Recruitment Of Immune Cells Research Articles

Transcriptomic profiling of lung fibroblasts in silicosis: Regulatory roles of Nrf2 agonists in a mouse model

Silicosis is an occupational disease caused by long-term inhalation of free silica, resulting in a significant global health burden. Its pathogenesis remains unclear, and there is no effective treatment. Proliferative and activated myofibroblasts play a key role in the development of silicosis. Traditional studies have focused on fibroblast proliferation and collagen secretion, neglecting their functional heterogeneity. With the advancement of omics research, more pathogenic fibroblast subgroups and their functions have been identified. In this study, we applied transcriptomics to analyze gene changes in primary lung fibroblasts during silicosis development using a mouse model. Our results indicate that DEGs are enriched in collagen secretion, ECM synthesis, leukocyte migration, and chemotaxis functions. Altered core genes are associated with immune cell recruitment and cell migration. Nrf2 agonists, known for anti-inflammatory and antioxidant properties, have shown potential therapeutic effects in fibrotic diseases. However, their effects on fibroblasts in silicosis are not fully understood. We used four common Nrf2 agonists to study gene expression changes in lung fibroblasts at the transcriptome level, combined with histopathological and biochemical methods, to investigate their effects on silicosis in mice. Results show that Nrf2 agonists can exert anti-silicosis fibrosis functions by downregulating genes like Fos and Egr1, involved in cell differentiation, proliferation, and inflammation. In conclusion, this study suggests that inflammation-related co-functions of fibroblasts may be a potential mechanism in silicosis pathogenesis. Targeting Nrf2 may be a promising strategy to alleviate oxidative stress and inflammation in silicosis.

An overview of the role of chemokine CX3CL1 (Fractalkine) and CX3C chemokine receptor 1 in systemic sclerosis.

Systemic sclerosis (SSc) is a complex autoimmune disease characterized by fibrosis, vascular damage, and immune dysregulation. Fractalkine or chemokine (C-X3-C motif) ligand 1 (CX3CL1), a chemokine and adhesion molecule, along with its receptor CX3CR1, have been implicated in the inflammatory processes of SSc. CX3CL1 functions as both a chemoattractant and an adhesion molecule, guiding immune cell trafficking. This systematic review examines the role of CX3CL1 and its receptor CX3CR1 in the pathogenesis of SSc, with a focus on pulmonary and vascular complications. A systematic literature search was conducted across databases including PubMed, Scopus, and Web of Science from inception to November 2020. The search focused on studies investigating the CX3CL1/CX3CR1 axis in the context of SSc. The review identified elevated CX3CL1 expression in SSc patients, particularly in the skin and lungs, where CX3CR1 is expressed on infiltrating immune cells. Higher levels of CX3CL1 were correlated with the severity of interstitial lung disease in SSc patients, indicating a potential predictive marker for disease progression. CX3CR1-positive monocytes and NK cells were recruited to inflamed tissues, contributing to fibrosis and tissue damage. Animal studies showed that inhibition of the CX3CL1/CX3CR1 axis reduced fibrosis and improved vascular function. The CX3CL1/CX3CR1 axis plays a key role in immune cell recruitment and fibrosis in SSc. Elevated CX3CL1 levels are associated with lung and vascular complications, making it a potential biomarker for disease progression and a promising therapeutic target.

Impaired unsaturated fatty acid elongation alters mitochondrial function and accelerates metabolic dysfunction-associated steatohepatitis progression

