Anti-inflammatory Therapeutics Research Articles

Addressing a broken drug pipeline for preterm birth: why early preterm birth is an orphan disease

Preterm birth remains one of the most urgent unresolved medical problems in obstetrics, yet only 2 therapeutics for preventing preterm birth have ever been approved by the United States Food and Drug Administration, and neither remains on the market. The recent withdrawal of 17-hydroxyprogesterone caproate (17-OHPC, Makena) marks a new but familiar era for obstetrics with no Food and Drug Administration-approved pharmaceuticals to address preterm birth. The lack of pharmaceuticals reflects a broad and ineffective pipeline hindered by extensive regulatory hurdles, soaring costs of performing drug research, and concerns regarding adverse effects among a particularly vulnerable population. The pharmaceutical industry has historically limited investments in research for diseases with similarly small markets, such as cystic fibrosis, given their rarity and diminished projected financial return. The Orphan Drug Act, however, incentivizes drug development for "orphan diseases", defined as affecting <200,000 people in the United States annually. Although the total number of preterm births in the United States exceeds this threshold annually, the early subset of preterm birth (<34 weeks' gestation) would qualify, which is predominantly caused by inflammation and infection. The scientific rationale for classifying preterm birth into early and late subsets is strong given that their etiologies differ, and therapeutics that may be efficacious for one subset may not work for the other. For example, antiinflammatory therapeutics would be expected to be highly effective for early but not late preterm birth. A robust therapeutic pipeline of antiinflammatory drugs already exists, which could be used to target spontaneous early preterm birth, in combination with antibiotics shown to sterilize the amniotic cavity. New applications for therapeutics targeting spontaneous early preterm birth could categorize as orphan disease drugs, which could revitalize the preterm birth therapeutic pipeline. Herein, we describe why drugs targeting early preterm birth should qualify for orphan status, which may increase pharmaceutical interest for this vitally important obstetrical condition.

Engineering broad-spectrum inhibitors of inflammatory chemokines from subclass A3 tick evasins

Chemokines are key regulators of leukocyte trafficking and attractive targets for anti-inflammatory therapy. Evasins are chemokine-binding proteins from tick saliva, whose application as anti-inflammatory therapeutics will require manipulation of their chemokine target selectivity. Here we describe subclass A3 evasins, which are unique to the tick genus Amblyomma and distinguished from “classical” class A1 evasins by an additional disulfide bond near the chemokine recognition interface. The A3 evasin EVA-AAM1001 (EVA-A) bound to CC chemokines and inhibited their receptor activation. Unlike A1 evasins, EVA-A was not highly dependent on N- and C-terminal regions to differentiate chemokine targets. Structures of chemokine-bound EVA-A revealed a deep hydrophobic pocket, unique to A3 evasins, that interacts with the residue immediately following the CC motif of the chemokine. Mutations to this pocket altered the chemokine selectivity of EVA-A. Thus, class A3 evasins provide a suitable platform for engineering proteins with applications in research, diagnosis or anti-inflammatory therapy.

Hepatitis E virus infection remodels the mature tRNAome in macrophages to orchestrate NLRP3 inflammasome response

Hepatitis E virus (HEV) infection has been shown to activate NOD-like receptor family pyrin domain-containing 3 (NLRP3) inflammasome in macrophages, a key mechanism of causing pathological inflammation, but the mechanisms regulating this response remain poorly understood. Here, we report that the mature tRNAome dynamically responds to HEV infection in macrophages. This directs IL-1β expression, the hallmark of NLRP3 inflammasome activation, at mRNA and protein levels. Conversely, pharmacological inhibition of inflammasome activation abrogates HEV-provoked tRNAome remodeling, revealing a reciprocal interaction between the mature tRNAome and the NLRP3 inflammasome response. Remodeling the tRNAome results in improved decoding of codons directing leucine- and proline synthesis, which are the major amino acid constituents of IL-1β protein, whereas genetic or functional interference with tRNAome-mediated leucine decoding impairs inflammasome activation. Finally, we demonstrated that the mature tRNAome also actively responds to lipopolysaccharide (a key component of gram-negative bacteria)-triggered inflammasome activation, but the response dynamics and mode of actions are distinct from that induced by HEV infection. Our findings thus reveal the mature tRNAome as a previously unrecognized but essential mediator of host response to pathogens and represent a unique target for developing anti-inflammatory therapeutics.

