scRNA-seq) data from serial peripheral blood mononuclear cell (PBMC) samples derived from 12 individuals receiving In-Vac compared with those from COVID-19 patients. Our study reveals that In-Vac induces subtle immunological changes in PBMC, including cell proportions and transcriptomes, compared with profound changes for natural infection. In-Vac modestly upregulates IFN-α but downregulates NF-κB pathways, while natural infection triggers hyperactive IFN-α and NF-κB pathways. Both In-Vac and natural infection alter T/B cell receptor repertoires, but COVID-19 has more significant change in preferential VJ gene, indicating a vigorous immune response. Our study reveals distinct patterns of cellular communications, including a selective activation of IL-15RA/IL-15 receptor pathway after In-Vac boost, suggesting its potential role in enhancing In-Vac-induced immunity. Collectively, our study illuminates multifaceted immune responses to In-Vac and natural infection, providing insights for optimizing SARS-CoV-2 vaccine efficacy.

Identification of CYP46A1 as a new regulator of lipid metabolism through CRISPR-based whole-genome screening.

Abnormal lipid droplet (LD) metabolism causes a variety of disorders, especially to nonalcoholic fatty liver disease (NAFLD). But the mechanism of abnormal aggregation of LD is still not fully elucidated. Here, Genome-wide CRISPR-Cas9 knockout (GeCKO) screening was employed to identify candidate genes regulating LD metabolism in L02 cell. We analyzed simultaneously the transcriptomics of liver tissues of NAFLD to find potential genes involved in pathogenesis of NAFLD. After integration these data, we found that the expression of 43 candidate genes from the GeCKO screening was also decreased in tissues of NAFLD patients. Many of these 43 overlapping genes have been reported to play an important role in the formation of LD. Subsequently, we focused on CYP46A1, one of 43 candidate genes and mitochondria-related genes. We confirmed that the protein expression of CYP46A1 is deceased in tissues of NAFLD patients. Downregulation or overexpression of CYP46A1 affected LD accumulation in vitro. Deficiency of CYP46A1 impaired mitochondrial morphology and function, which may be responsible for the accumulation of LD. In summary, this study explored regulatory factors of LD accumulation at the whole-genome level, and demonstrated that CYP46A1 regulated LD formation involving in NAFLD pathogenesis. It provides new clues for studying the molecular mechanisms of diseases related to abnormal lipid metabolism.

Stimulation of PSTPIP1 to trigger proinflammatory responses in asymptomatic SARS-CoV-2 infections.

Background: A hyperinflammatory response to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection gravely worsens the clinical progression of coronavirus disease 2019 (COVID-19). Although the undesirable effects of inflammasome activation have been correlated to the severity of COVID-19, the mechanisms of this process in the asymptomatic infection and disease progression have not yet been clearly elucidated. Methods: We performed strand-specific RNA sequencing in 39 peripheral blood mononuclear cell (PBMC) samples from asymptomatic individuals（n = 10）, symptomatic patients（n = 16） and healthy donors（n = 13）. Results: Dysregulation of pyrin inflammasomes along with the proline-serine-threonine phosphatase-interacting protein 1 (PSTPIP1) gene was identified in SARS-COV-2 infection. Notably, the PSTPIP1 expression level showed a significant negative correlation with an adjacent long-noncoding RNA (lncRNA) RP11-797A18.6 in the asymptomatic individuals compared with the healthy controls. In addition, a decline in the nuclear factor kappa B subunit 1 (NFKB1) gene expression was observed in asymptomatic infection, followed by a rise in the mild and moderate disease stages, suggesting that altered NFKB1 expression and associated proinflammatory signals may trigger a disease progression. Conclusions: Overall, our results indicate that PSTPIP1-dependent pyrin inflammasomes-mediated pyroptosis and NF-κB activation might be potential preventive targets for COVID-19 disease development and progression.

Longitudinal change trend of the TCR repertoire reveals the immune response intensity of the inactivated COVID-19 vaccine.