Background and aimsAlthough qualitative and quantitative alterations in liver Polyunsaturated Fatty Acids (PUFAs) are observed in MASH in humans, a causal relationship of PUFAs biosynthetic pathways is yet to be clarified. ELOVL5, an essential enzyme in PUFA elongation regulates hepatic triglyceride metabolism. Nonetheless, the long-term consequences of elongase disruption, particularly in murine models of MASH, have not been evaluated. Approach & resultsIn humans, transcriptomic data indicated that PUFAs biosynthesis enzymes and notably ELOVL5 were induced during MASH progression. Moreover, gene module association determination revealed that ELOVL5 expression was associated with mitochondrial function in both humans and mice. WT and Elovl5-deficient mice were fed a high-fat, high-sucrose (HF/HS) diet for four months. Elovl5 deficiency led to limited systemic metabolic alterations but significant hepatic phenotype was observed in Elovl5−/− mice after the HF/HS diet, including hepatomegaly, pronounced macrovesicular and microvesicular steatosis, hepatocyte ballooning, immune cell infiltration, and fibrosis. Lipid analysis confirmed hepatic triglyceride accumulation and a reshaping of FA profile. Transcriptomic analysis indicated significant upregulation of genes involved in immune cell recruitment and fibrosis, and downregulation of genes involved in oxidative phosphorylation in Elovl5−/− mice. Alterations of FA oxidation and energy metabolism were confirmed by non-targeted metabolomic approach. Analysis of mitochondrial function in Elovl5−/− mice showed morphological alterations, qualitative cardiolipin changes with an enrichment in species containing shorter unsaturated FAs, and decreased activity of I and III respiratory chain complexes. ConclusionEnhanced susceptibility to diet-induced MASH and fibrosis in Elovl5−/− mice is intricately associated with disruptions in mitochondrial homeostasis, stemming from a profound reshaping of mitochondrial lipids, notably cardiolipins.

Does increased CCL2-mediated immune cell recruitment during mucosal BCG vaccination provide superior protection against TB?

Does increased CCL2-mediated immune cell recruitment during mucosal BCG vaccination provide superior protection against TB?

Transcriptomic Analysis of Early-Stage Basal Cell Carcinomas in Murine Skin Following Topical Treatments With Ablative Fractional Laser and Vismodegib.

Recent studies have demonstrated that ablative fractional laser (AFL) can inhibit the hedgehog pathway, enhance immune infiltration and clear basal cell carcinomas (BCCs) in murine models. In this study, we applied RNA sequencing to further characterise the impact of AFL on the transcriptome of murine skin containing early-stage microscopic BCCs, contrasting it with the effects of topical application of the hedgehog inhibitor vismodegib. Our results showed that BCC induction in murine skin was primarily linked to gene upregulation (significantly upregulated genes: 277, significantly downregulated genes: 24). Characterisation of these genes with Ingenuity Pathway Analysis showed that tumour induction was associated with activation of BCC and Sonic Hedgehog signalling. Both AFL and vismodegib treatments reversed these changes, with vismodegib demonstrating superior performance by reversing most of the upregulated genes (AFL: 59/277; vismodegib: 180/277). Surprisingly, Ingenuity Pathway Analysis also revealed that both AFL and vismodegib treatments caused considerable immune cell infiltration. Based on gene set enrichment analysis and cell type deconvolution, AFL treatment resulted in the largest immune cell recruitment, which for both treatments primarily consisted of infiltrating neutrophils, macrophages and monocytes. In conclusion, the distinct effects observed in BCC skin following AFL and vismodegib treatment suggest key differences between the two interventions. Future applications of AFL or vismodegib treatments could leverage their individual effects, for example by combining the effect of AFL on the immune system with other topical treatments.

Targeted recruitment of immune effector cells for rapid eradication of influenza virus infections

