Antibody-producing Cells Research Articles

Selective Recruitment of a Synthetic Histone Acetyltransferase Can Boost CHO Cell Productivity.

Industrial production of biologics typically involves the integration of transgenes into host cell genomes, most often Chinese hamster ovary (CHO) cells. Epigenetic control of transgene expression is a major determinant of production titers. Although the cytomegalovirus (CMV) promoter has long been used to drive industrial transgene expression, we found that its associated histones are suboptimally acetylated in CHO cells, providing an opportunity to enhance productivity through epigenetic manipulation. Expression of monoclonal antibody mRNAs increased up to 12-fold when a CRISPR-dCas9 system delivered the catalytic domain of a histone acetyltransferase to the CMV promoter. This effect was far stronger than when promoter DNA was selectively demethylated using dCas9 fused to a 5-methylcytosine dioxygenase. Mechanistically, acetylation-mediated transcriptional activation involved heightened phosphorylation and activity of RNA polymerase II, enabling it to escape promoter-proximal pausing at the transgene. This approach almost doubled the titer and specific productivity of antibody-producing CHO cells, demonstrating the potential for biomanufacturing.

IRF5 Controls Plasma Cell Generation and Antibody Production via Distinct Mechanisms Depending on the Antigenic Trigger.

Elevated levels of serum autoantibodies are a hallmark of systemic lupus erythematosus (SLE) and are produced by plasma cells in response to a variety of antigenic triggers. In SLE, the triggers are complex and may include both T cell-dependent/-independent and TLR-dependent/-independent mechanisms of immune activation, which ultimately contributes to the significant immune dysregulation seen in patients at the level of cytokine production and cellular activation (B cells, T cells, dendritic cells, neutrophils and macrophages). Interferon regulatory factor 5 (IRF5) has been identified as an autoimmune susceptibility gene and polymorphisms in IRF5 associate with altered expression and hyper-activation in distinct SLE immune cell subsets. To gain further insight into the mechanisms that drive IRF5-mediated SLE immune activation, we characterised wild-type (WT) and Irf5-/- Balb/c mice in response to immunisation. WT and Irf5-/- Balb/c mice were immunised to activate various signalling pathways invivo followed by systemic immunophenotyping and detection of antibody production by multi-colour flow cytometry and ELISPOT. We identified two pathways, TLR9-dependent and T cell-dependent that resulted in IRF5 cell type-specific function. Immunisation with either CpG-B + Alum or NP-KLH + Alum but not with R848 + Alum, NP-LPS + Alum or NP-Ficoll+Alum resulted in decreased plasma cell generation and reduced antibody production in Irf5-/- mice. Notably, the mechanism(s) leading to this downstream phenotype was distinct. In CpG-B + Alum immunised mice, we found reduced activation of plasmacytoid dendritic cells, resulting in reduced IFNα and IL6 production in Irf5-/- mice. Conversely, mice immunised with NP-KLH + Alum had reduced numbers of T follicular helper cells and germinal centre B cells with reduced expression of Bcl6 in Irf5-/- mice. Moreover, T follicular helper cells from Irf5-/- mice were functionally defective. Even though the downstream phenotype of reduced antibody production in Irf5-/- mice was conserved between T cell-dependent and TLR9-dependent immunisation, the mechanisms leading to this phenotype were antigen- and cell type-specific.

A multimodal digital microfluidic testing platform for antibody-producing cell lines.

In recent years, monoclonal antibodies (mAbs) have become a powerful tool in the treatment of human diseases. Currently, over 100 mAbs have received approval for therapeutic use in the US, with wide-ranging applications from cancer to infectious diseases. The predominant method of producing antibodies for therapeutics involves expression in mammalian cell lines. In the mAb production process, significant optimization is typically done to maximize antibody titres from cells grown in bioreactors. Therefore, systems that can miniaturize and automate cell line testing (e.g., viability and antibody production assays) are valuable in reducing therapeutic mAb development costs. Here we present a novel platform for cell line optimization for mAb production using digital microfluidics. The platform enables testing of cell culture samples in 6-8 μL droplets with semi-automated viability, media pH, and antibody production assays. This system provides a unique bridge between cell growth and productivity metrics, while minimizing culture volume requirements for daily testing. We propose that this technology and its future iterations has the potential to help reduce the time-to-market and development costs of antibody-producing cell lines.

