Anti-Inflammatory Activity of Ferula assafoetida Oleo-Gum-Resin (Asafoetida) against TNF-α-Stimulated Human Umbilical Vein Endothelial Cells (HUVECs).

Inflammation is the body's biological reaction to endogenous and exogenous stimuli. Recent studies have demonstrated several anti-inflammatory properties of Ferula species. In this paper, we decided to study the anti-inflammatory effect of ethanolic extract of Ferula assafoetida oleo-gum-resin (asafoetida) against TNF-α-stimulated human umbilical vein endothelial cells (HUVECs). HUVECs were cultured in a flat-bottom plate and then treated with ethanolic extract of asafoetida (EEA, 0-500 µg/ml) and TNF-α (0-100 ng/ml) for 24 h. We used the MTT test to assess cell survival. In addition, the LC-MS analysis was performed to determine the active substances. HUVECs were pretreated with EEA and then induced by TNF-α. Intracellular reactive oxygen species (ROS) and adhesion of peripheral blood mononuclear cells (PBMCs) to HUVECs were evaluated with DCFH-DA and CFSE fluorescent probes, respectively. Gene expression of intercellular cell adhesion molecule-1 (ICAM-1), vascular cell adhesion molecule 1 (VCAM-1), and E-selectin and surface expression of ICAM-1 protein were measured using real-time PCR and flow cytometry methods, respectively. While TNF-α significantly increased intracellular ROS formation and PBMC adhesion to TNF-α-induced HUVECs, the pretreatment of HUVECs with EEA (125 and 250 µg/ml) significantly reduced the parameters. In addition, EEA pretreatment decreased TNF-α-induced mRNA expression of VCAM-1 and surface protein expression of ICAM-1 in the target cells. Taken together, the results indicated that EEA prevented ROS generation, triggered by TNF-α, and inhibited the expression of VCAM-1 and ICAM-1, leading to reduced PBMC adhesion. These findings suggest that EEA can probably have anti-inflammatory properties.

Mycobacterium bovis Bacillus Calmette-Guérin-Infected Dendritic Cells Induce TNF-α-Dependent Cell Cluster Formation That Promotes Bacterial Dissemination through an In Vitro Model of the Blood-Brain Barrier.

CNS tuberculosis (CNSTB) is the most severe manifestation of extrapulmonary tuberculosis infection, but the mechanism of how mycobacteria cross the blood-brain barrier (BBB) is not well understood. In this study, we report a novel murine in vitro BBB model combining primary brain endothelial cells, Mycobacterium bovis bacillus Calmette-Guérin-infected dendritic cells (DCs), PBMCs, and bacterial Ag-specific CD4+ T cells. We show that mycobacterial infection limits DC mobility and also induces cellular cluster formation that has a similar composition to pulmonary mycobacterial granulomas. Within the clusters, infection from DCs disseminates to the recruited monocytes, promoting bacterial expansion. Mycobacterium-induced in vitro granulomas have been described previously, but this report shows that they can form on brain endothelial cell monolayers. Cellular cluster formation leads to cluster-associated damage of the endothelial cell monolayer defined by mitochondrial stress, disorganization of the tight junction proteins ZO-1 and claudin-5, upregulation of the adhesion molecules VCAM-1 and ICAM-1, and increased transmigration of bacteria-infected cells across the BBB. TNF-α inhibition reduces cluster formation on brain endothelial cells and mitigates cluster-associated damage. These data describe a model of bacterial dissemination across the BBB shedding light on a mechanism that might contribute to CNS tuberculosis infection and facilitate treatments.

Endothelial STING controls T cell transmigration in an IFNI-dependent manner.

The stimulator of IFN genes (STING) protein senses cyclic dinucleotides released in response to double-stranded DNA and functions as an adaptor molecule for type I IFN (IFNI) signaling by activating IFNI-stimulated genes (ISG). We found impaired T cell infiltration into the peritoneum in response to TNF-α in global and EC-specific STING-/- mice and discovered that T cell transendothelial migration (TEM) across mouse and human endothelial cells (EC) deficient in STING was strikingly reduced compared with control EC, whereas T cell adhesion was not impaired. STING-/- T cells showed no defect in TEM or adhesion to EC, or immobilized endothelial cell-expressed molecules ICAM1 and VCAM1, compared with WT T cells. Mechanistically, CXCL10, an ISG and a chemoattractant for T cells, was dramatically reduced in TNF-α-stimulated STING-/- EC, and genetic loss or pharmacologic antagonisms of IFNI receptor (IFNAR) pathway reduced T cell TEM. Our data demonstrate a central role for EC-STING during T cell TEM that is dependent on the ISG CXCL10 and on IFNI/IFNAR signaling.