Despite much research, considerable data suggest that influenza virus remains a serious health problem because i) the effectiveness of current vaccines ranges only from 19% to 60%, ii) available therapies remain ineffective in advanced stages of disease, iii) death rates vary between 25,000 and 72,000/year in the United States, and iv) avian influenza strains are now being transmitted to dairy cattle that in turn are infecting humans. To address these concerns, we have developed zanDR, a bispecific small molecule that binds and inhibits viral neuraminidase expressed on both free virus and virus-infected cells and recruits naturally occurring anti-rhamnose and anti-dinitrophenyl (DNP) antibodies with rhamnose and DNP haptens. Because the neuraminidase inhibition replicates the chemotherapeutic mechanism of zanamivir and oseltamivir, while rhamnose and DNP recruit endogenous antibodies much like an anti-influenza vaccine, zanDR reproduces most of the functions of current methods of protection against influenza virus infections. Importantly, studies on cells in culture demonstrate that both of the above protective mechanisms remain highly functional in the zanDR conjugate, while studies in lethally infected mice with advanced-stage disease establish that a single intranasal dose of zanDR not only yields 100% protection but also reduces lung viral loads faster and ~1,000× more thoroughly than current antiviral therapies. Since zanDR also lowers secretion of proinflammatory cytokines and protects against virus-induced damage to the lungs better than current therapies, we suggest that combining an immunotherapy with a chemotherapy in single pharmacological agent constitutes a promising approach for treating the more challenging forms of influenza.

The Laws of Attraction: Chemokines as Critical Mediators in Cancer Progression and Immunotherapy Response in Bladder Cancer.

Bladder cancer (BCa) is a prevalent urogenital malignancy, characterized by a myriad of genetic and environmental risk factors that drive its progression. Approximately 75% of bladder tumors are non-muscle-invasive at diagnosis. For such cases, bladder preservation is often feasible with intravesical chemotherapy or immunotherapy. However, the high recurrence rates associated with these tumors necessitate multiple cystoscopic examinations and biopsies, leading to significant financial burden and morbidity. Despite bladder tumors exhibiting one of the highest cancer mutational loads, which typically correlates with improved responses to immunotherapy, challenges persist. The tumor microenvironment serves as a nexus for interactions between tumor cells and the immune system, wherein chemokines and chemokine receptors orchestrate the recruitment of immune cells. This review addresses existing gaps in our understanding of chemokine dynamics in BCa by elucidating the specific roles of key chemokines in shaping the immune landscape of the tumor microenvironment (TME). We explore how dysregulation of chemokine signaling pathways contributes to the recruitment of immunosuppressive cell populations, such as Tregs and monocytes, leading to an unfavorable immune response. Additionally, we highlight the potential of these chemokines as predictive biomarkers for tumor progression and treatment outcomes, emphasizing their role in informing personalized immunotherapeutic strategies. By integrating insights into chemokine networks and their implications for immune cell dynamics, this review seeks to provide a comprehensive understanding of the interplay between chemokines and the immune microenvironment in BCa. Furthermore, we discuss the potential of targeting these chemokine pathways as innovative immunotherapeutic strategies, paving the way for enhanced treatment responses and improved patient outcomes.

Gasdermin C promotes Stemness and Immune Evasion in Pancreatic Cancer via Pyroptosis-Independent Mechanism.

Pancreatic ductal adenocarcinoma (PDAC) is a highly metastatic and lethal disease. Gasdermins are primarily associated with necrosis via membrane permeabilization and pyroptosis, a lytic pro-inflammatory type of cell death. In this study, GSDMC upregulation during PDAC progression is reported. GSDMC directly induces genes related to stemness, EMT, and immune evasion. Targeting Gsdmc in murine PDAC models reprograms the immunosuppressive tumor microenvironment, rescuing the recruitment of anti-tumor immune cells through CXCL9. This not only results in diminished tumor initiation, growth and metastasis, but also enhances the response to KRASG12D inhibition and PD-1 checkpoint blockade, respectively. Mechanistically, it is discovered that ADAM17 cleaves GSDMC, releasing nuclear fragments binding to promoter regions of stemness, metastasis, and immune evasion-related genes. Pharmacological inhibition of GSDMC cleavage or prevention of its nuclear translocation is equally effective in suppressing GSDMC's downstream targets and inhibiting PDAC progression. The findings establish GSDMC as a potential therapeutic target for enhancing treatment response in this deadly disease.

Cholesterol binding to VCAM-1 promotes vascular inflammation.

