Requirements of IL-4 during the Generation of B Cell Memory

Functional insights of an uncommon hypomorphic variant in IL2RG as a monogenic cause of CVID-like disease with antibody deficiency and T CD4 lymphopenia

Background

Over the last decade, the identification of hypomorphic variants in patients previously diagnosed with Common Variable Immunodeficiency (CVID) has led to the association of milder phenotypes with variants of the IL2RG gene that are usually related to severe combined immunodeficiency. Indeed, several revertant mosaicisms have been described in cases with hypomorphic variants in that gene. Our main objective herein was the functional characterization of p. (Pro58Thr) variant in the IL2RG gene in an adult patient with antibody deficiency and moderate CD4+ T cell lymphopenia.

Methods

Evaluation of the patient included a clinical examination and a complete analysis of the peripheral blood phenotype. To further explore IL2RG functionality we selected downstream signaling readouts, namely STAT3 and STAT5 phosphorylation, NK degranulation and B- and T-cell proliferation capacity in vitro, which can be measured by flow cytometry, that reflect the strength of homeostatic signaling pathways in resting cells and after activation.

Results

The patient presented reduced CD132 expression and conserved T- and B-cell proliferation capacity in vitro. However, we found that intracellular signaling downstream of IL2γc is affected, with reduced STAT3 phosphorylation after IL-21 stimulation in B cells and CD4 T cells. In addition, CD4+ T cells showed a reduced STAT5 phosphorylation in response to IL-2, which was not so evident in CD8+ T cells. NK degranulation was impaired upon PHA and IL-2 as well as plasmablast differentiation in vitro.

Conclusion

We conclude that p. (Pro58Thr) in the IL2RG gene is functionally a hypomorphic variant, as reported previously. Although the functionality of CD8+ is less impaired than the rest of the lymphocyte subsets, we did not detect a reversion of the variant in isolated CD8+, CD4+, CD19+ or NK cells.

Invariant NK T cells counteract HCC metastasis by mediating the migration of splenic CD4+ T cells into the white pulp and infiltration of B cells

Despite significant advances in the diagnosis and treatment of hepatocellular carcinoma (HCC), metastasis and recurrence remain two major obstacles to improving the clinical outcomes for HCC patients. Here, we demonstrate that splenic invariant natural killer T (iNKT) cells can significantly inhibit Hepa1-6-mediated intrahepatic HCC metastasis. Interestingly, in the HCC metastasis model, iNKT deficiency can result in a significant decrease in percentage and absolute number of CD4+ T cell and interleukin-4 level, thus suggesting the involvement of the cross-talk between iNKTs and CD4+ T cells in limiting HCC metastasis to the spleen. Transcriptional signatures of CD4+ T cells following iNKT deficiency displaying impairment of their cell migration function. During HCC metastasis, splenic iNKT rapidly secrete interferon-γ to promote the migration of CD4+ T cells from the marginal zone into the white pulp, thereby triggering subsequent migration of splenic B cells to the liver and exerting anti-tumor immune effects on Hepa1-6 cells. In conclusion, interactions between interferon-γ and its receptor on iNKT and CD4+ T cells can effectively coordinate immune activity between the marginal zone and the white pulp, thereby ultimately inhibiting intrahepatic HCC metastasis. These findings reveal the mechanism underlying the resistance of splenic iNKT to tumor metastasis.

The Detection of COVID-19-Related Multivariate Biomarker Immune Response in Pediatric Patients: Statistical Aspects

The development of new point-of-care diagnostic testing tools for the detection of infectious diseases such as COVID-19 are a key aspect of clinical care and research. Accurate predictive classification methods are required to correctly identify and treat patients. Here, the onset of multisystem inflammatory syndrome in children (MIS-C), a more serious form of COVID-19, was predicted in a pediatric population using a set of multivariate immunological biomarker expression values. A first-stage bivariate detection of statistically significant biomarkers was obtained from a chosen set of standard cytokines and chemokine biomarkers considered relevant to COVID-19-related infection and disease. To incorporate the observed correlation structure among the resulting set of significant biomarkers, dimension reduction was then applied in the form of principal components. A second-stage logistic regression model using a small number of the principal component variables provided a highly predictive classification model for MIS-C. The resulting model was shown to compare favorably with an artificial neural network-based predictive model.