Pericytes regulate vascular immune homeostasis in the CNS.

Pericytes regulate the development of organ-specific characteristics of the brain vasculature such as the blood-brain barrier (BBB) and astrocytic end-feet. Whether pericytes are involved in the control of leukocyte trafficking in the adult central nervous system (CNS), a process tightly regulated by CNS vasculature, remains elusive. Using adult pericyte-deficient mice (Pdgfbret/ret ), we show that pericytes limit leukocyte infiltration into the CNS during homeostasis and autoimmune neuroinflammation. The permissiveness of the vasculature toward leukocyte trafficking in Pdgfbret/ret mice inversely correlates with vessel pericyte coverage. Upon induction of experimental autoimmune encephalomyelitis (EAE), pericyte-deficient mice die of severe atypical EAE, which can be reversed with fingolimod, indicating that the mortality is due to the massive influx of immune cells into the brain. Additionally, administration of anti-VCAM-1 and anti-ICAM-1 antibodies reduces leukocyte infiltration and diminishes the severity of atypical EAE symptoms of Pdgfbret/ret mice, indicating that the proinflammatory endothelium due to absence of pericytes facilitates exaggerated neuroinflammation. Furthermore, we show that the presence of myelin peptide-specific peripheral T cells in Pdgfbret/ret ;2D2tg mice leads to the development of spontaneous neurological symptoms paralleled by the massive influx of leukocytes into the brain. These findings indicate that intrinsic changes within brain vasculature can promote the development of a neuroinflammatory disorder.

Dingxin recipe alleviates atherosclerosis injury in ApoE-knockout mice via downregulation of visfatin expression and inhibition of the visfatin-induced inflammatory response.

OBJECTIVE: To further elucidate the mechanism underlying the anti-atherosclerotic effect of Dingxin recipe (DXR). METHODS: Fifty 6-week-old male ApoE-/- mice were randomly divided into the following groups: model, simvastatin (5 mg·kg－1·d－1), DXR low-dose (9.30 g·kg－1·d－1), DXR middle-dose (18.59 g·kg－1·d－1) and DXR high-dose (37.18 g·kg－1·d－1) (n = 10). Ten male C57BL/6J mice were used as the control group. All ApoE-/- mice were fed a high-fat diet (HFD) and the control mice received a common diet. After HFD for 12 weeks, the mice were treated with DXR or simvastatin for another 12 weeks. The expression of inflammatory cytokines and visfatin was determined in serum and atherosclerotic lesions by enzyme-linked immunosorbent assay. Visfatin expression was also assessed in aortic atherosclerotic plaques. Cultured vessel endothelial cells (VECs) were pretreated with DXR sera prior to visfatin. The effects of DXR were analyzed to elucidate its protective mechanism against visfatin-induced inflammation in VECs. RESULTS: DXR regulated blood lipids and reduced tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), intercellular adhesion molecules-1 (ICAM-1), vascular cell adhesion molecule-1 (VCAM-1) and visfatin expression in ApoE-/- mice, particularly at the higher doses. The areas of atherosclerotic lesions in the DXR groups were significantly smaller than those in the model group. DXR alleviated visfatin-induced VEC injury via downregulation of TNF-α, IL-6, ICAM-1 and VCAM-1 through mitogen-activated protein kinase pathways. CONCLUSION: DXR alleviated atherosclerosis injury via downregulation of visfatin expression and inhibition of the visfatin-induced inflammatory response in VECs.

Inflammatory and endothelial dysfunction indices among Egyptian females with obesity classes I-III.