Hypercholesterolemia has long been implicated in endothelial cell (EC) dysfunction, but the mechanisms by which excess cholesterol causes vascular pathology are incompletely understood. Here we used a cholesterol-mimetic probe to map cholesterol-protein interactions in primary human ECs and discovered that cholesterol binds to and stabilizes the adhesion molecule VCAM-1. We show that accessible plasma membrane (PM) cholesterol in ECs is acutely responsive to inflammatory stimuli and that the nonvesicular cholesterol transporter Aster-A regulates VCAM-1 stability in activated ECs by controlling the size of this pool. Deletion of Aster-A in ECs increases VCAM-1 protein, promotes immune cell recruitment to vessels, and impairs pulmonary immune homeostasis. Conversely, depleting cholesterol from the endothelium in vivo dampens VCAM-1 induction in response to inflammatory stimuli. These findings identify cholesterol binding to VCAM-1 as a key step during EC activation and provide a biochemical explanation for the ability of excess membrane cholesterol to promote immune cell recruitment to the endothelium.

The role of immune cells in the pathogenesis of connective tissue diseases-associated pulmonary arterial hypertension.

Connective tissue diseases-related pulmonary arterial hypertension (CTD-PAH) is a disease characterized by an elevated pulmonary artery pressure that arises as a complication of connective tissue diseases. The number of patients with CTD-PAH accounts for 25.3% of all PAH patients. The main pathological features of CTD-PAH are thickening of intima, media and adventitia of pulmonary arterioles, increased pulmonary vascular resistance, autoimmune activation and inflammatory reaction. It is worth noting that abnormal immune activation will produce autoantibodies and release cytokines, and abnormal immune cell recruitment will promote inflammatory environment and vascular remodeling. Therefore, almost all forms of connective tissue diseases are related to PAH. In addition to general therapy and targeted drug therapy for PAH, high-dose glucocorticoid combined with immunosuppressant can quickly alleviate and stabilize the basic CTD-PAH disease. Given this, the development of therapeutic approaches targeting immune dysregulation and heightened inflammation is recognized as a promising strategy to prevent or reverse the progression of CTD-PAH. This review explores the potential mechanisms by which immune cells contribute to the development of CTD-PAH and examines the clinical application of immunosuppressive therapies in managing CTD-PAH.

PSIV-13 Changes in Interferon-γ and Tumor necrosis factor-α in the vaginal environment of cattle during early gestation

Abstract The embryo must create an immuno-tolerant uterine environment via cytokine signaling to prevent rejection and facilitate embryo attachment. Cytokines have a variety of roles in both reproductive and pregnancy-related processes. Cytokines and chemokines are important in inflammatory pathways for uterine remodeling and recruitment of immune cells during pregnancy. Interferon-γ (INFγ) and tumor necrosis factor-a (TNFα) influence T-helper cell immune responses, which can assist in early pregnancy establishment. Therefore, we hypothesized that INFγ and TNFα concentrations following breeding will be differentially expressed based on mating type, time, and pregnancy outcome. To test this, we completed two experiments in which INFγ and TNFα were quantified in vaginal fluid samples on d 0, d 7, d 14, d 21, d 28, and d 35 following mating. In experiment one, Angus heifers (n = 9) were used to determine cytokine concentrations in the vaginal environment between d 0 to d 35, and between artificial insemination (AI) and natural mating. In experiment 2, lactating dairy cows (n = 88) were used to determine if cytokines could be used as a potential biomarker for successful pregnancy. All vaginal flush samples were collected via Foley catheter in 20 mL of sterile saline. Statistical analysis was completed in SAS 9.4 to determine differences in cytokine concentrations based on day of gestation, mating type, and pregnancy outcome. In experiment 1, vaginal concentrations of TNFα were least (P = 0.05) in AI-bred heifers on d 35 (1.15 ± 2.97 pg/mL) and intermediate in non-pregnant heifers (4.39 ± 2.97 pg/mL) compared with natural service-bred heifers on d 7 (18.09 ± 2.97 pg/mL). INFγ was increased (P = 0.05) on d 7 following natural service (3.86 ± 0.76 pg/mL) compared with AI (0.86 ± 0.76 pg/mL). TNFα was increased (P = 0.02) on d 7 following natural service (18.09 ± 2.89 pg/mL) compared with AI (1.93 ± 2.89 pg/mL) and was increased (P = 0.02) by d 7 after a natural mating compared with a pregnancy resulting from AI mating. In experiment two, concentrations of IFNγ were greater (P = 0.04) on d 7 (1.36 ± 0.57 pg/mL) compared with d 8 (0.24 ± 0.57 pg/mL) of gestation. There was also a tendency for TNFα concentrations to decrease (P = 0.09) from d 7 (60.06 ± 26.94 pg/mL) to d 8 (19.67 ± 26.94 pg/mL) of gestation. In conclusion, concentrations of INFγ and TNFα may not be indicative of a viable embryo or pregnancy outcome but do differ based on day of gestation and mating type, which may aid in understanding the role these cytokines play during early gestation.

