Immunogenomic Landscape of B cells in Patients with Septic Shock

doi:10.21203/rs.3.rs-4896171/v1

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Immunogenomic Landscape of B cells in Patients with Septic Shock

https://doi.org/10.21203/rs.3.rs-4896171/v1

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Background.

B cells play a critical role in protecting against infections. Decreased cell number, altered phenotype and function were found in B cells from patients with sepsis/septic shock, however, the underlying molecular mechanisms were not elucidated. In the present study, we aimed to explore the B cells composition, gene expressions and B cell receptor (BCR) characterization in patients with septic shock.

Methods.

B cells were isolated from peripheral blood of patients with septic shock and healthy controls (HCs). Bulk RNA sequencing, single-cell RNA and BCR sequencing were performed. Subsequent cellular and molecular experiments were conducted to verify the analysis.

Results.

Conclusion.

Our study provides a comprehensive genomic picture of B cells from patients with septic shock. We explored the underlying molecular mechanism involved in abnormal B cell compartment and function, which would be promising targets for lymphopenia and immunosuppression in sepsis/septic shock patients.

B cell

Septic shock

Single-cell RNA sequencing (scRNA-seq)

Single-cell B cell receptor sequencing (scBCR-seq)

Lymphopenia occurs in nearly two-third of septic patients and is associated with high mortality and adverse outcomes^[1]. Sepsis-driven apoptosis plays a critical role in lymphopenia, thus favoring immunosuppression^[2]. Therapy targeting lymphocytes apoptosis represents a promising approach to restore immune competence in sepsis.

B lymphocytes is an essential component of humoral immune response and protect against infections through antibody production, cytokine secretion and antigen presentation^[3]. Previous studies have shown that the circulating B cell counts in septic patients were decreased, which was associated with poor prognosis^[4–7]. Besides, altered phenotype and abnormal serum immunoglobulin levels were also found in patients with sepsis^{[8, 9]}. The clarification of the underlying molecular mechanism of B-cell immunity would help to develop new strategies to reverse immunosuppression status in sepsis.

The B cell receptor (BCR), composed of two heavy chains and two light chains, recognizes and interacts with foreign antigens to mediate B cell activation as well as antibody production^[10]. The recombination of variable (V), diversity (D) joining (J) in the heavy chain, V and J gene segments in the light chain in B cells can help generate the diverse repertoires of the BCRs, which is capable of recognizing a wide range of pathogen epitopes^[11]. A comprehensive landscape of BCR would contribute to a deeper understanding of the humoral responses.

Here, we purified B cells from patients with septic shock and healthy controls (HCs) matched by age and sex, subjected single-cell RNA sequencing (scRNA-seq) paired with single-cell B cell receptor sequencing (scBCR-seq) to systematically characterize the cellular composition, gene expressions and BCR clonality. Further, we performed functional analysis to explore the potential molecular mechanism of the decreased B cell counts in patients with septic shock.

Patients and Ethics

This prospective study was conducted at Peking Union Medical College Hospital during October 2023 to July 2024. A total of 41 healthy donors with age-and sex-matched were enrolled as HCs group. Those with any of the following circumstances were excluded: 1) chronic cardiac, liver, renal, lung, immunodeficiency disease; 2) infection in the last three months; 3) history of tumor disease; 4) Pregnant or lactating women.

Patients aged between 18 and 70 years old who met the diagnosis of septic shock according to sepsis 3.0 criteria were included in this study^[29]. Exclusion criteria included any of the following: 1) patients diagnosed with septic shock more than 48 hours on admission; 2) the maximum dose of norepinephrine less than 0.1ug/kg/min; 3) patients with other types of shock (such as cardiogenic shock, hypovolemic shock or anaphylactic shock) at the same time; 4) patients suffering from hematological malignancies, solid organ tumors, hematopoietic stem cell transplantation, solid organ transplantation, immunodeficiency diseases, autoimmune diseases, chronic allergic diseases, or systemic chronic inflammation; 5) use of any kind of immunomodulators or immunosuppressive drugs, cytotoxic drugs or corticosteroids within the past 3 months; 6) patients with acute infection or acute allergy within the past 3 months; 7) female patients who are pregnant or breastfeeding.

Approval was obtained from Ethics Committee of Peking Union Medical College Hospital (JS-3480D). Informed consent was obtained from the participants or their authorized individuals. ln this study, all processes comply with the 1964 Declaration of Helsinki and its later amendments.