BACKGROUND: Obesity is an alarming threat to health in Egypt. More than one in three Egyptians is obese, the highest rate in the world. We aimed to delineate the variability of inflammation and endothelial dysfunction markers among Egyptian females with different obesity classes. METHODS: Out of 130 females, 70 were categorized into three obesity groups: Class I, body mass index (BMI) 30-34.9 kg/m2; Class II, BMI 35-39.9 kg/m2 and Class III BMI ≥ 40 kg/m2, besides 60 control subjects. Anthropometric measurements were recorded and serum levels of tumor necrosis factor-α (TNF-α), C-reactive protein (CRP), interleukin (IL) 6 (IL-6), IL-12, soluble intercellular adhesion molecule 1 (sICAM-1) and soluble vascular adhesion molecule 1 (sVCAM-1) were assessed among participants. RESULTS: In all three classes of obesity, significant increase (P <0.05) in BMI, waist-hip ratio, fat mass and body fat mass % were noted. CRP and sVCAM-1 levels were increased among the three obesity groups. TNF-α levels were increased in class II and III obesity groups. IL-6 and IL-12 levels were elevated in class I and class III groups. While, ICAM-1 levels were increased in class III obesity group. CONCLUSION: Based on individuals' BMI, serum levels of TNF-α, CRP, IL-6, IL-12, sVCAM-1 and sICAM-1 are differentially altered with the progression of obesity. We strongly support the hypothesis that, as the obesity rate is still mounting, a subclinical inflammatory reaction has a role in pathogenesis of obesity and emphasize the elevation of endothelial dysfunction in individuals with obesity.

Dietary γ-Glutamyl Valine Ameliorates TNF-α-Induced Vascular Inflammation via Endothelial Calcium-Sensing Receptors.

γ-Glutamyl valine (γ-EV), commonly found in edible beans, was shown to reduce gastrointestinal inflammation via activation of calcium-sensing receptors (CaSRs). The present study aimed to evaluate the efficacy of γ-EV in modulating the tumor necrosis factor-α-induced inflammatory responses in endothelial cells (ECs) via CaSR-mediated pathways. Human aortic ECs (HAoECs) were pretreated (2 h) with γ-EV (0.01, 0.1, and 1 mM). 1 mM pretreatment of γ-EV significantly reduced the upregulation of inflammatory adhesion molecules, VCAM-1 and E-selectin, by 44.56 and 57.41%, respectively. The production of cytokines IL-8 and IL-6 was significantly reduced by 40 and 51%, respectively, with 1 mM pretreatment of γ-EV. Similarly, there was a significant reduction in chemokine MCP-1 from a positive control of 9.70 ± 0.52 to 6.6 ± 0.43 ng/mL, after γ-EV treatment. The anti-inflammatory effect of γ-EV was attenuated by the treatment of the CaSR-specific inhibitor, NPS-2143, suggesting the involvement of CaSR-mediated pathways. Further studies identified the critical role of key modulators, such as ß-arrestin2 and cyclic adenosine monophosphate response element-binding protein, in mediating the CaSR-dependent anti-inflammatory effect of γ-EV. Finally, the transport efficiency of γ-EV was evaluated through a monolayer of intestinal epithelial cells (Caco-2), and the apparent permeability (Papp) of the peptide was found to be 1.56 × 10-6 cm/s.

Human Fallopian Tube Epithelial Cell Culture Model To Study Host Responses to Chlamydia trachomatis Infection.

Chlamydia trachomatis infection of the human fallopian tubes can lead to damaging inflammation and scarring, ultimately resulting in infertility. To study the human cellular responses to chlamydial infection, researchers have frequently used transformed cell lines that can have limited translational relevance. We developed a primary human fallopian tube epithelial cell model based on a method previously established for culture of primary human bronchial epithelial cells. After protease digestion and physical dissociation of excised fallopian tubes, epithelial cell precursors were expanded in growth factor-containing medium. Expanded cells were cryopreserved to generate a biobank of cells from multiple donors and cultured at an air-liquid interface. Culture conditions stimulated cellular differentiation into polarized mucin-secreting and multiciliated cells, recapitulating the architecture of human fallopian tube epithelium. The polarized and differentiated cells were infected with a clinical isolate of C. trachomatis, and inclusions containing chlamydial developmental forms were visualized by fluorescence and electron microscopy. Apical secretions from infected cells contained increased amounts of proteins associated with chlamydial growth and replication, including transferrin receptor protein 1, the amino acid transporters SLC3A2 and SLC1A5, and the T-cell chemoattractants CXCL10, CXCL11, and RANTES. Flow cytometry revealed that chlamydial infection induced cell surface expression of T-cell homing and activation proteins, including ICAM-1, VCAM-1, HLA class I and II, and interferon gamma receptor. This human fallopian tube epithelial cell culture model is an important tool with translational potential for studying cellular responses to Chlamydia and other sexually transmitted pathogens.

