Expression Of Adhesion Molecules Research Articles

Neutrophil extracellular traps potentiate effector T cells via endothelial senescence in uveitis.

Autoimmune uveitis (AU) is a sight-threatening ocular autoimmune disorder that often manifests as retinal vasculitis. Increased neutrophil infiltration around retinal vessels has been reported during the progression of AU, while how they function is not fully recognized. Neutrophil extracellular traps (NETs), produced by activated neutrophils, have been suggested to be detrimental in autoimmune diseases. Here, we found that NETs were elevated in patients with active AU, and this was verified in an experimental AU (EAU) mouse model. Depletion of neutrophils or degradation of NETs with deoxyribonuclease-I (DNase I) could decrease CD4+ effector T cell (Teff) infiltration in retina and spleen to alleviate EAU. Moreover, we found that the expression of adhesion molecules, selectin, and antigen-presenting molecules was elevated in EAU retina and in retinal microvascular endothelial cells (RMECs) cocultured with NETs. The stimulated RMECs further facilitated CD4+ T cell adhesion, activation, and differentiation into Teffs. Mechanistically, NETs trigger RMEC activation by hastening cell senescence through the cyclic GMP-AMP synthase (cGAS)/stimulator of interferon genes (STING) pathway. Slowing down senescence or inhibiting the cGAS/STING pathway in RMECs reduces the activation and differentiation of CD4+ T cells. These results suggest a deleterious role of NETs in AU. Targeting NETs would offer an effective therapeutic method.

Hepatic Abnormal Secretion of Apolipoprotein C3 Promotes Inflammation in Aortic Dissection.

Apolipoprotein C3 (apo C3) is primarily secreted by the liver and is involved in promoting sterile inflammation and organ damage under pathological conditions. Previous studies have shown that apo C3 is abundant in the plasma exosomes of patients with aortic dissection (AD), but its specific role in AD remains unclear. In vivo, adeno-associated virus was used to knock down hepatic apo C3 expression in an AD mouse model to assess the impact of liver-derived apo C3 on the development of AD. Invitro, recombinant apo C3 protein was added to the culture medium of J774A.1 macrophages to evaluate its effect on macrophage polarization and to identify the underlying mechanisms. Additionally, the effect of apo C3 on the function of aortic endothelial and smooth muscle cells was explored. Apo C3 in the aortas of AD mice was found to originate from abnormal hepatic secretion, which enters the bloodstream and subsequently deposits in the aorta. Adeno-associated virus-mediated hepatic apo C3 knockdown significantly reduced AD incidence (P=0.0036), macrophage infiltration (P=0.0004), and collagen deposition in the aorta (P=0.0016). Similarly, inhibiting the apo C3 receptor Toll-like receptor 2 significantly lowered AD incidence (P=0.0352). Invitro, recombinant apo C3 protein promoted M1 polarization and matrix metalloproteinase secretion in macrophages by activating the Toll-like receptor 2/NLR family pyrin domain containing 3 pathway. Additionally, apo C3 increased adhesion molecule expression in endothelial cells and induced inflammation, chemotaxis, and apoptosis in vascular smooth muscle cells. Our findings highlight the role of abnormally secreted hepatic apo C3 in promoting aortic inflammation.

P0068 Distribution of α4β7 integrin and MAdCAM-1 expression according to the location of intestinal inflammation in a murine model of spontaneous chronic enterocolitis

