ImmunoHorizons最新文献

Our bodies are home to individual-specific microbial ecosystems that have recently been found to be modified by cancer immunotherapies. The interaction between the gut microbiome and islet autoimmunity leading to type I diabetes (T1D) is well described and highlights the microbiome contribution during the onset and T1D development in animals and humans. As cancer immunotherapies induce gut microbiome perturbations and immune-mediated adverse events in susceptible patients, we hypothesized that NOD mice can be used as a predictive tool to investigate the effects of anti-PD-1 treatment on the onset and severity of T1D, and how microbiota influences immunopathology. In this longitudinal study, we showed that anti-PD-1 accelerated T1D onset, increased glutamic acid decarboxylase-reactive T cell frequency in spleen, and precipitated destruction of β cells, triggering high glucose levels and pancreatic islet reduction. Anti-PD-1 treatment also resulted in temporal microbiota changes and lower diversity characteristic of T1D. Finally, we identified known insulin-resistance regulating bacteria that were negatively correlated with glucose levels, indicating that anti-PD-1 treatment impacts the early gut microbiota composition. Moreover, an increase of mucin-degrading Akkermansia muciniphila points to alterations of barrier function and immune system activation. These results highlight the ability of microbiota to readily respond to therapy-triggered pathophysiological changes as rescuers (Bacteroides acidifaciens and Parabacteroides goldsteinii) or potential exacerbators (A. muciniphila). Microbiome-modulating interventions may thus be promising mitigation strategies for immunotherapies with high risk of immune-mediated adverse events.

Compensation or unmixing is essential in analyzing multiparameter flow cytometry data. Errors in data correction, either by compensation or unmixing, can completely change the outcome or mislead the researchers. Owing to limited cell numbers, researchers often use synthetic beads to generate the required single stains for the necessary calculation. In this study, the capacity of synthetic beads to influence data correction is evaluated. Corrected data for human peripheral blood cells were generated using cell-based compensation from the same cells or bead-based compensation to identify differences between the methods. These data suggest that correction with beads on full-spectrum and conventional cytometers does not always follow the basic flow compensation/unmixing expectations and alters the data. Overall, the best approach for bead-based correction for an experiment is to evaluate which beads and fluorochromes are most accurately compensated/unmixed.

Uptake of mRNA vaccines, especially booster immunizations, against COVID-19 has been lower than hoped, perhaps in part due to their reactogenicity. Analgesics might alleviate symptoms associated with vaccination, but they might also impact immune responses. We semiquantitatively measured Ab responses following COVID-19 vaccination in 2354 human participants surveyed about analgesic use after vaccination. Participants who used nonsteroidal anti-inflammatory drugs or acetaminophen after vaccination showed elevated Ab levels against the receptor-binding domain of Spike protein relative to those who did not use analgesics. This pattern was observed for both mRNA-1273 and BNT162b2 and across age groups. Participants who used analgesics more frequently reported fatigue, muscle aches, and headaches than did those who did not use painkillers. Among participants who reported these symptoms, we observed no statistically significant differences in Ab levels irrespective of analgesic use. These data suggest that elevated Ab levels are associated with symptoms and inflammatory processes rather than painkiller use per se. Taken together, we find no evidence that analgesic use reduces Ab responses after COVID-19 vaccination. Recommendation of their use to alleviate symptoms might improve uptake of booster immunizations.

