Basophils from allergy to cancer

IgE-Mediated Activation of Mast Cells and Basophils in Health and Disease

Type 2-mediated immune responses protect the body against environmental threats at barrier surfaces, such as large parasites and environmental toxins, and facilitate the repair of inflammatory tissue damage. However, maladaptive responses to typically nonpathogenic substances, commonly known as allergens, can lead to the development of allergic diseases. Type 2 immunity involves a series of prototype TH2 cytokines (IL-4, IL-5, IL-13) and alarmins (IL-33, TSLP) that promote the generation of adaptive CD4+ helper Type 2 cells and humoral products such as allergen-specific IgE. Mast cells and basophils are integral players in this network, serving as primary effectors of IgE-mediated responses. These cells bind IgE via high-affinity IgE receptors (FcεRI) expressed on their surface and, upon activation by allergens, release a variety of mediators that regulate tissue responses, attract and modulate other inflammatory cells, and contribute to tissue repair. Here, we review the biology and effector mechanisms of these cells, focusing primarily on their role in mediating IgE responses in both physiological and pathological contexts.

Adjuvant dendritic cell-based immunotherapy in melanoma: insights into immune cell dynamics and clinical evidence from a phase II trial

BACKGROUND

Dendritic cells (DCs) are the most efficient antigen-presenting cells and play a central role in the immune system, orchestrating immune response against tumors. We previously demonstrated that DC-based vaccination effectively induces anti-tumor immunity, yet at the same time showing a robust safety profile, making this treatment a potential candidate for effective adjuvant immunotherapy. To explore this possibility, we designed a randomized phase II trial (EudraCT no. 2014-005123-27) to provide a complementary autologous DC vaccination to patients (pts) with resected stage III/IV melanoma.

METHODS

Overall, a total of 18 eligible pts were included in this study, 10 of whom received 6 monthly DC vaccination cycles combined with IL-2 administration (arm A), and 8 pts were enrolled in the follow-up observational cohort (arm B). A deep immune biomarkers profiling by multiplex immunoassay, human leukocyte antigens (HLA) typing, multiparametric flow cytometry and in situ tumor microenvironment analysis was performed for the entire pts cohort. The immunological response was assessed in vivo by DTH test and ex vivo against selected melanoma-associated antigens applying the IFN-γ ELISPOT assay.

RESULTS

Pts receiving DC vaccination showed a better relapse-free survival compared to the observational cohort (median 6.6 months, 95% CI, 2.3-not reached (nr) (arm A) vs 5.2 months, 95% CI, 2.5-nr (arm B), not significant), with a favorable trends for female pts (median 15.5 months, 95% CI, 2.6-nr (female) vs 3.3, 95% CI, 2.3-nr (male)), pts with less than 60 years (median 22.5 months, 95% CI, 2.6-nr (age < 60) vs 4.7 months, 95% CI, 2.3-nr (age ≥ 60), and pts with wild-type BRAF status (median 22.5 months, 95% CI, 8.6-nr (BRAF wt) vs 3.8 months, 95% CI, 2.3-nr (BRAF mutated). The toxicity profile was favourable, with no severe adverse events and only mild, manageable reactions. Moreover, additional immune response data suggested increased immune modulation in vaccinated patients, which may reflect a shift in immune dynamics.

CONCLUSIONS

Our findings support the safety and tolerability of DC vaccination as an adjuvant treatment for melanoma, demonstrating significant immune modulation at both the tumor site and peripherally in relapsed and non-relapsed patients. These results highlight the potential of autologous, personalised DC-based therapies and pave the way for the development of innovative immunotherapy combinations in future treatment strategies. Trial registration ClinicalTrials.gov NCT02718391; EudraCT no. 2014-005123-27.

Comparative Insights on IL-5 Targeting with Mepolizumab and Benralizumab: Enhancing EGPA Treatment Strategies

Eosinophilic granulomatosis with polyangiitis (EGPA) is a necrotizing vasculitis characterized by extravascular granulomas and eosinophilia in both blood and tissues. Eosinophils, which play a critical role in the pathophysiology of EGPA, require interleukin (IL)-5 for maturation in the bone marrow and migration to tissues. Glucocorticoids and immunosuppressants have been the cornerstone of treatment; however, their side effects have imposed a significant burden on many patients. Mepolizumab, an antibody that binds to and neutralizes IL-5, demonstrated efficacy in controlling disease activity in EGPA in the MIRRA trial conducted in 2017. In 2024, benralizumab, an IL-5 receptor alpha antagonist, was shown to be non-inferior to mepolizumab in efficacy against EGPA in the MANDARA trial. Both drugs were originally used for severe asthma and have benefited EGPA by reducing eosinophil counts. Due to differences in pharmacological structure and pharmacokinetics, the degree of eosinophil suppression varies between the two agents, and recent studies suggest that they may also affect inflammatory and homeostatic eosinophils differently. This review summarizes the latest insights into the pathophysiology of EGPA, highlights the similarities and differences between the two drugs, and discusses future treatment strategies for EGPA based on current clinical unmet needs, including drug selection.