Selective targeting of nanomedicine to inflamed cerebral vasculature to enhance the blood-brain barrier.

Drug targeting to inflammatory brain pathologies such as stroke and traumatic brain injury remains an elusive goal. Using a mouse model of acute brain inflammation induced by local tumor necrosis factor alpha (TNFα), we found that uptake of intravenously injected antibody to vascular cell adhesion molecule 1 (anti-VCAM) in the inflamed brain is >10-fold greater than antibodies to transferrin receptor-1 and intercellular adhesion molecule 1 (TfR-1 and ICAM-1). Furthermore, uptake of anti-VCAM/liposomes exceeded that of anti-TfR and anti-ICAM counterparts by ∼27- and ∼8-fold, respectively, achieving brain/blood ratio >300-fold higher than that of immunoglobulin G/liposomes. Single-photon emission computed tomography imaging affirmed specific anti-VCAM/liposome targeting to inflamed brain in mice. Intravital microscopy via cranial window and flow cytometry showed that in the inflamed brain anti-VCAM/liposomes bind to endothelium, not to leukocytes. Anti-VCAM/LNP selectively accumulated in the inflamed brain, providing de novo expression of proteins encoded by cargo messenger RNA (mRNA). Anti-VCAM/LNP-mRNA mediated expression of thrombomodulin (a natural endothelial inhibitor of thrombosis, inflammation, and vascular leakage) and alleviated TNFα-induced brain edema. Thus VCAM-directed nanocarriers provide a platform for cerebrovascular targeting to inflamed brain, with the goal of normalizing the integrity of the blood-brain barrier, thus benefiting numerous brain pathologies.

Epigenetic Heterogeneity and Mitotic Heritability Prime Endothelial Cell Gene Induction.

Homogeneous populations of mature differentiated primary cell types can display variable responsiveness to extracellular stimuli, although little is known about the underlying mechanisms that govern such heterogeneity at the level of gene expression. In this article, we show that morphologically homogenous human endothelial cells exhibit heterogeneous expression of VCAM1 after TNF-α stimulation. Variability in VCAM1 expression was not due to stochasticity of intracellular signal transduction but rather to preexisting established heterogeneous states of promoter DNA methylation that were generationally conserved through mitosis. Variability in DNA methylation of the VCAM1 promoter resulted in graded RelA/p65 and RNA polymerase II binding that gave rise to a distribution of VCAM1 transcription in the population after TNF-α stimulation. Microarray analysis and single-cell RNA sequencing revealed that a number of cytokine-inducible genes shared this heterogeneous response pattern. These results show that heritable epigenetic heterogeneity is fundamental in inflammatory signaling and highlight VCAM1 as a metastable epiallele.

VCAM-1 targeted alpha-particle therapy for early brain metastases.

BACKGROUND: Brain metastases (BM) develop frequently in patients with breast cancer. Despite the use of external beam radiotherapy (EBRT), the average overall survival is short (6 months from diagnosis). The therapeutic challenge is to deliver molecularly targeted therapy at an early stage when relatively few metastatic tumor cells have invaded the brain. Vascular cell adhesion molecule 1 (VCAM-1), overexpressed by nearby endothelial cells during the early stages of BM development, is a promising target. The aim of this study was to investigate the therapeutic value of targeted alpha-particle radiotherapy, combining lead-212 (212Pb) with an anti-VCAM-1 antibody (212Pb-αVCAM-1). METHODS: Human breast carcinoma cells that metastasize to the brain, MDA-231-Br-GFP, were injected into the left cardiac ventricle of nude mice. Twenty-one days after injection, 212Pb-αVCAM-1 uptake in early BM was determined in a biodistribution study and systemic/brain toxicity was evaluated. Therapeutic efficacy was assessed using MR imaging and histology. Overall survival after 212Pb-αVCAM-1 treatment was compared with that observed after standard EBRT. RESULTS: 212Pb-αVCAM-1 was taken up into early BM with a tumor/healthy brain dose deposition ratio of 6 (5.52e108 and 0.92e108) disintegrations per gram of BM and healthy tissue, respectively. MRI analyses showed a statistically significant reduction in metastatic burden after 212Pb-αVCAM-1 treatment compared with EBRT (P < 0.001), translating to an increase in overall survival of 29% at 40 days post prescription (P < 0.01). No major toxicity was observed. CONCLUSIONS: The present investigation demonstrates that 212Pb-αVCAM-1 specifically accumulates at sites of early BM causing tumor growth inhibition.