Evidence concerning the individual differences in neutralizing antibody responses after receiving the COVID-19 vaccine remains lacking. In this study, we collected the serum and Peripheral blood mononuclear cells(PBMC) of 16 subjects who had never suffered from COVID-19 before during the course of two vaccine doses. Microneutralization assay is used to determine the immune response intensity of vaccine subjects. we revealed the change trend of TCR diversity using T cell receptor (TCR) sequencing. Then, we analyzed the correlation between HLA class II allele frequencies and the intensity of immune response. Finally, we identified several CDR3 sequences related to the intensity of the immune response. We analyzed the differences in D50 (DD50) between different time points, and found that there were two patterns in the change trend of TCR diversity, and the increased diversity group has stronger immune response. The inactivated vaccine is different from the mRNA vaccine against the spike protein, resulting in differences in TCR repertoire response patterns and antibody responses, which are related to HLA-DRB1 * 09:01. The presence of specific CDR3 sequences in the increased diversity group, rather than gene usage of the VJ gene, determines the intensity and persistence of neutralizing antibody titers. Finally, We identified the different response patterns of the human TCR repertoire to inactivated vaccines. The pattern with increased diversity is more likely to appear strong and more lasting immune response.

The biomarkers related to immune infiltration to predict distant metastasis in breast cancer patients.

Background: The development of distant metastasis (DM) results in poor prognosis of breast cancer (BC) patients, however, it is difficult to predict the risk of distant metastasis. Methods: Differentially expressed genes (DEGs) were screened out using GSE184717 and GSE183947. GSE20685 were randomly assigned to the training and the internal validation cohort. A signature was developed according to the results of univariate and multivariate Cox regression analysis, which was validated by using internal and external (GSE6532) validation cohort. Gene set enrichment analysis (GSEA) was used for functional analysis. Finally, a nomogram was constructed and calibration curves and concordance index (C-index) were compiled to determine predictive and discriminatory capacity. The clinical benefit of this nomogram was revealed by decision curve analysis (DCA). Finally, we explored the relationships between candidate genes and immune cell infiltration, and the possible mechanism. Results: A signature containing CD74 and TSPAN7 was developed according to the results of univariate and multivariate Cox regression analysis, which was validated by using internal and external (GSE6532) validation cohort. Mechanistically, the signature reflect the overall level of immune infiltration in tissues, especially myeloid immune cells. The expression of CD74 and TSPAN7 is heterogeneous, and the overexpression is positively correlated with the infiltration of myeloid immune cells. CD74 is mainly derived from myeloid immune cells and do not affect the proportion of CD8+T cells. Low expression levels of TSPAN7 is mainly caused by methylation modification in BC cells. This signature could act as an independent predictive factor in patients with BC (p = 0.01, HR = 0.63), and it has been validated in internal (p = 0.023, HR = 0.58) and external (p = 0.0065, HR = 0.67) cohort. Finally, we constructed an individualized prediction nomogram based on our signature. The model showed good discrimination in training, internal and external cohort, with a C-index of 0.742, 0.801, 0.695 respectively, and good calibration. DCA demonstrated that the prediction nomogram was clinically useful. Conclusion: A new immune infiltration related signature developed for predicting metastatic risk will improve the treatment and management of BC patients.

Garlic oil alleviates high triglyceride levels in alcohol-exposed rats by inhibiting liver oxidative stress and regulating the intestinal barrier and intestinal flora.