Utility of the Basophil Reactivity Test in the Clinical Management of People with Severe Uncontrolled Asthma

Introduction

The prognosis of asthma has improved significantly since the availability of monoclonal antibodies (mAbs). However, there are no robust predictive markers of response to help clinicians select one of the multiple biologicals recommended in clinical practice guidelines. The aim of this study was to evaluate the utility of basophil reactivity, measured through the basophil activation test (BAT), as a marker of response to mAbs.

Methods

We measured basophil reactivity, using anti-immunoglobulin E (anti-IgE) antibodies as a stimulus, in 72 consecutive patients with severe uncontrolled asthma before initiation of treatment with mAbs. Forty-nine patients received omalizumab, 28 received mepolizumab, and 23 received benralizumab at some point. The Spanish Asthma Management Guidelines (GEMA) informed clinical management throughout the study. We studied clinical characteristics, laboratory values, and measures of respiratory function and asthma control.

Results

Basophil reactivity (at the highest anti-IgE dilution at which basophil activation was positive) was inversely associated with asthma control and response to any mAb. The patients with higher basophil reactivity (≥ 29% versus < 29%) had lower mAb complete response, more frequent mAb switches, and worse baseline lung function and Asthma Control Test (ACT) scores. The BAT was associated with poor response above the cut-off values of 10.5% for mepolizumab, 15.5% for omalizumab, and 28% for benralizumab.

Conclusion

Patients with basophil reactivity greater than or equal to 29% were less likely to achieve full control of asthma when treated with omalizumab, mepolizumab, or benralizumab, independently of classic clinical or biological markers of type 2 asthma.

Tristetraprolin-mediated mRNA destabilization regulates basophil inflammatory responses

BACKGROUND

Basophils, despite being the least common granulocytes, play crucial roles in type 2 immune responses, such as chronic allergic inflammation and protective immunity against parasites. However, the molecular mechanisms regulating basophil activation and inflammatory molecule production remain poorly understood. Therefore, we investigated the role of RNA-binding proteins, specifically tristetraprolin (TTP), in regulating inflammatory molecule production in basophils.

METHODS

Using antigen/IgE-stimulated basophils from wild-type (WT) and TTP-knockout (TTP-KO) mice, we performed bulk RNA sequencing, transcriptome-wide mRNA stability assays, and protein analyses. We also examined mRNA expression and protein production of inflammatory molecules in TTP-KO basophils under stimulation with IL-33 or LPS. Furthermore, we evaluated the in vivo significance of TTP in basophils using basophil-specific TTP-deficient mice and a hapten oxazolone-induced atopic dermatitis model.

RESULTS

TTP expression was upregulated in basophils following stimulation with antigen/IgE, IL-33, or LPS. Under these stimuli, TTP-KO basophils exhibited elevated mRNA expression of inflammatory molecules, such as Il4, Areg, Ccl3, and Cxcl2, compared to WT basophils. Transcriptome-wide mRNA stability assays revealed that TTP deficiency prolonged the mRNA half-life of these inflammatory mediators. Notably, the production of these inflammatory proteins was significantly increased in TTP-KO basophils. Moreover, basophil-specific TTP-deficient mice showed exacerbated oxazolone-induced atopic dermatitis-like skin allergic inflammation.

CONCLUSIONS

TTP is a key regulator of basophil activation, controlling the production of inflammatory mediators through mRNA destabilization. Our in vivo findings demonstrate that the absence of TTP in basophils significantly aggravates allergic skin inflammation, highlighting its potential as a therapeutic target for allergic diseases.

Airway epithelial cells as drivers of severe asthma pathogenesis

Our understanding of the airway epithelium's role in driving asthma pathogenesis has evolved over time. From being regarded primarily as a physical barrier that could be damaged via inflammation, the epithelium is now known to actively contribute to asthma development through interactions with the immune system. The airway epithelium contains multiple cell types with specialized functions spanning barrier action, mucociliary clearance, immune cell recruitment, and maintenance of tissue homeostasis. Environmental insults may cause direct or indirect injury to the epithelium leading to impaired barrier function, epithelial remodelling, and increased release of inflammatory mediators. In severe asthma, the epithelial barrier repair process is inhibited and the response to insults is exaggerated, driving downstream inflammation. Genetic and epigenetic mechanisms also maintain dysregulation of the epithelial barrier, adding to disease chronicity. Here, we review the role of the airway epithelium in severe asthma and how targeting the epithelium can contribute to asthma treatment.

Basophils induce protumorigenic cytokines from A549 lung adenocarcinoma via mechanisms requiring IgE, galectin-3, and IL-3 priming