Abstract Background The selective blockade of α4β7 integrin is a treatment for inflammatory bowel disease (IBD), with different efficacy according to the location of inflammation along the gastrointestinal tract. A more pronounced effect has been reported in patients with predominant colonic inflammation. It may be attributed to differences in the regional expression of adhesion molecules. This study aimed to investigate the expression of α4β7 integrin and mucosal addressin cell adhesion molecule-1 (MAdCAM-1) in colon, ileum, and mesentery, using IL-10 knockout (KO) mice as a model of spontaneous chronic enterocolitis. Methods At 20 weeks, the colon, ileum, and mesentery were extracted from IL-10KO and C57BL/6 wild-type (WT) mice. Protein levels of α4β7 integrin and MAdCAM-1 were determined by Western blot in the different tissues. Additionally, pro-inflammatory cytokines (TNF-α and IFN-γ) and epithelial adhesion molecules (Zonula Occludens-1, ZO-1; E-cadherin and Mucin 2, Muc2) expression in the ileum, as well as adiponectin expression in the mesentery, were analyzed using real-time PCR. Results Analysis demonstrated a significant increase in gene expression of the pro-inflammatory cytokines TNF-α and IFN-γ in the ileum of IL-10 KO mice compared with WT mice (p<0.01). In addition, IL-10KO mice exhibited reduced expression of ZO-1, E-cadherin, and Muc2 in the ileum relative to WT mice (p<0.001). IL-10 deficiency also led to a marked decrease in adiponectin expression in the mesentery (p<0.05). We then analyzed the protein level of MAdCAM-1 and α4β7 integrin according to anatomic region. Remarkably, the protein analysis revealed significantly higher levels of MAdCAM-1 (p<0.01) and α4β7 integrin (p<0.05) in the colon of IL-10 KO mice compared to WT. In the ileum, while MAdCAM-1 levels remained unchanged, α4β7 integrin expression was increased in IL-10KO mice (p<0.01). No significant differences in MAdCAM-1 or α4β7 integrin levels were observed in the mesentery between IL-10KO and WT mice Conclusion IL-10-deficient mice develop inflammation in the ileum, accompanied by a reduction in adiponectin production in the mesentery. In this setting, both α4β7 integrin and MAdCAM-1 showed increased expression in the colon, which was not observed in the ileum or mesentery, despite the inflammation. This differential regional expression pattern of adhesion molecules may explain the variation in the efficacy of anti-integrin therapies. Characterizing these patterns in patients with IBD could help identify those who would benefit most from these treatments.

Lung endothelial cell senescence impairs barrier function and promotes neutrophil adhesion and migration.

Cellular senescence contributes to inflammation and organ dysfunction during aging. While this process is generally characterized by irreversible cell cycle arrest, its morphological features and functional impacts vary in different cells from various organs. In this study, we examined the expression of multiple senescent markers in the lungs of young and aged humans and mice, as well as in mouse lung endothelial cells cultured with a senescence inducer, suberoylanilide hydroxamic acid (SAHA), or doxorubicin (DOXO). We detected increased levels of p21, γH2AX, and SA-β-Gal and decreased Ki-67 and Lamin B1 in aged lungs and senescent lung endothelial cells. Importantly, the expression of senescent markers was associated with an inflammatory response in aged mouse lungs characterized by neutrophil infiltration, increased expression of intercellular adhesion molecule 1 (ICAM-1), and decreased protein levels of VE-cadherin and ZO-1. As the latter two are critical constituents of endothelial cell-cell junctions, we hypothesized that their decreased expression could lead to compromised junction barrier integrity. Indeed, senescent endothelial cells (ECs) exhibited impaired barrier properties, as measured by increased permeability to solutes of small size (3-kD) and albumin (70-kD). When co-cultured with neutrophils, senescent ECs and their supernatant promoted neutrophil chemotaxis and trans-endothelial migration. Taken together, our results suggest that lung EC senescence weakens cell-cell junctions, impairs barrier function, and promotes neutrophil adhesion and migration, which may contribute to the development of inflammation and related pathologies in the lungs during aging.