Exploring Asthma as a Protective Factor in COVID-19 Outcomes

Asthma has long been associated with increased susceptibility to viral respiratory infections, leading to significant exacerbations and poorer clinical outcomes. Contrarily and interestingly, emerging data and research surrounding the COVID-19 pandemic have shown that patients with asthma infected with SARS-CoV-2 experienced decreased severity of disease, lower hospitalization rates, as well as decreased morbidity and mortality. Research has shown that eosinophils could enhance immune defense against viral infections, while inhaled corticosteroids can assist in controlling systematic inflammation. Moreover, reduced ACE-2 expression in individuals with asthma may restrict viral entry, and the Th2 immune response may offset the Th1 response typically observed in severe COVID-19 patients. These factors may help explain the favorable outcomes seen in asthmatic patients during the COVID-19 pandemic. This review highlights potential protective mechanisms seen in asthmatic patients, including eosinophilia, the use of inhaled corticosteroids, reduced ACE-2 expression, and a dominate Th2 immune response. Such a study will be helpful to better manage patients with asthma who have contracted COVID-19.

Exploring the therapeutic potential of triterpenoid saponins from Gymnema sylvestre: Mechanistic insights into hepatoprotection, immunomodulation, anticancer activities, molecular docking, and pharmacokinetics

The study comprehensively investigated the therapeutic potential of Gymnema sylvestre triterpenoid saponin extract (GST), encompassing its hepatoprotective, immunomodulatory, and anticancer activities. The study employed a Prednisolone (PRD)-induced immunosuppressed rat model to assess the hepatoprotective and immunomodulatory effects of GST. Using this model, GST was found to modulate haematopoiesis, improving RBC, platelet, and WBC counts, underscoring its potential in hematopoietic homeostasis. Organ atrophy, a hallmark of immunosuppression in spleen, thymus, liver, and kidneys, was reversed with GST treatment, reinforcing its hepatotrophic and organotropic capabilities. Elevated hepatic biomarkers, including alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), and lipid peroxidase (LPO), indicative of hepatocellular injury and oxidative stress, were reduced with GST, underscoring its hepatoprotective and antioxidative effects. Additionally, GST restored depleted antioxidants glutathione (GSH) and superoxide dismutase (SOD), highlighting its strong antioxidative capabilities. Molecular insights revealed a downregulation of interleukin-2 (IL-2) and interleukin-4 (IL-4) mRNA in the spleen of immunosuppressed rats, while GST treatment significantly upregulated IL-2 and IL-4 mRNA expression, showcasing its immunomodulatory potential. Increased levels of tumor necrosis factor-α (TNF-α) associated with immune dysregulation were effectively decreased by GST, underscoring its role in modulating inflammatory responses and restoring immune balance. Molecular docking studies indicated strong inhibition of TNF-α by GST compounds. In terms of anticancer activity, GST demonstrated significant cytotoxicity against MCF-7, and MDA-MB-231 (breast cancer cell lines). Notably, GST demonstrated biocompatibility with normal CHO (Chinese hamster ovary cell line) and HUVEC (Human umbilical vein endothelial cells) cell lines. Molecular docking studies indicated strong inhibition of breast cancer proteins HER1 and HER2 (human epidermal growth factor receptors) by GST compounds. Additionally, pharmacokinetics, bioavailability, drug-likeness, and toxicity risk predictions suggest that GST compounds are pharmacologically favourable with no adverse effects.

Regular cold shower exposure modulates humoral and cell-mediated immunity in healthy individuals

BACKGROUND

Cold hydrotherapy is an ancient practice that has recently gained scientific interest for its potential health benefits. This study explored the effects of regular cold shower exposure on immune cell function.

METHODS

Sixty healthy Egyptian adults were randomized to take cold or hot showers daily for 90 days. Levels of immunoglobulins, cytokines, and interferon-gamma were measured in blood samples at baseline, 30, 60, and 90 days.