All cells of the immune system reside in adipose tissue (AT), and increasing type 2 immune cells may be a therapeutic strategy to improve metabolic health. In our previous study using i.p. IL-5 injections to increase eosinophils, we observed that a standard vehicle control of 0.1% BSA also elicited profound AT eosinophilia. In this study, we aimed to determine whether BSA-induced AT eosinophilia results in metabolic benefits in murine models of diet-induced obesity. I.p. 0.1% BSA injections increased AT eosinophils after 4 wk. Despite elevating eosinophils to >50% of immune cells in the AT, body weight and glucose tolerance were not different between groups. Interestingly, BSA elicited epithelial IL-33 production, as well as gene expression for type 2 cytokines and IgE production that were dependent on IL-33. Moreover, multiple models of OVA sensitization also drove AT eosinophilia. Following transplantation of a donor fat pad with BSA-induced eosinophilia, OVA-sensitized recipient mice had higher numbers of bronchoalveolar lavage eosinophils that were recipient derived. Interestingly, lungs of recipient mice contained eosinophils, macrophages, and CD8 T cells from the donor AT. These trafficked similarly from BSA- and non-BSA-treated AT, suggesting even otherwise healthy AT serves as a reservoir of immune cells capable of migrating to the lungs. In conclusion, our studies suggest that i.p. injections of BSA and OVA induce an allergic response in the AT that elicits eosinophil recruitment, which may be an important consideration for those using OVA in animal models of allergic disease.

mAbs are highly indispensable tools for diagnostic, prophylactic, and therapeutic applications. The first technique, hybridoma technology, was based on fusion of B lymphocytes with myeloma cells, which resulted in generation of single mAbs against a specific Ag. Along with hybridoma technology, several novel and alternative methods have been developed to improve mAb generation, ranging from electrofusion to the discovery of completely novel technologies such as B cell immortalization; phage, yeast, bacterial, ribosome, and mammalian display systems; DNA/RNA encoded Abs; single B cell technology; transgenic animals; and artificial intelligence/machine learning. This commentary outlines the evolution, methodology, advantages, and limitations of various mAb production techniques. Furthermore, with the advent of next-generation Ab technologies such as single-chain variable fragments, nanobodies, bispecific Abs, Fc-engineered Abs, Ab biosimilars, Ab mimetics, and Ab-drug conjugates, the healthcare and pharmaceutical sectors have become resourceful to develop highly specific mAb treatments against various diseases such as cancer and autoimmune and infectious diseases.

Innate immune cell populations are critical in asthma with different functional characteristics based on tissue location, which has amplified the importance of characterizing the precise number and location of innate immune populations in murine models of asthma. In this study, we performed premortem intravascular (IV) labeling of leukocytes in mice in two models of asthma to differentiate innate immune cell populations within the IV compartment versus those residing in the lung tissue or airway lumen. We performed spectral flow cytometry analysis of the blood, suspensions of digested lung tissue, and bronchoalveolar lavage fluid. We discovered that IV labeled leukocytes do not contaminate analysis of bronchoalveolar lavage fluid but represent a significant proportion of cells in digested lung tissue. Exclusion of IV leukocytes significantly improved the accuracy of the assessments of myeloid cells in the lung tissue and provided important insights into ongoing trafficking in both eosinophilic and neutrophilic asthma models.

Influenza is a highly contagious, acute respiratory disease that causes significant public health and economic threats. Influenza infection induces various inflammatory mediators, IFNs, and recruitment of inflammatory cells in the host. This inflammatory "cytokine storm" is thought to play a role in influenza-induced lung pathogenesis. Empagliflozin is a drug primarily used to lower blood glucose in type II diabetes patients by inhibiting the sodium-glucose cotransporter-2 (SGLT-2) found in the proximal tubules in the kidneys. In this study, we have investigated the effects of empagliflozin on the pulmonary immune response to influenza infection. C57BL/6 mice (wild type) were infected with influenza A/PR/8/34 and treated with empagliflozin, and the disease outcomes were analyzed. Empagliflozin treatment decreased the expression of the inflammatory cytokines IL-1β, IL-6, and CCL2; the percentage of inflammatory monocytes and inducible NO synthase-positive macrophages; and IFN response genes Stat1 and CXCL9 during influenza infection. Further, empagliflozin treatment decreases the expression of IL-6, CCL2, and CCL5 in RAW264.7 macrophages and bone marrow-derived macrophages. However, empagliflozin treatment increased influenza viral titer during infection. Despite fostering an increased viral burden, treatment with empagliflozin decreases the mortality in wild type and high fat diet-induced atherosclerotic LDLR-/- mice. Based on our findings, empagliflozin may have therapeutic implications for use in patients to prevent lung damage and acute respiratory illness.

