Endothelial cells at inflammatory sites as target for therapeutic intervention

Intercellular Adhesion Molecule 1 (ICAM-1): An Inflammatory Regulator with Potential Implications in Ferroptosis and Parkinson's Disease

Intercellular adhesion molecule 1 (ICAM-1/CD54), a transmembrane glycoprotein, has been considered as one of the most important adhesion molecules during leukocyte recruitment. It is encoded by the ICAM1 gene and plays a central role in inflammation. Its crucial role in many inflammatory diseases such as ulcerative colitis and rheumatoid arthritis are well established. Given that neuroinflammation, underscored by microglial activation, is a key element in neurodegenerative diseases such as Parkinson's disease (PD), we investigated whether ICAM-1 has a role in this progressive neurological condition and, if so, to elucidate the underpinning mechanisms. Specifically, we were interested in the potential interaction between ICAM-1, glial cells, and ferroptosis, an iron-dependent form of cell death that has recently been implicated in PD. We conclude that there exist direct and indirect (via glial cells and T cells) influences of ICAM-1 on ferroptosis and that further elucidation of these interactions can suggest novel intervention for this devastating disease.

Endothelial receptor proteins in acute venous thrombosis and delayed thrombus resolution in cerebral sinus vein thrombosis

BACKGROUND AND PURPOSE

Cerebral sinus venous thrombosis (CSVT) is a rare but life-threatening disease and its diagnosis remains challenging. Blood biomarkers, including D-Dimer are currently not recommended in guidelines. Soluble endothelial receptor proteins (sICAM-1, sPECAM-1 and sVCAM-1) have been shown to be promising diagnostic biomarkers in deep vein thrombosis (DVT) and pulmonary embolism (PE). Therefore, we examined endothelial receptor proteins as potential biomarkers for detecting CSVT.

METHODS

In this bi-centre, prospective study, we quantified D-Dimer as well as sICAM-1, sPECAM-1 and sVCAM-1 in plasma of patients with clinically suspected CSVT managed in the neurological emergency department (ED) of a tertiary care hospital. All patients underwent cerebral magnetic resonance imaging (MRI) and were followed up after 3, 6 and 12 months to detect thrombus resolution.

RESULTS

Twenty-four out of 75 (32%) patients with clinically suspected CSVT presenting with headache to the ED were diagnosed with acute CSVT. These patients had a mean age of 45 ± 16 years and 78% were female. In patients with CSVT, mean baseline D-dimer (p < 0.001) and sPECAM-1 (p < 0.001) were significantly higher compared to patients without CSVT. The combination of D-Dimer and sPECAM-1 yielded the best ROC-AUC (0.994; < 0.001) with a negative predictive value of 95.7% and a positive predictive value of 95.5%. In addition, higher baseline sPECAM-1 levels (> 198 ng/ml) on admission were associated with delayed venous thrombus resolution at 3 months (AUC = 0.83).

CONCLUSION

sPECAM-1 in combination with D-Dimer should be used to improve the diagnostic accuracy of acute CSVT and sPECAM-1 may predict long-term outcome of CSVT. Confirmatory results are needed in other settings in order to show their value in the management concept of CSVT patients.

Vasculature organotropism in drug delivery

Over the past decades, there has been an exponential increase in the development of preclinical and clinical nanodelivery systems, and recently, an accelerating demand to deliver RNA and protein-based therapeutics. Organ-specific vasculature provides a promising intermediary for site-specific delivery of nanoparticles and extracellular vesicles to interstitial cells. Endothelial cells express organ-specific surface marker repertoires that can be used for targeted delivery. This article highlights organ-specific vasculature properties, nanodelivery strategies that exploit vasculature organotropism, and overlooked challenges and opportunities in targeting and simultaneously overcoming the endothelial barrier. Impediments in the clinical translation of vasculature organotropism in drug delivery are also discussed.

Peripheralization Strategies Applied to Morphinans and Implications for Improved Treatment of Pain

Opioids are considered the most effective analgesics for the treatment of moderate to severe acute and chronic pain. However, the inadequate benefit/risk ratio of currently available opioids, together with the current 'opioid crisis', warrant consideration on new opioid analgesic discovery strategies. Targeting peripheral opioid receptors as effective means of treating pain and avoiding the centrally mediated side effects represents a research area of substantial and continuous attention. Among clinically used analgesics, opioids from the class of morphinans (i.e., morphine and structurally related analogues) are of utmost clinical importance as analgesic drugs activating the mu-opioid receptor. In this review, we focus on peripheralization strategies applied to N-methylmorphinans to limit their ability to cross the blood-brain barrier, thus minimizing central exposure and the associated undesired side effects. Chemical modifications to the morphinan scaffold to increase hydrophilicity of known and new opioids, and nanocarrier-based approaches to selectively deliver opioids, such as morphine, to the peripheral tissue are discussed. The preclinical and clinical research activities have allowed for the characterization of a variety of compounds that show low central nervous system penetration, and therefore an improved side effect profile, yet maintaining the desired opioid-related antinociceptive activity. Such peripheral opioid analgesics may represent alternatives to presently available drugs for an efficient and safer pain therapy.

The effects of probiotics on VCAM-1 and ICAM-1: A systematic review and meta-analysis of randomized controlled trials

BACKGROUND

We performed the present systematic review and meta-analysis of randomized controlled trials (RCTs) to evaluate the effects of probiotics on intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) levels in adults.

METHODS

A systematic search current to April 2022 was performed in MEDLINE, EMBASE, and Cochrane Database using relevant keywords to detect eligible articles. A random-effects model was used to estimate the standardized mean difference (SMD) and 95% confidence interval (95% CI).

RESULTS

Six eligible trials were included in the final analysis. The pooled analysis revealed that there was a significant reduction in VCAM-1 from baseline to post-probiotic course with standardized mean difference [SMD: -0.66 ng/ml; 95% CI: -1.09, -0.23 ng/ml; P = 0.003]. The effects of probiotic intake on VCAM-1 were more pronounced when it was received via supplements [SMD: -0.61 ng/ml; 95% CI: -1.08, -0.14 ng/ml; P = 0.010], for 12 weeks [SMD: -0.60 ng/ml; 95% CI: -1.09, -0.12 ng/ml; P = 0.014] and when it was prescribed for individuals with metabolic syndrome [SMD: -0.79 ng/ml; 95% CI: -1.40, -0.19 ng/ml; P = 0.010]. Moreover, VCAM-1 levels were decreased in the subgroup of multispecies probiotic regiments [SMD: -0.71 ng/ml; 95% CI: -1.38, -0.04 ng/ml; P = 0.039].