Immune Checkpoints in B Cells: Unlocking New Potentials in Cancer Treatment.

B cells are crucial component of humoral immunity, and their role in the tumor immune microenvironment (TME) has garnered significant attention in recent years. These cells hold great potential and application prospects in the field of tumor immunotherapy. Research has demonstrated that the TME can remodel various B cell functions, including proliferation, differentiation, antigen presentation, and antibody production, thereby invalidating the anti-tumor effects of B cells. Concurrently, numerous immune checkpoints (ICs) on the surface of B cells are upregulated. Aberrant B-cell IC signals not only impair the function of B cells themselves, but also modulate the tumor-killing effects of other immune cells, ultimately fostering an immunosuppressive TME and facilitating tumor immune escape. Blocking ICs on B cells is beneficial for reversing the immunosuppressive TME and restoring anti-tumor immune responses. In this paper, the intricate connection between B-cell ICs and the TME is delved into, emphasizing the critical role of targeting B-cell ICs in anti-tumor immunity, which may provide valuable insights for the future development of tumor immunotherapy based on B cells.

Unveiling the enigmatic roles of basophils in HIV infection: A narrative review.

The intricate interplay between the human immunodeficiency virus (HIV) and the immune system has long been a focal point in understanding disease progression. Among the myriad of immune cells, basophils, often overshadowed, have recently emerged as pivotal contributors to the complex immunological landscape of HIV infection. This paper aims to provide a succinct overview of the enigmatic roles of basophils in HIV pathogenesis, elucidating their multifaceted functions and implications. Basophils, conventionally perceived as minor players in immune responses, exhibit active participation in HIV infection. Their activation triggered by viral antigens, cytokines, and immune complexes orchestrates a cascade of immune events, influencing immune modulation, cytokine release, and the activation of adaptive immune cells. Furthermore, basophils function as antigen-presenting cells, potentially impacting viral dissemination and immune dysregulation. Additionally, basophils serve as crucial regulators in HIV infection through cytokine secretion, notably interleukin (IL)-4, IL-13, and IL-3, influencing immune cell differentiation, polarization, and antibody production. Their interactions with various immune cells intricately shape the immune response against HIV, impacting disease progression and immune equilibrium. Moreover, harnessing basophils as potential vaccine targets or immune modulators represents a compelling avenue for future research. In conclusion, the emerging understanding of basophils' multifaceted involvement in HIV infection challenges prior perceptions and underscores their significance in shaping immune responses and disease outcomes. This abstraction highlights the need for continued research to unlock the full potential of basophils, paving the way for novel strategies in combatting HIV/AIDS.

TM9SF1 expression correlates with autoimmune disease activity and regulates antibody production through mTOR-dependent autophagy

BackgroundTransmembrane 9 superfamily member 1 (TM9SF1) is involved in inflammation. Since both inflammatory and autoimmune diseases are linked to immune cells regulation, this study investigated the association between TM9SF1 expression and autoimmune disease activity. As B cell differentiation and autoantibody production exacerbate autoimmune disease, the signaling pathways involved in these processes were explored.MethodsTm9sf1−/− mouse rheumatoid arthritis (RA) and systemic lupus erythematosus (SLE) models were used to verify the relationship between gene expression and disease severity. Peripheral blood mononuclear cells (PBMCs) from 156 RA and 145 SLE patients were used to explore the relationship between TM9SF1 expression and disease activity. The effectiveness of TM9SF1 as a predictor of disease activity was assessed using multiple logistic regression and receiver operating characteristic (ROC) curves. The signaling pathways regulated by TM9SF1 in B cell maturation and antibody production were conducted by plasma cell induction experiment in vitro.ResultsThe Tm9sf1−/− RA and SLE model mice produced fewer autoantibodies and showed reduced disease severity relative to wild-type (WT) mice. TM9SF1 levels in PBMCs of patients were higher than those in healthy controls, and were reduced in patients with low disease activity relative to those with active RA and SLE. Furthermore, TM9SF1 levels were positively linked with autoantibody titers and pro-inflammatory cytokine levels in both diseases. ROC analyses indicated TM9SF1 outperformed several important clinical indicators in predicting disease activity (area under the curve (AUC) were 0.858 and 0.876 for RA and SLE, respectively). In vitro experiments demonstrated that Tm9sf1 knockout blocked differentiation of B cells into antibody-producing plasma cells by activating mTOR and inhibiting autophagy, and mTOR inhibitors such as rapamycin could reverse this effect.ConclusionsThe primary finding was the identification of the molecular mechanism underlying autophagy regulation in B cells, in which Tm9sf1 knockout was found to modulate mTOR-dependent autophagy to block B cell differentiation into antibody-secreting plasma cells. It was also found that TM9SF1 expression level in PBMCs was an accurate indicator of disease activity in patients with RA and SLE, suggesting its clinical potential for monitoring disease activity in these patients.