Inflammatory cytokines and depression symptoms following hematopoietic cell transplantation

Increased synthesis and release of inflammatory signalling proteins is common among individuals with hematologic malignancies undergoing hematopoietic cell transplantation (HCT) due to intensive conditioning regimens and complications such as graft-versus-host-disease and infections. Prior research indicates that inflammatory responses can activate central nervous system pathways that evoke changes in mood. This study examined relationships between markers of inflammatory activity and depression symptoms following HCT. Individuals undergoing allogeneic (n = 84) and autologous (n = 155) HCT completed measures of depression symptoms pre-HCT and 1, 3, and 6 months post-HCT. Proinflammatory (IL-6, TNF-α) and regulatory (IL-10) cytokines were assessed by ELISA in peripheral blood plasma. Mixed-effects linear regression models indicated that patients with elevated IL-6 and IL-10 reported more severe depression symptoms at the post-HCT assessments. These findings were replicated when examining both allogeneic and autologous samples. Follow-up analyses clarified that relationships were strongest for neurovegetative, rather than cognitive or affective, symptoms of depression. These findings suggest that anti-inflammatory therapeutics targeting an inflammatory mediator of depression could improve quality of life of HCT recipients.

Apple-shaped obesity: A risky soil for cytokine-accelerated severity in COVID-19

Obesity has been recognized as one of the most significant risk factors for the deterioration and mortality associated with COVID-19, but the significance of obesity itself differs among ethnicity. Multifactored analysis of our single institute-based retrospective cohort revealed that high visceral adipose tissue (VAT) burden, but not other obesity-associated markers, was related to accelerated inflammatory responses and the mortality of Japanese COVID-19 patients. To elucidate the mechanisms how VAT-dominant obesity induces severe inflammation after severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2) infection, we infected two different strains of obese mice, C57BL/6JHamSlc-ob/ob (ob/ob), C57BLKS/J-db/db (db/db), genetically impaired in the leptin ligand and receptor, respectively, and control C57BL/6 mice with mouse-adapted SARS-CoV-2. Here, we revealed that VAT-dominant ob/ob mice were extremely more vulnerable to SARS-CoV-2 due to excessive inflammatory responses when compared to SAT-dominant db/db mice. In fact, SARS-CoV-2 genome and proteins were more abundant in the lungs of ob/ob mice, engulfed in macrophages, resulting in increased cytokine production including interleukin (IL)-6. Both an anti-IL-6 receptor antibody treatment and the prevention of obesity by leptin replenishment improved the survival of SARS-CoV-2-infected ob/ob mice by reducing the viral protein burden and excessive immune responses. Our results have proposed unique insights and clues on how obesity increases the risk of cytokine storm and death in patients with COVID-19. Moreover, earlier administration of antiinflammatory therapeutics including anti-IL-6R antibody to VAT-dominant patients might improve clinical outcome and stratification of the treatment for COVID-19, at least in Japanese patients.

Amniotic fluid derived extracellular vesicles as novel anti-inflammatory therapeutics against SARS-CoV-2 infection

