Role of macrophage migration inhibitory factor (MIF) in the skin

Bioengineered Silk Fibroin Hydrogel Reinforced with Collagen-Like Protein Chimeras for Improved Wound Healing

The study investigates the potentials of the rapid crosslinking hydrogel concoction comprising of natural silk fibroin (SF) and recombinant tailorable collagen-like protein with binding domains for wound repair. The formation of dityrosine crosslinks between the tyrosine moieties augments the formation of stable hydrogels, in the presence of the cytocompatible photo-initiator riboflavin and visible light. This uniquely engineered PASCH (Photo-activated silk fibroin and tailor-made collagen-like protein hydrogel) confers the key advantage of improved biological properties over the control hydrogels comprising only of SF. The physico-chemical characterization of the hydrogels with respect to crosslinking, modulus, and thermal stability delineates the ascendancy of PASCH 7:3 over other combinations. Furthermore, the hybrid protein hydrogel proves to be a favorable cellular matrix as it enhances cell adhesion, elongation, growth, and proliferation in vitro. Time-lapse microscopy studies reveal an enhanced wound closure in human endothelial cell monolayer (EA.hy926), while the gene expression studies portray the dynamic interplay of cytokines and growth factors in the wound milieu facilitating the repair and regeneration of cells, sculpted by the proteins. The results demonstrate the improved physical and biological properties of fabricated PASCH, depicting their synergism, and implying their competency for use in tissue engineering applications.

Analysis of the role of Dirofilaria repens macrophage migration inhibitory factors in host-parasite interactions

Introduction

Dirofilaria repens is a zoonotic parasitic filarial nematode that infects carnivores and occasionally humans. Knowledge of the host-parasite molecular interactions enabling the parasite's avoidance of the host immune response in subcutaneous dirofilariasis remains limited. Parasitic orthologues of host macrophage migration inhibitory factor (MIF) are molecules potentially involved in this process.

Material and Methods

Complementary DNA encoding two D. repens MIF orthologues (rDre-MIF-1 and rDre-MIF-2) was cloned into a pET-28a expression vector. The recombinant proteins were produced in Escherichia coli and purified using affinity nickel chromatography. The reactivity of both recombinant proteins was analysed with infected dog and immunised mouse sera.

Results

Stronger antibody production was induced by rDre-MIF-1 in mice, as evidenced by significantly higher levels of anti-rDre-MIF-1 total IgG, IgG2 and IgE antibodies than of anti-rDre-MIF-2 immunoglobulins. Additionally, a significantly different level of antibodies specific to both proteins was noted between the sera of infected dogs and those of uninfected dogs.

Conclusion

This study is the first attempt to characterise MIF orthologues from the filarial parasite D. repens, which may affect the immune response during infection.

The biological and therapeutic assessment of a P(3HB-co-4HB)-bioactive glass-graphene composite biomaterial for tissue regeneration

An ideal wound dressing should create a healing environment that relieves pain, protects against infections, maintains moisture, removes debris, and speeds up wound closure and repair. However, conventional options like gauze often fall short in fulfilling these requirements, especially for chronic or nonhealing wounds. Hence there is a critical need for inventive formulations that offer efficient, cost-effective, and eco-friendly alternatives. This study focuses on assessing the innovative formulation based on a microbial-derived copolymer known as poly(3-hydroxybutyrate-co-4-hydroxybutyrate), P(3HB-co-4HB) bioactive glass and graphene particles, and exploring their biological response in vitro and in vivo-to find the best combination that promotes cell adhesion and enhances wound healing. The formulation optimized at concentration of bioactive glass (1 w/w%) and graphene (0.01 w/w%) showed accelerated degradation and enhanced blood vessel formation. Meanwhile biocompatibility was evaluated using murine osteoblasts, human dermal fibroblasts, and standard cell culture assays, demonstrating no adverse effects after 7 days of culture and well-regulated inflammatory kinetics. Whole thickness skin defect using mice indicated the feasibility of the biocomposites for a faster wound closure and reduced inflammation. Overall, this biocomposite appears promising as an ideal wound dressing material and positively influencing wound healing rates.