CONCLUSION

Our study demonstrates potential beneficial effects of probiotics on VCAM-1 in adults. However, more larger-scale, long-time RCTs are needed to confirm the accurate effect of probiotics on endothelial dysfunction biomarkers.

Gene regulation of intracellular adhesion molecule-1 (ICAM-1): A molecule with multiple functions

Intracellular adhesion molecule 1 (ICAM-1) is one of the most extensively studied inducible cell adhesion molecules which is responsible for several immune functions like T cell activation, extravasation, inflammation, etc. The molecule is constitutively expressed over the cell surface and is regulated up / down in response to inflammatory mediators like cellular stress, proinflammatory cytokines, viral infection. These stimuli modulate the expression of ICAM-1 primarily through regulating the ICAM-1 gene transcription. On account of the presence of various binding sites for NF-κB, AP-1, SP-1, and many other transcription factors, the architecture of the ICAM-1 promoter become complex. Transcription factors in union with other transcription factors, coactivators, and suppressors promote their assembly in a stereospecific manner on ICAM-1 promoter which mediates ICAM-1 regulation in response to different stimuli. Along with transcriptional regulation, epigenetic modifications also play a pivotal role in controlling ICAM-1 expression on different cell types. In this review, we summarize the regulation of ICAM-1 expression both at the transcriptional as well as post-transcriptional level with an emphasis on transcription factors and signaling pathways involved.

Peripherally acting opioid analgesics and peripherally-induced analgesia

The management of pain, particularly chronic pain, is still an area of medical need. In this context, opioids remain a gold standard for the treatment of pain. However, significant side effects, mainly of central origin, limit their clinical use. Here, we review recent progress to improve the therapeutic and safety profiles of opioids for pain management. Characterization of peripheral opioid-mediated pain mechanisms have been a key component of this process. Several studies identified peripheral µ, δ, and κ opioid receptors (MOR, DOR, and KOR, respectively) and nociceptin/orphanin FQ (NOP) receptors as significant players of opioid-mediated antinociception, able to achieve clinically significant effects independently of any central action. Following this, particularly from a medicinal chemistry point of view, main efforts have been directed towards the peripheralization of opioid receptor agonists with the objective of optimizing receptor activity and minimizing central exposure and the associated undesired effects. These activities have allowed the characterization of a great variety of compounds and investigational drugs that show low central nervous system (CNS) penetration (and therefore a reduced side effect profile) yet maintaining the desired opioid-related peripheral antinociceptive activity. These include highly hydrophilic/amphiphilic and massive molecules unable to easily cross lipid membranes, substrates of glycoprotein P (a extrusion pump that avoids CNS penetration), nanocarriers that release the analgesic agent at the site of inflammation and pain, and pH-sensitive opioid agonists that selectively activate at those sites (and represent a new pharmacodynamic paradigm). Hopefully, patients with pain will benefit soon from the incorporation of these new entities.

Targeting drug delivery in the vascular system: Focus on endothelium

The bloodstream is the main transporting pathway for drug delivery systems (DDS) from the site of administration to the intended site of action. In many cases, components of the vascular system represent therapeutic targets. Endothelial cells, which line the luminal surface of the vasculature, play a tripartite role of the key target, barrier, or victim of nanomedicines in the bloodstream. Circulating DDS may accumulate in the vascular areas of interest and in off-target areas via mechanisms bypassing specific molecular recognition, but using ligands of specific vascular determinant molecules enables a degree of precision, efficacy, and specificity of delivery unattainable by non-affinity DDS. Three decades of research efforts have focused on specific vascular targeting, which have yielded a multitude of DDS, many of which are currently undergoing a translational phase of development for biomedical applications, including interventions in the cardiovascular, pulmonary, and central nervous systems, regulation of endothelial functions, host defense, and permeation of vascular barriers. We discuss the design of endothelial-targeted nanocarriers, factors underlying their interactions with cells and tissues, and describe examples of their investigational use in models of acute vascular inflammation with an eye on translational challenges.

Molecular Targeting of Immunosuppressants Using a Bifunctional Elastin-Like Polypeptide

Elastin-Like Polypeptides (ELP) are environmentally responsive protein polymers which are easy to engineer and biocompatible, making them ideal candidates as drug carriers. Our team has recently utilized ELPs fused to FKBP12 to carry Rapamycin (Rapa), a potent immunosuppressant. Through high affinity binding to Rapa, FKBP carriers can yield beneficial therapeutic effects and reduce the off-site toxicity of Rapa. Since ICAM-1 is significantly elevated at sites of inflammation in diverse diseases, we hypothesized that a molecularly targeted ELP carrier capable of binding ICAM-1 might have advantageous properties. Here we report on the design, characterization, pharmacokinetics, and biodistribution of a new ICAM-1-targeted ELP Rapa carrier (IBPAF) and its preliminary characterization in a murine model exhibiting elevated ICAM-1. Lacrimal glands (LG) of male NOD mice, a disease model recapitulating the autoimmune dacryoadenitis seen in Sjögren's Syndrome patients, were analyzed to confirm that ICAM-1 was significantly elevated in the LG relative to control male BALB/c mice (3.5-fold, p < 0.05, n = 6). In vitro studies showed that IBPAF had significantly higher binding to TNF-α-stimulated bEnd.3 cells which overexpress surface ICAM-1, relative to nontargeted control ELP (AF)(4.0-fold, p < 0.05). A pharmacokinetics study in male NOD mice showed no significant differences between AF and IBPAF for plasma half-life, clearance, and volume of distribution. However, both constructs maintained a higher level of Rapa in systemic circulation compared to free Rapa. Interestingly, in the male NOD mouse, the accumulation of IBPAF was significantly higher in homogenized LG extracts compared to AF at 2 h (8.6 ± 6.6% versus 1.3 ± 1.3%, respectively, n = 5, p < 0.05). This accumulation was transient with no differences detected at 8 or 24 h. This study describes the first ICAM-1 targeted protein-polymer carrier for Rapa that specifically binds to ICAM-1 in vitro and accumulates in ICAM-1 overexpressing tissue in vivo, which may be useful for molecular targeting in diverse inflammatory diseases where ICAM-1 is elevated.

