Topical azithromycin and clarithromycin inhibit acute and chronic skin inflammation in sensitized mice, with apparent selectivity for Th2-mediated processes in delayed-type hypersensitivity

Host immunomodulation strategies to combat pandemic-associated antimicrobial-resistant secondary bacterial infections

The incidence of secondary bacterial infections has increased in recent decades owing to various viral pandemics. These infections further increase the morbidity and mortality rates associated with viral infections and remain a significant challenge in clinical practice. Intensive antibiotic therapy has mitigated the threat of such infections; however, overuse and misuse of antibiotics have resulted in poor outcomes, such as inducing the emergence of bacterial populations with antimicrobial resistance (AMR) and reducing the therapeutic options for this crisis. Several antibiotic substitutes have been suggested and employed; however, they have certain limitations and novel alternatives are urgently required. This review highlights host immunomodulation as a promising strategy against secondary bacterial infections to overcome AMR. The definition and risk factors of secondary bacterial infections, features and limitations of currently available therapeutic strategies, host immune responses, and future perspectives for treating such infections are discussed.

In vivo modelling of cutaneous T-cell lymphoma: The role of SOCS1

Introduction

Mycosis fungoides (MF), the most common type of Cutaneous T cell Lymphoma (CTCL), is characterized by an inflamed skin intermixed with proliferating malignant mature skin-homing CD4+ T cells. Detailed genomic analyses of MF skin biopsies revealed several candidate genes possibly involved in genesis of these tumors and/or potential targets for therapy. These studies showed, in addition to common loss of cell cycle regulator CDKN2A, activation of several oncogenic pathways, most prominently and consistently involving JAK/STAT signaling. SOCS1, an endogenous inhibitor of the JAK/STAT signaling pathway, was identified as a recurrently deleted gene in MF, already occurring in the earliest stages of the disease.

Methods

To explore the mechanisms of MF, we create in vivo mouse models of autochthonous CTCLs and these genetically engineered mouse models (GEMMS) can also serve as valid experimental models for targeted therapy. We describe the impact of allelic deletion of Socs1 in CD4 T cells of the skin. To achieve this, we crossed inducible Cre-transgenic mice in the CD4 lineage with transgenic mice carrying floxed genes of Socs1. We first determined optimal conditions for Socs1 ablation with limited effects on circulating CD4 T-cells in blood. Next, we started time-course experiments mimicking sustained inflammation, typical in CTCL. FACS analysis of the blood was done every week. Skin biopsies were analyzed by immunocytochemical staining at the end of the experiment.

Results

We found that the Socs1 knockout transgenic group had thicker epidermis of treated skin compared with the control group and had more CD3 and CD4 in the skin of the transgenic group compared to the control group. We also noted more activation of Stat3 by staining for P-Stat3 in Socs1 knockout compared to wt CD4+T cells in the skin. The results also indicated that single copy loss of Socs1 in combination with sustained inflammation is insufficient to start a phenotype resembling early stage mycosis fungoides within eight weeks in these mice.

Conclusion

In sum, we developed and optimized an autochthonous murine model permitting selective knockout of Socs1 in skin infiltrating CD4 T-cells. This paves the way for more elaborate experiments to gain insight in the oncogenesis of CTCL.

Pleiotropic effects of antibiotics on T cell metabolism and T cell-mediated immunity

T cells orchestrate adaptive and innate immune responses against pathogens and transformed cells. However, T cells are also the main adaptive effector cells that mediate allergic and autoimmune reactions. Within the last few years, it has become abundantly clear that activation, differentiation, effector function, and environmental adaptation of T cells is closely linked to their energy metabolism. Beyond the provision of energy equivalents, metabolic pathways in T cells generate building blocks required for clonal expansion. Furthermore, metabolic intermediates directly serve as a source for epigenetic gene regulation by histone and DNA modification mechanisms. To date, several antibiotics were demonstrated to modulate the metabolism of T cells especially by altering mitochondrial function. Here, we set out to systematically review current evidence about how beta-lactam antibiotics, macrolides, fluoroquinolones, tetracyclines, oxazolidinones, nitroimidazoles, and amphenicols alter the metabolism and effector functions of CD4+ T helper cell populations and CD8+ T cells in vitro and in vivo. Based on this evidence, we have developed an overview on how the use of these antibiotics may be beneficial or detrimental in T cell-mediated physiological and pathogenic immune responses, such as allergic and autoimmune diseases, by altering the metabolism of different T cell populations.