We previously demonstrated that the upregulation of microRNAs (miRNAs) at the genomic imprinted Dlk1-Dio3 locus in murine lupus is correlated with global DNA hypomethylation. We now report that the Dlk1-Dio3 genomic region in CD4+ T cells of MRL/lpr mice is hypomethylated, linking it to increased Dlk1-Dio3 miRNA expression. We evaluated the gene expression of methylating enzymes, DNA methyltransferases (DNMTs), and demethylating ten-eleven translocation proteins (TETs) to elucidate the molecular basis of DNA hypomethylation in lupus CD4+ T cells. There was a significantly elevated expression of Dnmt1 and Dnmt3b, as well as Tet1 and Tet2, in CD4+ T cells of three different lupus-prone mouse strains compared to controls. These findings suggest that the hypomethylation of murine lupus CD4+ T cells is likely attributed to a TET-mediated active demethylation pathway. Moreover, we found that deletion of early growth response 2 (Egr2), a transcription factor gene in B6/lpr mice markedly reduced maternally expressed miRNA genes but not paternally expressed protein-coding genes at the Dlk1-Dio3 locus in CD4+ T cells. EGR2 has been shown to induce DNA demethylation by recruiting TETs. Surprisingly, we found that deleting Egr2 in B6/lpr mice induced more hypomethylated differentially methylated regions at either the whole-genome level or the Dlk1-Dio3 locus in CD4+ T cells. Although the role of methylation in EGR2-mediated regulation of Dlk1-Dio3 miRNAs is not readily apparent, these are the first data to show that in lupus, Egr2 regulates Dlk1-Dio3 miRNAs, which target major signaling pathways in autoimmunity. These data provide a new perspective on the role of upregulated EGR2 in lupus pathogenesis.

Digital game-based learning has been used to help learners grasp complex concepts in science subjects such as immunology. The aim of this study was to examine whether playing a digital game collaboratively would encourage articulation of scientific terminology and concepts, and whether this would result in learning gains. Forty-seven students at a tertiary institution (17-19 y of age) played a game (n = 22) or watched a video of the game (n = 25) in small groups. This was followed by an activity to document the key learning points. Pretest and posttest results showed that although both groups had learning gains, the game-based learning group outperformed the video group for gains in procedural knowledge, suggesting that playing the game helped students to better internalize the steps involved in the immune response. For the game-based learning group, there was a positive correlation between the number of scientific terms articulated and the gains in the test scores. However, for the video group, there was no correlation. The implications for designing digital game-based learning activities for learning are discussed. The study was carried out in an online environment due to the COVID-19 pandemic mandating home-based learning at the time. The discussion also focuses on how the findings can be applied in an online and face-to-face context.

The oral route is effective and convenient for vaccine administration to stimulate a protective immune response. GALT plays a crucial role in mucosal immune responses, with Peyer's patches (PPs) serving as the primary site of induction. A comprehensive understanding of the structures and functions of these structures is crucial for enhancing vaccination strategies and comprehending disease mechanisms; nonetheless, our current knowledge of these structures in dogs remains incomplete. We performed immunofluorescence and flow cytometry studies on canine PPs to identify cell populations and structures. We also performed single-cell RNA sequencing (scRNA-seq) to investigate the immune cell subpopulations present in PPs at steady state in dogs. We generated and validated an Ab specifically targeting canine M cells, which will be a valuable tool for elucidating Ag trafficking into the GALT of dogs. Our findings will pave the way for future studies of canine mucosal immune responses to oral vaccination and enteropathies. Moreover, they add to the growing body of knowledge in canine immunology, further expanding our understanding of the complex immune system of dogs.