Advances in the study of artemisinin and its derivatives for the treatment of rheumatic skeletal disorders, autoimmune inflammatory diseases, and autoimmune disorders: a comprehensive review.

Artemisinin and its derivatives are widely recognized as first-line treatments for malaria worldwide. Recent studies have demonstrated that artemisinin-based antimalarial drugs, such as artesunate, dihydroartemisinin, and artemether, not only possess excellent antimalarial properties but also exhibit antitumor, antifungal, and immunomodulatory effects. Researchers globally have synthesized artemisinin derivatives like SM735, SM905, and SM934, which offer advantages such as low toxicity, high bioavailability, and potential immunosuppressive properties. These compounds induce immunosuppression by inhibiting the activation of pathogenic T cells, suppressing B cell activation and antibody production, and enhancing the differentiation of regulatory T cells. This review summarized the mechanisms by which artemisinin and its analogs modulate excessive inflammation and immune responses in rheumatic and skeletal diseases, autoimmune inflammatory diseases, and autoimmune disorders, through pathways including TNF, Toll-like receptors, IL-6, RANKL, MAPK, PI3K/AKT/mTOR, JAK/STAT, and NRF2/GPX4. Notably, in the context of the NF-κB pathway, artemisinin not only inhibits NF-κB expression by disrupting upstream cascades and/or directly binding to NF-κB but also downregulates multiple downstream genes controlled by NF-κB, including inflammatory chemokines and their receptors. These downstream targets regulate various immune cell functions, apoptosis, proliferation, signal transduction, and antioxidant responses, ultimately intervening in systemic autoimmune diseases and autoimmune responses in organs such as the kidneys, nervous system, skin, liver, and biliary system by modulating immune dysregulation and inflammatory responses. Ongoing multicenter randomized clinical trials are investigating the effects of these compounds on rheumatic, inflammatory, and autoimmune diseases, with the aim of translating promising preclinical data into clinical applications.

Repeated COVID-19 mRNA-based vaccination contributes to SARS-CoV-2 neutralizing antibody responses in the mucosa.

To prevent infection by respiratory viruses and consequently limit virus circulation, vaccines need to promote mucosal immunity. The extent to which the currently used messenger RNA (mRNA)-based COVID-19 vaccines induce mucosal immunity remains poorly characterized. We evaluated mucosal neutralizing antibody responses in a cohort of 183 individuals. Participants were sampled at several time points after primary adenovirus vector-based or mRNA-based COVID-19 vaccination and after mRNA-based booster vaccinations. Our findings revealed that repeated vaccination with mRNA boosters promoted severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) neutralizing antibodies in nasal secretions. Nasal and serum neutralizing antibody titers of both IgG and IgA isotypes correlated to one another. We investigated the source of these mucosal antibodies in a mouse model wherein mice received repeated mRNA vaccines for SARS-CoV-2. These experiments indicated that neutralizing antibody-producing cells reside in the spleen and bone marrow, whereas no proof of tissue homing to the respiratory mucosa was observed, despite the detection of mucosal antibodies. Serum transfer experiments confirmed that circulating antibodies were able to migrate to the respiratory mucosa. Collectively, these results demonstrate that, especially upon repeated vaccination, the currently used COVID-19 mRNA vaccines can elicit mucosal neutralizing antibodies and that vaccination might also stimulate mucosal immunity induced by previous SARS-CoV-2 infection. Moreover, migration of circulating antibodies to the respiratory mucosa might be a main mechanism. These findings advance our understanding of mRNA vaccine-induced immunity and have implications for the design of vaccine strategies to combat respiratory infections.