Galectin-3 (Gal-3) is implicated in innate immune cell activation in a host of diseases/conditions. We identified a unique response whereby human basophils secrete interleukin (IL)-4/IL-13 when cocultured with A549 cells-lung adenocarcinoma. While displaying parameters consistent with standard IgE-dependent activation, these Gal-3-dependent responses occurred in the absence of specific IgE/allergens and required cell-to-cell contact. We now hypothesize that this mode of activation also impacts A549 function. Our findings show that cytokines are induced in basophil/A549 cocultures that are not detected when either cell is cultured alone, in particular IL-6. As previously shown for IL-4/IL-13, IL-6 production also required cell-to-cell contact and was dependent on A549-Gal-3, as clones deficient of this lectin induced less cytokine. Using culture-derived basophils (CDBAs), we demonstrate that the IL-6 response and production of another tumorigenic factor, vascular endothelial growth factor A (VEGF-A), are induced in CDBA/A549 cocultures but only after passively sensitizing CDBAs with IgE, in a manner similar to IL-4/IL-13. However, IgE-dependent activation of basophils/CDBAs cultured alone failed to induce IL-6/VEGF. Importantly, IL-3-primed basophils, even those fixed with paraformaldehyde, readily induced IL-6/VEGF-A in cocultures, thus verifying that these cytokines are derived from A549. Overall, these results suggest a complex mechanism whereby Gal-3/IgE interactions between IL-3-primed basophils and A549 have the potential to modulate cytokine production by both cells. With Gal-3 implicated not only in many diseases ranging from asthma to cancer, but also in normal physiological conditions, such as wound healing, these findings are predicted to provide insight into the molecular mechanisms by which this lectin (and IgE) functions in these processes.

Immune microenvironment of cancer bone metastasis

Bone is a common and frequent site of metastasis in cancer patients, leading to a significant reduction in quality of life and increased mortality. Bone marrow, the primary site of hematopoiesis, also serves as both a primary and secondary lymphoid organ. It harbors and supports a diverse array of immune cells, thereby creating a distinct immune microenvironment. These immune cells engage in a range of activities, including anti-tumor, pro-tumor, or a combination of both, which influence the development and progression of bone metastases. Rapid advances in cancer immunotherapy have underscored its potential to eradicate bone metastases. However, clinical outcomes have not yet met expectations. To improve the efficacy of immunotherapy, it is crucial to gain a comprehensive and in-depth understanding of the immune microenvironment within bone metastases. This review provides an overview of the current understanding of the role of different immune cells, their anti-tumor and pro-tumor activities, and their overall contribution to bone metastasis.

Association of Circulating Basophil Count with Gastric Cancer Prognosis

PURPOSE

Basophils play a crucial role in immunoglobulin E-mediated allergic reactions and parasitic infections. Recently, a low basophil count was reported to be a poor prognostic indicator in patients with malignant tumors. This study aimed to investigate the cut-off value to evaluate the clinicopathological and prognostic significance of the basophil count in patients with gastric cancer.

METHODS

This study enrolled 1192 gastric cancer patient who underwent surgery without preoperative chemotherapy between 2001 and 2020. The cutoff value was 26/μl based on the receiver of characteristics curves for overall survival, and 606 patients were classified as the low basophil group. The clinicopathological and prognostic significance of the low basophil count was assessed by univariate and multivariate analyses.

RESULTS

Elderly age (p < 0.001), high C-reactive protein level (p < 0.001), low lymphocyte count (p = 0.044), and low neutrophil count (p < 0.001) are independently associated with low basophil count. The low basophil group demonstrated a significantly worse overall survival than the high basophil group (p = 0.005). Although there was no significant difference in stage I, the low basophil group demonstrated poor overall survival in stage II/III/IV. In stage II, low basophil count was independently associated with poor OS. In stage III/IV, low basophil group tended to have poor overall survival rate. Including all stages, low basophil count was an independent risk factor for poor overall survival (hazard ratio (HR) = 1.29, 95% CI: 1.03-1.61, p = 0.027).

CONCLUSION

Low basophil count was significantly associated with elderly age, high C-reactive protein level, and low neutrophil count (<26/μl). In addition, low basophil count was an independent poor prognostic factor in patients with gastric cancer. Thus, preoperative circulating basophil count assessment may be useful for predicting the postoperative survival of patients with gastric cancer.

Basophil-Derived IL-4 Production and Its Potential Pro-Tumoural Role in Th2-Polarisation Within Sentinel Lymph Nodes of Primary Cutaneous Melanoma

Chronic inflammation in the tumour microenvironment (TME) via Th2-polarisation promotes melanoma progression and metastasis, making it a target for immunotherapy. Interleukin (IL)-4 is considered essential for Th2-polarisation in the TME; however, its source remains unknown. Basophils have been postulated as one of its sources. Basophil-derived IL-4 contributes to Th2-polarisation in parasitic infections and allergic diseases and has been implicated in tumour immunity. To identify basophil infiltration into the TME of human melanoma skin lesions and sentinel lymph nodes (SLNs) and demonstrate that basophils produce IL-4. Immunohistochemistry (IHC) with a basophil-specific BB1 antibody and in situ hybridisation. Basophils tended to infiltrate skin lesions at Stage II or later. Higher numbers of infiltrating basophils correlated with the Breslow depth and a shorter progression-free survival, indicating an association with poor prognosis. In SLNs, basophils infiltrated at early stages without metastasis (Stages I and II), with the number of infiltrating basophils being significantly higher in Stage II than in Stage I. IHC revealed that IL-4 levels were also significantly elevated in Stage II SLNs compared to Stage I SLNs. Furthermore, a positive correlation was observed between the number of basophils infiltrating SLNs and IL-4 expression. In situ hybridisation confirmed that basophils expressed IL4. These findings are consistent with previous reports of early-stage melanoma SLNs having a Th2-environment and suggest that basophil-derived IL-4 may contribute to a metastasis-promoting environment in SLNs through Th2-polarisation. Basophils may represent potential immunotherapeutic targets for pro-tumour changes that occur in SLNs in early-stage melanoma.