Abstract The ongoing Covid-19 pandemic caused by SARS-CoV-2 is associated with acute respiratory distress syndrome (ARDS) and fatal pneumonia. Excessive inflammation caused by SARS-CoV-2 is the key driver of ARDS and lethal disease. Despite strong evidence for the role of virus induced inflammation in severe COVID19, no effective anti-inflammatory drug is available to control robust inflammation. Although corticosteroids are in clinical use to suppress excessive inflammation, global immunosuppressive effects of these drugs have limited their clinical success. Moreover, cytotoxicity caused by several chemically derived drugs is a cause of concern. Therefore, there is an urgent need to identify biologically derived immunomodulators that suppress inflammation without affecting antiviral immunity. In this study, we evaluated human amniotic fluid derived extracellular vesicles (hAF-EVs) as a potential safe biologic for immunomodulation during Covid-19. Our results showed that hAF-EVs significantly reduced inflammatory cytokine production in TLR2/4/7 and CoV structural protein stimulated mouse macrophages, in-vitro. Importantly, we also found that intraperitoneal administration of hAF-EVs in mice infected with a mouse-adapted SARS-CoV-2 reduced morbidity and mortality. A detailed examination of infected lungs showed that the increased protection in hAF-EV-treated mice was associated with reduced myeloid cell accumulation and inflammatory cytokine production. Collectively, we identify a novel biologic that has potential to suppress excessive inflammation and promote survival following SARS-CoV-2 infection, highlighting the translational potential of hAF-EVs against Covid-19 and other viral lung infections. This study was supported in part by institutional research funds from Oklahoma State University—Stillwater and NIGMS 5P20GM103648-10.

Single-Cell Sequencing Reveals the Optimal Time Window for Anti-Inflammatory Treatment in Spinal Cord Injury.

Though the occurrence of neuroinflammation after spinal cord injury (SCI) is essential for antigen clearance and tissue repair, excessive inflammation results in cell death and axon dieback. The effect of anti-inflammatory medicine used in clinical treatment remains debatable owing to the inappropriate therapeutic schedule that does not align with the biological process of immune reaction. A better understanding of the immunity process is critical to promote effective anti-inflammatory therapeutics. However, cellular heterogeneity, which results in complex cellular functions, is a major challenge. This study performs single-cell RNA sequencing by profiling the tissue proximity to the injury site at different time points after SCI. Depending on the analysis of single-cell data and histochemistry observation, an appropriate time window for anti-inflammatory medicine treatment is proposed. This work also verifies the mechanism of typical anti-inflammatory medicine methylprednisolone sodium succinate (MPSS), which is found attributable to the activation inhibition of cells with pro-inflammatory phenotype through the downregulation of pathways such as TNF, IL2, and MIF. These pathways can also be provided as targets for anti-inflammatory treatment. Collectively, this work provides a therapeutic schedule of 1-3 dpi (days post injury) to argue against classical early pulse therapy and provides some pathways for target therapy in the future.

Engineering a drug eluting ocular patch for delivery and sustained release of anti-inflammatory therapeutics.

Ocular inflammation is commonly associated with eye disease or injury. Effective and sustained ocular delivery of therapeutics remains a challenge due to the eye physiology and structural barriers. Herein, we engineered a photocrosslinkable adhesive patch (GelPatch) incorporated with micelles (MCs) loaded with Loteprednol etabonate (LE) for delivery and sustained release of drug. The engineered drug loaded adhesive hydrogel, with controlled physical properties, provided a matrix with high adhesion to the ocular surfaces. The incorporation of MCs within the GelPatch enabled solubilization of LE and its sustained release within 15 days. In vitro studies showed that MC loaded GelPatch supported cell viability and growth. In addition, subcutaneous implantation of the MC loaded GelPatch in rats confirmed its in vivo biocompatibility and stability within 28 days. This non-invasive, adhesive, and biocompatible drug eluting patch can be used as a matrix for the delivery and sustained release of hydrophobic drugs.

Retinoic Acid-Induced Regulation of Inflammatory Pathways Is a Potential Sepsis Treatment.

Sepsis is among the most dangerous known diseases, resulting from the dysregulation of the innate immune system in a process that is characterized largely by proinflammatory cytokines. It manifests as an excessive immune response to a pathogen and often leads to life-threatening complications such as shock and multiple-organ failure. Within the past several decades, much progress has been made to better understand the pathophysiology of sepsis and improve treatment. However, the average case-fatality rate for sepsis remains high. Current anti-inflammatory therapeutics for sepsis are not effective for use as first-line treatments. Focusing on all-trans-retinoic acid (RA), or activated vitamin A, as a novel anti-inflammatory agent, we have shown both in vitro and in vivo that RA decreases the production of proinflammatory cytokines. In vitro studies using mouse RAW 264.7 macrophages show that RA decreases tumor necrosis factor alpha (TNF-α) and interleukin-1β (IL-1β) and increases mitogen-activated protein kinase phosphatase 1 (MKP-1). RA treatment was also associated with the reduced phosphorylation of key inflammatory signaling proteins. Using a lipopolysaccharide and cecal slurry sepsis model, we found that RA significantly reduced mortality rates in mice, downregulated proinflammatory cytokine production, decreased neutrophil infiltration into lung tissue, and reduced the destructive lung histopathology typically seen in sepsis. We propose that RA may increase the function of native regulatory pathways and serve as a novel treatment for sepsis.