Garlic oil (GO) is a kind of natural extract extracted from garlic, which has strong antioxidant activity. This study elucidates the protective mechanism of GO against alcohol-induced high triglyceride levels. Sixty male Sprague Dawley rats were assigned to five groups, including a control group (CON), a model group (MOD) treated with alcohol 56% v/v at 8 ml kg-1 day-1 for 2 weeks then 10 ml kg-1 day-1 for 8 weeks, a low-dose GO group (GO-L) given GO at 20 mg kg-1 day-1, a high-dose GO group (GO-H) given GO at 40 mg kg-1 day-1, and a positive group (POS) given diammonium glycyrrhizinate at 200 mg kg-1 day-1. The results showed that GO could significantly reduce the serum and liver triglyceride levels caused by alcohol exposure (p < .05). The GO-H group significantly reduced MDA level, increased SOD and GSH-Px levels in serum, liver, and colon (p < .05), significantly increased the levels of Sirt1 and PGC-1α proteins and reduced FoxO1 protein level in liver (p < .05), and significantly increased the levels of ZO-1 and Claudin1 proteins in the colon compared to the MOD group (p < .05). The 16S rRNA sequencing showed that the intestinal flora of the GO-H group was significantly changed compared with the MOD group. In summary, GO has the potential to improve high triglyceride levels in serum and liver induced by alcohol exposure, which may be related to the inhibition of oxidative stress regulation of Sirt1 and its downstream proteins, and to the restoration of the intestinal barrier and intestinal flora.

Propolis Ameliorates Alcohol-Induced Depressive Symptoms in C57BL/6J Mice by Regulating Intestinal Mucosal Barrier Function and Inflammatory Reaction.

Accumulating evidence points to a critical role of the brain gut axis as an important paradigm for many central nervous system diseases. Recent studies suggest that propolis has obvious neuroprotective properties and functionality in regulating intestinal bacteria flora, hinting at a potential key effect at both terminals of this axis regulation. However, currently no clear evidence confirms the effects of propolis on alcohol-induced depression. Here, we establish an alcoholic depression model with C57BL/6J mice and demonstrate that treatment with propolis protects against alcohol-induced depressive symptoms by behavioral tests. In addition, propolis attenuates the injury of nerve cells in the hippocampal region and restores the serum levels of brain-derived neurotrophic factor (BDNF) and dopamine (DA) in mice with alcohol-induced depression. Pathology and biotin tracer assays show that propolis repairs the intestinal leakage caused by alcohol. Additionally, propolis treatment increases the expression levels of intestinal intercellular tight junctions' (TJs') structural proteins Claudin-1, Occludin and zona occludens-1 (ZO-1), as well as the activation state of the liver kinase B1/AMP-activated protein kinase (LKB1/AMPK) signaling pathway, which is closely related to the intestinal permeability. Furthermore, propolis can reduce the levels of pro-inflammatory, lipopolysaccharide (LPS) and fatty-acid-binding protein 2 (FABP2), suggesting the significance of the inflammatory response in alcoholic depression. Collectively, our findings indicate that propolis exerted an improving effect on alcohol-induced depressive symptoms by ameliorating brain gut dysfunction.

Antarctic krill oil ameliorates liver injury in rats exposed to alcohol by regulating bile acids metabolism and gut microbiota.

Bile acids (BAs) metabolism plays an important role in alcohol liver disease through the gut microflora-bile acids-liver axis. Antarctic Krill Oil (AKO) has protective effects on the liver, while whether AKO can protect against liver injury caused by alcohol is unclear. This study investigated the effects of AKO on BAs metabolism and intestinal microbiota in a rat model of alcohol-induced liver disease. Sprague-Dawley rats were randomly divided into five groups: control group, model group, low-dose AKO-treatment group (100 mg/kg/d), high-dose AKO-treatment group (200 mg/kg/d), and AKO control group (200 mg/kg/d). Administration of alcohol (8 to 10 mL/kg/d) for 16 weeks induced liver injury in rats. We found that AKO supplementation significantly protected the liver against alcohol-induced injury, evidenced by allayed hepatic histopathological changes, and inhibited the alcohol-induced elevation of serum biochemical indices. Furthermore, AKO could regulate BAs metabolism by activating the intestinal-hepatic FXR-FGF15-FGFR4 signaling axis with subsequently decreased cholesterol 7α-hydroxylase (CYP7A1) and sterol 12α-hydroxylase (CYP8B1) levels, reduced hepatic BAs production, decreased serum BAs level and increased fecal excretion of BAs. Additionally, 16S rDNA sequencing revealed that the gut microbiome richness and composition were altered in alcohol-treated rats in comparison to the control and AKO-administrated rats. Spearman's correlation analysis showed that differential gut bacterial genera correlated with the levels of BAs profiles in the serum, liver, and feces. These findings suggested that AKO dietary supplementation may protect against alcohol-induced liver injury through modulating BAs metabolism and altering the gut microbiome.