Machine learning identifies immune-based biomarkers that predict efficacy of anti-angiogenesis-based therapies in advanced lung cancer

BACKGROUND

The anti-angiogenic drugs showed remarkable efficacy in the treatment of lung cancer. Nonetheless, the potential roles of the intra-tumoral immune cell abundances and peripheral blood immunological features in prognosis prediction of patients with advanced lung cancer receiving anti-angiogenesis-based therapies remain unknown. In this study, we aimed to develop an immune-based model for early identification of patients with advanced lung cancer who would benefit from anti-angiogenesis-based therapies.

METHODS

We assembled the real-world cohort of 1058 stage III-IV lung cancer patients receiving the anti-angiogenesis-based therapies. We comprehensively evaluated the tumor immune microenvironment characterizations (CD4, CD8, CD68, FOXP3, and PD-L1) by multiplex immunofluorescence (mIF), as well as calculated the systemic inflammatory index by flow cytometry and medical record review. Based on the light gradient boosting machine (LightGBM) algorithm, a machine-learning model with meaningful parameters was developed and validated in real-world populations.

RESULTS

In the first-line anti-angiogenic therapy plus chemotherapy cohort (n = 385), the intra-tumoral proportion of CD68 + Macrophages and several circulating inflammatory indexes were significantly related to drug response (p < 0.05). Further, neutrophil to lymphocyte ratio (NLR), monocyte to lymphocyte ratio (MLR), the systemic inflammation response index (SIRI), and myeloid to lymphoid ratio (M:L) were identified to construct the non-invasive prediction model with high predictive performance (AUC: 0.799 for treatment response and 0.7006-0.915 for progression-free survival (PFS)). Additionally, based on the unsupervised hierarchical clustering results, the circulating cluster 3 with the highest levels of NLR, MLR, SIRI, and M: L had the worst PFS with the first-line anti-angiogenic therapy plus chemotherapy compared to other circulating clusters (2.5 months, 95 % confidence interval 2.3-2.7 vs. 6.0-9.7 months, 95 % confidence interval 4.9-11.1, p < 0.01). The predictive power of the machine-learning model in PFS was also validated in the anti-angiogenic therapy plus immunotherapy cohort (n = 103), the anti-angiogenic monotherapy cohort (n = 284), and the second-line anti-angiogenic therapy plus chemotherapy cohort (n = 286).

CONCLUSIONS

Integrating pre-treatment circulating inflammatory biomarkers could non-invasively and early forecast clinical outcomes for anti-angiogenic response in lung cancer. The immune-based prognostic model is a promising tool to reflect systemic inflammatory status and predict clinical prognosis for anti-angiogenic treatment in patients with stage III-IV lung cancer.

From the bench to the clinic: basophils and type 2 epithelial cytokines of thymic stromal lymphopoietin and IL-33

Type 2 epithelial cytokines, including thymic stromal lymphopoietin and IL-33, play central roles in modulation of type 2 immune cells, such as basophils. Basophils are a small subset of granulocytes within the leukocyte population that predominantly exist in the blood. They have non-redundant roles in allergic inflammation in peripheral tissues such as the lung, skin and gut, where they increase and accumulate at inflammatory lesions and exclusively produce large amounts of IL-4, a type 2 cytokine. These inflammatory reactions are known to be, to some extent, phenocopies of infectious diseases of ticks and helminths. Recently, biologics related to both type 2 epithelial cytokines and basophils have been approved by the US Food and Drug Administration for treatment of allergic diseases. We summarised the roles of Type 2 epithelial cytokines and basophils in basic science to translational medicine, including recent findings.

On the label-free analysis of white blood cells by holographic quantitative phase imaging flow cytometry

This study presents an innovative methodology to analyze a blood sample from a healthy donor, providing a quantitative characterization of white blood cells (WBCs). It aims to evaluate the effectiveness of holographic quantitative phase imaging (QPI) flow cytometry (FC) in examining phase-contrast maps at the cellular level, thereby enabling the identification and classification of granulocyte types. Additionally, we demonstrate that an unsupervised method can differentiate granulocyte sub-types, i.e., neutrophils and eosinophils. The results instill strong confidence in the potential future use of QPI FC for liquid biopsies and/or for assessing the heterogeneity of WBCs and, more broadly, to facilitate label-free blood tests.

Targeting autophagy: polydatin's role in inducing cell death in AML

Acute myeloid leukemia (AML), a malignant disorder of the hematopoietic system, arises from leukemic stem cells (LSCs) and is the most prevalent form of blood cancer in adults. This study aimed to evaluate the therapeutic potential of polydatin (PD) in AML through ex vivo and in vivo studies, respectively. This study was prompted by PD's novel role in enhancing tumor apoptosis and modulating autophagy. In vitro studies were conducted using the PD-responsive AML cell line KASUMI-1 and found that PD was able to suppress cell proliferation and induce apoptosis by regulating the autophagy pathway. Subsequently, molecular docking was employed to predict the interaction between PD and Autophagy-related protein 5 (ATG5), a key regulator in the autophagy pathway. It was observed that PD inhibited the ubiquitination of ATG5 and enhanced its protein stability, leading to an increase in ATG5 protein levels and subsequent activation of the autophagy pathway (see in Abstract Graphed). The effectiveness and safety of PD in treating AML were confirmed through in vivo experiments using a mouse transplant tumor model, yielding definitive results. Collectively, these results suggest that PD is a promising candidate for the early therapeutic intervention of AML, with a strong potential for clinical application.