Current Practices and Potential Nanotechnology Perspectives for Pain Related to Cystic Fibrosis

Pain is a complex, multidimensional process that negatively affects physical and mental functioning, clinical outcomes, quality of life, and productivity for cystic fibrosis (CF) patients. CF is an inherited multi-system disease that requires a complete approach in order to evaluate, monitor and treat patients. The landscape in CF care has changed significantly, with currently more adult patients than children worldwide. Despite the great advances in supportive care and in our understanding regarding its pathophysiology, there are still numerous aspects of CF pain that are not fully explained. This review aims to provide a critical overview of CF pain research that focuses on pain assessment, prevalence, characteristics, clinical association and the impact of pain in children and adults, along with innovative nanotechnology perspectives for CF management. Specifically, the paper evaluates the pain symptoms associated with CF and examines the relationship between pain symptoms and disease severity. The particularities of gastrointestinal, abdominal, musculoskeletal, pulmonary and chest pain, as well as pain associated with medical procedures are investigated in patients with CF. Disease-related pain is common for patients with CF, suggesting that pain assessment should be a routine part of their clinical care. A summary of the use of nanotechnology in CF and CF-related pain is also given. Further research is clearly needed to better understand the sources of pain and how to improve patients’ quality of life.

Hsa_circ_0005519 increases IL-13/IL-6 by regulating hsa-let-7a-5p in CD4+ T cells to affect asthma

BACKGROUND

Circular RNAs (circRNAs) are a class of non-coding RNAs that could serve as novel biomarkers for the diagnosis and treatment of diseases. We hypothesized that circRNAs of CD4⁺ T cells are involved in asthma.

OBJECTIVE

In this study, we investigated the circRNA expression profile and the possible mechanism by which hsa_circ_0005519 participates in asthma.

METHODS

The expression profiles of circRNAs in CD4⁺ T cells were revealed by circRNA microarray. Hsa_circ_0005519 expression in CD4⁺ T cells was confirmed in asthmatic patients (n = 65) and healthy subjects (n = 30). Hsa-let-7a-5p, the target of hsa_circ_0005519, was predicted by online algorithms and verified by a dual-luciferase reporter assay. Correlation assays between the expression of hsa_circ_0005519 and hsa-let-7a-5p, the mRNA levels of interleukin (IL)-13 and IL-6 in CD4⁺ T cells, and the clinical characteristics of asthmatic patients were performed. The role of hsa_circ_0005519 in proinflammatory cytokine expression was investigated in CD4⁺ T cells from asthmatic patients in vitro. Hsa_circ_0005519 expression in PBMCs was determined in another cohort including 30 asthmatic patients and 24 controls. Correlation assays of hsa_circ_0005519 expressions between CD4⁺ T cells and PBMCs were performed.

RESULTS

Hsa_circ_0005519 was up-regulated and negatively correlated with hsa-let-7a-5p expression in CD4⁺ T cells of asthmatic patients. Both the fraction of exhaled nitric oxide (FeNO) and the peripheral blood eosinophil ratio were positively correlated with hsa_circ_0005519 expression in CD4⁺ T cells. These outcomes were also different in asthmatic patients with low vs high hsa_circ_0005519 levels. Hsa_circ_0005519 expressions between CD4⁺ T cells and PBMCs were concordant in asthmatic patients. Mechanistically, hsa_circ_0005519 might bind to hsa-let-7a-5p and relieve suppression for IL-13/IL-6 in CD4⁺ T cells.

CONCLUSIONS AND CLINICAL RELEVANCE

Our data suggest that hsa_circ_0005519 may induce IL-13 and IL-6 expression by regulating hsa-let-7a-5p in CD4⁺ T cells to affect asthma. And hsa_circ_0005519 may be a potential biomarker of asthma.

Bio-inspired engineering of cell- and virus-like nanoparticles for drug delivery

The engineering of future generations of nanodelivery systems aims at the creation of multifunctional vectors endowed with improved circulation, enhanced targeting and responsiveness to the biological environment. Moving past purely bio-inert systems, researchers have begun to create nanoparticles capable of proactively interacting with the biology of the body. Nature offers a wide-range of sources of inspiration for the synthesis of more effective drug delivery platforms. Because the nano-bio-interface is the key driver of nanoparticle behavior and function, the modification of nanoparticles' surfaces allows the transfer of biological properties to synthetic carriers by imparting them with a biological identity. Modulation of these surface characteristics governs nanoparticle interactions with the biological barriers they encounter. Building off these observations, we provide here an overview of virus- and cell-derived biomimetic delivery systems that combine the intrinsic hallmarks of biological membranes with the delivery capabilities of synthetic carriers. We describe the features and properties of biomimetic delivery systems, recapitulating the distinctive traits and functions of viruses, exosomes, platelets, red and white blood cells. By mimicking these biological entities, we will learn how to more efficiently interact with the human body and refine our ability to negotiate with the biological barriers that impair the therapeutic efficacy of nanoparticles.

Nanotechnology application for pain therapy

Prolonged delivery of analgesic drugs at target sites remains a critical issue for efficient pain management. The use of nano-carriers has been reported to facilitate applicable delivery of these agents to target sites with a reduced level of systemic toxicity. Different analgesics have been loaded onto various nano carriers, including those that are natural, synthetic and copolymer, for various medical applications. In this review, we will discuss the concept of nano-formulated carriers for analgesic drugs and their impacts on the field of pain management.

Pharmacological Tools to Activate Microglia and their Possible use to Study Neural Network Patho-physiology

BACKGROUND

Microglia are the resident immunocompetent cells of the CNS and also constitute a unique cell type that contributes to neural network homeostasis and function. Understanding microglia cell-signaling not only will reveal their diverse functions but also will help to identify pharmacological and non-pharmacological tools to modulate the activity of these cells.

METHODS

We undertook a search of bibliographic databases for peer-reviewed research literature to identify microglial activators and their cell-specificity. We also looked for their effects on neural network function and dysfunction.

RESULTS

We identified several pharmacological targets to modulate microglial function, which are more or less specific (with the proper control experiments). We also identified pharmacological targets that would require the development of new potent and specific modulators. We identified a wealth of evidence about the participation of microglia in neural network function and their alterations in pathological conditions.

CONCLUSION

The identification of specific microglia-activating signals provides experimental tools to modulate the activity of this heterogeneous cell type in order to evaluate its impact on other components of the nervous system, and it also helps to identify therapeutic approaches to ease some pathological conditions related to microglial dysfunction.