Enhancing Anti-Cancer Immune Response by Acidosis-Sensitive Nanobody Display.

One of the main challenges with many cancer immunotherapies is that biomarkers are needed for targeting. These biomarkers are often associated with tumors but are not specific to a particular tumor and can lead to damage in healthy tissues, resistance to treatment, or the need for customization for different types of cancer due to variations in targets. A promising alternative approach is to target the acidic microenvironment found in most solid tumor types. This can be achieved using the pH (Low) Insertion Peptide (pHLIP), which inserts selectively into cell membranes under acidic conditions, sparing healthy tissues. pHLIP has shown potential for imaging, drug delivery, and surface display. For instance, we previously used pHLIP to display epitopes on the surfaces of cancer cells, enabling antibody-mediated immune cell recruitment and selective killing of cancer cells. In this study, we further explored this concept by directly fusing an anti-CD16 nanobody, which activates natural killer (NK) cells, to pHLIP, eliminating the need for antibody recruitment. Our results demonstrated the insertion of pH-sensitive agents into cancer cells, activation of the CD16 receptor on effector cells, and successful targeting and destruction of cancer cells by high-affinity CD16+ NK cells in two cancer cell lines.

Cellular indexing of transcriptomes and epitopes (CITE-Seq) in hidradenitis suppurativa identifies dysregulated cell types in peripheral blood and facilitates diagnosis via machine learning.

Hidradenitis suppurativa (HS) is a chronic inflammatory skin condition characterized by painful nodules, abscesses, and scarring, predominantly affecting intertriginous regions and it is often underdiagnosed. This study aimed to utilize single cell RNA and cell-surface protein sequencing (CITE-Seq) to delineate the immune composition of circulating cells in Hidradenitis suppurativa (HS) peripheral blood compared to healthy controls. CITE-Seq was used to analyze the gene and protein expression profiles of peripheral blood mononuclear cells (PBMCs) from 9 HS and 29 healthy controls. The study identified significant differences cell composition between HS patients and healthy controls, including increased proportions of CD14+ and CD16+ monocytes, cDC2, plasmablasts, and proliferating CD4+ T cells in HS patients. Differential expression analysis revealed upregulation of inflammatory markers such as TNF, IL1B, and NF-κB in monocytes, as well as chemokines and cell adhesion molecules involved in immune cell recruitment and tissue infiltration. Pathway enrichment analysis highlighted the involvement of IL-17, IL-26 and TNF signaling pathways in HS pathogenesis. Machine learning identified key markers for diagnostics and therapeutic development. The findings also support the potential for machine learning models to aid in the diagnosis of HS based on immune cell markers. These insights may inform future therapeutic strategies targeting specific immune pathways in HS.

Chemotherapy drives tertiary lymphoid structures that correlate with ICI-responsive TCF1+CD8+ T cells in metastatic ovarian cancer.