Graft-versus-host disease of the CNS is mediated by TNF upregulation in microglia.

Acute graft-versus-host disease (GVHD) can affect the central nervous system (CNS). The role of microglia in CNS-GVHD remains undefined. In agreement with microglia activation, we found that profound morphological changes and MHC-II and CD80 upregulation occurred upon GVHD induction. RNA sequencing-based analysis of purified microglia obtained from mice with CNS-GVHD revealed TNF upregulation. Selective TNF gene deletion in microglia of Cx3cr1creER Tnffl/- mice reduced MHC-II expression and decreased CNS T cell infiltrates and VCAM-1+ endothelial cells. GVHD increased microglia TGF-ß-activated kinase-1 (TAK1) activation and NF-κB/p38 MAPK signaling. Selective Tak1 deletion in microglia using Cx3cr1creER Tak1fl/fl mice resulted in reduced TNF production and microglial MHC-II and improved neurocognitive activity. Pharmacological TAK1 inhibition reduced TNF production and MHC-II expression by microglia, Th1 and Th17 T cell infiltrates, and VCAM-1+ endothelial cells and improved neurocognitive activity, without blocking graft-versus-leukemia effects. Consistent with these findings in mice, we observed increased activation and TNF production of microglia in the CNS of GVHD patients. In summary, we prove a role for microglia in CNS-GVHD, identify the TAK1/TNF/MHC-II axis as a mediator of CNS-GVHD, and provide a TAK1 inhibitor-based approach against GVHD-induced neurotoxicity.

Inflammation inhibition and gut microbiota regulation by TSG to combat atherosclerosis in ApoE-/- mice.

ETHNOPHARMACOLOGICAL RELEVANCE: 2,3,5,4'-Tetrahydroxy-stilbene-2-O-ß-D-glucoside (TSG) is the main active component of Polygoni Multiflori Radix, a root of the homonymous plant widely used in traditional Chinese medicine. TSG has protective effects on the liver, reduces cholesterol and possesses anti-oxidant, anti-tumor, and anti-atherosclerotic properties. However, the pharmacological effects and mechanisms of action of Polygonum multiflorum on atherosclerosis (AS) have not been studied yet. PURPOSE: The aim of this research was to study the effects of Polygoni Multiflori Radix Praeparata (PMRP) and its major active chemical constituent TSG on AS in ApoE-deficient (ApoE-/-) mice fed with high fat diets to provide a scientific basis in the use of PMRP and TSG against cardiovascular diseases. METHODS: High fat diet induced AS in ApoE-/- mice were treated with PMRP, TSG (low and high doses), and simvastatin (SIM) for 8 weeks. At the end of the treatment, mouse serum lipid levels, triglycerides (TG), and total cholesterol (TC) were measured by an oxidase method (other indicators were determined by ELISA), while the content in oxidized low density lipoprotein (ox-LDL) and the expression of inflammatory factors such as interleukin-6 (IL-6), tumor necrosis factor-α (TNF-α), vascular cell adhesion molecule-1 (VCAM-1), and monocyte chemotactic protein-1 (MCP-1) in the serum and aortic samples were measured by ELISA. Atherosclerotic plaque morphology was evaluated by oil red O in thoracic aorta. In addition, 16S rDNA-V4 hypervariable region genome sequence of all microbes in the fecal sample from each group was analyzed to evaluate potential structure changes in the gut microbiota after treatment with PMRP and TSG. RESULTS: TSG markedly inhibited AS plaque formation in ApoE-/- mice. Furthermore, PMRP and TSG improved lipid accumulation by reducing TG and ox-LDL levels. TSG inhibited inflammation by the down-regulation of IL-6, TNF-α, VCAM-1 and MCP-1 expression in serum, and PMRP inhibited inflammation by reducing VCAM-1, ICAM-1 and CCRA expression in aortic tissue. In addition, TSG reduced or prevented AS by the regulation of the composition of the overall gut microbiota, such as Firmicutes, Bacteroidetes, Tenericutes, Proteobacteria phyla, Akkermensia genera and Helicobacter pylori. CONCLUSION: PMRP and TSG improved lipid accumulation and inflammation, and regulated the intestinal microbial imbalance in ApoE-/- mice. TSG exerted a preventive effect in the development and progression of AS.