P-Selectin Targeted Dexamethasone-Loaded Lipid Nanoemulsions: A Novel Therapy to Reduce Vascular Inflammation

Inflammation is a common process associated with numerous vascular pathologies. We hypothesized that targeting the inflamed endothelium by coupling a peptide with high affinity for P-selectin to the surface of dexamethasone-loaded lipid nanoemulsions will highly increase their specific binding to activated endothelial cells (EC) and reduce the cell activation. We developed and characterized dexamethasone-loaded lipid nanoemulsions directed towards P-selectin (PLN-Dex) and monitored their anti-inflammatory effects in vitro using cultured EC (EA.hy926 cells) and in vivo using a mouse model of acute inflammation [lipopolysaccharides (LPS) intravenously administered in C57BL/6 mice]. We found that PLN-Dex bound specifically to the surface of activated EC are efficiently internalized by EC and reduced the expression of proinflammatory genes, thus preventing the monocyte adhesion and transmigration to/through activated EC. Given intravenously in mice with acute inflammation, PLN-Dex accumulated at a significant high level in the lungs (compared to nontargeted nanoemulsions) and significantly reduced mRNA expression level of key proinflammatory cytokines such as IL-1β, IL-6, and MCP-1. In conclusion, the newly developed nanoformulation, PLN-Dex, is functional in vitro and in vivo, reducing selectively the endothelium activation and the consequent monocyte infiltration and diminishing significantly the lungs' inflammation, in a mouse model of acute inflammation.

Neuroimmune Interaction in the Regulation of Peripheral Opioid-Mediated Analgesia in Inflammation

Peripheral immune cell-mediated analgesia in inflammation is an important endogenous mechanism of pain control. Opioid receptors localized on peripheral sensory nerve terminals are activated by endogenous opioid peptides released from immune cells to produce significant analgesia. Following transendothelial migration of opioid-containing leukocytes into peripheral sites of inflammation, opioid peptides are released into a harsh milieu associated with an increase in temperature, low pH, and high proteolytic activity. Together, this microenvironment has been suggested to increase the activity of opioid peptide metabolism. Therefore, the proximity of immune cells and nerve fibers may be essential to produce adequate analgesic effects. Close associations between opioid-containing immune cells and peripheral nerve terminals have been observed. However, it is not yet determined whether these immune cells actually form synaptic-like contacts with peripheral sensory terminals and/or whether they secrete opioids in a paracrine manner. This review will provide novel insight into the peripheral mechanisms of immune-derived analgesia in inflammation, in particular, the importance of direct interactions between immune cells and the peripheral nervous system.

VEGFR-2 Expression in Glioblastoma Multiforme Depends on Inflammatory Tumor Microenvironment

Glioblastoma multiforme (GBM) is one of the most angiogenic tumors. However, antiangiogenic therapy has not shown significant clinical efficacy. The aim of our study was to evaluate the impact of inflammatory tumor microenvironment on the expression of vascular endothelial growth factor receptor 2 (VEGFR-2). Surgically excised primary GBM tissues were histologically examined for overall extent of inflammation (score 1-3). After immunohistochemistry, the tissue expression of ICAM-1 (optical density), the number of VEGFR-2 positive (VEGFR-2+) blood vessels (per microscopic field), and the endothelial staining intensity of VEGFR-2 (score 0-3) were determined. In GBM, the extent of inflammation was 1.9 ± 0.7 (group mean ± SD). Mean optical density of inflammatory mediator ICAM-1 was 57.0 ± 27.1 (pixel values). The number of VEGFR-2+ blood vessels and endothelial VEGFR-2 staining intensity were 6.2 ± 2.4 and 1.2 ± 0.8, respectively. A positive association was found between endothelial VEGFR-2 staining intensity and the extent of inflammation (p = 0.005). Moreover, VEGFR-2 staining intensity correlated with the expression level of ICAM-1 (p = 0.026). The expression of VEGFR-2, one of the main targets of antiangiogenic therapy, depends on GBM microenvironment. Higher endothelial VEGFR-2 levels were seen in the presence of more pronounced inflammation. Target dependence on inflammatory tumor microenvironment has to be taken into consideration when treatment approaches that block VEGFR-2 signaling are designed.

Targeted endothelial nanomedicine for common acute pathological conditions

Endothelium, a thin monolayer of specialized cells lining the lumen of blood vessels is the key regulatory interface between blood and tissues. Endothelial abnormalities are implicated in many diseases, including common acute conditions with high morbidity and mortality lacking therapy, in part because drugs and drug carriers have no natural endothelial affinity. Precise endothelial drug delivery may improve management of these conditions. Using ligands of molecules exposed to the bloodstream on the endothelial surface enables design of diverse targeted endothelial nanomedicine agents. Target molecules and binding epitopes must be accessible to drug carriers, carriers must be free of harmful effects, and targeting should provide desirable sub-cellular addressing of the drug cargo. The roster of current candidate target molecules for endothelial nanomedicine includes peptidases and other enzymes, cell adhesion molecules and integrins, localized in different domains of the endothelial plasmalemma and differentially distributed throughout the vasculature. Endowing carriers with an affinity to specific endothelial epitopes enables an unprecedented level of precision of control of drug delivery: binding to selected endothelial cell phenotypes, cellular addressing and duration of therapeutic effects. Features of nanocarrier design such as choice of epitope and ligand control delivery and effect of targeted endothelial nanomedicine agents. Pathological factors modulate endothelial targeting and uptake of nanocarriers. Selection of optimal binding sites and design features of nanocarriers are key controllable factors that can be iteratively engineered based on their performance from in vitro to pre-clinical in vivo experimental models. Targeted endothelial nanomedicine agents provide antioxidant, anti-inflammatory and other therapeutic effects unattainable by non-targeted counterparts in animal models of common acute severe human disease conditions. The results of animal studies provide the basis for the challenging translation endothelial nanomedicine into the clinical domain.

Beneficial Effects of Coenzyme Q10 Supplementation on Lipid Profile and Intereukin-6 and Intercellular Adhesion Molecule-1 Reduction, Preliminary Results of a Double-blind Trial in Acute Myocardial Infarction

Background:

The present investigation was aimed to improve the inflammatory factors and lipoproteins concentration in patients with myocardial infarction (MI) by supplementation with coenzyme Q10 (CoQ10).

Methods:

In a double-blind, placebo-controlled study, we measured serum concentrations of one soluble cell adhesion molecules (intercellular adhesion molecule-1 [ICAM-1]), serum concentration of intereukin-6 (IL-6) and lipid profiles (high-density lipoprotein-cholesterol [HDL-C], low-density lipoprotein-cholesterol [LDL-C], total cholesterol and triglyceride [TG]) in CoQ10 supplementation group (n = 26) compared with placebo group (n = 26) in hyperlipidemic patients with MI. Fifty-two patients were randomized to receive 200 mg/day of CoQ10 or placebo for 12 weeks.