Regioselective metabolism of cannabinoids by cytochrome P450 2J2.

Cannabichromene (CBC) is a major non-psychoactive phytocannabinoid extracted from the cannabis plant. CBC has been shown to have anti-inflammatory effects; hence it can serve as a non-narcotic alternative to tetrahydrocannabinol (THC). Nevertheless, the metabolic pathways and metabolites of CBC have not been fully characterized. Metabolism of phytocannabinoids typically occurs via a superfamily of hemoproteins called cytochrome P450s (CYP450s). Our liquid chromatography-mass spectrometry (LC/MS) experiments show that CBC is metabolized to three different products by various human CYP450s. We identified that CYP450 2J2 (CYP2J2) predominantly produces 8'-hydroxy-CBC, an allylic hydroxide, out of the three metabolites. To investigate the CBC metabolic regioselectivity in CYP2J2, we leveraged atomistic molecular dynamics (MD) and modeling of the system. Using 200 unique conformations of CYP2J2 obtained from MD, we performed ensemble molecular docking of CBC to reveal three putative binding modes. We then assessed the stability of the obtained CBC binding modes by simulating them individually for 1 μs. Our simulations captured an average distance of 4.8 Å between the CYP2J2 heme and the 8’ carbon atom on CBC for one of the predominant binding modes, at which the allylic hydroxide metabolite occurs experimentally. At the regioselective binding mode, we observe conserved hydrogen bonding networks, mainly between the CBC hydroxyl group and the backbone oxygen of I487, as well as N379, stabilized by a water molecule. We further corroborated the stability of the regioselective binding modes by calculating relative binding free energies using alchemical free energy perturbation calculations. In conjunction, our computational and experimental methodologies elucidate a likely mode for regioselective binding and metabolism of CBC by CYP2J2, furthering the way towards accessible plant-based non-psychoactive anti-inflammatory therapeutics.

Lipoxin Mimetics and the Resolution of Inflammation.

Inflammation and its timely resolution are critical to ensure effective host defense and appropriate tissue repair after injury and or infection. Chronic, unresolved inflammation typifies many prevalent pathologies. The key mediators that initiate and drive the inflammatory response are well defined and targeted by conventional anti-inflammatory therapeutics. More recently, there is a growing appreciation that specific mediators, including arachidonate-derived lipoxins, are generated in self-limiting inflammatory responses to promote the resolution of inflammation and endogenous repair mechanisms without compromising host defense. We discuss the proresolving biological actions of lipoxins and recent efforts to harness their therapeutic potential through the development of novel, potent lipoxin mimetics generated via efficient, modular stereoselective synthetic pathways. We consider the evidence that lipoxin mimetics may have applications in limiting inflammation and reversing fibrosis and the underlying mechanisms.

Protein targeting by the itaconate family in immunity and inflammation.

Immune cells are metabolically plastic and respond to inflammatory stimuli with large shifts in metabolism. Itaconate is one of the most up-regulated metabolites in macrophages in response to the gram negative bacterial product LPS. As such, itaconate has recently been the subject of intense research interest. The artificial derivatives, including 4-Octyl Itaconate (4-OI) and Dimethyl Itaconate (DI) and naturally produced isomers, mesaconate and citraconate, have been tested in relation to itaconate biology with similarities and differences in the biochemistry and immunomodulatory properties of this family of compounds emerging. Both itaconate and 4-OI have been shown to modify cysteines on a range of target proteins, with the modification being linked to a functional change. Targets include KEAP1 (the NRF2 inhibitor), GAPDH, NLRP3, JAK1, and the lysosomal regulator, TFEB. 4-OI and DI are more electrophilic, and are therefore stronger NRF2 activators, and inhibit the production of Type I IFNs, while itaconate inhibits SDH and the dioxygenase, TET2. Additionally, both itaconate and derivates have been shown to be protective across a wide range of mouse models of inflammatory and infectious diseases, through both distinct and overlapping mechanisms. As such, continued research involving the comparison of itaconate and related molecules holds exciting prospects for the study of cysteine modification and pathways for immunomodulation and the potential for new anti-inflammatory therapeutics.