Precision Dermatology: A Review of Molecular Biomarkers and Personalized Therapies

The evolution of personalized medicine in dermatology signifies a transformative shift towards individualized treatments, driven by the integration of biomarkers. These molecular indicators serve beyond diagnostics, offering insights into disease staging, prognosis, and therapeutic monitoring. Specific criteria guide biomarker selection, ensuring attributes like specificity, sensitivity, cost feasibility, stability, rapid detection, and reproducibility. This literature review, based on data from PubMed, SCOPUS, and Web of Science, explores biomarkers in Hidradenitis Suppurativa (HS), Psoriasis, Atopic Dermatitis (AD), Alopecia Areata (AA), Vitiligo, and Chronic Spontaneous Urticaria (CSU). In HS, TNF-α, IL-1β, and MMPs serve as biomarkers, influencing targeted therapies like adalimumab and anakinra. Psoriasis involves biomarkers such as TNF-α, IL-23, and HLA genes, shaping treatments like IL23 and IL17 inhibitors. AD biomarkers include ECP, IL-4, IL-13, guiding therapies like dupilumab and tralokinumab. For AA, lipocalin-2, cytokines, and genetic polymorphisms inform JAK inhibitors' use. Vitiligo biomarkers range from cytokines to genetic markers like TYR, TYRP1, guiding treatments like JAK inhibitors. CSU biomarkers encompass IgE, cytokines, and autologous serum tests, influencing therapies like omalizumab and cyclosporine. Comparing conditions, common proinflammatory markers reveal limited specificity. While some biomarkers aid diagnosis and standard treatments, others hold more scientific than clinical value. Precision medicine, driven by biomarkers, has shown success in skin malignancies. Future directions involve AI-powered algorithms, nanotechnology, and multi-omics integration for personalized dermatological care.

Association between macrophage migration inhibitory factor-173G/C polymorphism and psoriasis risk: A meta-analysis

Background The association between macrophage migration inhibitory factor (MIF)-173G/C polymorphism and psoriasis risk has been reported in several studies with inconsistent conclusions. Aims This study aims to obtain a more convincing estimate of the relationship between the MIF-173G/C polymorphism and psoriasis risk. Methods Web of Science, EMBASE, PubMed, Wan Fang Database and Chinese National Knowledge Infrastructure (CNKI) were searched up to September 2021 and eligible studies were collected. The pooled odds ratios with 95% confidence intervals were calculated to estimate the effects of MIF-173G/C polymorphism on psoriasis risk under different genetic models. All analyses were conducted using the STATA12.0 software. Results A total of 1101 psoriasis cases and 1320 healthy controls from 6 relevant studies were included in this meta-analysis. Pooled analysis suggested that MIF-173G/C polymorphism was associated with increased psoriasis risk under the allelic model (C vs. G: odds ratio = 1.30, 95% confidence interval = 1.04-1.63, P = 0.020), heterozygous model (GC vs. GG: odds ratio = 1.53, 95% confidence interval = 1.05-2.22, P = 0.027) and dominant model (CC + GC vs. GG: odds ratio = 1.51, 95% confidence interval = 1.05-2.18, P = 0.027). Limitation Very few studies on the MIF-173G/C polymorphism in psoriasis have been reported till now, thus the number of studies included in the present meta-analysis was relatively small. Due to the number of studies being relatively small and the lack of raw data, stratified analysis by ethnicity or type of psoriasis was not carried out. Conclusion This meta-analysis demonstrated that MIF-173G/C polymorphism might be related to psoriasis risk. Carriers of the C allele and the GC genotype might have higher odds to present with psoriasis.

Multidirectional activity of bakuchiol against cellular mechanisms of facial aging - Experimental evidence for a holistic treatment approach

Objective

Skin ageing is a multifactorial process involving formation of reactive oxygen species, consecutive inflammation with reduced epidermal and dermal cell viability and resulting damage to the extracellular matrix. Effective dermocosmetic treatment modalities should ideally address these hallmarks in a holistic approach. Here, we determined the corresponding activity profile of bakuchiol, a plant‐derived meroterpene, in an array of in vitro, ex vivo and in vivo studies and compared it to retinol, currently considered as gold standard in topical antiageing cosmetics.