Results:

There were no significant differences for serum LDL-C, total cholesterol, and TG between two mentioned groups after the intervention. A significant enhancement in serum HDL-C level was observed between groups after the intervention (55.46 ± 6.87 and 44.07 ± 6.99 mg/dl in CoQ10 and placebo groups, respectively P < 0.001). Concentrations of ICAM-1 (415.03 ± 96.89 and 453.38 ± 0.7 ng/dl CoQ10 and placebo groups, respectively, P = 0.001) and IL-6 (11 ± 9.57 and 12.55 ± 8.76 pg/ml CoQ10 and placebo groups, respectively P = 0.001) in serum were significantly decreased in CoQ10 group.

Conclusions:

Supplementation with CoQ10 in hyperlipidemic patients with MI that have statin therapy has beneficial effects on their aspects of health.

Noncoding RNAs, cytokines, and inflammation-related diseases

Chronic inflammation is involved in the onset and development of many diseases, including obesity, atherosclerosis, type 2 diabetes, osteoarthritis, autoimmune and degenerative diseases, asthma, periodontitis, and cirrhosis. The inflammation process is mediated by chemokines, cytokines, and different inflammatory cells. Although the molecules and mechanisms that regulate this primary defense mechanism are not fully understood, recent findings offer a putative role of noncoding RNAs, especially microRNAs (miRNAs), in the progression and management of the inflammatory response. These noncoding RNAs are crucial for the stability and maintenance of gene expression patterns that characterize some cell types, tissues, and biologic responses. Several miRNAs, such as miR-126, miR-132, miR-146, miR-155, and miR-221, have emerged as important transcriptional regulators of some inflammation-related mediators. Additionally, little is known about the involvement of long noncoding RNAs, long intergenic noncoding RNAs, and circular RNAs in inflammation-mediated processes and the homeostatic imbalance associated with metabolic disorders. These noncoding RNAs are emerging as biomarkers with diagnosis value, in prognosis protocols, or in the personalized treatment of inflammation-related alterations. In this context, this review summarizes findings in the field, highlighting those noncoding RNAs that regulate inflammation, with emphasis on recognized mediators such as TNF-α, IL-1, IL-6, IL-18, intercellular adhesion molecule 1, VCAM-1, and plasminogen activator inhibitor 1. The down-regulation or antagonism of the noncoding RNAs and the administration of exogenous miRNAs could be, in the near future, a promising therapeutic strategy in the treatment of inflammation-related diseases.

Inhalative IL-10 treatment after bilateral femoral fractures affect pulmonary inflammation in mice

BACKGROUND

Musculoskeletal injuries induce systemic inflammation which often impairs lung function contributing to morbidity. IL-10 has been shown to have a beneficial effect on immune dysfunction and organ damage after different traumatic insults. We sought to investigate the effect of inhalative IL-10 administration on the systemic and pulmonary inflammatory response in a small animal model of bilateral femoral fracture.

MATERIALS AND METHODS

Male C57/BL6 mice (6 animals per group) were subjected to bilateral femoral fracture and intramedullary nailing followed by inhalative administration of either 50μL PBS (Fx group) or 50μg/kg recombinant mouse IL-10 dissolved in 50μL PBS (FxIL-10 group). All animals were sacrificed at 6, 24, or 72h after fracture induction. Blood samples were collected and analyzed for IL-6, IL-10, KC, and MCP-1 (CCL2) plasma concentrations by Bio-Plex Pro™ assays. Pulmonary infiltration by neutrophils was assessed by myeloperoxidase (MPO) activity (ELISA) and histological analysis of lung tissue. Pulmonary ICAM-1 expression (immunohistochemistry), and pulmonary IL-6 levels (ELISA) were determined.

RESULTS

Inhalative IL-10 administration showed a decrease in the pulmonary infiltration by neutrophils. A significant decrease in the expression of the adhesion molecule ICAM-1 after local IL-10 application was observed. In contrast, local IL-10 administration did not show a significant effect on the systemic inflammatory response.

CONCLUSION

Our findings suggest that inhalative IL-10 administration may beneficially modulate the pulmonary microenvironment, in which IL-10 effect on the local ICAM-1 expression seems to play a central role.

Inflammation markers and their trajectories after deep vein thrombosis in relation to risk of post-thrombotic syndrome

BACKGROUND

Post-thrombotic syndrome (PTS) is a frequent chronic complication of deep vein thrombosis (DVT).

OBJECTIVE

In the BioSOX study, we investigated whether inflammation markers predict the risk of PTS after DVT.

METHODS

We measured C-reactive protein (CRP), ICAM-1, interleukin (IL)-6, and IL-10, at baseline, and 1 month and 6 months after a first proximal DVT, among 803 participants in the SOX trial. Participants were prospectively followed for 24 months for development of PTS.

RESULTS

Median CRP levels at 1 month, ICAM-1 levels at baseline, 1 month and 6 months, IL-6 levels at 1 month and 6 months and IL-10 levels at 6 months were higher in patients who developed PTS than in those who did not. Multivariable regression with the median as a cutoff showed risk ratios (RRs) for PTS of 1.23 (95% confidence interval [CI] 1.05-1.45) and 1.25 (95% CI 1.05-1.48) for ICAM-1 at 1 month and 6 months, respectively, and 1.27 (95% CI 1.07-1.51) for IL-10 at 6 months. Quartile-based analysis demonstrated a dose-response association between ICAM-1 and PTS. ICAM-1 and IL-10 were also associated with PTS severity. Analysis of biomarker trajectories after DVT demonstrated an association between the highest-trajectory group of ICAM-1 and PTS.

CONCLUSIONS

In this prospective study, ICAM-1 over time was most consistently associated with the risk of PTS. Further study is required to confirm these findings and assess their potential clinical relevance.

ICAM-1: isoforms and phenotypes

ICAM-1 plays an important role in leukocyte trafficking, immunological synapse formation, and numerous cellular immune responses. Although considered a single glycoprotein, there are multiple membrane-bound and soluble ICAM-1 isoforms that arise from alternative splicing and proteolytic cleavage during inflammatory responses. The function and expression of these isoforms on various cell types are poorly understood. In the generation of ICAM-1-deficient mice, two isoform-deficient ICAM-1 mutants were inadvertently produced as a result of alternative splicing. These mice, along with true ICAM-1-deficient mice and newly generated ICAM-1-transgenic mice, have provided the opportunity to begin examining the role of ICAM-1 isoforms (singly or in combination) in various disease settings. In this review, we highlight the sharply contrasting disease phenotypes using ICAM-1 isoform mutant mice. These studies demonstrate that ICAM-1 immunobiology is highly complex but that individual isoforms, aside from the full-length molecule, make significant contributions to disease development and pathogenesis.