Investigating the Dynamic Binding Behavior of PMX53 Cooperating with Allosteric Antagonist NDT9513727 to C5a Anaphylatoxin Chemotactic Receptor 1 through Gaussian Accelerated Molecular Dynamics and Free-Energy Perturbation Simulations.

C5a anaphylatoxin chemotactic receptor 1 (C5aR1) is an important target in anti-inflammatory therapeutics. The cyclic peptide antagonist PMX53 binds to the orthosteric site located in the extracellular vestibule of C5aR1, and the non-peptide antagonist NDT9513727 binds to the allosteric site formed by the middle region of TM3 (trans-membrane helix), TM4, and TM5. We catch a sight of the variational binding mode of PMX53 during the Gaussian accelerated molecular dynamic (GaMD) simulations. In the binary complex of C5aR1 and PMX53, the PMX53 takes a dynamic binding mechanism during the simulation. Namely, the side chain of Arg6 of PMX53 extends to TM6-TM7 (pose 1) or swings to TM5 (pose 2), forming a salt bridge with Glu199. Meanwhile, in the ternary complex of C5aR1 with PMX53 and NDT9513727, the side chain of Arg6 of PMX53 swings to TM5 (pose 2) from extending to TM6-TM7 (pose 1) at the beginning of the GaMD simulation. In subsequent simulation, PMX53 stabilizes in the pose 2 binding mode by forming a stable salt bridge with Glu199. The free-energy perturbation (FEP) calculations demonstrate that pose 1 (ΔGbinding = -10.94 kcal/mol) is more stable in the binary complex and pose 2 (ΔGbinding = -7.91 kcal/mol) is unstable because of highly dynamic TM5. NDT9513727 interacts directly with TM4 and TM5 and stabilizes the hydrophobic stack between the extracellular sides of the two helices. Therefore, pose 2 (ΔGbinding = -16.27 kcal/mol) is notably stable than pose 1 (ΔGbinding = -9.78 kcal/mol) in the ternary complex. The identification of a novel binding mode of PMX53 and the detailed structural information of PMX53 interacting with a receptor obtained by GaMD simulations will be helpful in designing potent antagonists of C5aR1.

Pathophysiological mechanisms of thrombosis in acute and long COVID-19.

COVID-19 patients have a high incidence of thrombosis, and thromboembolic complications are associated with severe COVID-19 and high mortality. COVID-19 disease is associated with a hyper-inflammatory response (cytokine storm) mediated by the immune system. However, the role of the inflammatory response in thrombosis remains incompletely understood. In this review, we investigate the crosstalk between inflammation and thrombosis in the context of COVID-19, focusing on the contributions of inflammation to the pathogenesis of thrombosis, and propose combined use of anti-inflammatory and anticoagulant therapeutics. Under inflammatory conditions, the interactions between neutrophils and platelets, platelet activation, monocyte tissue factor expression, microparticle release, and phosphatidylserine (PS) externalization as well as complement activation are collectively involved in immune-thrombosis. Inflammation results in the activation and apoptosis of blood cells, leading to microparticle release and PS externalization on blood cells and microparticles, which significantly enhances the catalytic efficiency of the tenase and prothrombinase complexes, and promotes thrombin-mediated fibrin generation and local blood clot formation. Given the risk of thrombosis in the COVID-19, the importance of antithrombotic therapies has been generally recognized, but certain deficiencies and treatment gaps in remain. Antiplatelet drugs are not in combination with anticoagulant treatments, thus fail to dampen platelet procoagulant activity. Current treatments also do not propose an optimal time for anticoagulation. The efficacy of anticoagulant treatments depends on the time of therapy initiation. The best time for antithrombotic therapy is as early as possible after diagnosis, ideally in the early stage of the disease. We also elaborate on the possible mechanisms of long COVID thromboembolic complications, including persistent inflammation, endothelial injury and dysfunction, and coagulation abnormalities. The above-mentioned contents provide therapeutic strategies for COVID-19 patients and further improve patient outcomes.