Identifying familial hypercholesterolemia in an early onset ischemic cerebrovascular disease patient and the cascade screening in the pedigree: a case report.

Familial hypercholesterolemia (FH) is one of the most common inherited metabolic disorders characterized by elevated low-density lipid cholesterol (LDL-C) levels that lead to coronary artery disease at an early age and a low occurrence of cerebrovascular disease. Low-density lipoprotein receptor (LDLR) gene mutation is the most common cause of FH. Here, we report a case of a 47-year-old woman who had multiple carotid artery stenosis and brain ischemic foci, an elevated level of LDL-C, underwent eyelid xanthoma excision, and a family history of hyperlipidemia. Thereafter, she was diagnosed with FH according to the Dutch Lipid Clinical Network criteria and whole genome sequencing revealed compound heterozygous LDLR mutations. However, she denied a history of coronary heart disease (CAD). The patient underwent stenting of the right subclavicular artery and right internal carotid artery in our hospital. Lipid-lowering drugs were also administered to prevent stroke recurrence. During a 3-year follow-up, the blood lipid level of the patient reduced, and the condition of intracranial and extracranial vascular stenosis improved. Furthermore, a cascade screening was performed in her pedigree, and 7/9 family members were found to have elevated LDL-C, 6/7 were found to carry one of the two LDLR variants detected in the proband, and in 4/6, the carotid intima-media thickness was ≥1 mm, which was predicted as a high risk factor of cerebrovascular disease. Her relatives with high risks of cardiovascular or cerebrovascular diseases have been under lipid monitoring and management of risk factors since then. To date, no cardiovascular or cerebrovascular event has been reported. In conclusion, this case reminds us to consider FH screening in early-onset stroke or transient ischemic attack patients with elevated LDL-C level. Our report also demonstrates the beneficial role of genetic testing and cascade screening in the relatives of FH patients.

Comprehensive Profiling of Inflammatory Factors Revealed That Growth Differentiation Factor-15 Is an Indicator of Disease Severity in COVID-19 Patients.

To systematically explore potential biomarkers which can predict disease severity in COVID-19 patients and prevent the occurrence or development of severe COVID-19, the levels of 440 factors were analyzed in patients categorized according to COVID-19 disease severity; including asymptomatic, mild, moderate, severe, convalescent and healthy control groups. Factor candidates were validated by ELISA and functional relevance was uncovered by bioinformatics analysis. To identify potential biomarkers of occurrence or development of COVID-19, patient sera from three different severity groups (moderate, severe, and critical) at three time points (admission, remission, and discharge) and the expression levels of candidate biomarkers were measured. Eleven differential factors associated with disease severity were pinpointed from 440 factors across 111 patients of differing disease severity. The dynamic changes of GDF15 reflect the progression of the disease, while the other differential factors include TRAIL R1, IGFBP-1, IGFBP-4, VCAM-1, sFRP-3, FABP2, Transferrin, GDF15, IL-1F7, IL-5Rα, and CD200. Elevation of white blood cell count, neutrophil count, neutrophil-lymphocyte ratio (NLR), Alanine aminotransferase and Aspartate aminotransferase, low lymphocyte and eosinophil counts in the severe group were associated with the severity of COVID-19. GDF15 levels were observed to be associated with the severity of COVID-19 and the dynamic change of GDF15 levels was closely associated with the COVID-19 disease progression. Therefore, GDF15 might serve as an indicator of disease severity in COVID-19 patients.

Transcriptome Analysis of Peripheral Blood Mononuclear Cells Reveals Distinct Immune Response in Asymptomatic and Re-Detectable Positive COVID-19 Patients.