RESULTS

The cold shower group exhibited significant increases in immunoglobulin levels. Conversely, the hot shower group showed a significant decrease in IgM levels at 60 and 90 days compared to baseline, alongside nonsignificant decrease of IgG and IgA. the cold shower group demonstrated elevated levels of IL-2 and IL-4 at 90 days, indicating enhanced T-cell proliferation and humoral immunity, respectively. In contrast, the hot shower group did not exhibit significant changes in cytokine levels. There were no significant differences in IFN-γ and TNF-α levels between the groups.

CONCLUSIONS

Regular cold shower exposure appears to enhance humoral and cell-mediated immunity through the upregulation of antibodies, interleukin-2, and interleukin-4. Brief cold stressors may induce physiological adaptations that prime the immune response. This accessible, sustainable lifestyle modification could potentially serve as an alternative therapy to boost immunity. Further research on larger populations is warranted to better understand the physiological effects of cold temperatures on immunity.

Immature B cell homing shapes human lymphoid tissue structure and function

Shortly after the emergence of newly formed human B cells from bone marrow as transitional cells, they diverge along two developmental pathways that can be distinguished by the level of IgM they express and migratory biases. Here, we propose that differential tissue homing of immature B cell subsets contributes to human lymphoid tissue structure and function.

PBMC-engrafted humanized mice models for evaluating immune-related and anticancer drug delivery systems

Immune-related drug delivery systems (DDSs) in humanized mouse models are at the forefront of cancer research and serve as bridges between preclinical studies and clinical applications. These systems offer unique platforms for exploring new therapies and understanding their interactions with human cells and the immune system. Here, we focus on a DDS and a peripheral blood mononuclear cell (PBMC)-engrafted humanized mouse model that we recently developed, and consider some of the key components, challenges, and applications to advance these systems towards better cancer treatment on the basis of a better understanding of the immune response. Our DDS is unique and has a dual function, an anticancer effect and a capacity to fine-tune the immune reaction. The PBL-NOG-hIL-4-Tg mouse system is superior to other available humanized mouse systems for the development of such multifunctional DDSs because it supports the rapid reconstruction of an individual donor's immunity and avoids the onset of graft-versus-host disease.

DNA Vaccines Encoding HTNV GP-Derived Th Epitopes Benefited from a LAMP-Targeting Strategy and Established Cellular Immunoprotection

Vaccines has long been the focus of antiviral immunotherapy research. Viral epitopes are thought to be useful biomarkers for immunotherapy (both antibody-based and cellular). In this study, we designed a novel vaccine molecule, the Hantaan virus (HTNV) glycoprotein (GP) tandem Th epitope molecule (named the Gnc molecule), in silico. Subsequently, computer analysis was used to conduct a comprehensive and in-depth study of the various properties of the molecule and its effects as a vaccine molecule in the body. The Gnc molecule was designed for DNA vaccines and optimized with a lysosomal-targeting membrane protein (LAMP) strategy. The effects of GP-derived Th epitopes and multiepitope vaccines were initially verified in animals. Our research has resulted in the design of two vaccines based on effective antiviral immune targets. The effectiveness of molecular therapies has also been preliminarily demonstrated in silico and in laboratory animals, which lays a foundation for the application of a vaccines strategy in the field of antivirals.

IL-33 Enhances the Total Production of IgG, IgG1, and IgG3 in Angiostrongylus cantonensis-Infected Mice

The purpose of this study is to clarify the role of IL-33 in the immune response to angiostrongyliasis, especially in terms of antibody production and isotype switching. In our experiment, C57BL/6 mice were each infected with 35 infectious larvae and were divided into groups that received an intraperitoneal injection of IL-33, anti-IL-33 monoclonal antibody (mAb), or anti-ST2 mAb 3 days post-infection (dpi) and were subsequently administered booster shots at 5-day intervals with the same dose. Serum samples from each group were collected weekly for ELISA assays. The levels of total IgG, IgG1, and IgG3 were significantly increased in A. cantonensis-infected mice that were treated with IL-33, and the levels decreased significantly in infected groups treated with anti-IL-33 or anti-ST2 mAb. These results suggest that IL-33 may play a critical role in the pathogenesis of human angiostrongyliasis and could be useful for understanding protective immunity against this parasitic infection.