Neutrophil adhesion to vessel walls impairs pulmonary circulation in COVID-19 pathology

Microthrombus formation is associated with COVID-19 severity; however, the detailed mechanism remains unclear. In this study, we investigated mouse models with severe pneumonia caused by SARS-CoV-2 infection by using our in vivo two-photon imaging system. In the lungs of SARS-CoV-2-infected mice, increased expression of adhesion molecules in intravascular neutrophils prolonged adhesion time to the vessel wall, resulting in platelet aggregation and impaired lung perfusion. Re-analysis of scRNA-seq data from peripheral blood mononuclear cells from COVID-19 cases revealed increased expression levels of CD44 and SELL in neutrophils in severe COVID-19 cases compared to a healthy group, consistent with our observations in the mouse model. These findings suggest that pulmonary perfusion defects caused by neutrophil adhesion to pulmonary vessels contribute to COVID-19 severity.

Endothelial-Ercc1 DNA repair deficiency provokes blood-brain barrier dysfunction

Aging of the brain vasculature plays a key role in the development of neurovascular and neurodegenerative diseases, thereby contributing to cognitive impairment. Among other factors, DNA damage strongly promotes cellular aging, however, the role of genomic instability in brain endothelial cells (EC) and its potential effect on brain homeostasis is still largely unclear. We here investigated how endothelial aging impacts blood-brain barrier (BBB) function by using excision repair cross complementation group 1 (ERCC1)-deficient human brain ECs and an EC-specific Ercc1 knock out (EC-KO) mouse model. In vitro, ERCC1-deficient brain ECs displayed increased senescence-associated secretory phenotype expression, reduced BBB integrity, and higher sprouting capacities due to an underlying dysregulation of the Dll4-Notch pathway. In line, EC-KO mice showed more P21+ cells, augmented expression of angiogenic markers, and a concomitant increase in the number of brain ECs and pericytes. Moreover, EC-KO mice displayed BBB leakage and enhanced cell adhesion molecule expression accompanied by peripheral immune cell infiltration into the brain. These findings were confined to the white matter, suggesting a regional susceptibility. Collectively, our results underline the role of endothelial aging as a driver of impaired BBB function, endothelial sprouting, and increased immune cell migration into the brain, thereby contributing to impaired brain homeostasis as observed during the aging process.

Tissue-resident memory T cells in diseases and therapeutic strategies.

Tissue-resident memory T (TRM) cells are crucial components of the immune system that provide rapid, localized responses to recurrent pathogens at mucosal and epithelial barriers. Unlike circulating memory T cells, TRM cells are located within peripheral tissues, and they play vital roles in antiviral, antibacterial, and antitumor immunity. Their unique retention and activation mechanisms, including interactions with local epithelial cells and the expression of adhesion molecules, enable their persistence and immediate functionality in diverse tissues. Recent advances have revealed their important roles in chronic inflammation, autoimmunity, and cancer, illuminating both their protective and their pathogenic potential. This review synthesizes current knowledge on TRM cells' molecular signatures, maintenance pathways, and functional dynamics across different tissues. We also explore the interactions of TRM cells with other immune cells, such as B cells, macrophages, and dendritic cells, highlighting the complex network that underpins the efficacy of TRM cells in immune surveillance and response. Understanding the nuanced regulation of TRM cells is essential for developing targeted therapeutic strategies, including vaccines and immunotherapies, to enhance their protective roles while mitigating adverse effects. Insights into TRM cells' biology hold promise for innovative treatments for infectious diseases, cancer, and autoimmune conditions.

Uncovering the Role of ALDH1A2 in Prostate Cancer: Insights from Genetic and Expression Analyses.