Targeted thermosensitive liposomes: an attractive novel approach for increased drug delivery to solid tumors

INTRODUCTION

Currently available chemotherapy is hampered by a lack in tumor specificity and resulting toxicity. Small and long-circulating liposomes can preferentially deliver chemotherapeutic drugs to tumors upon extravasation from tumor vasculature. Although clinically used liposomal formulations demonstrated significant reduction in toxicity, enhancement of therapeutic activity has not fully met expectations.

AREAS COVERED

Low drug bioavailability from liposomal formulations and limited tumor accumulation remain major challenges to further improve therapeutic activity of liposomal chemotherapy. The aim of this review is to highlight strategies addressing these challenges. A first strategy uses hyperthermia and thermosensitive liposomes to improve tumor accumulation and trigger liposomal drug bioavailability. Image-guidance can aid online monitoring of heat and drug delivery and further personalize the treatment. A second strategy involves tumor-specific targeting to enhance drug delivery specificity and drug internalization. In addition, we review the potential of combinations of the two in one targeted thermosensitive-triggered drug delivery system.

EXPERT OPINION

Heat-triggered drug delivery using thermosensitive liposomes as well as the use of tumor vasculature or tumor cell-targeted liposomes are both promising strategies to improve liposomal chemotherapy. Preclinical evidence has been encouraging and both strategies are currently undergoing clinical evaluation. A combination of both strategies rendering targeted thermosensitive liposomes (TTSL) may appear as a new and attractive approach promoting tumor drug delivery.

The use of lipid-based nanocarriers for targeted pain therapies

Sustained delivery of analgesic agents at target sites remains a critical issue for effective pain management. The use of nanocarriers has been reported to facilitate effective delivery of these agents to target sites while minimizing systemic toxicity. These include the use of biodegradable liposomal or polymeric carriers. Of these, liposomes present as an attractive delivery system due to their flexible physicochemical properties which allow easy manipulation in order to address different delivery considerations. Their favorable toxicity profiles and ease of large scale production also make their clinical use feasible. In this review, we will discuss the concept of using liposomes as a drug delivery carrier, their in vitro characteristics as well as in vivo behavior. Current advances in the targeted liposomal delivery of analgesic agents and their impacts on the field of pain management will be presented.

Targeting peripheral opioid receptors to promote analgesic and anti-inflammatory actions

Mechanisms of endogenous pain control are significant. Increasing studies have clearly produced evidence for the clinical usefulness of opioids in peripheral analgesia. The immune system uses mechanisms of cell migration not only to fight pathogens but also to control pain and inflammation within injured tissue. It has been demonstrated that peripheral inflammatory pain can be effectively controlled by an interaction of immune cell-derived opioid peptides with opioid receptors on peripheral sensory nerve terminals. Experimental and clinical studies have clearly shown that activation of peripheral opioid receptors with exogenous opioid agonists and endogenous opioid peptides are able to produce significant analgesic and anti-inflammatory effects, without central opioid mediated side effects (e.g., respiratory depression, sedation, tolerance, dependence). This article will focus on the role of opioids in peripheral inflammatory conditions and the clinical implications of targeting peripheral opioid receptors.

Targeting sites of inflammation: intercellular adhesion molecule-1 as a target for novel inflammatory therapies

Targeted drug delivery to sites of inflammation will provide effective, precise, and safe therapeutic interventions for treatment of diverse disease conditions, by limiting toxic side effects and/or increasing drug action. Disease-site targeting is believed to play a major role in the enhanced efficacy observed for a variety of drugs when formulated inside lipid vesicles. This article will focus on the factors and mechanisms involved in drug targeting to sites of inflammation and the importance of cell adhesion molecules, in particular intercellular adhesion molecule-1, in this process.

Targeting of ICAM-1-directed immunoliposomes specifically to activated endothelial cells with low cellular uptake: use of an optimized procedure for the coupling of low concentrations of antibody to liposomes

Targeted delivery of therapeutics to the endothelium is an important goal in the treatment of inflammatory diseases. The aim of this work was to exploit the overexpression of intercellular adhesion molecule-1 (ICAM-1) on activated endothelial cells for the targeting of anti-ICAM-1-coupled immunoliposomes with the intent for further use as drug carriers. Immunoliposomes were prepared from using an optimized method for the coupling of low concentrations of antibody to liposomes, thereby preventing the loss of antibody through the derivatization, extraction, and activation process. This is especially suitable for limiting ligand conjugates that are isolated or synthesized in small quantities, such as monoclonal antibodies (mAbs). To investigate the functionality of the resulting immunoliposomes, the specificity of binding and cellular internalization studies of liposomes, either nonconjugated or conjugated with mAbs to ICAM-1 or to irrelevant IgG to high endothelial venule (HEV) cells, were analyzed by fluorescence microplate spectroscopy at 4 and 37°C. Immunoliposomes specifically directed against ICAM-1 were shown to bind selectively and specifically to tumor necrosis factor alpha-activated endothelial cells in vitro, with minimal cellular internalization. This study provides a novel delivery system that has the potential for targeting therapeutics to inflammatory tissue.

Targeted drug-delivery approaches by nanoparticulate carriers in the therapy of inflammatory diseases

Limitations in therapy induced by adverse effects due to unselective drug availability and therefore the use of potentially too high doses are a common problem. One prominent example for this dilemma are inflammatory diseases. Colloidal carriers allow one to improve delivery of drugs to the site of action and appear promising to overcome this general therapeutic drawback. Specific uptake of nanoparticles by immune-related cells in inflamed barriers offers selective drug targeting to the inflamed tissue. Here we focus on nanocarrier-based drug delivery strategies for the treatment of common inflammatory disorders like rheumatoid arthritis, multiple sclerosis, uveitis or inflammatory bowel disease.

Targeting of angiogenic endothelial cells at sites of inflammation by dexamethasone phosphate-containing RGD peptide liposomes inhibits experimental arthritis

OBJECTIVE

To investigate whether RGD peptide-exposing long circulating polyethylene glycol (PEG) liposomes (RGD-PEG-L) targeted to alphavbeta3 integrins expressed on angiogenic vascular endothelial cells (VECs) are able to bind VECs at sites of inflammation and whether such liposomes containing dexamethasone phosphate (DEXP) can be used as carriers to interfere with the development of experimental arthritis.