Methods

The antioxidative capacity and power of bakuchiol and retinol were analysed by measuring 2,2′‐diphenyl‐1‐picrylhydrazyl (DPPH) reduction via its absorption decay and electron spin resonance spectroscopy, respectively. Effects on prostaglandin E2 (PGE2), macrophage migration inhibitory factor (MIF), fibroblast growth factor 7 (FGF7), collagen type I and VII (COL1A1, COL7A1), fibronectin (FN) levels as well as the metabolization of water‐soluble tetrazolium 1 (WST‐1) were determined in human dermal fibroblasts. Epidermal regeneration was assessed utilizing an in vitro wound healing model. FN protein levels were analysed ex vivo after treatment with a formulation containing bakuchiol, retinol or vehicle using suction blister fluid. Skin condition improvement was determined in vivo in a split‐face comparison study after application of bakuchiol or vehicle.

Results

In contrast to retinol, bakuchiol demonstrated high antioxidative efficacy. Levels of PGE2 and MIF were significantly decreased by both bakuchiol and retinol. Bakuchiol but not retinol significantly increased FGF7 protein levels. WST‐1 metabolization levels were significantly augmented by bakuchiol and retinol. Bakuchiol and retinol application led to a significant augmentation of COL1A1, COL7A1 and FN protein levels. Wounds supplemented with bakuchiol but not retinol displayed a significant increase in epidermis regeneration. Clinically, areas treated with a bakuchiol‐containing formulation showed a statistically significant increase in FN protein values after a 4‐week application compared to untreated areas and areas treated with vehicle.

Conclusion

These data provide evidence for the multidirectional efficacy of bakuchiol against cellular hallmarks of skin ageing. Its activity profile shares some common features with retinol but demonstrates several hitherto unknown biopositive effects in our studies, namely stimulation of the critical extracellular matrix component FN, and accelerated epidermal regeneration and wound healing.

Nematode Orthologs of Macrophage Migration Inhibitory Factor (MIF) as Modulators of the Host Immune Response and Potential Therapeutic Targets

One of the adaptations of nematodes, which allows long-term survival in the host, is the production of proteins with immunomodulatory properties. The parasites secrete numerous homologs of human immune mediators, such as macrophage migration inhibitory factor (MIF), which is a substantial regulator of the inflammatory immune response. Homologs of mammalian MIF have been recognized in many species of nematode parasites, but their role has not been fully understood. The application of molecular biology and genetic engineering methods, including the production of recombinant proteins, has enabled better characterization of their structure and properties. This review provides insight into the current state of knowledge on MIF homologs produced by nematodes, as well as their structure, enzymatic activity, tissue expression pattern, impact on the host immune system, and potential use in the treatment of parasitic, inflammatory, and autoimmune diseases.

Expression of macrophage migration inhibitory factor and its receptor CD74 in systemic sclerosis

Macrophage migration inhibitory factor (MIF) has been associated with the pathogenesis of several rheumatic diseases. In systemic sclerosis (SSc) it has been shown that MIF expression is dysregulated in serum and skin. However, the MIF receptor, CD74, has been poorly investigated and its potential role in the pathogenesis of SSc remains unknown. This study aimed to analyze mRNA, tissue, and serum expression of MIF and CD74 in patients with limited (lcSSc) and diffuse (dcSSc) systemic sclerosis. A case-control study in 20 SSc patients and 20 control subjects (CS) from southern México was conducted. MIF and CD74 mRNA expression levels were quantified by real-time PCR, MIF serum levels were measured by an ELISA kit, and MIF and its receptor CD74 were evaluated by immunohistochemistry of skin biopsies. MIF mRNA expression was significantly higher in CS than in SSc patients (p = 0.02), while CD74 showed no differences between patients and CS. MIF serum levels were similar between SSc patients and CS: dcSSc = 3.82 ng/ml, lcSSc = 3.57 ng/ml, and CS = 3.28 ng/ml. In skin biopsies of SSc, MIF and CD74 were enhanced in keratinocytes, while they showed decreased expression in endothelial cells. On the other hand, the staining of CD74 was high in fibroblasts of dcSSc patients. Our findings show MIF and CD74 deregulation at the transcriptional and translational levels in SSc, which might be associated with the proinflammatory process leading to tissue remodeling and excessive fibrosis in SSc.