Patients with high-grade serous ovarian carcinoma (HGSOC) are virtually insensitive to immune checkpoint inhibitors (ICIs) employed as standalone therapeutics, at least in part reflecting microenvironmental immunosuppression. Thus, conventional chemotherapeutics and targeted anticancer agents that not only mediate cytotoxic effects but also promote the recruitment of immune effector cells to the HGSOC microenvironment stand out as promising combinatorial partners for ICIs in this oncological indication. We harnessed a variety of transcriptomic, spatial and functional assays to characterize the differential impact of neo-adjuvant paclitaxel-carboplatin on the immunological configuration of paired primary and metastatic HGSOC biopsies as compared to NACT-naïve HGSOC samples from 5 independent patient cohorts. We found neo-adjuvant chemotherapy (NACT)-driven endoplasmic reticulum stress and calreticulin exposure in metastatic HGSOC lesions culminates with the establishment of a dense immune infiltrate including follicular T cells (TFH cells), a prerequisite for mature tertiary lymphoid structure (TLS) formation. In this context, TLS maturation was associated with an increased intratumoral density of ICI-sensitive TCF1+PD-1+ CD8+ T cells over their ICI-insensitive TIM-3+PD-1+ counterparts. Consistent with this notion, chemotherapy coupled with a PD-1-targeting ICI provided a significant survival benefit over either therapeutic approach in syngeneic models of HGSOC bearing high (but not low) tumor mutational burden. Altogether, our findings suggest that NACT promotes TLS formation and maturation in HGSOC lesions, de facto preserving an intratumoral ICI-sensitive T-cell phenotype. These observations emphasize the role of rational design, especially relative to the administration schedule, for clinical trials testing chemotherapy plus ICIs in patients with HGSOC.

Recruitment of CXCR4+ type 1 innate lymphoid cells distinguishes sarcoidosis from other skin granulomatous diseases.

Sarcoidosis is a multiorgan granulomatous disease that lacks diagnostic biomarkers and targeted treatments. Using blood and skin from patients with sarcoid and non-sarcoid skin granulomas, we discovered that skin granulomas from different diseases exhibit unique immune cell recruitment and molecular signatures. Sarcoid skin granulomas were specifically enriched for type 1 innate lymphoid cells (ILC1s) and B cells and exhibited molecular programs associated with formation of mature tertiary lymphoid structures (TLSs), including increased CXCL12/CXCR4 signaling. Lung sarcoidosis granulomas also displayed similar immune cell recruitment. Thus, granuloma formation was not a generic molecular response. In addition to tissue-specific effects, patients with sarcoidosis exhibited an 8-fold increase in circulating ILC1s, which correlated with treatment status. Multiple immune cell types induced CXCL12/CXCR4 signaling in sarcoidosis, including Th1 T cells, macrophages, and ILCs. Mechanistically, CXCR4 inhibition reduced sarcoidosis-activated immune cell migration, and targeting CXCR4 or total ILCs attenuated granuloma formation in a noninfectious mouse model. Taken together, our results show that ILC1s are a tissue and circulating biomarker that distinguishes sarcoidosis from other skin granulomatous diseases. Repurposing existing CXCR4 inhibitors may offer a new targeted treatment for this devastating disease.