Radionuclide spatial distribution and dose deposition for in vitro assessments of 212 Pb-αVCAM-1 targeted alpha therapy.

PURPOSE: Targeted alpha therapy (TAT) takes advantage of the short-range and high-linear energy transfer of α-particles and is increasingly used, especially for the treatment of metastatic lesions. Nevertheless, dosimetry of α-emitters is challenging for the very same reasons, even for in vitro experiments. Assumptions, such as the uniformity of the distribution of radionuclides in the culture medium, are commonly made, which could have a profound impact on dose calculations. In this study we measured the spatial distribution of α-emitting 212 Pb coupled to an anti-VCAM-1 antibody (212 Pb-αVCAM-1) and its evolution over time in the context of in vitro irradiations. METHODS: Two experimental setups were implemented without cells to measure α-particle count rates and energy spectra in culture medium containing 15 kBq of 212 Pb-α-VCAM-1. Silicon detectors were placed above and below cell culture dishes for 20 h. One of the dishes had a 2.5-µm-thick mylar-base allowing easy detection of the α-particles. Monte Carlo simulations were performed to analyze experimental spectra. Experimental setups were modeled and α-energy spectra were simulated in the silicon detectors for different decay positions in the culture medium. Simulated spectra were then used to deconvolute experimental spectra to determine the spatial distribution of 212 Pb-αVCAM-1 in the medium. This distribution was finally used to calculate the dose deposition in cell culture experiments. RESULTS: Experimental count rates and energy spectra showed differences in measurements taken at the top and the bottom of dishes and temporal variations that did not follow 212 Pb decay. The radionuclide spatial distribution was shown to be composed of a uniform distribution and concentration gradients at the top and the bottom, which were subjected to temporal variations that may be explained by gravity and electrostatic attraction. The absorbed dose in cells calculated from this distribution was compared with the dose expected for a uniform and static distribution and found to be 1.75 times higher, which is highly significant to interpret biological observations. CONCLUSIONS: This study demonstrated that accurate dosimetry of α-emitters requires the experimental determination of radionuclide spatial and temporal distribution and highlighted that in vitro assessment of dose for TAT cannot only rely on a uniform distribution of activity in the culture medium. The reliability and reproducibility of future experiments should benefit from specifically developed dosimetry tools and methods.

Surfactant protein-D modulation of pulmonary macrophage phenotype is controlled by S-nitrosylation.

Surfactant protein-D (SP-D) is a regulator of pulmonary innate immunity whose oligomeric state can be altered through S-nitrosylation to regulate its signaling function in macrophages. Here, we examined how nitrosylation of SP-D alters the phenotypic response of macrophages to stimuli both in vivo and in vitro. Bronchoalveolar lavage (BAL) from C57BL6/J and SP-D-overexpressing (SP-D OE) mice was incubated with RAW264.7 cells ± LPS. LPS induces the expression of the inflammatory genes Il1b and Nos2, which is reduced 10-fold by SP-D OE-BAL. S-nitrosylation of the SP-D OE-BAL (SNO-SP-D OE-BAL) abrogated this inhibition. SNO-SP-D OE-BAL alone induced Il1b and Nos2 expression. PCR array analysis of macrophages incubated with SP-D OE-BAL (±LPS) shows increased expression of repair genes, Ccl20, Cxcl1, and Vcam1, that was accentuated by LPS. LPS increases inflammatory gene expression, Il1a, Nos2, Tnf, and Ptgs2, which was accentuated by SNO-SP-D OE-BAL but inhibited by SP-D OE-BAL. The transcription factor NF-κB was identified as a target for SNO-SP-D by IPA, which was confirmed by Trans-AM ELISA in vitro. In vivo, SP-D overexpression increases the burden of infection in a Pneumocystis model while increasing cellular recruitment. Expression of iNOS and the production of NO metabolites were significantly reduced in SP-D OE mice relative to C57BL6/J. Inflammatory gene expression was increased in infected C57BL6/J mice but decreased in SP-D OE. SP-D oligomeric structure was disrupted in C57BL6/J infected mice but unaltered within SP-D OE. Thus SP-D modulates macrophage phenotype and the balance of multimeric to trimeric SP-D is critical to this regulation.