The role of serum macrophage migration inhibitory factor in preoperative prediction of chronic rhinosinusitis with nasal polyps endotypes

BACKGROUND

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a highly heterogeneous disease and can be categorized into eosinophilic CRSwNP (eCRSwNP) and non-eosinophilic CRSwNP (neCRSwNP). Exploring effective biomarkers to distinguish endotypes is important for personalized therapies. The present study aims to evaluate the predictive value of serum MIF in CRSwNP endotypes.

METHODS

One hundred and twenty CRSwNP patients, including 51 eCRSwNP and 69 neCRSwNP, 40 chronic rhinosinusitis without nasal polyps (CRSsNP) patients and 40 healthy controls (HC) were enrolled. Serum MIF levels were determined by enzyme-linked immunosorbent assay (ELISA). The patients' clinical variables were analyzed for correlations with serum MIF. Receiver operating characteristic (ROC) curve and multivariate analysis were utilized to assess the predictive value of serum MIF in CRSwNP endotypes.

RESULTS

The serum MIF levels were significantly higher in CRSwNP group than CRSsNP group and HC group (P < 0.001), and the serum MIF levels were increased in eCRSwNP compared to neCRSwNP group (P = 0.006). Elevated serum MIF levels were significantly correlated with blood eosinophil (B-EOS) count (r = 0.411, P < 0.001), B-EOS percentage (r = 0.377, P < 0.001), visual analog scale score (r = 0.204, P = 0.025), tissue eosinophil (T-EOS) count (r = 0.705, P < 0.001) and T-EOS percentage (r = 0.671, P < 0.001) in CRSwNP patients. ROC curve demonstrated that serum MIF exhibited good preoperative prediction in CRSwNP endotypes (area under the curve = 0.925, P < 0.001). Multivariate regression analysis showed that serum MIF was an independent factor associated with CRSwNP endotypes.

CONCLUSIONS

This was the first study identifying serum MIF as a possible specific biomarker for preoperatively distinguishing CRSwNP endotypes. Furthermore, the serum MIF levels were found to be closely associated with the degree of mucosal eosinophil infiltration.

The Effects of Human Bone Marrow-Derived Mesenchymal Stem Cell Conditioned Media Produced with Fetal Bovine Serum or Human Platelet Lysate on Skin Rejuvenation Characteristics

Background and Objectives

Human mesenchymal stem cell-conditioned medium (MSC-CM) is produced using mesenchymal stem cell culture technology and has various benefits for the skin, including wrinkle removal, skin regeneration, and increased antioxidant activity. Its popularity is thus increasing in the field of functional cosmetics.

Methods and Results

In this study, we analyzed the effects of fetal bovine serum-supplemented MSC-CM (FBS- MSC-CM) and human platelet lysate-supplemented MSC-CM (hPL-MSC-CM) on skin rejuvenation characteristics. We found that the concentrations of important growth factors (VEGF, TGF-β1, and HGF) and secretory proteins for skin regeneration were significantly higher in hPL-MSC-CM than in FBS-MSC-CM. Furthermore, the capacity for inducing proliferation of human dermal fibroblast (HDF) and keratinocytes, the migration ability of HDF, extracellular matrix (ECM) production such as collagen and elastin was higher in hPL-MSC-CM than that in FBS- MSC-CM.

Conclusions

These results support the usefulness and high economic value of hPL-MSC-CM as an alternative source of FBS-MSC-CM in the cosmetic industry for skin rejuvenation.