MiRNA and mRNA Signatures in Human Acute Kidney Injury Tissue

Acute kidney injury (AKI) is an important contributor to the development of chronic kidney disease (CKD). There is a need to understand molecular mediators that drive recovery and progression to CKD. In particular, the regulatory role of miRNAs in AKI is poorly understood. miRNA and mRNA sequencing were performed on biobanked human kidney tissues obtained in the routine care of subjects with a diagnosis of AKI, minimal change disease (MCD), or without known kidney disease in nephrectomy (Ref) tissue. mRNA analysis revealed that Ref tissues exhibited an injury signature similar to AKI, and not identified in MCD samples. The transcriptomic signature of human AKI was enriched in pathways involved in cell adhesion, epithelial-to-mesenchymal transition, and cell cycle arrest (e.g., CDH6, ITGB6, CDKN1A). In AKI, upregulation of miR-146a, miR-155, miR-142, miR-122 was associated with pathways involved in immune cell recruitment, inflammation, and epithelial-to-mesenchymal transition. miR-122 and miR-146 are associated with downregulation of DDR2 and IGFBP6, genes involved in recovery and progression of kidney disease. These data provide integrated miRNA signatures that complement mRNA and other epigenetic data available in kidney atlases.

Lupus Nephritis: Immune Cells and the Kidney Microenvironment.

Lupus nephritis (LN) is the most common major organ manifestation of the autoimmune disease SLE (lupus), with 10% of those afflicted progressing to ESKD. The kidney in LN is characterized by a significant immune infiltrate and proinflammatory cytokine milieu that affects intrinsic renal cells and is, in part, responsible for the tissue damage observed in LN. It is now increasingly appreciated that LN is not due to unidirectional immune cell activation with subsequent kidney damage. Rather, the kidney microenvironment influences the recruitment, survival, differentiation, and activation of immune cells, which, in turn, modify kidney cell function. This review covers how the biochemical environment of the kidney ( i.e ., low oxygen tension and hypertonicity) and unique kidney cell types affect the intrarenal immune cells in LN. The pathways used by intrinsic renal cells to interact with immune cells, such as antigen presentation and cytokine production, are discussed in detail. An understanding of these mechanisms can lead to the design of more kidney-targeted treatments and the avoidance of systemic immunosuppressive effects and may represent the next frontier of LN therapies.

Activin levels correlate with lymphocytic infiltration in epithelial ovarian cancer.

The TGF-β superfamily member activin, a dimer of the gene products of INHBA and/or INHBB, has been implicated in immune cell maturation and recruitment, but its immune impact within epithelial ovarian cancer (EOC) is not well characterized. We sought to explore differences in activin (INHBA/ Inhibin-βA and INHBB/ Inhibin-βB) between malignant and ovarian tissues at the RNA and protein level and assess the relationship between activin and immune cells in EOC. Publicly available RNA sequencing data were accessed from GEO (#GSE143897) with normalization and quantification performed via DESeq2. Immune gene expression profile was further explored within the TCGA-OV cohort derived from The Cancer Genome Atlas (TCGA). Immunohistochemical analysis was performed to evaluate activin A and T-cell markers CD8 and FoxP3 at the protein level. ELISA to activin-A was used to assess levels in the ascites of advanced EOC patients. Kaplan-Meier curves were generated to visualize survival outcomes. Gene expression levels of components of the activin signaling pathway were elevated within EOC when compared to a benign cohort, with differences in activin type I/II receptor gene profiles identified. Additionally, INHBA gene expression was linked to lymphocytic immune markers in EOC samples. Immunohistochemistry analysis revealed a positive correlation of CD8 and FOXP3 staining with activin A at the protein level in both primary and metastatic epithelial ovarian cancer samples. Furthermore, Activin-A (inhibin-βA) is significantly elevated in EOC patient ascites. INHBA expression is elevated within EOC, correlating with worse survival, with activin protein levels correlating with specific immune infiltration. Our findings suggest that activin-A may play a role in suppressing anti-tumor immunity in EOC, highlighting its potential as a therapeutic target.