Biochemical recurrence (BCR) is a critical concern in prostate cancer management; however, its underlying genetic determinants remain poorly understood. The aldehyde dehydrogenase 1 (ALDH1) gene family is involved in cellular detoxification and biosynthetic processes and has been implicated in various cancers. This study investigated the association between the ALDH1 family members and prostate cancer recurrence. We conducted a two-stage genetic association study involving 134 single-nucleotide polymorphisms within the ALDH1 family to assess their association with BCR-free survival in prostate cancer. Gene set and pathway enrichment analyses were performed to explore the biological relevance of significant genes across multiple datasets. ALDH1A2 rs16939929 showed a robust association with BCR-free survival in both discovery and replication cohorts. Functional analyses indicated that rs16939929 affected ALDH1A2 expression in various tissues. Pooled analysis of 42 prostate cancer gene expression datasets revealed that ALDH1A2 expression was significantly lower in prostate cancer tissues and higher expression was associated with better patient prognosis. Enrichment analyses revealed that ALDH1A2 was co-expressed with genes primarily involved in cell adhesion pathways. Further analysis confirmed that several of these co-expressed cell adhesion molecules were associated with improved patient survival. In addition, ALDH1A2 expression was associated with increased immune cell infiltration into the prostate cancer microenvironment. In conclusion, ALDH1A2 rs16939929 is a significant predictor of BCR-free survival in prostate cancer, potentially through its effects on the gene expressions of ALDH1A2 and cell adhesion molecules. These findings suggest that ALDH1A2 plays a tumor-suppressive role in prostate cancer progression.

CD93 blockade promotes effector T-cell infiltration and facilitates adoptive cell therapy in solid tumors

BackgroundAdaptive cellular therapy (ACT), particularly chimeric antigen receptor (CAR)-T cell therapy, has been successful in the treatment of hemopoietic malignancies. However, poor trafficking of administered effector T cells to the...

Annexin A8 deficiency delays atherosclerosis progression.

Atherosclerosis is a chronic inflammatory disease characterized by the accumulation of lipids and leukocytes within the arterial wall. By studying the aortic transcriptome of atherosclerosis-prone apolipoprotein E (ApoE-/-)mice, we aimed to identify novel players in the progression of atherosclerosis. RNA-Seq analysis was performed on aortas from ApoE-/- and wild-type mice. AnxA8 expression was assessed in human and mice atherosclerotic tissue and healthy aorta. ApoE-/- mice lacking systemic AnxA8 (ApoE-/-AnxA8-/-) were generated to assess the effect of AnxA8 deficiency on atherosclerosis. Bone marrow transplantation (BMT) was also performed to generate ApoE-/- lacking AnxA8 specifically in bone marrow-derived cells. Endothelial-specific AnxA8 silencing in vivo was performed in ApoE-/- mice. The functional role of AnxA8 was analysed in cultured murine cells. RNA-Seq unveiled AnxA8 as one of the most significantly upregulated genes in atherosclerotic aortas of ApoE-/- compared to wild-type mice. Moreover, AnxA8 was upregulated in human atherosclerotic plaques. Germline deletion of AnxA8 decreased the atherosclerotic burden, the size and volume of atherosclerotic plaques in the aortic root. Plaques of ApoE-/-AnxA8-/- were characterized by lower lipid and inflammatory content, smaller necrotic core, thicker fibrous cap and less apoptosis compared with those in ApoE-/-AnxA8+/+. BMT showed that hematopoietic AnxA8 deficiency had no effect on atherosclerotic progression. Oxidized low-density lipoprotein (ox-LDL) increased AnxA8 expression in murine aortic endothelial cells (MAECs). In vitro experiments revealed thatAnxA8 deficiency in MAECs suppressed P/E-selectin and CD31 expression and secretion induced by ox-LDL with a concomitant reduction in platelet and leukocyte adhesion. Intravital microscopy confirmed the reduction in leukocyte and platelet adhesion in ApoE-/-AnxA8-/- mice. Finally, endothelial-specific silencing of AnxA8 decreased atherosclerosis progression. Our findings demonstrate that AnxA8 promotes the progression of atherosclerosis by modulating endothelial-leukocyte interactions. Interventions capable of reducing AnxA8 expression in endothelial cells may delay atherosclerotic plaque progression. This study shows that AnxA8 is upregulated in aorta of atheroprone mice and in human atherosclerotic plaques. Germline AnxA8 deficiency reduces platelet and leukocyte recruitment to activated endothelium as well as atherosclerotic burden, plaque size, and macrophage accumulation in mice. AnxA8 regulates oxLDL-induced adhesion molecules expression in aortic endothelial cells. Our data strongly suggest that AnxA8 promotes disease progression through regulation of adhesion and influx of immune cells to the intima. Endothelial specific silencing of AnxA8 reduced atherosclerosis progression. Therapeutic interventions to reduce AnxA8 expression may delay atherosclerosis progression.