Sensory neurons regulate stimulus-dependent humoral immunity in mouse models of bacterial infection and asthma

Sensory neurons sense pathogenic infiltration to drive innate immune responses, but their role in humoral immunity is unclear. Here, using mouse models of Streptococcus pneumoniae infection and Alternaria alternata asthma, we show that sensory neurons are required for B cell recruitment and antibody production. In response to S. pneumoniae, sensory neuron depletion increases bacterial burden and reduces B cell numbers, IgG release, and neutrophil stimulation. Meanwhile, during A. alternata-induced airway inflammation, sensory neuron depletion decreases B cell population sizes, IgE levels, and asthmatic characteristics. Mechanistically, during bacterial infection, sensory neurons preferentially release vasoactive intestinal polypeptide (VIP). In response to asthma, sensory neurons release substance P. Administration of VIP into sensory neuron-depleted mice suppresses bacterial burden, while VIPR1 deficiency increases infection. Similarly, exogenous substance P delivery aggravates asthma in sensory neuron-depleted mice, while substance P deficiency ameliorates asthma. Our data, thus demonstrate that sensory neurons release select neuropeptides which target B cells dependent on the immunogen.

The function of serine/threonine-specific protein kinases in B cells.

The serine/threonine-specific protein kinases (STKs) are important for cell survival, proliferation, differentiation, and apoptosis. In B cells, these kinases play indispensable roles in regulating important cellular functions. Multiple studies on human and other animal cells have shown that multiple STKs are involved in different stages of B cell development and antibody production. However, how STKs affect B cell development and function is still not completely understood. Considering that B cells are clinically important in immunity and diseases, our understanding of STKs' roles in B cells is in great need of investigation with current technologies. Investigating serine/threonine kinases will not only deepen our insight into B cell-related disorders but also facilitate the identification of more effective drug targets for conditions like lymphoma and systemic lupus erythematosus.

B cell immune repertoire sequencing in tobacco cigarette smoking, vaping, and chronic obstructive pulmonary disease in the COPDGene cohort.

Cigarette smoking (CS) impairs B cell function and antibody production, increasing infection risk. The impact of e-cigarette use ('vaping') and combined CS and vaping ('dual-use') on B cell activity is unclear. To examine B cell receptor sequencing (BCR-seq) profiles associated with CS, vaping, dual-use, COPD-related outcomes, and demographic factors. BCR-seq was performed on blood RNA samples from 234 participants in the COPDGene study. We assessed multivariable associations of B cell function measures (immunoglobulin heavy chain (IGH) subclass expression and usage, class-switching, V-segment usage, and clonal expansion) with CS, vaping, dual-use, COPD severity, age, sex, and race. We adjusted for multiple comparisons using the Benjamini-Hochberg method, identifying significant associations at 5% FDR and suggestive associations at 10% FDR. Among 234 non-Hispanic white (NHW) and African American (AA) participants, CS and dual-use were significantly positively associated with increased secretory IgA production, with dual-use showing the strongest associations. Dual-use was positively associated with class switching and B cell clonal expansion, indicating increased B cell activation, with similar trends in those only smoking or only vaping. We observed significant associations between race and IgG antibody usage. AA participants had higher IgG subclass proportions and lower IgM usage compared to NHW participants. CS and vaping additively enhance B cell activation, most notably in dual-users. Self-reported race was strongly associated with IgG isotype usage. These findings highlight associations between B cell activation and antibody transcription, suggesting potential differences in immune and vaccine responses linked to CS, vaping, and race.

Mechanism of modified mRNA structure in COVID-19 vaccines for inducing neutralizing antibodies

The development of SARS-CoV-2 mRNA vaccines is closely linked to advancements in mRNA manufacturing technology. Structural modifications, such as replacing uridine with 1-methylpseudouridine (1mψ), enhance translation efficiency and help the mRNA evade immune detection. Lipid nanoparticles (LNPs) serve as an effective delivery system. Vaccines like BNT162b2 and mRNA-1273 target the receptor-binding domain (RBD) of the spike (S) protein, prompting B cells to produce neutralizing antibodies that block the RBD from binding to the Angiotensin-Converting Enzyme 2 (ACE2) receptor, preventing infection. These vaccines also stimulate adaptive immune responses by activating CD4+ and CD8+ T cells, with mRNA functioning as an endogenous antigen. Antigen-presenting cells (APCs) present the vaccine antigens via major histocompatibility complex (MHC) class I and II pathways, with CD8+ T cells recognizing MHC class I and destroying infected cells, while CD4+ T cells recognize MHC class II and assist in B cell maturation and antibody production. While mRNA vaccines have proven effective in neutralizing SARS-CoV-2, challenges remain, including the decline in neutralizing antibody titers over time and the emergence of new viral variants.