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.

NEIL3 Upregulated by TFAP2A Promotes M2 Polarization of Macrophages in Liver Cancer via the Mediation of Glutamine Metabolism

INTRODUCTION

Tumor-associated macrophages, which are part of the tumor microenvironment, are a major factor in cancer progression. However, a complete understanding of the regulatory mechanism of M2 polarization of macrophages (Mø) in liver cancer is yet to be established. This study aimed to investigate the potential mechanism by which NEIL3 influenced M2 Mø polarization in liver cancer.

METHODS

Bioinformatics analysis analyzed NEIL3 expression and its enriched pathways in liver cancer tissue, as well as its correlation with pathway genes. The upstream transcription factor of NEIL3, TFAP2A, was predicted and its expression in liver cancer tissue was analyzed. The binding relationship between the two was analyzed by dual-luciferase reporter and chromatin immunoprecipitation experiments. qRT-PCR assessed NEIL3 and TFAP2A levels in liver cancer cells. Cell viability was detected by CCK-8, while CD206 and CD86 expression was detected by immunofluorescence. IL-10 and CCR2 expressions were assessed using qRT-PCR, and M2 Mø quantity was detected using flow cytometry. Reagent kits tested glutamine (Gln) consumption, α-ketoglutarate, and glutamate content, as well as NADPH/NADP+ and GSH/GSSG ratios. Expression of Gln transport proteins was detected using Western blot. An animal model was established to investigate the influence of NEIL3 expression on liver cancer growth.

RESULTS

NEIL3 was highly expressed in liver cancer and promoted Mø M2 polarization through Gln metabolism. TFAP2A was identified as the upstream transcription factor of NEIL3 and was highly expressed in liver cancer. Rescue experiments presented that overexpression of NEIL3 reversed the suppressive effect of TFAP2A knockdown on Mø M2 polarization in liver cancer. In vivo experiments demonstrated that the knockdown of NEIL3 could significantly repress the growth of xenograft tumors.

CONCLUSION

This study suggested that the TFAP2A/NEIL3 axis promoted Mø M2 polarization through Gln metabolism, providing a theoretical basis for immune therapy targeting the liver cancer TME.

Innate immune cells in tumor microenvironment: A new frontier in cancer immunotherapy

Innate immune cells, crucial in resisting infections and initiating adaptive immunity, play diverse and significant roles in tumor development. These cells, including macrophages, granulocytes, dendritic cells (DCs), innate lymphoid cells, and innate-like T cells, are pivotal in the tumor microenvironment (TME). Innate immune cells are crucial components of the TME, based on which various immunotherapy strategies have been explored. Immunotherapy strategies, such as novel immune checkpoint inhibitors, STING/CD40 agonists, macrophage-based surface backpack anchoring, ex vivo polarization approaches, DC-based tumor vaccines, and CAR-engineered innate immune cells, aim to enhance their anti-tumor potential and counteract cancer-induced immunosuppression. The proximity of innate immune cells to tumor cells in the TME also makes them excellent drug carriers. In this review, we will first provide a systematic overview of innate immune cells within the TME and then discuss innate cell-based therapeutic strategies. Furthermore, the research obstacles and perspectives within the field will also be addressed.

The JAK1/JAK2 inhibitor ruxolitinib inhibits mediator release from human basophils and mast cells

Introduction

The Janus kinase (JAK) family includes four cytoplasmic tyrosine kinases (JAK1, JAK2, JAK3, and TYK2) constitutively bound to several cytokine receptors. JAKs phosphorylate downstream signal transducers and activators of transcription (STAT). JAK-STAT5 pathways play a critical role in basophil and mast cell activation. Previous studies have demonstrated that inhibitors of JAK-STAT pathway blocked the activation of mast cells and basophils.

Methods

In this study, we investigated the in vitro effects of ruxolitinib, a JAK1/2 inhibitor, on IgE- and IL-3-mediated release of mediators from human basophils, as well as substance P-induced mediator release from skin mast cells (HSMCs).

Results

Ruxolitinib concentration-dependently inhibited IgE-mediated release of preformed (histamine) and de novo synthesized mediators (leukotriene C4) from human basophils. Ruxolitinib also inhibited anti-IgE- and IL-3-mediated cytokine (IL-4 and IL-13) release from basophils, as well as the secretion of preformed mediators (histamine, tryptase, and chymase) from substance P-activated HSMCs.

Discussion

These results indicate that ruxolitinib, inhibiting the release of several mediators from human basophils and mast cells, is a potential candidate for the treatment of inflammatory disorders.