Analysis of Light-Controlled Artificial Cell-Cell Adhesions.

The precise spatial and temporal regulation of cell-cell adhesions is crucial for understanding the underlying biological processes and for assembling multicellular structures in tissue engineering. Traditional approaches have relied on chemical membrane functionalization and regulated gene expression of native cell adhesion molecules (CAMs), but these methods lack the necessary control and can be detrimental to cells. In contrast, engineered photoswitchable cell-cell adhesions offer a reversible and dynamic regulation at a single-cell resolution. This is achieved by expressing different photodimerizers as artificial CAMs on the cell surfaces. Here, we describe a straightforward method for the functional analysis of these photoswitchable cell-cell adhesions in a 3D suspension culture.

QSP Modeling Shows Pathological Synergism Between Insulin Resistance and Amyloid-Beta Exposure in Upregulating VCAM1 Expression at the BBB Endothelium.

Type 2 diabetes mellitus (T2DM), characterized by insulin resistance, is closely associated with Alzheimer's disease (AD). Cerebrovascular dysfunction is manifested in both T2DM and AD, and is often considered as a pathological link between the two diseases. Insulin signaling regulates critical functions of the blood-brain barrier (BBB), and endothelial insulin resistance could lead to BBB dysfunction, aggravating AD pathology. However, insulin signaling is intrinsically dynamic and involves interactions among numerous molecular mediators. Hence, a mechanistic systems biology model is needed to understand how insulin regulates BBB physiology and the consequences of its impairment in T2DM and AD. In this study, we investigated the pharmacodynamic effect of insulin on the expression of vascular cell adhesion molecule 1 (VCAM1), a marker of cerebrovascular inflammation. Intriguingly, normal insulin concentrations selectively activated the PI3K-AKT pathway, leading to decreased VCAM1 expression. However, exposure to supraphysiological insulin levels, which is present in insulin resistance, activated both PI3K-AKT and MEK-ERK pathways, and increased VCAM1 expression. We developed a mathematical model that adequately described the dynamics of various insulin signaling nodes and VCAM1 expression. Further, the model was integrated with invitro proteomics and transcriptomics data from AD patients to simulate VCAM1 expression under pathological conditions. This approach allowed us to establish a quantitative systems pharmacology framework to investigate BBB dysfunction in AD and metabolic syndrome, thereby offering opportunities to identify specific disruptions in molecular networks that will enable us to identify novel therapeutic targets.

Prostanoid signaling in retinal cells elicits inflammatory responses relevant to early-stage diabetic retinopathy

AbstractInflammation is a critical driver of the early stages of diabetic retinopathy (DR) and offers an opportunity for therapeutic intervention before irreversible damage and vision loss associated with later stages of DR ensue. Nonsteroidal anti-inflammatory drugs (NSAIDs) have shown mixed efficacy in slowing early DR progression, notably including severe adverse side effects likely due to their nonselective inhibition of all downstream signaling intermediates. In this study, we investigated the role of prostanoids, the downstream signaling lipids whose production is inhibited by NSAIDs, in promoting inflammation relevant to early-stage DR in two human retinal cell types: Müller glia and retinal microvascular endothelial cells. When cultured in multiple conditions modeling distinct aspects of systemic diabetes, Müller glia significantly increased production of prostaglandin E2 (PGE2), whereas retinal endothelial cells significantly increased production of prostaglandin F2α (PGF2α). Müller glia stimulated with PGE2 or PGF2α increased proinflammatory cytokine levels dose-dependently. These effects were blocked by selective antagonists to the EP2 receptor of PGE2 or the FP receptor of PGF2α, respectively. In contrast, only PGF2α stimulated adhesion molecule expression in retinal endothelial cells and leukocyte adhesion to cultured endothelial monolayers, effects that were fully prevented by FP receptor antagonist treatment. Together these results identify PGE2-EP2 and PGF2α-FP signaling as novel, selective targets for future studies and therapeutic development to mitigate or prevent retinal inflammation characteristic of early-stage DR.