Embryonic FAP+ lymphoid tissue organizer cells generate the reticular network of adult lymph nodes.

The induction of adaptive immunity is dependent on the structural organization of LNs, which is in turn governed by the stromal cells that underpin LN architecture. Using a novel fate-mapping mouse model, we trace the developmental origin of mesenchymal LN stromal cells (mLNSCs) to a previously undescribed embryonic fibroblast activation protein-α (FAP)+ progenitor. FAP+ cells of the LN anlagen express lymphotoxin ß receptor (LTßR) and vascular cell adhesion molecule (VCAM), but not intercellular adhesion molecule (ICAM), suggesting they are early mesenchymal lymphoid tissue organizer (mLTo) cells. Clonal labeling shows that FAP+ progenitors locally differentiate into mLNSCs. This process is also coopted in nonlymphoid tissues in response to infection to facilitate the development of tertiary lymphoid structures, thereby mimicking the process of LN ontogeny in response to infection.

Anti-VCAM 1 Antibody-Coated Mesenchymal Stromal Cells Attenuate Experimental Colitis via Immunomodulation.

BACKGROUND The treatment of inflammatory bowel disease (IBD) is still not satisfactory and novel technologies are clinically needed. This study aimed to examine the effect of mesenchymal stromal cells (MSCs) coated with the anti-vascular cell adhesion molecule 1 (VCAM 1) antibody on experimental colitis. MATERIAL AND METHODS The antibody was coated onto the MSCs isolated from male BALB/C mice to generate anti-VCAM 1 antibody-coated MSC (V-MSC). The Transwell assay was used to detect migration rate. 2,4,6-trinitrobenzenesulfonic acid (TNBS) was used to generate experimental colitis. MSCs were injected intravenously into experimental models. Weight changes, disease activity index, and histological changes were evaluated. The SRY gene were used for cell tracking. Expression of Ki67 and claudin 1 was used to measure local repair using immunohistochemistry. T helper (Th)1, Th2, Th17, and T regulatory cells were counted. RESULTS V-MSCs were successfully generated through coating MSCs with VCAM1 antibody. Analysis showed that the V-MSCs had similar surface types and differentiation as uncoated MSCs. Transwell assays showed that V-MSCs had higher migration rate than MSCs. After injection of V-MSCs, the expression of the SRY gene was enhanced in diseased colon and all indices (including weight changes, DAI score, histological changes, and the expressions of Ki67 and claudin 1) recovered rapidly. The ratio of proinflammatory Th1 and Th17 cells decreased, but the ratio of anti-inflammatory Th2 and Treg cells increased after the treatment. CONCLUSIONS V-MSCs enhance homing and modulating immune balance in the experimental colitis, suggesting that they are potentially useful for treating inflammatory bowel disease or other immune diseases.

Bone marrow mesenchymal stem cells and condition media diminish inflammatory adhesion molecules of pulmonary endothelial cells in an ovalbumin-induced asthmatic rat model.

OBJECTIVES: Although excitements related to stem cell therapeutic outcomes have been highlighted enormously in asthma, the vast majority of works were conducted by researchers in animal models. Elucidating the mechanisms underlying the therapeutic effects of MSCs in asthmatic rats will provide a rational basis for assuring maximal safety of future clinical application of stem cells. In the current study, we sought to investigate the possible paracrine mechanism by which direct injection of MSCs and/or CM attenuate efficiently Th2-mediated inflammation in asthmatic lung tissues with the focus on ICAM-1 and VCAM-1 expression. METHODS: Male rats were divided into four experimental groups (n = 6); healthy rats received PBS intratracheally (group C), sensitized rats received PBS intratracheally (group S), sensitized rats received CM intratracheally (group S + CM), and sensitized rats received PBS intratracheally containing 2 × 106 rBMMSCs (group S + MSCs). Two weeks post-transplantation, the expression of interleukin (IL)-5, -12 and INF-γ, ICAM-1 and VCAM-1 were assessed along with pathological injuries and the homing of MSCs into the lung tissues. RESULTS: Our results showed CM, and notably rBMMSCs, returned the expression of IL-5, IL-12, INF-γ, ICAM-1, and VCAM-1 (p < 0.001 to p < 0.05) to the normal levels. Based on data, pathological injuries in pulmonary specimens of asthmatic rats were significantly attenuated (p < 0.001 to p < 0.05). Moreover, rBMMSCs had potential to successfully home to an asthmatic niche in cell-administrated rats. CONCLUSIONS: Our data noted the potency of CM and especially MSCs in ameliorating pathological changes via intra-tracheal route presumably by targeting ICAM-1 and VCAM-1 in lung tissues in rat asthma model.