B cell Isolation

PBMCs were isolated by Ficoll-Hypaque density-gradient centrifugation and labeled with CD19 Microbeads (Miltenyi Biotec). B cells were isolated by positive selection using LS column and magnetic bead separator. The viability of isolated B cells > 90%.

Bulk RNA-sequencing and data analysis

Total RNA was extracted from CD19⁺ B cells of three patients with septic shock and four age-, sex- matched HCs. RNA sequencing was performed by Biomarker Technologies on an Illumina NovaSeq platform (Beijing, China). The raw reeds were processed with BMKCloud (www.biocloud.net) online platform using a bioinformatic pipelinetool. Packages limma (V3.58.1) was used to analyzed DEGs in the R environment. DEGs were determined by absolute (log2Foldchange) > 1.5 and adjusted p value < 0.05. The package clusterProfiler (V4.10.0) was used to conduct the KEGG pathway analysis^[30]. Data was visualized with the packages ggplot2 (V3.4.4) in the R environment.

Flow cytometry

For surface staining, 2×10⁶/100 µl cells were stained with surface antibody for 20 minutes at room temperature. The antibody was used as follows: FITC-conjugated anti-human CD38, APC-conjugated anti-human CD27, PE-Cy7-conjugated anti-human CD19 (Biolegend, USA). After surface staining, cells were washed twice with PBS and the Foxp3 Transcription Factor Staining Buffer Set (Invitrogen) was used for PE-conjugated anti-human Ki67 (Biolegend, USA) for intracellular staining. Cell apoptosis rate was measured using a FITC/PE Annexin V Apoptosis Detection Kit (BD, Biosciences) following the manufacturer’s instructions. Samples were analyzed on BD LSRFortessa (BD Biosciences) and data was analyzed using FlowJo software (TreeStar, USA).

Single-cell data sequencing and data analysis

Purified CD19⁺ B cells from five patients with septic shock and five age-, sex-matched HCs were collected for scRNA-seq using the V3.1 single-cell reagent kit (10 × Genomics) and sequenced by Biomarker Technologies on an Illumina NovaSeq platform (Beijing, China). Raw data were processed following the standard Chromium Cell Ranger pipeline (V4.0.0) against the GRCh38 human reference genome. Samples were merged and data analysis were conducted using the Seurat package (V5.0.1) in the R (V4.3.2) environment as described previously^{[31, 32]}. We utilized the scRepertoire (V1.12.0) for BCR analysis in the dataset. Paired scBCR-seq data were integrated with scRNA-seq based on their matched unique cell barcodes.

Western blotting

Cells were lysed with RIPA lysis buffer mixed with protease inhibitor cocktail (Beyotime, China). The total protein concentration was quantified using a BCA protein assay kit (ThermoFisher, USA). After separation by SDS-PAGE, the proteins were transferred onto a PVDF membrane (Millipore, USA). The membrane was then blocked with 5% bovine serum albumin (BSA) for 1 hour at room temperature and incubated with primary antibodies overnight at 4°C. Subsequently, the membrane was washed three times and incubated with horseradish peroxidase (HRP)-conjugated secondary antibody (1:5000) for 1 hour at room temperature. The results were visualized by enhanced chemiluminescence (Peirce) and signals were read and analyzed using Image Lab software (Bio-Rad). Primary antibody was used as follows: ADM (Proteintech, Cat#10778-1-AP); DEPDC1 (Abcepta, Cat#AP5428a); KIF18B (Immunoway, Cat#YN5266); SOCS3 (Abcam, Cat#ab280884); CA8 (Proteintech, Cat#12391-1-AP); RRM2 (Proteintech, Cat#11661-1-AP); MMP2 (Abcam, Cat#ab92536); Akt (Abcam, Cat#ab32505); p-Akt (Abcam, Cat#ab192623).

RNA interference

Small interfering RNA was purchased from RIBOBIO (Guangzhou, China): RRM2 targeting siRNA (5’-CGUCGAUAUUCUGGCUCAATT-3’; 5’-UUGAGCCAGAAUAUCGACGTT-3’), CA8 targeting siRNA (5’- GCACACGGUUAAUUUCAAATT-3’; 5’-UUUGAAAUUAACCGUGUGCTT-3’). SF Cell Line 4D-Nucleofector X Kit L was used (Lonza, V4XC-2024) and transfection was conducted on Lonza 4D Nucleofection System (Lonza, Germany) following the manufacturer’s guidelines.