Berberine induces anti-atopic dermatitis effects through the downregulation of cutaneous EIF3F and MALT1 in NC/Nga mice with atopy-like dermatitis

Atopic dermatitis (AD) is a chronic inflammatory skin disease with severe pruritus. Berberine, a naturally occurring isoquinoline alkaloid, has anti-inflammatory effects. This study investigated the effects and molecular mechanisms of berberine on AD-like symptoms in mice. In this study, NC/Nga mice with atopy-like dermatitis (dermatitis mice), fibroblast and mast cells were used. In dermatitis mice, intermittent oral administrations of berberine 3 times a week for 12 days inhibited skin symptom, itching, cutaneous infiltration of eosinophils and mast cells, and the expression of cutaneous eotaxin, macrophage migration inhibitory factor (MIF) and IL-4. Berberine also attenuated IL-4/MIF-induced eotaxin in fibroblasts and allergen-induced MIF and IL-4 in mast cells. In mast cells, the GeneChip® microarray showed that antigen increased the expression of EIF3F and MALT1, inhibited by berberine. The siRNAs for them inhibited the expression of MIF and IL-4 in antigen-stimulated mast cells. These results suggest that berberine improves AD-like symptoms through the inhibition of the eotaxin and pro-inflammatory cytokine expression and the related inflammatory cell recruitment. It is also suggested that the downregulation of EIF3F and MALT1 by berberine is involved in suppressing the cytokine expression. Taken together, berberine or berberine-containing crude drugs are expected to contribute to the improvement of AD symptoms.

Dermal fibroblasts cultured from donors with type 2 diabetes mellitus retain an epigenetic memory associated with poor wound healing responses

The prevalence of Type 2 diabetes mellitus (T2DM) is escalating globally. Patients suffer from multiple complications including the development of chronic wounds that can lead to amputation. These wounds are characterised by an inflammatory environment including elevated tumour necrosis factor alpha (TNF-α). Dermal fibroblasts (DF) are critical for effective wound healing, so we sought to establish whether there were any differences in DF cultured from T2DM donors or those without diabetes (ND-DF). ND- and T2DM-DF when cultured similarly in vitro secreted comparable concentrations of TNF-α. Functionally, pre-treatment with TNF-α reduced the proliferation of ND-DF and transiently altered ND-DF morphology; however, T2DM-DF were resistant to these TNF-α induced changes. In contrast, TNF-α inhibited ND- and T2DM-DF migration and matrix metalloprotease expression to the same degree, although T2DM-DF expressed significantly higher levels of tissue inhibitor of metalloproteases (TIMP)-2. Finally, TNF-α significantly increased the secretion of pro-inflammatory cytokines (including CCL2, CXCL1 and SERPINE1) in ND-DF, whilst this effect in T2DM-DF was blunted, presumably due to the tendency to higher baseline pro-inflammatory cytokine expression observed in this cell type. Collectively, these data demonstrate that T2DM-DF exhibit a selective loss of responsiveness to TNF-α, particularly regarding proliferative and secretory functions. This highlights important phenotypic changes in T2DM-DF that may explain the susceptibility to chronic wounds in these patients.

The Role of MIF on Eosinophil Biology and Eosinophilic Inflammation

Macrophage migration inhibitory factor (MIF) is an inflammatory cytokine that participates in innate and adaptive immune responses. MIF contributes to the resistance against infection agents, but also to the cellular and tissue damage in infectious, autoimmune, and allergic diseases. In the past years, several studies demonstrated a critical role for MIF in the pathogenesis of type-2-mediated inflammation, including allergy and helminth infection. Atopic patients have increased MIF amounts in affected tissues, mainly produced by immune cells such as macrophages, Th2 cells, and eosinophils. Increased MIF mRNA and protein are found in activated Th2 cells, while eosinophils stock pre-formed MIF protein and secrete high amounts of MIF upon stimulation. In mouse models of allergic asthma, the lack of MIF causes an almost complete abrogation of the cardinal signs of the disease including mucus secretion, eosinophilic inflammation, and airway hyper-responsiveness. Additionally, blocking the expression of MIF in animal models leads to significant reduction of pathological signs of eosinophilic inflammation such as rhinitis, atopic dermatitis, eosinophilic esophagitis and helminth infection. A number of studies indicate that MIF is important in the effector phase of type-2 immune responses, while its contribution to Th2 differentiation and IgE production is not consensual. MIF has been found to intervene in different aspects of eosinophil physiology including differentiation, survival, activation, and migration. CD4+ T cells and eosinophils express CD74 and CXCR4, receptors able to signal upon MIF binding. Blockage of these receptors with neutralizing antibodies or small molecule antagonists also succeeds in reducing the signals of inflammation in experimental allergic models. Together, these studies demonstrate an important contribution of MIF on eosinophil biology and in the pathogenesis of allergic diseases and helminth infection.