MERS-CoV Infection and Its Impact on the Expression of TSLP Cytokine and IgG Antibodies: An In Vivo and In Vitro Study.

Thymic stromal lymphopoietin (TSLP) is a proinflammatory cytokine produced by epithelial cells that is involved in the activation of allergic disorders. To date, no study has examined TSLP induction during Middle East respiratory syndrome coronavirus (MERS-CoV) infection. Herein, we aimed to study the effects of the recombinant spike protein of MERS-CoV on TSLP production. Additionally, the effects of recombinant human TSLP (rhTSLP) on B cell survival and antibody production were investigated. B cells were separated using the Human B Cell Enrichment Kit, and B cell survival was measured using the WST-1 Assay Kit. Enzyme-linked immunosorbent assay (ELISA) was used to measure TSLP levels in the sera of both MERS-CoV-infected (n=4; median age, 53 years) and healthy individuals (n=5; median age, 35 years). We showed that the group of infected patients had significantly higher levels of TSLP than healthy controls (37.6 pg/mL vs 19.8 pg/mL, *p<0.05). The levels of TSLP in A549 cells were remarkably increased after 48h of stimulation with recombinant full-length spike protein (rSP) (32.2 pg/mL, p=0.01). B cell survival was greatly enhanced by rhTSLP alone or in combination with rSP (0.02 vs 0.046, and 0.045; **p<0.01, respectively). Our data also showed a significant synergistic effect of rhTSLP and rSP on the augmented response of IgG antibodies against the spike protein of MERS-CoV compared with unstimulated cells (0.156 vs 0.22; *p<0.05). TSLP production is induced in vivo after MERS-CoV infection and in vitro after treatment with the rSP of MERS-CoV, which has a significant effect on the survival of B cells. Our data suggest that TSLP can be used as a strong mucosal adjuvant for vaccine development against MERS-CoV infection. However, further investigation is required to study the functional role of TSLP in MERS-CoV infection.

Single-Batch Expression of an Experimental Recombinant Snakebite Antivenom Based on an Oligoclonal Mixture of Human Monoclonal Antibodies.

Oligoclonal antibodies, which are carefully defined mixtures of monoclonal antibodies, are valuable for the treatment of complex diseases, such as infectionss and cancer. In addition to these areas of medicine, they could be utilized for the treatment of snakebite envenoming, where recombinantly produced monoclonal human antibodies could overcome many of the drawbacks accompanying traditional antivenoms. However, producing multiple individual batches of monoclonal antibodies in an industrial setting is associated with significant costs. Therefore, it is attractive to produce oligoclonal antibodies by mixing multiple antibody-producing cell lines in a single batch to have only one upstream and downstream process. In this study, we selected four antibodies that target different toxins found in the venoms of various elapid snake species, such as mambas and cobras, and generated stable antibody-producing cell lines. Upon co-cultivation, we found the cell line ratios to be stable over 7 days. The purified oligoclonal antibody cocktail contained the anticipated antibody concentrations and bound to the target toxins as expected. These results thus provide a proof of concept for the strategy of mixing multiple cell lines in a single batch to manufacture tailored antivenoms recombinantly, which could be utilized for the treatment of snakebite envenoming and in other fields where oligoclonal antibody mixtures could find utility.