Cell counting kit-8

ARH77 cell lines were seeded in a 96-well plate (Corning Life Sciences, USA) and 10 µl CCK8 reagent (Dojindo, China) was added for 2 h of incubation. The absorbance at 450 nm was measured using a microplate reader (Biorad, USA).

Transmission Electron Microscopy

CD19⁺ B cells were freshly isolated and fixed with 2.5% glutaraldehyde in 0.1 M Sorenson’s buffer for 3 hours, the images were examined under the TME-1400 plus electron microscope at 5,000–50,000-fold magnification.

Statistical analysis

The graphs and statistical analysis in this study was conducted in Graphpad Prism (V9.0). Data were present as mean ± standard deviation. Normal distribution was tested. Student’s t test was used for normal distributed data, otherwise the Mann-Whitney test was used. P < 0.05 was considered statistically significant.

Plasmablast population is expanded in patients with septic shock

To systematically examine the gene signatures of B cells in patients with septic shock, we first isolated peripheral blood mononuclear cells (PBMCs), sorted total CD19⁺ B cells and performed bulk RNA-seq analysis of five patients with septic shock and HCs matched. Clinical information of the included patients was demonstrated in Table 1. 229 genes were up-regulated and 6 genes were down-regulated in patients with septic shock compared with HCs as visualized with volcano plot and heatmap (Fig. 1A-B). Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that the up-regulated genes were mainly associated with cell cycle (Fig. 1C). Subsequent flow cytometry analysis revealed significantly increased Ki67 expression in B cells from patients with septic shock (Fig. 1D). These findings suggested that the proliferation ability of B cells is enhanced in patients with septic shock.

Table 1

Clinical data of patients with septic shock
	Age/ Gender	Comorbidities	Infection site	Bacteria	ICU admission								Outcome
	Age/ Gender	Comorbidities	Infection site	Bacteria	APACHE Ⅱ score	SOFA score	Organ Support	NE (µg/ kg/min)	Lactate (mmol/L)	WBC (10⁹/L)	Lymphocyte (10⁹/L)	B cell (10⁹/L)	Outcome
Patient1	67/M	Hypertension Diabetes	Abdomen Bacteraemia	Klebsiella pneumoniae	15	11	MV	1.80	2.9	11.10	0.19	0.057	Survived
Patient 2	40/M	-	Central nervous system Bacteraemia	Klebsiella pneumoniae	22	16	MV	0.57	5.1	3.82	0.43	0.077	Survived
Patient 3	43/F	-	Skin Bacteraemia	Staphylococcus aureus	27	15	MV, CRRT	1.93	6.1	17.06	0.69	0.208	Survived
Patient 4	35/F	Diabetes	Urine Bacteraemia	Escherichia coli	34	18	MV, CRRT	0.87	3.1	6.76	0.4	0.123	Died
Patient 5	53/M	-	Abdomen	Enterobacterium aerogenes	15	8	MV, CRRT	1.11	5.4	26.86	0.56	0.144	Survived
APACHE Acute Physiology and Chronic Health evaluation, CRRT Continuous Renal Replacement Therapy, MV Mechanical ventilation, NE Norepinephrine, SOFA Sequential Organ Failure Assessment, WBC White Blood Cell.

To gain deeper insight into B-cell response of septic shock patients, we then adopted single-cell RNA-sequencing (scRNA-seq) of purified B cells and constructed 5’ gene expression libraries as well as B cell receptor (BCR) libraries. Unsupervised clustering by Seurat identified five major populations based on canonical marker gene expressions (Fig. 1E). Increased frequency of plasmablast and plasma B cells was observed in patients with septic shock compared with HCs (Fig. 1F-G). We enrolled another 24 patients with septic shock and confirmed that the frequency of CD27⁺CD38⁺ plasmablast/plasma B cells was higher in individuals with septic shock compared with HCs by flow cytometry (Fig. 1H-I). Moreover, the dividing B cell populations were mainly plasmablast/plasma B cells as the Ki67 expression was significantly higher on CD27⁺CD38⁺ than other (CD27⁻CD38⁻, CD27⁺CD38⁻, CD27⁻CD38⁺) populations of CD19⁺ B cells in patients with septic shock (Fig. 1H-I). These results showed that plasmablast population is expanded in patients.