Clarithromycin-treated chronic spontaneous urticaria with the negative regulation of FcεRΙ and MRGPRX2 activation via CD300f

Mast cells (MCs) are main effector cells in chronic spontaneous urticaria (CSU). Both Fc epsilon RI (FcεRΙ)- and MAS-related G coupled receptor-X2 (MRGPRX2)-mediated MC activations affect CSU course. Leukocyte mono-immunoglobulin-like receptor 3 (CD300f) has been shown to regulate FcεRΙ activation. However, no study has verified CD300f is a target to cure CSU. Therefore this study aimed to verify whether clarithromycin (CLA) regulates FcεRΙ- and MRGPRX2-mediated MC activations via CD300f and shows therapeutic effect on CSU. The target of CLA was verification. CLA inhibited FcεRΙ- and MRGPRX2-mediated MC activations were shown in vivo and in vitro. A single-center, self-comparison study was performed, and CLA-treated CSU was investigated in 28 patients who were not sensitive to the third-generation antihistamines. Serum inflammatory mediators in patients before and after CLA administration were analyzed. CLA effectively inhibited type Ι anaphylactic reactions and pseudo-allergic reactions in mice. Moreover, CLA inhibited FcεRΙ- and MRGPRX2-mediated MC signaling pathway activation. Regulatory effects of CLA were decreased significantly after CD300f knockdown. CLA effectively alleviated the symptoms of wheal and itch and reduced serum cytokine levels in patients. CLA negatively regulated FcεRΙ- and MRGPRX2-mediated MC activation via CD300f and showed significant therapeutic effect on CSU.

Long-term, low-dose macrolide antibiotic treatment in pediatric chronic airway diseases

Macrolide antibiotics are one of the most commonly used broad-spectrum antibiotics. They have an inhibitory effect on a variety of respiratory pathogens; besides, they have non-anti-infective effects, including anti-inflammatory, regulating airway secretion, immune regulation, and other effects. A growing number of studies have shown that the non-anti-infective effects of macrolides have important and potential value in the treatment of pediatric chronic airway diseases; the therapy was described as "long-term, low-dose usage"; unfortunately, there is no guideline or consensus that applies to children. To better carry out the mechanism and clinical research of non-anti-infective effect and promote its rational use in children, the authors summarize the evidence of the usage of long-term, low-dose macrolide antibiotic therapy (LLMAT) in the treatment of chronic airway diseases in children and the progress in recent years. IMPACT: This review summarizes the evidence (mostly in recent 5 years) of the usage of long-term, low-dose macrolide antibiotic therapy in the treatment of chronic airway diseases. The recent studies and guidelines support and enrich the point that long-term, low-dose macrolide antibiotic therapy has potential benefit for children with severe asthma, CF, non-CF bronchiectasis, and BO, which provides clinical references and is of clinical interest. Long-term, low-dose macrolide antibiotic therapy has good safety, and no serious events have been reported; however, potential cardiac side effects and macrolide resistance should be clinically noted.

Type 2 immunity plays an essential role for murine model of allergic contact dermatitis with mixed type 1/type 2 immune response

BACKGROUND

Both human and mouse allergic contact dermatitis (ACD) frequently demonstrates a combined type 1 and type 2 immune response. However, the relative importance of type 2 immunity in this setting has been incompletely understood yet.

OBJECTIVE

To explore an effector function of type 2 immunity in ACD with mixed type 1/type 2 immune response.

METHODS

Gene expression characteristics of contact hypersensitivity (CHS) model was examined by quantitative polymerase chain reaction. Cytokine profile of T cells was analyzed by flow cytometry. The involvement of type 2 immunity was assessed by antibody-mediated cytokine neutralization and cell depletion. The role of specific subset of cutaneous dendritic cells was evaluated using diphtheria toxin-induced cell-depleting mouse strains.

RESULTS

Oxazolone-induced CHS revealed a combination of type 1/type 2 gene expression. The severity of oxazolone-induced CHS was ameliorated by neutralization of IL-4 but not of IFN-γ, indicating that type 2 immunity plays a dominant effector function in this mixed type 1/type 2 model. Mechanistically, type 2 effector immunity was mounted by CD301b+Langeirn- dermal dendritic cells in part through thymic stromal lymphopoietin-interleukin 7 receptor alpha signaling-dependent manner.