Increased Adhesiveness of Blood Cells Induced by Mercury Chloride: Protective Effect of Hydroxytyrosol.

Mercury (Hg) is a highly toxic environmental contaminant that can harm human health, ultimately leading to endothelial dysfunction. Hg toxicity is partially mediated by the exposure of the cell membrane's surface of erythrocytes (RBCs) to phosphatidylserine (PS). In the context of these challenges, hydroxytyrosol, a phenolic compound of olive oil, has the ability to mitigate the toxic effects of Hg. This study aims to analyze the effect of Hg on the adhesion of RBCs and polymorphonuclear cells (PMNs) to the vascular endothelium and the potential protective effect of hydroxytyrosol, as these interactions are crucial in the development of cardiovascular diseases (CVDs). RBCs, PMNs, and human vein endothelial cells (HUVECs) were treated with increasing concentrations of HgCl2 and, in some cases, with hydroxytyrosol, and their adhesion to HUVECs and the expression of adhesion molecules were subsequently analyzed. Our results demonstrate that HgCl2 significantly increases the adhesion of both RBCs (2.72 ± 0.48 S.E.M., p-value < 0.02) and PMNs (11.19 ± 1.96 S.E.M., p-value < 0.05) to HUVECs and that their adhesiveness is significantly reduced following treatment with hydroxytyrosol (RBCs, 1.2 ± 1.18 S.E.M., p-value < 0.02 and PMNs, 4.04 ± 1.35 S.E.M., p-value < 0.06). Interestingly, HgCl2 does not alter the expression of adhesion molecules on either HUVECs or RBCs, suggesting that reduced exposure to PS is a key factor in hydroxytyrosol protection against HgCl2-induced RBC adhesion to the endothelium. On the other hand, HgCl2 induces increased expression of several PMN adhesion molecules (CD11b 215.4 ± 30.83 S.E.M. p-value < 0.01), while hydroxytyrosol inhibits their expression (e.g., CD11b 149 ± 14.35 S.E.M., p-value < 0.03), which would seem to be the mechanism by which hydroxytyrosol restricts PMN-endothelium interactions. These results provide new insights into the molecular mechanisms through which hydroxytyrosol mitigates the harmful effects of Hg on cardiovascular health, highlighting its potential as a therapeutic agent that can reduce the cardiovascular risk related to heavy metal exposure.

Reversal of Endothelial Cell Anergy by T Cell-Engaging Bispecific Antibodies.

Objectives: Reduced expression of adhesion molecules in tumor vasculature can limit infiltration of effector T cells. To improve T cell adhesion to tumor endothelial cell (EC) antigens and enhance transendothelial migration, we developed bispecific, T-cell engaging antibodies (bsAb) that activate T cells after cross-linking with EC cell surface antigens. Methods: Recombinant T-cell stimulatory anti-VEGFR2-anti-CD3 and costimulatory anti-TIE2-anti-CD28 or anti-PD-L1-anti-CD28 bsAb were engineered and expressed. Primary lines of human umbilical vein endothelial cells (HUVEC) that constitutively express VEGFR2 and TIE2 growth factor receptors and PD-L1, but very low levels of adhesion molecules, served as models for anergic tumor EC. Results: In cocultures with HUVEC, anti-VEGFR2-anti-CD3 bsAb increased T cell binding and elicited rapid T cell activation. The release of proinflammatory cytokines TNF-α, IFN-γ, and IL-6 was greatly augmented by the addition of anti-TIE2-anti-CD28 or anti-PD-L1-anti-CD28 costimulatory bsAb. Concomitantly, T cell-released cytokines upregulated E-selectin, ICAM1, and VCAM1 adhesion molecules on HUVEC. HUVEC cultured in breast cancer cell-conditioned medium to mimic the influence of tumor-secreted factors were similarly activated by T cell-engaging bsAb. Migration of T cells in transwell assays was significantly increased by anti-VEGFR2-anti-CD3 bsAb. The combination with costimulatory anti-TIE2-anti-CD28 bsAb augmented activation and proliferation of migrated T cells and their cytotoxic capacity against spheroids of the MCF-7 breast cancer cell line seeded in the lower transwell chamber. Conclusions: T cells activated by anti-VEGFR2-anti-CD3 and costimulatory EC-targeting bsAb can reverse the energy of quiescent EC in vitro, resulting in improved T cell migration through an EC layer.