METHODS

Binding and internalization of RGD-PEG-L were studied by fluorescence-activated cell sorting and confocal microscopy using fluorescently labeled liposomes. Radiolabeled liposomes were used to test in vivo pharmacokinetics and inflammation site targeting in lipopolysaccharide (LPS)-induced inflammation and adjuvant-induced arthritis (AIA) in rats. In vivo inflammation targeting was visualized by intravital microscopy using fluorescently labeled RGD-PEG-L. Therapeutic efficacy of DEXP-encapsulating RGD-PEG-L compared with nontargeted liposomes was evaluated in rats with AIA.

RESULTS

RGD-PEG-L bound to and were taken up by proliferating human VECs in vitro. In vivo, increased targeting of radiolabeled RGD-PEG-L to areas of LPS-induced inflammation in rats was observed. Specific association with the blood vessel wall at the site of inflammation was confirmed by intravital microscopy. One single intravenous injection of DEXP encapsulated in RGD-PEG-L resulted in a strong and long-lasting antiarthritic effect in rat AIA.

CONCLUSION

RGD-targeted PEG liposomes represent an endothelial cell-specific drug delivery system that targets VECs at sites of inflammation. Use of these liposomes to deliver DEXP to VECs at arthritis-affected sites proved efficacious in rat adjuvant arthritis. These data indicate that VECs have an essential role in the inflammation process and suggest the possibility of using VEC targeting for therapeutic intervention in inflammatory processes such as arthritis.

Lipid-based nanoparticles for contrast-enhanced MRI and molecular imaging

In the field of MR imaging and especially in the emerging field of cellular and molecular MR imaging, flexible strategies to synthesize contrast agents that can be manipulated in terms of size and composition and that can be easily conjugated with targeting ligands are required. Furthermore, the relaxivity of the contrast agents, especially for molecular imaging applications, should be very high to deal with the low sensitivity of MRI. Lipid-based nanoparticles, such as liposomes or micelles, have been used extensively in recent decades as drug carrier vehicles. A relatively new and promising application of lipidic nanoparticles is their use as multimodal MR contrast agents. Lipids are amphiphilic molecules with both a hydrophobic and a hydrophilic part, which spontaneously assemble into aggregates in an aqueous environment. In these aggregates, the amphiphiles are arranged such that the hydrophobic parts cluster together and the hydrophilic parts face the water. In the low concentration regime, a wide variety of structures can be formed, ranging from spherical micelles to disks or liposomes. Furthermore, a monolayer of lipids can serve as a shell to enclose a hydrophobic core. Hydrophobic iron oxide particles, quantum dots or perfluorocarbon emulsions can be solubilized using this approach. MR-detectable and fluorescent amphiphilic molecules can easily be incorporated in lipidic nanoparticles. Furthermore, targeting ligands can be conjugated to lipidic particles by incorporating lipids with a functional moiety to allow a specific interaction with molecular markers and to achieve accumulation of the particles at disease sites. In this review, an overview of different lipidic nanoparticles for use in MRI is given, with the main emphasis on Gd-based contrast agents. The mechanisms of particle formation, conjugation strategies and applications in the field of contrast-enhanced, cellular and molecular MRI are discussed.

Liposomes in the treatment of inflammatory disorders

This review focuses on the therapeutic utility of liposomes in the treatment of inflammatory disorders, and aims to offer the reader an overview of the in vivo results obtained with liposomally encapsulated anti-inflammatory and immune suppressive drugs. The past 30 years has clearly indicated the added value of liposomes in the search for solutions for the delivery problems encountered. However, only a few liposomal anti-inflammatory therapeutics have entered the clinic. Reasons for the hurdles existing in the translation of promising preclinical findings to clinical studies are discussed.

Endothelial dysfunction and inflammatory process in transfusion-dependent patients with beta-thalassemia major

BACKGROUND

Beta-thalassemia major is associated with increased cardiovascular risk, although the underlying mechanisms remain unclear. We examined endothelial function and serum levels of inflammatory mediators in transfusion-dependent patients with beta-thalassemia major.

METHODS

The study population consisted of 67 patients with homozygous beta-thalassemia major, (aged 24.6+/-0.7 years) and 71 healthy age and sex matched controls. Forearm blood flow was measured with gauge-strain plethysmography. Forearm vasodilatory response to reactive hyperemia (RH%) or to nitrate (NTG%) was expressed as the percentage change of forearm blood flow from baseline to the maximum flow during reactive hyperemia or sublingual nitroglycerin, respectively. Serum levels of interleukin 6 (IL-6), soluble vascular cell adhesion molecule (sVCAM-1) and soluble intercellular adhesion molecule (sICAM-1) were determined with ELISA.

RESULTS

Patients had significantly lower levels of total cholesterol (125+/-4.5 vs. 207+/-7 mg/ml, p<0.01), ApoA1 (120+/-3 vs. 129+/-5 mg/ml, p<0.05), ApoB (60.5+/-2 vs. 95+/-4 mg/ml, p<0.01), ApoE (3+/-2 vs. 4+/-0.2 mg/ml, p<0.01) and Lp(a) (7.9+/-1.3 vs. 14.5+/-3.2 mg/ml, p<0.01) than controls. IL-6 levels were significantly higher in patients (3.03+/-0.31 pg/ml) than controls (1.15+/-0.15 pg/ml, p<0.01). Similarly, sVCAM-1 and sICAM-1 levels were significantly higher in patients (513+/-31 and 368+/-25.5 ng/ml, respectively) than controls (333+/-13.8 and 272+/-14.05 ng/ml, respectively, p<0.01 for both). Maximum hyperemic forearm blood flow and RH% were lower in patients (7.1+/-0.3 ml/100 ml tissue/min and 49+/-2.8%, respectively) than controls (8.26+/-0.32 ml/100 ml tissue/min and 86.3+/-5.57%, respectively, p<0.01 for both).

CONCLUSIONS

Beta-thalassemia major is associated with impaired endothelial function and increased levels of IL-6, sVCAM-1 and sICAM-1, suggesting a potential role of inflammation and endothelial dysfunction in the complications of the disease.