CONCLUSION

Our findings suggest the clinical rationale for targeting type 2 immunity as a relevant therapeutic strategy for the mixed immune phenotype of ACD.

Nonantimicrobial Actions of Macrolides: Overview and Perspectives for Future Development

Macrolides are among the most widely prescribed broad spectrum antibacterials, particularly for respiratory infections. It is now recognized that these drugs, in particular azithromycin, also exert time-dependent immunomodulatory actions that contribute to their therapeutic benefit in both infectious and other chronic inflammatory diseases. Their increased chronic use in airway inflammation and, more recently, of azithromycin in COVID-19, however, has led to a rise in bacterial resistance. An additional crucial aspect of chronic airway inflammation, such as chronic obstructive pulmonary disease, as well as other inflammatory disorders, is the loss of epithelial barrier protection against pathogens and pollutants. In recent years, azithromycin has been shown with time to enhance the barrier properties of airway epithelial cells, an action that makes an important contribution to its therapeutic efficacy. In this article, we review the background and evidence for various immunomodulatory and time-dependent actions of macrolides on inflammatory processes and on the epithelium and highlight novel nonantibacterial macrolides that are being studied for immunomodulatory and barrier-strengthening properties to circumvent the risk of bacterial resistance that occurs with macrolide antibacterials. We also briefly review the clinical effects of macrolides in respiratory and other inflammatory diseases associated with epithelial injury and propose that the beneficial epithelial effects of nonantibacterial azithromycin derivatives in chronic inflammation, even given prophylactically, are likely to gain increasing attention in the future. SIGNIFICANCE STATEMENT: Based on its immunomodulatory properties and ability to enhance the protective role of the lung epithelium against pathogens, azithromycin has proven superior to other macrolides in treating chronic respiratory inflammation. A nonantibiotic azithromycin derivative is likely to offer prophylactic benefits against inflammation and epithelial damage of differing causes while preserving the use of macrolides as antibiotics.

Dieckol isolated from a brown alga, Eisenia nipponica, suppresses ear swelling from allergic inflammation in mouse

We previously found a lipophilic fraction of the methanol/chloroform extract of a brown alga, Eisenia nipponica, that had an antiallergic effect in a murine ear swelling test. In this study, we purified the active component from the lipophilic fraction using high performance liquid chromatography and analyzed the mass and nuclear magnetic resonance spectra. This uncovered the phlorotannin dieckol, which exhibited antiallergic effects in an ear swelling test using mice sensitized by arachidonic acid, 12-O-tetradecanoylphorbol-13-acetate, and oxazolone. Mechanistic investigations indicated that dieckol suppressed degranulation, chemical mediator release, and the expression of mRNA such as cyclooxygenase-2, interleukin-6, and tumor necrosis factor-α in rat basophilic leukemia-2H3 cells. In summary, we isolated dieckol from E. nipponica and demonstrated its antiallergic mechanisms. PRACTICAL APPLICATIONS: As the incidence of allergies increases worldwide, so too does the demand for food components with antiallergic and anti-inflammatory properties. Given this trend, we focused on a brown alga that displays a variety of bioactivities. Here, we have isolated dieckol from the antiallergic lipophilic fraction of E. nipponica and found that it possesses diverse physiological activities that may prevent lifestyle-related diseases. Consequently, dieckol or the alga containing this phlorotannin could be used as a health food ingredient to combat not only allergies, but also variety of disorders including the undesirable effects of aging.

The Effects of Antibiotics for Helicobacter pylori Eradication or Dapsone on Chronic Spontaneous Urticaria: A Systematic Review and Meta-Analysis