Global IL4Rα blockade exacerbates heart failure after an ischemic event in mice and humans

Ischemic heart failure continues to be a highly prevalent disease among westernized countries and there is great interest in understanding the mechanisms preventing or exacerbating disease progression. The literature suggests an important role for the activation of interleukin-13 or interleukin-4 signaling in improving ischemic heart failure outcomes after myocardial infarction in mice. Dupilumab, a neutralizing antibody that inhibits the shared IL13/IL4 receptor subunit IL4Rα, is widely used for conditions such as ectopic dermatitis in humans. If global depletion of IL4Rα influences ischemic heart failure, either in mice or in humans taking dupilumab, is unknown. Here, we investigated the pathophysiological effects of global IL4Rα genetic deletion in adult mice after surgically induced myocardial infarction (MI). We also determined heart failure risk in patients with ischemic heart disease and concomitant usage of dupilumab using the collaborative patient data network TriNetX. Global deletion of IL4Rα results in exacerbated cardiac dysfunction associated with reduced capillary size after myocardial infarction in mice. In agreement with our findings in mice, dupilumab treatment significantly increased the risk of heart failure development in patients with preexisting diagnosis of ischemic heart disease. Our results indicate that systemic IL4Rα signaling is protective against heart failure development in adult mice and human patients specifically following an ischemic event. Thus, the compelling evidence presented hereby advocates for the development of a randomized clinical trial specifically investigating heart failure development after myocardial ischemia in patients taking dupilumab for another underlying condition.NEW & NOTEWORTHY A body of literature suggests a protective role for IL4Rα signaling postmyocardial infarction in mice. Here, our observational study demonstrates that humans taking the IL4Rα neutralizing antibody, dupilumab, have increased incidence of heart failure following an ischemic event. Similarly, global IL4Rα deletion in mice exacerbates heart failure postinfarct. To our knowledge, this is the first study reporting an adverse association in humans of dupilumab use with heart failure following a cardiac ischemic event.

YF17D-based vaccines - standing on the shoulders of a giant

Live-attenuated yellow fever vaccine (YF17D) was developed in the 1930s as the first ever empirically derived human vaccine. Ninety years later, it is still a benchmark for vaccines made today. YF17D triggers a particularly broad and polyfunctional response engaging multiple arms of innate, humoral and cellular immunity. This unique immunogenicity translates into an extraordinary vaccine efficacy and outstanding longevity of protection, possibly by single-dose immunization. More recently, progress in molecular virology and synthetic biology allowed engineering of YF17D as a powerful vector and promising platform for the development of novel recombinant live vaccines, including two licensed vaccines against Japanese encephalitis and dengue, even in paediatric use. Likewise, numerous chimeric and transgenic preclinical candidates have been described. These include prophylactic vaccines against emerging viral infections (e.g. Lassa, Zika and SARS-CoV-2) and parasitic diseases (e.g. malaria), as well as therapeutic applications targeting persistent infections (e.g. HIV and chronic hepatitis), and cancer. Efforts to overcome historical safety concerns and manufacturing challenges are ongoing and pave the way for wider use of YF17D-based vaccines. In this review, we summarize recent insights regarding YF17D as vaccine platform, and how YF17D-based vaccines may complement as well as differentiate from other emerging modalities in response to unmet medical needs and for pandemic preparedness.

Flublok Quadrivalent Vaccine Adjuvanted with R-DOTAP Elicits a Robust and Multifunctional CD4 T Cell Response That Is of Greater Magnitude and Functional Diversity Than Conventional Adjuvant Systems

It is clear that new approaches are needed to promote broadly protective immunity to viral pathogens, particularly those that are prone to mutation and escape from antibody-mediated immunity. CD4+ T cells, known to target many viral proteins and highly conserved peptide epitopes, can contribute greatly to protective immunity through multiple mechanisms. Despite this potential, CD4+ T cells are often poorly recruited by current vaccine strategies. Here, we have analyzed a promising new adjuvant (R-DOTAP), as well as conventional adjuvant systems AddaVax with or without an added TLR9 agonist CpG, to promote CD4+ T cell responses to the licensed vaccine Flublok containing H1, H3, and HA-B proteins. Our studies, using a preclinical mouse model of vaccination, revealed that the addition of R-DOTAP to Flublok dramatically enhances the magnitude and functionality of CD4+ T cells specific for HA-derived CD4+ T cell epitopes, far outperforming conventional adjuvant systems based on cytokine EliSpot assays and multiparameter flow cytometry. The elicited CD4+ T cells specific for HA-derived epitopes produce IL-2, IFN-γ, IL-4/5, and granzyme B and have multifunctional potential. Hence, R-DOTAP, which has been verified safe by human studies, can offer exciting opportunities as an immune stimulant for next-generation prophylactic recombinant protein-based vaccines.