Targeting liposomes to tumor endothelial cells for neutron capture therapy

The aim of our work is to target (10)B to the tumor vasculature for neutron capture therapy (NCT). Alpha (v)-integrin specific RGD-peptides were coupled to liposomes that encapsulated dodecahydrododecaborate. These RGD-liposomes strongly associated with human umbilical vein endothelial cells (HUVEC) expressing this integrin and were internalized. Proliferating HUVEC proved sensitive to treatment with gamma-irradiation resulting in decreased cell viability and pronounced inhibition of DNA-synthesis with increasing dose. Irradiation of RGD-(10)B-liposome incubated HUVEC with neutrons strongly inhibited endothelial cell viability. These results suggest that efficient NCT can be achieved by targeting (10)B-liposomes to angiogenic endothelium in tumors.

Endothelium-Targeted Gene and Cell-Based Therapies for Cardiovascular Disease

Most common cardiovascular diseases are accompanied by endothelial dysfunction. Because of its predominant role in the pathogenesis of cardiovascular disease, the vascular endothelium is an attractive therapeutic target. The identification of promoter sequences capable of rendering endothelial-specific transgene expression together with the recent development of vectors with enhanced tropism for endothelium may offer opportunities for the design of new strategies for modulation of endothelial function. Such strategies may be useful in the treatment of chronic diseases such as hypertension, atherosclerosis, and ischemic artery disease, as well as in acute myocardial infarction and during open heart surgery for prevention of ischemia and reperfusion (I/R)-induced injury. The recent identification of putative endothelial progenitor cells in peripheral blood may allow the design of autologous cell-based strategies for neovascularization of ischemic tissues and for the repair of injured blood vessels and bioengineering of vascular prosthesis. "Proof-of-concept" for some of these strategies has been established in animal models of cardiovascular disease. However the successful translation of these novel strategies into clinical application will require further developments in vector and delivery technologies. Further characterization of the processes involved in mobilization, migration, homing, and incorporation of endothelial progenitor cells into the target tissues is necessary, and the optimal conditions for therapeutic application of these cells need to be defined and standardized.

New strategy for transfection: mixtures of medium-chain and long-chain cationic lipids synergistically enhance transfection

To date, the primary approach to improve the transfection properties of cationic lipids has been the synthesis of new kinds of cationic amphipaths or the inclusion of noncationic helper lipids. Here, it is reported that an alternative approach can be unusually effective, namely, the combination of two cationic lipid derivatives having the same head group but tails of different chain lengths. Particularly efficient was the combination of dilauroyl (12 carbon chain) and dioleoyl (18 carbon chain) homologues of O-ethylphosphatidylcholine. This mixture transfected DNA into human umbilical artery endothelial cells (HUAEC) more than 30-fold more efficiently than either compound separately. A unique advantage of this kind of combination agent is that transfection can be optimized either in the presence or absence of serum by adjusting the component ratio.

Oligoclonal T-cell populations in an inflammatory pseudotumor of the pancreas possibly related to autoimmune pancreatitis: an immunohistochemical and molecular analysis

Inflammatory pseudotumors (IPT), also known as inflammatory myofibroblastic tumors (IMT), are benign inflammatory processes that may have an infectious etiology and are very rare in the pancreatico-biliary region. Recent studies suggest a biological distinction between IPT and IMT, the latter being a true neoplastic process. We describe a case of pancreatic IPT, originally diagnosed as malignancy, which presumably recurred 4 months after the operation. Histologically, the tumor consisted of a smooth muscle actin and CD68-positive spindle cell population and a more abundant mononuclear inflammatory cell population, primarily composed of macrophages and T-lymphocytes. Inflammatory cells were the source of connective tissue growth factor and transforming growth factor-beta1 and tended to accumulate around nerves and blood vessels, as well as around residual pancreatic parenchymal elements, where an intense angiogenetic response was detected. Comparative genomic hybridization analysis of the tumor showed no chromosomal imbalances. Polymerase chain reaction-based analysis of T-cell receptor gamma gene rearrangement revealed an oligoclonal pattern. These findings suggest that the pathogenesis of aggressive cases of IPT could be related to the development of an intense and self-maintaining immune response, with the emergence of clonal populations of T-lymphocytes. The relation of the pancreatic IPT to autoimmune pancreatitis is emphasized.

Computer modeling of promoter organization as a tool to study transcriptional coregulation

Understanding how the regulation of gene networks is orchestrated is an important challenge for characterizing complex biological processes. Gene transcription is regulated in part by nuclear factors that recognize short DNA sequence motifs, called transcription factor binding sites, in most cases located upstream of the gene coding sequence in promoter and enhancer regions. Genes expressed in the same tissue under similar conditions often share a common organization of at least some of these regulatory binding elements. In this way the organization of promoter motifs represents a "footprint" of the transcriptional regulatory mechanisms at work in a specific biologic context and thus provides information about signal and tissue specific control of expression. Analysis of promoters for organizational features as demonstrated here provides a crucial link between the static nucleotide sequence of the genome and the dynamic aspects of gene regulation and expression.

In vitro cellular handling and in vivo targeting of E-selectin-directed immunoconjugates and immunoliposomes used for drug delivery to inflamed endothelium

PURPOSE

Drug targeting to activated endothelial cells is now being explored as a new approach to interfere with chronic inflammation. This study compares a dexamethasone-anti-E-selectin immunoconjugate (dexa-AbEsel) with anti-E-selectin immunoliposomes (AbEsel-immunoliposomes) that contain dexamethasone, regarding in vitro binding and internalization as well as in vivo accumulation in activated endothelial cells.

METHODS

In vitro binding and internalization of dexa-AbEsel and the AbEsel-immunoliposomes into TNFalpha-activated HUVECs was studied using confocal laser scanning microscopy and radiolabeled compounds. Tissue accumulation of both compounds was studied in a murine delayed-type hypersensitivity model using immunohistochemistry.

RESULTS AND CONCLUSIONS

Both preparations were selectively internalized by activated endothelial cells. Dexa-AbEsel was internalized by activated HUVECs to a larger extent than the AbEsel-immunoliposomes, although in theory the high drug-loading capacity of the liposomes may enable a larger amount of dexamethasone to be delivered intracellularly. Both dexa-AbEsel and AbEsel-immunoliposomes accumulated in activated endothelial cells in murine inflamed skin. AbEsel-immunoliposomes, but not dexa-AbEsel, were additionally detected in control skin, though to a lesser extent, and in macrophages of the liver and the spleen. Studies on therapeutic effects and side effects in models of chronic inflammation are now necessary to establish pharmacodynamics of dexa-AbEsel and/or AbEsel-immunoliposomes in the treatment of chronic inflammation.