Interleukin 38 reduces antigen-presentation capacity and antibody production after vaccination

The mechanisms that underpin low vaccine responses, which can lead to inadequate protection against infection, are still partially unclear. Interleukin (IL)-38 is a member of the IL-1 family, expressed by B cells among others, that regulates inflammatory responses. A recent study shows that IL-38 suppresses plasma cell generation and antibody production upon immune activation.We hypothesis that IL-38 affects antigen-presentation capacity of innate immune cells, effecting antibody production. Here, we investigated the effect of recombinant human IL-38 on human peripheral blood mononuclear cells and myeloid-derived DCs regarding cytokine production, phagocytosis, and expression of MCH II and co-stimulatory proteins in vitro, and further relate circulating plasma IL-38 concentrations to antibody responses in a cohort of 75 females aged 18–48 vaccinated with BCG and Tdap-IPV.To this end, we found that IL-38 decreased the expression of HLA-DR, HLA-DM, and CD83 on PBMCs, and CD40 and CD86 on MDDCs. IL-38 further impaired phagocytosis capacity of monocytes. Lastly, antibody production against diphtheria toxoids up to eight months post-vaccination was negatively associated with IL-38 plasma concentrations.These data suggest that IL-38 could dampen the effectiveness of antigen-presentation and phagocytosis, and could therefore modulate the immunogenicity of some vaccine types.

No replicating evidence for anti-amyloid-β autoantibodies in cerebral amyloid angiopathy-related inflammation.

Elevated levels of anti-amyloid-β (anti-Aβ) autoantibodies in cerebrospinal fluid (CSF) have been proposed as a diagnostic biomarker for cerebral amyloid angiopathy-related inflammation (CAA-RI). We aimed to independently validate the immunoassay for quantifying these antibodies and evaluate its diagnostic value for CAA-RI. We replicated the immunoassay to detect CSF anti-Aβ autoantibodies using CSF from CAA-RI patients and non-CAA controls with unrelated disorders and further characterized its performance. Moreover, we conducted a literature review of CAA-RI case reports to investigate neuropathological and CSF evidence of the nature of the inflammatory reaction in CAA-RI. The assay demonstrated a high background signal in CSF, which increased and corresponded with higher total immunoglobulin G (IgG) concentration in CSF (rsp = 0.51, p = 0.02). Assay levels were not elevated in CAA-RI patients (n = 6) compared to non-CAA controls (n = 20; p = 0.64). Literature review indicated only occasional presence of B-lymphocytes and plasma cells (i.e., antibody-producing cells), alongside the abundant presence of activated microglial cells, T-cells, and other monocyte lineage cells. CSF analysis did not convincingly indicate intrathecal IgG production. We were unable to reproduce the reported elevation of anti-Aβ autoantibody concentration in CSF of CAA-RI patients. Our findings instead support nonspecific detection of IgG levels in CSF by the assay. Reviewed CAA-RI case reports suggested a widespread cerebral inflammatory reaction. In conclusion, our findings do not support anti-Aβ autoantibodies as a diagnostic biomarker for CAA-RI.

Activation of circulating TFH17 cells associated with activated naive and double negative 2 B cell expansion, and disease activity in systemic lupus erythematosus patients

BackgroundSystemic lupus erythematosus (SLE) is the quintessential autoimmune disease, as it is characterized by hyperactivity of CD4+ T cells and subsequently drives lupus pathology. Follicular helper T (TFH) cells play an important role in B cell maturation and antibody production. However, which specific subset of cTFH cells drives B cell function and contributes to the development of anti-dsDNA antibodies and SLE pathogenesis remains unclear.MethodsPeripheral blood mononuclear cells from SLE patients with inactive (n = 11) and active (n = 21) were used to determine and detect frequencies and phenotypes of circulating TFH cells (cTFH), memory cTFH, and B cell subsets. The correlations among cTFH cell subsets and phenotypes, B cell subsets, anti-dsDNA autoantibodies, and clinical parameters were analyzed.ResultsIn subjects with active SLE, cTFH1 and cTFH17 cells were significantly expanded and activated. These expanded cTFH cells expressed memory phenotypes; cTFH1 cells were predominantly central memory (CM) type, while cTFH17 cells were largely effector memory (EM) type. Phenotyping B cell subsets in these patients showed increased frequencies of aNAV and DN2 B cells. Clinically, ICOS+ cTFH1, ICOS+ cTFH17 cells, and SLEDAI-2k scores were found to be correlated. Analysis of cTFH-B cell relationship revealed positive correlations among ICOS+ cTFH1 cells, aNAV B cells, and anti-dsDNA antibodies. Activation of ICOS+ cTFH17 cells was significantly related to the expansion of aNAV and DN2 B cells. The presence of CM cells in cTFH1 and cTFH17 subsets was correlated with aNAV and DN2 B cell frequencies.ConclusionSLE cTFH cells were found to be polarized toward cTFH1 and cTFH17 cells; activation of these cTFH subsets was significantly associated with disease activity score, aNAV, DN2 B cell expansion, and anti-dsDNA antibody level. Thus, the interactions among cTFH1, cTFH17, and B cells likely contribute to the development of autoantibodies and the pathogenesis in SLE.