Characterization of BCRs in patients with septic shock

We next explored the immunoglobin repertoires by analyzing the paired scBCR-seq data generated from the same cDNA libraries. We detected decreased numbers of Ig heavy-chain (IGH) clonotype in patients with septic shock compared with HCs (Fig. 2A). We observed that both the number and length of CDR3 of BCR were significantly decreased in patients compared with controls (Fig. 2B). The diversity of BCR clonotype was lower in individuals with septic shock compared with HCs scored with Shannon and Inv. Simpson (Fig. 2C). We further integrated the scRNA-seq and scBCR-seq data and found that cells of most expanded clones in patients with septic shock were plasmablasts (Fig. 2D). The BCR clonotypes in all B-cell subtypes from patients with septic shock were more expanded and the composition of large and medium clonotypes were relatively higher in septic shock patients compared with normal controls (Fig. 2E). Analysis of the differential genes in B subsets revealed that the IGHV6-1 gene was up-regulated in both plasmablast and plasma B subset of patients with septic shock compared with HCs (Fig. 2F). Our observations suggest that lower BCR clonotype diversity and clonality might be associated with immunosuppression in patients with septic shock.

Carbonic anhydrase-related protein VIII (CA8) promotes plasmablast expansion in patients with septic shock

To further understand the underlying molecular mechanisms that contributes to the expanded plasmablast population in patients with septic shock, we analyzed the differential expressed genes (DEGs) of plasmablast between patients with septic shock and HCs in scRNA-seq data. ADM, DEPDC1, SOCS3, CA8 and KIF18B ranked the top 5 DEGs that were significantly up-regulated in plasmablast of patients with septic shock compared with HCs (Fig. 3A). The findings were also confirmed by bulk RNA-seq data analysis (Fig. 3B). Meanwhile, we performed immunoblotting assay and quantified their expressions from freshly isolated B cells, which showed increased CA8 and adrenomedullin (ADM) protein levels in patients with septic shock (Fig. 3C-D).

CA8 was previously reported to promote renal cell carcinoma (RCC) proliferation through pAKT signaling pathway and up-regulating MMP2 expression^[12]. To investigate whether CA8 promote plasmablast proliferation, we knockdown CA8 expression on ARH77 cell line and examined the impact on cell viability and proliferation (Fig. 3E). Knockdown of CA8 significantly decreased cell viability through inhibiting cell proliferation in ARH77 cell line (Fig. 3F-G). The apoptotic rate of ARH77 was not affected by CA8 knockdown (Fig. 3G). Moreover, knockdown of CA8 showed decreased pAKT but not MMP2 protein level in ARH77 cell line (Fig. 3H), which indicated that CA8 promote proliferation of plasmablast through pAKT signaling pathway.

ADM drive B-cell apoptosis through RRM2-related cell cycle arrest in patients with septic shock

Since we observed higher expression of ADM in B cells from patients with septic shock, we next explored the role of ADM in the B-cell responses. Consistent with previous reports, we found a significantly higher percentage of 7AAD⁺Annexin V⁺ late apoptotic cells, which could explain the decreased B cell numbers in individuals with septic shock (Fig. 4A-B). Interestingly, approximately 30% of B cells from patients with septic shock displayed damaged or abnormal mitochondria structure by electron microscope (Fig. 4C). Either in vitro stimulation by epinephrine (Epi) or norepinephrine (NE) could increase the frequency of 7AAD⁺Annexin V⁺ late apoptotic cells in a dose-dependent manner, with greater effect on septic shock-derived B cells (Fig. 4A, C-D).

The expression of ribonucleotide reductase regulatory subunit M2 (RRM2) was previously reported to increase DNA damage and mitochondria dysfunction^[13], and was significantly higher in patients with septic shock from bulk RNA-seq data (Fig. 5A). RRM2 was mainly expressed on plasmablast and was relatively higher in naïve, memory-unswitched and plamablast B cells from patients with septic shock from scRNA-seq data (Fig. 5B). Immunoblotting assay confirmed higher expression of RRM2 in B cell from patients with septic shock compared with HCs (Fig. 5C-D). Knockdown RRM2 expression in septic shock-derived B cells could significantly decrease 7AAD⁺Annexin V⁺ late apoptotic cells, demonstrating the role of RRM2 in promoting B-cell apoptosis in septic shock individuals (Fig. 5E-F). Finally, we investigated whether ADM promoted B-cell apoptosis through RRM2-related cell death. Both Epi and NE could up-regulate RRM2 expression in septic shock-derived B cells (Fig. 5G), and knockdown RRM2 reverse Epi or NE induced B-cell apoptosis in both patients and HCs (Fig. 5H). Collectively, our findings suggest that septic shock B cells might have metabolic disorders and ADM could drive RRM2-related cell death.