Colonic innate immune defenses and microbiota alterations in acute swine dysentery

Brachyspira hyodysenteriae, an etiologic agent of swine dysentery (SD), is known for causing colitis. Although some aspects of colonic defenses during infection have been described previously, a more comprehensive picture of the host and microbiota interaction in clinically affected animals is required. This study aimed to characterize multiple aspects of colonic innate defenses and microbiome factors in B. hyodysenteriae-infected pigs that accompany clinical presentation of hemorrhagic diarrhea. We examined colonic mucus barrier modifications, leukocyte infiltration, cathelicidin expression, as well as microbiome composition. We showed that B. hyodysenteriae infection caused microscopic hemorrhagic colitis with abundant neutrophil infiltration in the colonic lamina propria and lumen, with minor macrophage infiltration. Mucus hypersecretion with abundant sialylated mucus in the colon, as well as mucosal colonization by [Acetivibrio] ethanolgignens, Lachnospiraceae, and Campylobacter were pathognomonic of B. hyodysenteriae infection. These findings demonstrate that B. hyodysenteriae produces clinical disease through multiple effects on host defenses, involving alterations of mucosal innate immunity and microbiota. Given that B. hyodysenteriae is increasingly resistant to antimicrobials, this understanding of SD pathogenesis may lead to future development of non-antibiotic and anti-inflammatory alternative therapeutics.

Neuroinflammation and Neurodegeneration of the Central Nervous System from Air Pollutants: A Scoping Review.

In this scoping review, we provide a selective mapping of the global literature on the effects of air pollution on the life-span development of the central nervous system. Our synthesis first defines developmental neurotoxicants and the model effects of particulate matter. We then discuss air pollution as a test bench for neurotoxicants, including animal models, the framework of systemic inflammation in all affected organs of the body, and the cascade effects on the developing brain, with the most prevalent neurological structural and functional outcomes. Specifically, we focus on evidence on magnetic resonance imaging and neurodegenerative diseases, and the links between neuronal apoptosis and inflammation. There is evidence of a developmental continuity of outcomes and effects that can be observed from utero to aging due to severe or significant exposure to neurotoxicants. These substances alter the normal trajectory of neurological aging in a propulsive way towards a significantly higher rate of acceleration than what is expected if our atmosphere were less polluted. The major aggravating role of this neurodegenerative process is linked with the complex action of neuroinflammation. However, most recent evidence learned from research on the effects of COVID-19 lockdowns around the world suggests that a short-term drastic improvement in the air we breathe is still possible. Moreover, the study of mitohormesis and vitagenes is an emerging area of research interest in anti-inflammatory and antidegenerative therapeutics, which may have enormous promise in combatting the deleterious effects of air pollution through pharmacological and dietary interventions.

Targeted delivery of platelet membrane modified extracellular vesicles into atherosclerotic plaque to regress atherosclerosis