Background: Chronic spontaneous urticaria (CSU) is a disease with wheals and/or angioedema. Some drugs, especially antibiotics for Helicobacter pylori (H. pylori) eradication and the sulfone antibiotic dapsone, may be candidates for treating CSU. The present study assessed the efficacy of these antibiotic therapies for CSU. Methods: Databases (MEDLINE, the Cochrane Central Register of Controlled Trials, EMBASE, the World Health Organization International Clinical Trials Platform Search Portal and ClinicalTrials.gov) were searched until October 2020. Study selection, data abstraction and quality assessments were independently performed using the Grading of Recommendations Assessment, Development and Evaluation approach. The outcomes were the remission of CSU-related symptoms, activities and adverse events due to antibiotics for H. pylori eradication or dapsone. Results: Nine randomized controlled trials (RCTs; 361 patients) were included. The antibiotics for H. pylori eradication increased the remission rate (risk ratio (RR) = 3.99, 95% confidence interval (CI) = 1.31 to 12.14; I² = 0%), but dapsone did not (RR = 1.15, 95% CI = 0.74 to 1.78). Antibiotics for H. pylori eradication (standard mean difference (SMD) = 1.49, 95% CI = 0.80 to 2.18; I² = 69%) and dapsone (SMD = 7.00, 95% CI = 6.92 to 7.08; I² = 0%) improved symptoms. The evidence of certainty was moderate. Dapsone was associated with mild adverse events, whereas H. pylori eradication was not. Conclusion: Antibiotics, especially those for H. pylori eradication, improved the remission rate and symptoms of CSU with few adverse events. Further studies are needed.

Delayed Azithromycin Treatment Improves Recovery After Mouse Spinal Cord Injury

After spinal cord injury (SCI), macrophages infiltrate into the lesion and can adopt a wide spectrum of activation states. However, the pro-inflammatory, pathological macrophage activation state predominates and contributes to progressive neurodegeneration. Azithromycin (AZM), an FDA approved macrolide antibiotic, has been demonstrated to have immunomodulatory properties in a variety of inflammatory conditions. Indeed, we previously observed that post-SCI AZM treatment reduces pro-inflammatory macrophage activation. Further, a combined pre- and post-injury treatment paradigm improved functional recovery from SCI. Therefore, for the current study, we hypothesize that post-injury AZM treatment will improve recovery from SCI. To test this hypothesis, we examined the therapeutic potential of delayed AZM treatment on locomotor, sensory, and anatomical recovery. We administered AZM beginning 30-min, 3-h, or 24-h following contusion SCI in female mice, and then daily for 7 days. AZM administration beginning 30-min and 3-h post-injury improved locomotor recovery with increased stepping function relative to vehicle controls. Further, delaying treatment for 30-min after SCI significantly reduced lesion pathology. Initiating AZM treatment 24-h post-injury was not therapeutically effective. Regardless of the timing of the initial treatment, AZM did not statistically reduce the development of neuropathic pain (mechanical allodynia) nor increase neuron survival. Collectively, these results add to a growing body of evidence supporting AZM's translational potential as a therapeutic agent for SCI and other neuroinflammatory conditions in which patients currently have very few options.

Non-invasive bioluminescence imaging as a standardized assessment measure in mouse models of dermal inflammation

BACKGROUND

Myeloperoxidase is used as a marker and diagnostic tool for inflammatory processes. Hypochlorous acid produced by myeloperoxidase oxidizes luminol to produce light. By injecting luminol into experimental animals, inflammatory processes can be tracked in real-time by bioluminescence imaging (BLI).

OBJECTIVE

We aimed to establish BLI as a standardized assessment measure in three mouse models of dermal inflammation.

METHODS

Oxazolone-induced delayed-type-hypersensitivity (DTH) (acute), a model for dermatitis, imiquimod (IMQ) (sub-chronic) model for psoriasis and the (chronic) bleomycin model for scleroderma were used. In the first two models, dexamethasone and clobetasol, respectively, were used as reference compounds. In all cases, classical readouts such as dermal swelling, severity scores and histological analyses were compared with in- vivo bioluminescence.

RESULTS

In DTH, bioluminescence peaked earlier than ear swelling, reflecting early cell infiltration. Dexamethasone blocked both ear swelling and bioluminescence. In the IMQ model, bioluminescence closely reflected the psoriasis scores and histology and revealed a relapse-remitting course of the disease. Clobetasol partially decreased the disease severity. After stopping IMQ and clobetasol treatment, BLI adopted a rhythmic pattern during resolution. Bleomycin induced an increase in bioluminescence and in collagen thickness. BLI revealed a time-course of the effects of bleomycin that was not reflected by histology alone.

CONCLUSION

For drug discovery and translational purposes, it is important that disease processes be tracked in vivo and possibly over a long period. We conclude that BLI is a valuable and reliable method for in-vivo measurement of dermal inflammation and potentially for inflammation resolution.