It is well established that septic shock is a leading cause of mortality in intensive care unit accompanied with immune dysfunctions. The present study is the first to systematically give a global picture of B cells, BCR clonality at the single-cell level and explain the molecular mechanism of altered B compartments as well as decreased B cell numbers in septic shock patients.

A previous study has isolated PBMCs from two patients secondary to pneumonia infected by gram-negative bacteria for scRNA-seq and found increased proportions of plasma cells, which might be driven by NK cells through IFN signaling pathways^[14]. Daniele et.al found that sepsis expanded a subset of CD39^hi plasmablasts, which acts as important drivers of sepsis-induced immunosuppression^[15]. In consistent with previous findings, we found expanded plasmablast populations in patients with septic shock by scRNA-seq data and further confirmed by flow cytometry. CA8 regulated intracellular calcium signaling that orchestrating neuronal excitability and analgesia^[16]. However, the expression and role of CA8 in sepsis/septic shock has not been elucidated. Our study showed that CA8 was significantly up-regulated in septic shock-derived B cells and promoted plasmablast proliferation through activating pAkt signaling pathway, which explained the plasmablast expansion by septic shock status.

Septic shock altered B cell phenotype and shaped B cell response^{[8, 17]}. BCR characterization in our study showed decreased number and length of CDR3 as well as lower clonotype diversity in patients with septic shock, which indicated that B cell function was impaired. However, transcriptome analysis by bulk RNA-seq data in our present study revealed that most of the DEGs were up-regulated in septic shock B cells (229 up-regulated but only 6 down-regulated). Moreover, lower immunoglobulin levels and higher free light chain concentration were reported in septic patients^{[18, 19]}. In this study, we found that the number of IGH clonotype was significantly decreased in patients with septic shock, while the number of Ig light-chain (IGL) clonotype was comparable between patients and HCs. These observations might explain the higher free light chain concentration in serum of patients with septic shock.

We found that B cells from patients with septic shock displayed mitochondrial disorders and increased apoptotic rate. A previous finding showed that septic B cells had increased glycolytic flux and were metabolically reprogrammed toward aerobic glycolysis^[15], which supported our observations. Therefore, we proposed that mitochondrial metabolic disorders in patients with septic shock might result in abnormal B cell responses and B cell apoptosis. Further study would be applied to identify the underlying metabolic mechanism affecting B-cell responses in septic shock patients.

ADM is a 52 amino acid peptide involved in the regulation of vascular tone and endothelial barrier function. Biologically active adrenomedullin (bio-ADM) concentration was significantly higher in patients with septic shock and serves as a biomarker associated with organ failure and 30-day mortality^[20–22]. ADM could directly affect immune cells. A recent study found that hypoxia could induce ADM from lung epithelial and ADM could promoted group 2 innate lymphoid cells (ILC2s) activation^[23]. We found that Adm transcription was increased in septic shock-derived B cells. Consistently, the protein level of ADM was significantly higher. Importantly, ADM mediate B cells apoptosis through RRM2-related cell death in vitro. A number of studies have elucidated the reduced number of circulating B lymphocytes in sepsis, which is associated with poor prognosis. Therefore, our results indicated that septic shock induced ADM expression and promoted B cell apoptosis. Moreover, it would be an interesting topic to explore whether ADM mediate lymphopenia in patients with septic shock in our future study.

RRM2 is responsible for the ribonucleotide dezoxyribonucleotide conversion during the S phase of the cell cycle and serves as a proliferation marker in various cancers^[24–26]. Our results found a higher expression of RRM2 in B cells from septic shock patients and responsible for increased B cell apoptosis. Moreover, ADM could increase RRM2 expression in B cells and knockdown RRM2 could partly reverse ADM induced B cell apoptosis. Recent study has found that RRM2 was highly expressed in CLP-induced septic mice and related to ferroptosis^{[27, 28]}. However, we did not observe ferroptosis morphology of B cells from septic shock patients under electron microscope.