Dengue infection changes the expressions of CD154 and CD148 in human platelets.

Platelets are essential for hemostasis and vascular integrity. Platelets recognize dengue virus through the DC-SIGN receptor. Upon pathogen recognition, platelets rapidly modulate the expression of adhesion molecules to trigger immune cell interactions and regulate the immune response. In this study, we aimed to examine the expression levels of three molecules, CD151, CD154, and CD148 on platelets in dengue patients. A significantly increased expression of CD154 and reduced expression of CD148 was observed in dengue patients compared to healthy subjects (p<0.0001). Moreover, a strong positive correlation between CD148 and CD41/CD61 (p<0.0001) was noted in dengue patients. In summary, we demonstrated the altered expressions of CD154 and CD148 on platelets in dengue patients that may play a crucial role in dengue pathogenesis.

Intranasal delivery of mesenchymal stem cell-derived exosomes ameliorates experimental autoimmune encephalomyelitis.

Exosomes derived from bone marrow mesenchymal stem cells (BMSCs-Exos) have shown therapeutic potential in experimental autoimmune encephalomyelitis (EAE). As a non-invasive method of drug administration, intranasal delivery is anticipated to emerge as a novel option for the treatment of central nervous system (CNS) disorders. Therefore, this study aims to treat EAE by nasal exosomes and explore its specific mechanism, especially its impact on the blood-brain barrier (BBB). BMSCs-Exos were isolated and characterized. An EAE model was then established, and these exosomes were administered intranasally to the mice. Changes in body weight and clinical scores were monitored following treatment to assess the efficacy. Additionally, inflammatory infiltrates and demyelination in the CNS were evaluated, alongside the quantification of expression levels of BBB-related adhesion molecules and tight junction (TJ) proteins. Intranasal delivery of BMSCs-Exos ameliorates the severity of EAE disease, reducing inflammatory infiltration in the CNS and demyelination in the spinal cord. This treatment did not influence the differentiation of T cells in the spleen. Furthermore, the nasal delivery of BMSCs-Exos enhances the integrity of TJs in the cerebral cortex and spinal cord, as well as inhibiting the expression of adhesion molecules. These exosomes promote the expression of TJ-related markers in bEnd3 cells, including ZO-1, Occludin, and Claudin 5. At the same time, they suppress the expression of adhesion molecule-related markers, such as ICAM1 and VCAM1. Our study suggests that intranasal administration of BMSCs-Exos significantly reduces inflammatory infiltration and demyelination in the CNS of EAE mice. Furthermore, this treatment does not influence the differentiation of T cells in the spleen. Additionally, nasal reinfusion of BMSCs-Exos can improve the integrity of the BBB in EAE mice.

An immunocompetent human kidney on-a-chip model to study renal inflammation and immune-mediated injury.