The Immunomodulatory Effects of Macrolides-A Systematic Review of the Underlying Mechanisms

Background

The mechanisms underlying the non-antimicrobial immunomodulatory properties of macrolides are not well understood.

Objectives

To systematically review the evidence for the immunomodulatory properties of macrolides in humans and to describe the underlying mechanism and extent of their influence on the innate and adaptive immune system.

Methods

A systematic literature search was done in MEDLINE using the OVID interface from 1946 to December 2016 according to the preferred reporting items for systematic reviews and meta-analysis (PRISMA). Original articles investigating the influence of four macrolides (azithromycin, clarithromycin, erythromycin, and roxithromycin) on immunological markers in humans were included.

Results

We identified 22 randomized, controlled trials, 16 prospective cohort studies, and 8 case–control studies investigating 47 different immunological markers (186 measurements) in 1,834 participants. The most frequently reported outcomes were a decrease in the number of neutrophils, and the concentrations of neutrophil elastase, interleukin (IL)-8, IL-6, IL-1beta, tumor necrosis factor (TNF)-alpha, eosinophilic cationic protein, and matrix metalloproteinase 9. Inhibition of neutrophil function was reported more frequently than eosinophil function. A decrease in T helper (Th) 2 cells cytokines (IL-4, IL-5, IL-6) was reported more frequently than a decrease in Th1 cytokines (IL-2, INF-gamma).

Conclusion

Macrolides influence a broad range of immunological mechanisms resulting in immunomodulatory effects. To optimize the treatment of chronic inflammatory diseases by macrolides, further studies are necessary, particularly comparing different macrolides and dose effect relationships.

Azithromycin drives alternative macrophage activation and improves recovery and tissue sparing in contusion spinal cord injury

Background

Macrophages persist indefinitely at sites of spinal cord injury (SCI) and contribute to both pathological and reparative processes. While the alternative, anti-inflammatory (M2) phenotype is believed to promote cell protection, regeneration, and plasticity, pro-inflammatory (M1) macrophages persist after SCI and contribute to protracted cell and tissue loss. Thus, identifying non-invasive, clinically viable, pharmacological therapies for altering macrophage phenotype is a challenging, yet promising, approach for treating SCI. Azithromycin (AZM), a commonly used macrolide antibiotic, drives anti-inflammatory macrophage activation in rodent models of inflammation and in humans with cystic fibrosis.

Methods

We hypothesized that AZM treatment can alter the macrophage response to SCI and reduce progressive tissue pathology. To test this hypothesis, mice (C57BL/6J, 3-month-old) received daily doses of AZM (160 mg/kg) or vehicle treatment via oral gavage for 3 days prior and up to 7 days after a moderate-severe thoracic contusion SCI (75-kdyn force injury). Fluorescent-activated cell sorting was used in combination with real-time PCR (rtPCR) to evaluate the disposition and activation status of microglia, monocytes, and neutrophils, as well as macrophage phenotype in response to AZM treatment. An open-field locomotor rating scale (Basso Mouse Scale) and gridwalk task were used to determine the effects of AZM treatment on SCI recovery. Bone marrow-derived macrophages (BMDMs) were used to determine the effect of AZM treatment on macrophage phenotype in vitro.

Results

In accordance with our hypothesis, SCI mice exhibited significantly increased anti-inflammatory and decreased pro-inflammatory macrophage activation in response to AZM treatment. In addition, AZM treatment led to improved tissue sparing and recovery of gross and coordinated locomotor function. Furthermore, AZM treatment altered macrophage phenotype in vitro and lowered the neurotoxic potential of pro-inflammatory, M1 macrophages.

Conclusions

Taken together, these data suggest that pharmacologically intervening with AZM can alter SCI macrophage polarization toward a beneficial phenotype that, in turn, may potentially limit secondary injury processes. Given that pro-inflammatory macrophage activation is a hallmark of many neurological pathologies and that AZM is non-invasive and clinically viable, these data highlight a novel approach for treating SCI and other maladaptive neuroinflammatory conditions.

Electronic supplementary material

The online version of this article (doi:10.1186/s12974-015-0440-3) contains supplementary material, which is available to authorized users.