An IGHG1 variant exhibits polarized prevalence and confers enhanced IgG1 antibody responses against life-threatening organisms.

Evolutionary pressures sculpt population genetics, whereas immune adaptation fortifies humans against life-threatening organisms. How the evolution of selective genetic variation in adaptive immune receptors orchestrates the adaptation of human populations to contextual perturbations remains elusive. Here, we show that the G396R coding variant within the human immunoglobulin G1 (IgG1) heavy chain presents a concentrated prevalence in Southeast Asian populations. We uncovered a 190-kb genomic linkage disequilibrium block peaked in close proximity to this variant, suggestive of potential Darwinian selection. This variant confers heightened immune resilience against various pathogens and viper toxins in mice. Mechanistic studies involving severe acute respiratory syndrome coronavirus 2 infection and vaccinated individuals reveal that this variant enhances pathogen-specific IgG1+ memory B cell activation and antibody production. This G396R variant may have arisen on a Neanderthal haplotype background. These findings underscore the importance of an IGHG1 variant in reinforcing IgG1 antibody responses against life-threatening organisms, unraveling the intricate interplay between human evolution and immune adaptation.

Single-cell and spatial transcriptome analyses reveal tertiary lymphoid structures linked to tumour progression and immunotherapy response in nasopharyngeal carcinoma

Tertiary lymphoid structures are immune cell aggregates linked with cancer outcomes, but their interactions with tumour cell aggregates are unclear. Using nasopharyngeal carcinoma as a model, here we analyse single-cell transcriptomes of 343,829 cells from 77 biopsy and blood samples and spatially-resolved transcriptomes of 31,316 spots from 15 tumours to decipher their components and interactions with tumour cell aggregates. We identify essential cell populations in tertiary lymphoid structure, including CXCL13+ cancer-associated fibroblasts, stem-like CXCL13+CD8+ T cells, and B and T follicular helper cells. Our study shows that germinal centre reaction matures plasma cells. These plasma cells intersperse with tumour cell aggregates, promoting apoptosis of EBV-related malignant cells and enhancing immunotherapy response. CXCL13+ cancer-associated fibroblasts promote B cell adhesion and antibody production, activating CXCL13+CD8+ T cells that become exhausted in tumour cell aggregates. Tertiary lymphoid structure-related cell signatures correlate with prognosis and PD-1 blockade response, offering insights for therapeutic strategies in cancers.

Enhancing the Antibody Production Efficiency of Chinese Hamster Ovary Cells through Improvement of Disulfide Bond Folding Ability and Apoptosis Resistance.

The complex structure of monoclonal antibodies (mAbs) expressed in Chinese hamster ovary (CHO) cells may result in the accumulation of unfolded proteins, triggering endoplasmic reticulum (ER) stress and an unfolded protein response (UPR). If the protein folding ability cannot maintain ER homeostasis, the cell will shut down protein translation and ultimately induce apoptosis. We co-overexpressed HsQSOX1b and survivin proteins in the antibody-producing cell line CHO-PAb to obtain a new cell line, CHO-PAb-QS. Compared with CHO-PAb cells, the survival time of CHO-PAb-QS cells in batch culture was extended by 2 days, and the antibody accumulation and productivity were increased by 52% and 45%, respectively. The proportion of (HC-LC)2 was approximately doubled in the CHO-PAb-QS cells, which adapted to the accelerated disulfide bond folding capacity by upregulating the UPR's strength and increasing the ER content. The results of the apoptosis assays indicated that the CHO-PAb-QS cell line exhibited more excellent resistance to apoptosis induced by ER stress. Finally, CHO-PAb-QS cells exhibited mild oxidative stress but did not significantly alter the redox status. This study demonstrated that strategies based on HsQSOX1b and survivin co-overexpression could facilitate protein disulfide bond folding and anti-apoptosis ability, enhancing antibody production efficiency in CHO cell lines.