Mechanism of intestinal microbiota disturbance promoting the occurrence and development of esophageal squamous cell carcinoma--based on microbiomics and metabolomics

Esophageal squamous cell carcinoma (ESCC) is a high-risk malignant tumor that has been reported in China. Some studies indicate that gut microbiota disorders can affect the occurrence and development of ESCC, but the underlying mechanism remains unclear. In this study, we aimed to explore the possible underlying mechanisms using microbiomics and metabolomics. Fifty ESCC patients and fifty healthy controls were selected as the study subjects according to sex and age, and fecal samples were collected. 16S rDNA sequencing and LC‒MS were used for microbiomics and nontargeted metabolomics analyses. We found significant differences in the composition of the gut microbiota and metabolites between the ESCC patients and control individuals (P < 0.05). ESCC patients exhibited increased abundances of Fusobacteriaceae and Lactobacillus, increased levels of GibberellinA34 and decreased levels of 12-hydroxydodecanoic acid; these metabolites could be diagnostic and predictive markers of ESCC. An increase in the abundance of Enterobacteriaceae and Lactobacillus significantly reduced the content of L-aspartate and pantothenic acid, which may be involved in the occurrence and development of ESCC by downregulating the expression of proteins in the pantothenate and coenzyme A biosynthesis pathways. An imbalance in the intestinal flora may decrease the number of eosinophils in peripheral blood, resulting in the activation of an inflammatory response and immune dysfunction, leading to ESCC deterioration. We hypothesize that this imbalance in the gut microbiota can cause an imbalance in intestinal metabolites, which can activate carcinogenic metabolic pathways, affect inflammation and immune function, and play a role in the occurrence and development of ESCC.

The ontogenesis and heterogeneity of basophils

Basophils are the rarest leukocytes, but they have essential roles in protection against helminths, allergic disorders, autoimmune diseases, and some cancers. For years, the clinical significance of basophils has been neglected because of the lack of proper experimental tools to study them. The development of basophil-specific antibodies and animal models, along with genomic advances like single-cell transcriptomics, has greatly enhanced our understanding of basophil biology. Recent discoveries regarding basophils prompted us to write this review, emphasizing the basophil developmental pathway. In it, we chronologically examine the steps of basophil development in various species, which reveals the apparent advent of basophils predating IgE and basophil's IgE-independent regulatory role in primitive vertebrates. Then, we cover studies of basophil development in adult bone marrow, and compare those of murine and human basophils, introducing newly identified basophil progenitors and mature basophil subsets, as well as the transcription factors that regulate the transitions between them. Last, we discuss the heterogeneity of tissue-resident basophils, which may develop through extramedullary hematopoiesis. We expect that this review will contribute to a deeper understanding of basophil biology from the intricate aspects of basophil development and differentiation, offering valuable insights for both researchers and clinicians.

Matched analysis of detailed peripheral blood and tumor immune microenvironment profiles in bladder cancer

Background: Bladder cancer and therapy responses hinge on immune profiles in the tumor microenvironment (TME) and blood, yet studies linking tumor-infiltrating immune cells to peripheral immune profiles are limited. Methods: DNA methylation cytometry quantified TME and matched peripheral blood immune cell proportions. With tumor immune profile data as the input, subjects were grouped by immune infiltration status and consensus clustering. Results: Immune hot and cold groups had different immune compositions in the TME but not in circulating blood. Two clusters of patients identified with consensus clustering had different immune compositions not only in the TME but also in blood. Conclusion: Detailed immune profiling via methylation cytometry reveals the significance of understanding tumor and systemic immune relationships in cancer patients.

The Role of Gut Microbiota and Leaky Gut in the Pathogenesis of Food Allergy

Food allergy (FA) is a growing public health concern, with an increasing prevalence in Western countries. Increasing evidence suggests that the balance of human gut microbiota and the integrity of our intestinal barrier may play roles in the development of FA. Environmental factors, including industrialization and consumption of highly processed food, can contribute to altering the gut microbiota and the intestinal barrier, increasing the susceptibility to allergic sensitization. Compositional and functional alterations to the gut microbiome have also been associated with FA. In addition, increased permeability of the gut barrier allows the translocation of allergenic molecules, triggering Th2 immune responses. Preclinical and clinical studies have highlighted the potential of probiotics, prebiotics, and postbiotics in the prevention and treatment of FA through enhancing gut barrier function and promoting the restoration of healthy gut microbiota. Finally, fecal microbiota transplantation (FMT) is now being explored as a promising therapeutic strategy to prevent FA in both experimental and clinical studies. In this review article, we aim to explore the complex interplay between intestinal permeability and gut microbiota in the development of FA, as well as depict potential therapeutic strategies.