In Vivo Availability of Pro-Resolving Lipid Mediators in Oxazolone Induced Dermal Inflammation in the Mouse

The activation and infiltration of polymorphonuclear neutrophils (PMN) are critical key steps in inflammation. PMN-mediated inflammation is limited by anti-inflammatory and pro-resolving mechanisms, including specialized pro-resolving lipid mediators (SPM). We examined the effects of 15-epi-LXA4 on inflammation and the biosynthesis of pro-inflammatory mediators, such as prostaglandins, leukotriene B4 and various hydroxyeicosatetraenoic acids and SPM, in an oxazolone (OXA)-induced hypersensitivity model for dermal inflammation. 15-epi-LXA4 (100 μM, 5 μL subcutaneously injected) significantly (P < 0.05) reduced inflammation in skin, 24 hours after the OXA challenge, as compared to skin treated with vehicle. No significant influence on the biosynthesis of prostaglandins or leukotriene B4 was observed, whereas the level of 15S-hydroxy-eicosatetraenoic acid was significantly (P < 0.05) lower in the skin areas treated with 15-epi-LXA4. In spite of the use of a fully validated analytical procedure, no SPM were detected in the biological samples. To investigate the reason for the lack of analytical signal, we tried to mimic the production of SPM (lipoxins, resolvins, maresin and protectin) by injecting them subcutaneously into the skin of mice and studying the in vivo availability and distribution of the compounds. All analytes showed very little lateral distribution in skin tissue and their levels were markedly decreased (> 95%) 2 hours after injection. However, docosahexaenoic acid derivatives were biologically more stable than SPM derived from arachidonic acid or eicosapentaenoic acid.

Azithromycin: mechanisms of action and their relevance for clinical applications

Azithromycin is a macrolide antibiotic which inhibits bacterial protein synthesis, quorum-sensing and reduces the formation of biofilm. Accumulating effectively in cells, particularly phagocytes, it is delivered in high concentrations to sites of infection, as reflected in rapid plasma clearance and extensive tissue distribution. Azithromycin is indicated for respiratory, urogenital, dermal and other bacterial infections, and exerts immunomodulatory effects in chronic inflammatory disorders, including diffuse panbronchiolitis, post-transplant bronchiolitis and rosacea. Modulation of host responses facilitates its long-term therapeutic benefit in cystic fibrosis, non-cystic fibrosis bronchiectasis, exacerbations of chronic obstructive pulmonary disease (COPD) and non-eosinophilic asthma. Initial, stimulatory effects of azithromycin on immune and epithelial cells, involving interactions with phospholipids and Erk1/2, are followed by later modulation of transcription factors AP-1, NFκB, inflammatory cytokine and mucin release. Delayed inhibitory effects on cell function and high lysosomal accumulation accompany disruption of protein and intracellular lipid transport, regulation of surface receptor expression, of macrophage phenotype and autophagy. These later changes underlie many immunomodulatory effects of azithromycin, contributing to resolution of acute infections and reduction of exacerbations in chronic airway diseases. A sub-group of post-transplant bronchiolitis patients appears to be sensitive to azithromycin, as may be patients with severe sepsis. Other promising indications include chronic prostatitis and periodontitis, but weak activity in malaria is unlikely to prove crucial. Long-term administration of azithromycin must be balanced against the potential for increased bacterial resistance. Azithromycin has a very good record of safety, but recent reports indicate rare cases of cardiac torsades des pointes in patients at risk.

Cantharidin-induced inflammation in mouse ear model for translational research of novel anti-inflammatories

The murine model of cantharidin-induced ear inflammation was profiled in detail for its alignment with the human model and to explore the mechanism of anti-inflammatory activity of the macrolide antibiotics, clarithromycin and azithromycin. Ear swelling in CD1 mice persisted for 7 days, with peak intensity at 16 h after inflammation induction. As in humans, cantharidin (12.5 μg/ear) generated macrophage-inflammatory protein (MIP)-2, monocyte chemoattractant protein (MCP)-1, keratinocyte-derived chemokine (KC), interleukin (IL)-6, IL-1β, and myeloperoxidase (MPO) production, as well as neutrophil accumulation in mouse ear tissue. The tested macrolides, clarithromycin and azithromycin, administered orally (2 × 150 mg/kg) 0.5 h before and 5 h after cantharidin challenge, reduced MIP-2, MCP-1, KC, and MPO concentrations and thereby decreased ear swelling. Our results suggest that cantharidin-induced acute inflammation represents an excellent model for translational research of novel anti-inflammatories.