O100 IL15RA MEDIATES BLOOD PRESSURE ELEVATION, INFLAMMATION AND VASCULAR DAMAGE IN ANGIOTENSIN II-INDUCED HYPERTENSION

Cytokines are key mediators regulating blood pressure (BP) and target organ damage in hypertension. IL15 levels increase in cardiovascular diseases, but the role of IL15 and its receptor alpha (IL15R) in hypertension and hypertension-mediated inflammation and vascular damage is still unknown. Wild-type and IL15Rα-/-mice (n=5-9) were infused with vehicle or angiotensin II (AngII, 490ng/min/kg). Recombinant IL15 was administered to WT mice (1ug, daily, 14 days) during AngII infusion. Telemetry, wire myography, luminometry, PSR staining, qPCR, immunoblotting, flow cytometry, and primary cell lines were used. Hypertensive patients have increased levels of IL15Rα in arteries, which significantly correlated with systolic (r=0.33, p=0.002), diastolic (r=0.27, p=0.02) pressure and maximal constriction to phenylephrine ex vivo (r=0.27, p=0.03). Similarly, AngII infusion significantly increased serum IL15/IL15Rα (8.8±0.7pg/ml vs 12.1±0.7pg/ml, p<0.01), IL15Rα mRNA (1±0.1 vs 1.8±0.1, p<0.01) and protein (1±0.03 vs 1.8±0.28, p<0.01) levels in the aortas. BP lowering using hydralazine and hydrochlorothiazide treatment prevented these changes in vasculature. IL15Rα was induced by pathophysiological stretch (15%) or interferon-gamma in adventitial fibroblasts, vascular smooth muscles, and endothelial cells in vitro. In contrast, AngII, other inflammatory cytokines or oxidative stress mediators have no such direct effect. Il15Rα-/- blunted AngII-induced hypertension (199±5.6mmHg vs 148±7.3mmHg, p<0.001), protected against endothelial dysfunction (p<0.01) and aortic superoxide production (59.4±7.8 vs 36.4±7.6 RLU/sec/mg) compared to wild-type mice. This was accompanied by reduced perivascular inflammation, lack of immune cell recruitment and effector and memory T cell formation. Similarly, T cell interferon-gamma and interleukin-17 production was attenuated in Il15Rα-/- hypertensive mice. In contrast, simultaneous administration of AngII and rIL15 into WT mice enhanced these outcomes. Perivascular fibrosis was observed in WT, but not Il15Rα-/- hypertensive animals (111036±19117 μm2 vs 48689±5515 μm2, p<0.01) and was in line with significantly lower mRNA of collagen and fibronectin protein levels in Il15Rα-/- aortas. IL15Rα plays a crucial role in immune activation, vascular damage, and AngII-induced hypertension. Targeting this pathway may offer potential therapeutic benefits for controlling hypertension and preventing associated vascular complications.

Sunitinib-induced endocapillary proliferative glomerulonephritis with IgA2 deposit in addition to thrombotic microangiopathy: a case report

BackgroundSunitinib, a multi-targeted tyrosine kinase inhibitor, is used as a second-line therapy for gastrointestinal stromal tumors (GIST) resistant to imatinib. However, its impact on the vascular endothelial growth factor (VEGF) pathway can lead to significant toxicities, including hypertension and thrombotic microangiopathy (TMA).Case presentationThis case report describes a unique instance of a patient with metastatic GIST who developed endocapillary proliferative glomerulonephritis (EPGN) with IgA2 deposits and TMA following sunitinib treatment. The patient presented with severe hypertension, nephrotic syndrome, and acute kidney injury. Renal biopsy confirmed the diagnosis, revealing IgA2 deposits, which are not commonly associated with TMA. Discontinuation of sunitinib led to a rapid improvement in renal function and proteinuria. The potential mechanisms underlying sunitinib-induced glomerular injury may involve the blockade of VEGFR-1, affecting immune cell recruitment and function, and the disruption of the nitric oxide and endothelin systems, leading to endothelial damage and immune dysregulation. Management of these toxicities requires a personalized approach, with options ranging from symptomatic relief to drug discontinuation. The use of endothelin receptor antagonists and other therapeutic alternatives for GIST management is discussed.ConclusionsThis case highlights the complex interplay between the therapeutic effects of sunitinib and its potential renal and cardiovascular toxicities, emphasizing the need for close monitoring and effective management strategies to optimize patient outcomes.