VCAM-1-mediated neutrophil infiltration exacerbates ambient fine particle-induced lung injury.

BACKGROUND: Fine ambient particle matter (PM2.5) induces inflammatory lung injury; however, whether intratracheal administration of PM2.5 increases pulmonary polymorphonuclear leukocyte (PMN) infiltration, the mechanism of infiltration, and if these cells exacerbate PM2.5-induced lung injury are unknown. METHODS: Using 32,704 subjects, the association between blood PMNs and ambient PM2.5 levels on the previous day was retrospectively analyzed. Neutropenia was achieved by injecting mice with PMN-specific antibodies. Inhibition of PMN infiltration was achieved by pretreating PMNs with soluble vascular cell adhesion molecule-1 (sVCAM-1). The effects of PMNs on PM2.5-induced lung injury and endothelial dysfunction were observed. RESULT: Short-term PM2.5 (> 75 µg/m3 air) exposure increased the PMN/white blood cell ratio and the PMN count in human peripheral blood observed during routine examination. A significant number of PM2.5-treated PMNs was able to bind sVCAM-1. In mice, intratracheally-instilled PM2.5 deposited in the alveolar space and endothelial cells, which caused significant lung edema, morphological disorder, increased permeability of the endothelial-alveolar epithelial barrier, and PMN infiltration with increased VCAM-1 expression. Depletion of circulatory PMNs inhibited these adverse effects. Replenishment of untreated PMNs, but not those pretreated with soluble VCAM-1, restored lung injury. In vitro, PM2.5 increased VCAM-1 expression and endothelial and epithelial monolayer permeability, and promoted PMN adhesion to, chemotaxis toward, and migration across these monolayers. PMNs, but not those pretreated with soluble VCAM-1, exacerbated these effects. CONCLUSION: VCAM-1-mediated PMN infiltration was essential for a detrimental cycle of PM2.5-induced inflammation and lung injury. Results suggest that drugs that inhibit PMN function might prevent acute deterioration of chronic pulmonary and cardiovascular diseases triggered by PM2.5.

Kyasanur Forest disease virus infection activates human vascular endothelial cells and monocyte-derived dendritic cells.

Kyasanur Forest disease virus (KFDV) is a highly pathogenic tick-borne flavivirus enzootic to India. In humans, KFDV causes a severe febrile disease. In some infected individuals, hemorrhagic manifestations, such as bleeding from the nose and gums and gastrointestinal bleeding with hematemesis and/or blood in the stool, have been reported. However, the mechanisms underlying these hemorrhagic complications remain unknown, and there is no information about the specific target cells for KFDV. We investigated the interaction of KFDV with vascular endothelial cells (ECs) and monocyte-derived dendritic cells (moDCs), which are key targets for several other hemorrhagic viruses. Here, we report that ECs are permissive to KFDV infection, which leads to their activation, as demonstrated by the upregulation of E-selectin, intercellular adhesion molecule 1, and vascular cell adhesion molecule 1 at the mRNA and protein levels. Increased expression of these adhesive molecules correlated with increased leukocyte adhesion. Infected ECs upregulated the expression of interleukin (IL)-6 but not IL-8. Additionally, moDCs were permissive to KFDV infection, leading to increased release of IL-6 and tumor necrosis factor-α. Supernatants from KFDV-infected moDCs caused EC activation, as measured by leukocyte adhesion. The results indicate that ECs and moDCs can be targets for KFDV and that both direct and indirect mechanisms can contribute to EC activation.