We found expansion of plasmablast population in patients with septic shock. However, both the BCR clonotype diversity and clonality were decreased. The CA8 expression was higher in B cells and promoted plasmablast proliferation through Akt signaling pathway. We further discovered that adrenomedullin (ADM) expression was up-regulated in septic shock-derived B cells compared with HCs. Moreover, B cells from septic shock patients display abnormal mitochondria structure and stimulation of ADM in vitro promoted B cell apoptosis through ribonucleotide reductase regulatory subunit M2 (RRM2)-related cell death. Our study provides a comprehensive genomic picture of B cells from patients with septic shock. We explored the underlying molecular mechanism involved in abnormal B cell compartment and function, which would be promising targets for lymphopenia and immunosuppression in sepsis/septic shock patients.

ADM, adrenomedullin; BCR, B cell receptor; bio-ADM, Biologically active adrenomedullin; DEGs, differential expressed genes; Epi, epinephrine; HCs, healthy controls; HRP, horseradish peroxidase; IGH, Ig heavy-chain; IGL, light-chain; ILC2s, 2 innate lymphoid cells; KEGG, Kyoto Encyclopedia of Genes and Genomes; PBMCs, peripheral blood mononuclear cells; RCC, renal cell carcinoma; RRM, ribonucleotide reductase regulatory subunit M; scBCR-seq, B cell receptor sequencing; scRNA-seq, single-cell RNA sequencing.

Ethics approval and consent to participate

Consent for publication: Not applicable.

Funding

We acknowledge the support from: National Key Research and Development Program of China from Ministry of Science and Technology of the People's Republic of China (2021YFC2500801, 2022YFC2304601); CAMS Innovation Fund for Medical Sciences (CIFMS) 2021-I2M-1-062 from Chinese Academy of Medical Sciences; National High Level Hospital Clinical Research Funding(2022-PUMCH-D-005, 2022-PUMCH-B-126, 2022-PUMCH-B-111); National key clinical specialty construction projects from National Health Commission.

Competing interests.

All authors declare that they have no conflicts of interest to this work.

Data availability

The raw sequence data reported in this paper have been deposited in the Genome Sequence Archive (Genomics, Proteomics & Bioinformatics 2021) in National Genomics Data Center (Nucleic Acids Res 2022), China National Center for Bioinformation/Beijing Institute of Genomics, Chinese Academy of Sci- ences (GSA-Human: subHRA011827) that are publicly accessible at https://ngdc.cncb.ac.cn/gsa-human.

Acknowledgements

We thank Biomedical Engineering Facility of National Infrastructures for Translational Medicine, Institute of Clinical Medicine, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences and Peking Union Medical College for technical support.

Author contributions.

B.D, L.W., X.Y.W. and Y.Y.L. designed the study. Y.Y.L., Y.C., S.L., J.M.P, X.Y. H., W.J., C.Y. W. and R. D. were in charge of clinical work and interpreted the clinical data. X.Y.W., Y.Y.L. and Q.Z. performed the laboratory work and statistical analyses. B.D. and L.W. directed the writing and revised the first version of manuscript. The first draft of the manuscript was written by X.Y.W. and Y.Y.L., and all authors commented on previous versions of the manuscript. All authors read and approved the final manuscript.

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No competing interests reported.

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Immunogenomic Landscape of B cells in Patients with Septic Shock

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Abstract

Background.

Methods.

Results.

Conclusion.

Figures

Introduction

Methods

Patients and Ethics

B cell Isolation

Bulk RNA-sequencing and data analysis

Flow cytometry

Single-cell data sequencing and data analysis

Western blotting

RNA interference

Cell counting kit-8

Transmission Electron Microscopy

Statistical analysis

Results

Plasmablast population is expanded in patients with septic shock

Characterization of BCRs in patients with septic shock

Carbonic anhydrase-related protein VIII (CA8) promotes plasmablast expansion in patients with septic shock

ADM drive B-cell apoptosis through RRM2-related cell cycle arrest in patients with septic shock

Discussion

Conclusion

Abbreviations

Declarations

References

Additional Declarations

Supplementary Files

Status:

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