Atherosclerosis is a major underlying cause of cardiovascular disease. Although certain success has been achieved in treatment for atherosclerosis, the risk of cardiovascular diseases still remains high. Anti-inflammation therapy was proved to halt atherosclerosis progression, but their clinical application was hindered by the systemic immunosuppressive effect. Since macrophages play a key role in the development of atherosclerosis, targeted delivery of anti-inflammatory therapeutics to lesional macrophages might be an effective therapeutic strategy to resolve localized inflammation while reducing the adverse effects. Mesenchymal stem cells derived extracellular vesicles (MSC-EVs) are believed to possess anti-atherosclerosis effects by reducing inflammation. In this study, we fabricated platelet mimetic MSC-EVs (P-EVs) by decorating EVs with platelets membranes. P-EVs inherited the natural homing ability of platelets to plaques and therapeutic effects of MSC-EVs. When injected into atherosclerotic mice, P-EVs were recruited to injured endothelium, then penetrated into plaques followed with endocytosis by inflammatory macrophages through the interaction between platelet membranes proteins and macrophages surface proteins. Subsequently, P-EVs delivered miRNAs into the cytoplasm of macrophages through lysosomal escape, which attenuated the progression of atherosclerosis eventually by switching the macrophage into anti-inflammatory phenotype, scavenging the overproduced ROS and reducing lipid deposition in lesional macrophages. In general, our study demonstrated the pro-resolving potential of P-EVs for targeted anti-inflammation therapy of atherosclerosis.

Swapping N-terminal regions among tick evasins reveals cooperative interactions influencing chemokine binding and selectivity

Class A tick evasins are natural chemokine-binding proteins that block the signaling of multiple chemokines from the CC subfamily through their cognate receptors, thus suppressing leukocyte recruitment and inflammation. Development of tick evasins as chemokine-targeted anti-inflammatory therapeutics requires an understanding of the factors controlling their chemokine recognition and selectivity. To investigate the role of the evasin N-terminal region for chemokine recognition, we prepared chimeric evasins by interchanging the N-terminal regions of four class A evasins, including a newly identified evasin, EVA-RPU02. We show through chemokine binding analysis of the parental and chimeric evasins that the N-terminal region is critical for chemokine binding affinity and selectivity. Notably, we found some chimeras were unable to bind certain cognate chemokine ligands of both parental evasins. Moreover, unlike any natural evasins characterized to date, some chimeras exhibited specific binding to a single chemokine. These results indicate that the evasin N terminus interacts cooperatively with the “body” of the evasin to enable optimum chemokine recognition. Furthermore, the altered chemokine selectivity of the chimeras validates the approach of engineering the N termini of evasins to yield unique chemokine recognition profiles.

Statin treatment dampens arterial wall inflammation assessed with 68GA-DOTATATE PET/CT

Background and Aims : At the core of atherosclerosis lies a process of chronic inflammation. With new anti-inflammatory therapeutics entering the field of research, accurate surrogate markers to evaluate their effectiveness in reducing cardiovascular events are paramount. 68Ga-DOTATATE has recently been proposed as a more specific marker of arterial wall inflammation than the metabolic marker 18F-fluorodeoxyglucose (18F-FDG). Here, we set out to investigate whether 68Ga-DOTATATE uptake is amenable to therapeutic intervention in patients with diabetes mellitus type 2 (DM2).

Nintedanib regulates intestinal smooth muscle hyperplasia and phenotype in vitro and in TNBS colitis in vivo

Chronic inflammation of the human intestine in Crohn’s disease (CD) causes bowel wall thickening, which typically progresses to stricturing and a recurrent need for surgery. Current therapies have limited success and CD remains idiopathic and incurable. Recent evidence shows a key role of intestinal smooth muscle cell (ISMC) hyperplasia in stricturing, which is not targeted by current anti-inflammatory therapeutics. However, progression of idiopathic pulmonary fibrosis, resembling CD in pathophysiology, is controlled by the tyrosine kinase inhibitors nintedanib (NIN) or pirfenidone, and we investigated these drugs for their effect on ISMC. In a culture model of rat ISMC, NIN inhibited serum- and PDGF-BB-stimulated growth and cell migration, and promoted the differentiated phenotype, while increasing secreted collagen. NIN did not affect signaling through PDGF-Rβ or NFκB but did inhibit cytokine-induced expression of the pro-inflammatory cytokines IL-1β and TNFα, supporting a transcriptional level of control. In TNBS-induced colitis in mice, which resembles CD, NIN decreased ISMC hyperplasia as well as expression of TNFα and IL-1β, without effect in control animals. NIN also inhibited growth of human ISMC in response to human serum or PDGF-BB, which further establishes a broad range of actions of NIN that support further trial in human IBD.