The existence of asymptomatic and re-detectable positive coronavirus disease 2019 (COVID-19) patients presents the disease control challenges of COVID-19. Most studies on immune responses in COVID-19 have focused on moderately or severely symptomatic patients; however, little is known about the immune response in asymptomatic and re-detectable positive (RP) patients. Here we performed a comprehensive analysis of the transcriptomic profiles of peripheral blood mononuclear cells (PBMCs) from 48 COVID-19 patients which included 8 asymptomatic, 13 symptomatic, 15 recovered and 12 RP patients. The weighted gene co-expression network analysis (WGCNA) identified six co-expression modules, of which the turquoise module was positively correlated with the asymptomatic, symptomatic, and recovered COVID-19 patients. The red module positively correlated with symptomatic patients only and the blue and brown modules positively correlated with the RP patients. The analysis by single sample gene set enrichment analysis (ssGSEA) revealed a lower level of IFN response and complement activation in the asymptomatic patients compared with the symptomatic, indicating a weaker immune response of the PBMCs in the asymptomatic patients. In addition, gene set enrichment analysis (GSEA) analysis showed the enrichment of TNFα/NF-κB and influenza infection in the RP patients compared with the recovered patients, indicating a hyper-inflammatory immune response in the PBMC of RP patients. Thus our findings could extend our understanding of host immune response during the progression of COVID-19 disease and assist clinical management and the immunotherapy development for COVID-19.

Differential Antibody Response to Inactivated COVID-19 Vaccines in Healthy Subjects.

The appearance and magnitude of the immune response and the related factors correlated with SARS-CoV-2 vaccination need to be defined. Here, we enrolled a prospective cohort of 52 participants who received two doses of inactivated vaccines (BBIBP-CorV). Their serial plasma samples (n = 260) over 2 months were collected at five timepoints. We measured antibody responses (NAb, S-IgG and S-IgM) and routine blood parameter. NAb seroconversion occurred in 90.7% of vaccinated individuals and four typical NAb kinetic curves were observed. All of the participants who seroconverted after the first dose were females and had relatively high prevaccine estradiol levels. Moreover, those without seroconversion tended to have lower lymphocyte counts and higher serum SAA levels than those who experienced seroconversion. The NAb titers in young vaccine recipients had a significantly higher peak than those in elderly recipients. S-IgG and S-IgM dynamics were accompanied by similar trends in NAb. Here, we gained insight into the dynamic changes in NAbs and preliminarily explored the prevaccine blood parameters related to the kinetic subclasses, providing a reference for vaccination strategies.

[Growing of human embryonic stem cells on feeders derived from themselves].

This study was carried out to determine whether mesenchymal stem cells (MSCs) derived from teratoma of human embryonic stem cells (hESCs) function as feeder cells to support hESCs growth. Approximately 5x10(6) hESCs were injected into the hind limb muscle of each SCID-beige mouse to form teratoma. After 8 weeks, the MSCs were isolated from the teratoma and cultured in Mesencult medium. Purified MSCs were then used as the feeder cells for hESCs culture. High purity MSCs derived from teratoma were isolated. The cells were morphologically similar to bone marrow MSCs (bMSCs). The teratoma-derived MSCs were negative for CD34 and CD45 but positive for CD29, CD49b, CD105, CD73, and CD90, which resembled those expressed by bMSCs. After passaged on MSCs feeder cells more than 10 passages, hESCs maintained hESC characteristics in morphology. Reverse PCR showed the expression of Oct4 and Nanog. SSEA-1 was negative and SSEA-4, TRA-1-60, and TRA-1-81 were positive. Alkaline phosphatase staining showed positive results.The karyotype remained normal. Moreover, the hECSs cultured on teratoma-derived MSCs formed teratoma in vivo and embryoid body in vitro confirmed their pluripotency. Accordingly, MSCs derived from hESCs by in vivo differentiation can be used as the feeder cells for hESCs culture.