Kidney damage and dysfunction is an emerging health issue worldwide resulting in high morbidity and mortality rates. Numerous renal diseases are recognized to be driven by the immune system. Despite this recognition, the development of targeted therapies has been challenging as knowledge of the underlying mechanism and complex interactions remains insufficient. Recent advancements in the field offer promising avenues for exploring the interplay between renal cells and immune cells and their role in the development of renal inflammation and diseases. This study describes the establishment of a human immunocompetent 3D in vitro co-culture model of the proximal tubule in a high-throughput microfluidic platform that can be used to study renal functionality and inflammatory processes. &#xD;The model incorporated RPTEC in the top compartment and HUVECs in the bottom compartment cultured under flow and in direct contact with a collagen-I ECM gel resulting in the formation of polarized tubular structures. As an immune component, human primary monocytes of different donors were added to the lumen of the endothelium. Renal inflammation was successfully induced using complement activated serum (CAS) as evident by epithelial morphological changes, increased expression of adhesion molecules, release of pro-inflammatory cytokines, and reduced epithelial viability. Realtime migratory behavior of monocytes showed increased extravasation and migration towards the ECM and Renal compartment upon exposure to CAS with donor-to-donor differences observed. Finally, immune modulatory compounds showed efficacious inhibition of monocyte migration under inflammatory conditions in the microfluidic co-culture model. &#xD;A successful co-culture model was established and can be applied to study renal functionality in health and disease but also for drug screening due to the compatibility of the platform with automation and relatively high throughput. Overall, the described proximal tubule model has high potential to fill the gap that currently exists to study renal inflammation preclinically.&#xD.

Carbonic anhydrase inhibitors prevent presymptomatic capillary flow disturbances in a model of cerebral amyloidosis.

Disturbances in microvascular flow dynamics are hypothesized to precede the symptomatic phase of Alzheimer's disease (AD). However, evidence in presymptomatic AD remains elusive, underscoring the need for therapies targeting these early vascular changes. We employed a multimodal approach, combining in vivo optical imaging, molecular techniques, and ex vivo MRI, to investigate early capillary dysfunction in Tg-SwDI mice without memory impairment. We also assessed the efficacy of carbonic anhydrase inhibitors (CAIs) in preventing capillary flow disturbances. Our study revealed capillary flow disturbances associated with alterations in capillary morphology, adhesion molecule expression, and Amyloid-β (Aβ) load in 9-10-month-old Tg-SwDI mice without memory impairment. CAI treatment ameliorated these capillary flow disturbances, enhanced oxygen availability, and reduced Aβ load. These findings underscore the importance of capillary flow disturbances as early biomarkers in presymptomatic AD and highlight the potential of CAIs for preserving vascular integrity in the early stages of AD.

The Role of Endothelial L-PGDS in the Pro-Angiogenic and Anti-Inflammatory Effects of Low-Dose Alcohol Consumption.

Light alcohol consumption (LAC) may reduce the incidence and improve the prognosis of ischemic stroke. Recently, we found that LAC promotes cerebral angiogenesis and inhibits early inflammation following ischemic stroke. In addition, LAC upregulates lipocalin-type prostaglandin D2 synthase (L-PGDS) in the brain. Thus, we determined the role of endothelial L-PGDS in the protective effect of LAC. In in vitro studies, chronic exposure to low-concentration ethanol upregulated L-PGDS and significantly increased the proliferation in cultured C57BL/6J mouse brain microvascular endothelial cells (MBMVECs). AT-56, a selective L-PGDS inhibitor, abolished low-concentration ethanol exposure-induced proliferation. In in vivo studies, 8-week gavage feeding with 0.7 g/kg/day ethanol, defined as LAC, promoted cerebral angiogenesis under physiological conditions and following ischemic stroke in male C57BL/6J mice. In addition, LAC inhibited the post-ischemic expression of adhesion molecules, neutrophil infiltration, and microglial activation. AT-56 and endothelial cell (EC)-specific L-PGDS conditional knockout did not significantly alter cerebral angiogenesis and post-ischemic inflammation in the control mice but eliminated the pro-angiogenic and anti-inflammatory effects of LAC. Furthermore, EC-specific L-PGDS conditional knockout alleviated the neuroprotective effect of LAC against cerebral ischemia/reperfusion injury. These findings suggest that endothelial L-PGDS may be crucial in the pro-angiogenic and anti-inflammatory effects of LAC against ischemic stroke.