From neglect to spotlight: the underappreciated role of B cells in cutaneous inflammatory diseases

The skin, covering our entire body as its largest organ, manifests enormous complexities and a profound interplay of systemic and local responses. In this heterogeneous domain, B cells were considered strangers. Yet, recent studies have highlighted their existence in the skin and their distinct role in modulating cutaneous immunity across various immune contexts. Accumulating evidence is progressively shedding light on the significance of B cells in maintaining skin health and in skin disorders. Herein, we integrate current insights on the systemic and local contributions of B cells in three prevalent inflammatory skin conditions: Pemphigus Vulgaris (PV), Systemic Lupus Erythematosus (SLE), and Atopic Dermatitis (AD), underscoring the previously underappreciated importance of B cells within skin immunity. Moreover, we address the potential adverse effects of current treatments used for skin diseases, emphasizing their unintentional consequences on B cells. These comprehensive approaches may pave the way for innovative therapeutic strategies that effectively address the intricate nature of skin disorders.

Immunogenicity of biologics used in the treatment of asthma

OBJECTIVE

Asthma is a major global disease affecting adults and children, which can lead to hospitalization and death due to breathing difficulties. Although targeted monoclonal antibody therapies have revolutionized treatment of severe asthma, some patients still fail to respond. Here we critically evaluate the literature on biologic therapy failure in asthma patients with particular reference to anti-drug antibody production, and subsequent loss of response, as the potential primary cause of drug failure in asthma patients.

RECENT FINDINGS

Encouragingly, asthma in most cases responds to treatment, including the use of an increasing number of biologic drugs in moderate to severe disease. This includes monoclonal antibody inhibitors of immunoglobulin E and cytokines, including interleukin 4, 5, or 13 and thymic stromal lymphopoietin. These limit mast cell and eosinophil activity that cause the symptomatic small airways obstruction and exacerbations.

SUMMARY

Despite humanization of the antibodies, it is evident that benralizumab; dupilumab; mepolizumab; omalizumab; reslizumab and tezepelumab all induce anti-drug antibodies to some extent. These can contribute to adverse events including infusion reactions, serum sickness, anaphylaxis and potentially disease activity due to loss of therapeutic function. Monitoring anti-drug antibodies (ADA) may allow prediction of future treatment-failure in some individuals allowing treatment cessation and switching therefore potentially limiting disease breakthrough.

Wild Rosa roxburghii Tratt Juices Grown at Different Altitudes Regulate Blood Glucose in Type 1 Diabetic Mice via the PI3K/Akt Pathway

To explore hypoglycemic effect of wild Rosa roxburghii tratt (RRT) juice at different altitudes on type 1 diabetes mellitus (T1DM). The T1DM mouse model was induced by streptozotocin (STZ), and the experiment included a normal group (NC), model group (MC), wild RRT juice groups high (HF), medium (MF), low altitude (DF) and cultivated control group (PC). During experiment, food intake, water intake, body weight, and fasting blood glucose were measured. After 28 days of administration, glucose tolerance, glycogen level, lipid profiles, and antioxidation levels in serum and liver were measured, and histomorphological changes of liver and kidney were observed by hematoxylin and eosin staining. The results showed that wild RRT juice reduced blood glucose level, alleviated liver and kidney tissue damage, improved glucose and lipid metabolism disorders and attenuated oxidative damage in T1DM mice. Western blot showed that wild RRT juice at grown at different altitudes significantly increased protein abundance of PI3K, Akt, and GLUT2 in liver of T1DM mice. In conclusion, wild RRT juice from different altitudes improved glucose and lipid metabolism disorders and oxidative damage in T1DM mice, which may be attributed to activation of PI3K/Akt pathway. Overall effect: MF > PC > HF > DF.