Hematologic Abnormalities and Diseases Associated with Moderate-to-Marked Basophilia in a Large Cohort of Dogs

Basophilia is a rare hematologic finding in dogs. This research aimed to describe the hematologic and clinical characteristics of dogs with moderate-to-marked basophilia. CBC reports with blood smear examinations from dogs presented to the North Carolina State University Veterinary Teaching Hospital were retrospectively reviewed for basophilia (>193 cells/µL). We classified basophilia as moderate when counts were ≥500 cells/µL and marked when they reached ≥1000 cells/µL. We compared the hematologic and clinical profiles of dogs with moderate-to-marked basophilia (the basophilia group) to those without basophilia, serving as our control group. In addition, we investigated differences between dogs with marked basophilia versus those with moderate basophilia, as well as between dogs in the basophilia group with and without concurrent eosinophilia. Diseases associated with moderate-to-marked basophilia included eosinophilic lung disease (p < 0.0001), leukemia/myeloproliferative neoplasms (p = 0.004), parasitic infection (p = 0.004), mast cell tumor (p = 0.005), and inflammatory bowel disease (p = 0.02). Overall, dogs with marked basophilia had a lower frequency of inflammatory diseases (51% vs. 70%, p = 0.009) and a higher frequency of neoplastic diseases (48% vs. 26%, p = 0.003) compared to those with moderate basophilia. In the basophilia group, concurrent eosinophilia was only seen in 36% of dogs. Dogs with concurrent eosinophilia were more often diagnosed with inflammatory diseases (77% vs. 58%, p = 0.006), with fewer diagnoses of neoplasia (19% vs. 40%, p = 0.001), compared to dogs without concurrent eosinophilia. The findings of this study offer veterinary clinicians valuable guidance in determining diagnostic priorities for dogs with moderate-to-marked basophilia.

Exploiting innate immunity for cancer immunotherapy

Immunotherapies have revolutionized the treatment paradigms of various types of cancers. However, most of these immunomodulatory strategies focus on harnessing adaptive immunity, mainly by inhibiting immunosuppressive signaling with immune checkpoint blockade, or enhancing immunostimulatory signaling with bispecific T cell engager and chimeric antigen receptor (CAR)-T cell. Although these agents have already achieved great success, only a tiny percentage of patients could benefit from immunotherapies. Actually, immunotherapy efficacy is determined by multiple components in the tumor microenvironment beyond adaptive immunity. Cells from the innate arm of the immune system, such as macrophages, dendritic cells, myeloid-derived suppressor cells, neutrophils, natural killer cells, and unconventional T cells, also participate in cancer immune evasion and surveillance. Considering that the innate arm is the cornerstone of the antitumor immune response, utilizing innate immunity provides potential therapeutic options for cancer control. Up to now, strategies exploiting innate immunity, such as agonists of stimulator of interferon genes, CAR-macrophage or -natural killer cell therapies, metabolic regulators, and novel immune checkpoint blockade, have exhibited potent antitumor activities in preclinical and clinical studies. Here, we summarize the latest insights into the potential roles of innate cells in antitumor immunity and discuss the advances in innate arm-targeted therapeutic strategies.

Histamine elevation in familial Mediterranean fever: A study from the Juvenile Inflammatory Rheumatism cohort

BACKGROUND

Familial Mediterranean Fever (FMF) is the most frequent monogenic autoinflammatory disease (AID). Some patients have persistent symptoms despite colchicine intake. Mast cells (MC) are innate immune cells involved in inflammatory conditions including AID. Their activation is responsible for various symptoms such as abdominal pain, bloating and pruritus.

OBJECTIVE

Our objective was to evaluate features of a systemic MC activation in FMF adult patients.

METHODS

FMF adult patients prospectively filled a MC activation survey and usual MC mediators (tryptase and histamine in whole blood, plasma and urine) were measured. They were compared with a healthy control group (HC) and a systemic mastocytosis (SM) group. When digestive biopsies were realized during follow-up, MC infiltration in digestive mucosa was analyzed in FMF, in comparison with SM, Crohn disease (CD) and normal biopsies.

RESULTS

Forty-four FMF patients, 44 HC and 44 SM patients were included. Thirty-one (70%) FMF patients had symptoms of mast cell activation, versus 14 (32%) in the HC group (p = 0.0006). Thirty (68%) FMF patients had at least one elevated MC mediator: mainly whole blood histamine, in 19 (43%) and urinary histamine, in 14 (32%), which were significantly higher than in HC subjects. MC infiltration was comparable in FMF digestive biopsies, biopsies of CD and normal biopsies but was lower than in SM biopsies.

CONCLUSION

FMF patients show frequent symptoms of MC activation and an increase of blood or urinary histamine never described before in this disease. This suggests an implication of MC and possibly basophils in FMF pathophysiology.

Extracellular Vesicles from Immune Cells: A Biomedical Perspective

Research on the role of extracellular vesicles (sEV) in physiology has demonstrated their undoubted importance in processes such as the transportation of molecules with significance for cell metabolism, cell communication, and the regulation of mechanisms such as cell differentiation, inflammation, and immunity. Although the role of EVs in the immune response is actively investigated, there is little literature revising, in a comprehensive manner, the role of small EVs produced by immune cells. Here, we present a review of studies reporting the release of sEV by different types of leukocytes and the implications of such observations on cellular homeostasis. We also discuss the function of immune cell-derived sEV and their relationship with pathological states, highlighting their potential application in the biomedical field.

Prognostic scoring system based on eosinophil- and basophil-related markers for predicting the prognosis of patients with stage II and stage III colorectal cancer: a retrospective cohort study

Background

Systemic inflammation is associated with the prognosis of colorectal cancer (CRC). The current study aimed to construct a comprehensively inflammatory prognostic scoring system named risk score (RS) based on eosinophil- and basophil-related markers and assess its prognostic value in patients with stage II and stage III CRC.

Patients and methods

A total of 3,986 patients were enrolled from January 2007 to December 2013. The last follow-up time was January 2019. They were randomly assigned to the training set and testing set in a 3:2 split ratio. Least absolute shrinkage and selection operator (LASSO)-Cox regression analysis was performed to select the optimal prognostic factors in the construction of RS. The Kaplan-Meier curve, time-dependent receiver operating characteristic (ROC), and Cox analysis were used to evaluate the association between RS and overall survival (OS).

Results

In the training set, all inflammatory markers showed certain prognostic values. Based on LASSO-Cox analysis, nine markers were integrated to construct RS. The Kaplan-Meier curve showed that a higher RS (RS > 0) had a significantly worse prognosis (log-rank p< 0.0001). RS (>0) remained an independent prognostic factor for OS (hazard ratio (HR): 1.70, 95% confidence interval (CI), 1.43-2.03, p< 0.001). The prognostic value of RS was validated in the entire cohort. Time-dependent ROC analysis showed that RS had a stable prognostic effect throughout the follow-up times and could enhance the prognostic ability of the stage by combination. Nomogram was established based on RS and clinicopathological factors for predicting OS in the training set and validated in the testing set. The area under the curve (AUC) values of the 3-year OS in the training and testing sets were 0.748 and 0.720, respectively. The nomogram had a satisfactory predictive accuracy and had better clinical application value than the tumor stage alone.

Conclusions

RS might be an independent prognostic factor for OS in patients with stage II and III CRC, which is helpful for risk stratification of patients. Additionally, the nomogram might be used for personalized prediction and might contribute to formulating a better clinical treatment plan.

Basophils in pruritic skin diseases

Basophils are rare cells in the peripheral blood which have the capability to infiltrate into the skin. Invasion of basophils has been detected in pruritic skin diseases, including atopic dermatitis, bullous pemphigoid, chronic spontaneous urticaria and contact dermatitis. In the skin, basophils are important players of the inflammatory immune response, as they release Th2 cytokines, including interleukin (IL)-4 and IL-13, subsequently inducing the early activation of T-cells. Further, basophils release a multitude of mediators, such as histamine and IL-31, which both play an important role in the initiation of the pruritic response via activation of sensory nerves. Chronic pruritus significantly affects the quality of life and the working capability of patients, though its mechanisms are not fully elucidated yet. Since basophils and neurons share many receptors and channels, bidirectional interaction mechanisms, which drive the sensation of itch, are highlighted in this review.

Basophils beyond allergic and parasitic diseases

Basophils bind IgE via FcεRI-αβγ2, which they uniquely share only with mast cells. In doing so, they can rapidly release mediators that are hallmark of allergic disease. This fundamental similarity, along with some morphological features shared by the two cell types, has long brought into question the biological significance that basophils mediate beyond that of mast cells. Unlike mast cells, which mature and reside in tissues, basophils are released into circulation from the bone marrow (constituting 1% of leukocytes), only to infiltrate tissues under specific inflammatory conditions. Evidence is emerging that basophils mediate non-redundant roles in allergic disease and, unsuspectingly, are implicated in a variety of other pathologies [e.g., myocardial infarction, autoimmunity, chronic obstructive pulmonary disease, fibrosis, cancer, etc.]. Recent findings strengthen the notion that these cells mediate protection from parasitic infections, whereas related studies implicate basophils promoting wound healing. Central to these functions is the substantial evidence that human and mouse basophils are increasingly implicated as important sources of IL-4 and IL-13. Nonetheless, much remains unclear regarding the role of basophils in pathology vs. homeostasis. In this review, we discuss the dichotomous (protective and/or harmful) roles of basophils in a wide spectrum of non-allergic disorders.

Antiallergic Effects of Callerya atropurpurea Extract In Vitro and in an In Vivo Atopic Dermatitis Model

(1) Background: Callerya atropurpurea is found in Laos, Thailand, and Vietnam. Although the anti-inflammatory action of C. atropurpurea has been investigated, the functions of this plant in allergic responses are not understood. Here, we explored the antiallergic mechanism of C. atropurpurea ethanol extract (Ca-EE) using in vitro assays and an in vivo atopic model. (2) Methods: The constituents of Ca-EE were analyzed using GC/MS. Inhibition of lipoxygenase and β-hexosaminidase activity was examined, and the expression of inflammatory genes was measured by quantitative real-time PCR. The regulatory roles of Ca-EE in IgE/FcεRI signaling were examined by Western blotting. The DNCB-induced atopic dermatitis mouse model was performed with histological analysis. (3) Results: Ca-EE comprised cis-raphasatin, lupeol, some sugars, and fatty acids. In RBL-2H3 cells, treatment with Ca-EE significantly reduced the activities of lipoxygenase and β-hexosaminidase, as well as cytokine gene expression. IgE-mediated signaling was downregulated by blocking Lyn kinases. Moreover, Ca-EE effectively inhibited allergic symptoms in the DNCB-induced atopic dermatitis model without toxicity. (4) Conclusions: Ca-EE displayed antiallergic activities through regulating IgE/Lyn signaling in RBL-2H3 cells and a contact dermatitis model. These results indicate that Ca-EE could be effective for allergic disease treatment.