Soluble CD27 and MIF as possible serum biomarkers of vitiligo activity in Egyptian patients in Sharkia Governorate

Contrary to other inflammatory skin disorders like psoriasis or atopic dermatitis, vitiligo does not present with distinct inflammatory symptoms that can be easily evaluated by clinical examination. Identification of a putative biomarker to inform early and accurate treatment responses could be of considerable value. This study aims to validate levels of serum soluble CD27 (sCD27) and macrophage Migration Inhibitory Factor (MIF) as biomarkers of vitiligo to improve the quality of disease management. This cross-sectional study was conducted on 32 vitiligo patients, stratified into two subgroups of 22 active and 10 stable vitiligo patients; the stable group containing 1 segmental and 9 nonsegmental presentations, and 32 matched healthy individuals as the control group. Of the 32 patients in the study, 21 were female and 11 were male with a median age of 30 years. The measurements of the study parameters of sCD27 and MIF in the serum were carried out through blood sampling and followed up for three months at onemonth intervals for stable vitiligo cases. Mean serum levels of sCD27 and MIF were significantly higher in vitiligo patients than in the control group. A positive correlation was observed in active vitiligo cases between both serum MIF and sCD27 levels and the spreading item of Vitiligo European Task Force (VETF) score as an indicator of disease activity. Serum sCD27 and MIF levels in vitiligo patients were observed to be higher than that of controls with greater correlation found for sCD27 with disease activity.

The regulation of protein kinase casein kinase II by apigenin is involved in the inhibition of ultraviolet B-induced macrophage migration inhibitory factor-mediated hyperpigmentation

Ultraviolet (UV) radiation elicits melanogenesis and pigmentation in the skin. Apigenin (4',5,7-trihydroxyflavone [AGN]) is a plant flavone contained in various herbs, fruits, and vegetables. We herein investigated antimelanogenic properties of AGN and the molecular mechanisms of the action of AGN. In UVB-treated mice, AGN inhibited cutaneous hyperpigmentation and macrophage migration inhibitory factor (MIF) expression as a melanogenesis-related key factor. In mouse keratinocytes, AGN inhibited the expression of MIF and also the related factors (e.g., stem cell factor and proteinase-activated receptor 2) induced by MIF. In addition to ellagic acid as a casein kinase II (CK2) inhibitor, AGN suppressed CK2 enzymatic activity and UVB-induced CK2 expression and subsequent phosphorylation of IκB and MIF expression. These results suggest that AGN inhibits UVB-induced hyperpigmentation through the regulation of CK2-mediated MIF expression in keratinocytes.

Topical estradiol increases epidermal thickness and dermal collagen of foreskin prior to hypospadia surgery - Randomized double blinded controlled trial

INTRODUCTION

The use of preoperative topical testosterone stimulation prior to hypospadias correction aims to increase penile size and achieve better surgical results. Topical estradiol has been shown to improve the quality of skin in other sites, but its use in boys with hypospadia has not yet been elucidated.

OBJECTIVE

This study aims to evaluate the primary effects in epidermal thickness and collagen distribution of estradiol compared to testosterone and placebo in skin of prepuce before hypospadia surgery.

MATHERIALS AND METHODS

Patients were randomized into three groups according to the topical hormone used: TG: Testosterone ointment; EG: Estradiol ointment; CG: Neutral base ointment. Fragments of foreskin were excised, fixed and then sectioned for histology. For each sample, epidermal thickness and dermal collagen expression was measured by specific computer analysis, P-values of <0.05.

RESULTS

Thirty-three patients with a mean age of 4.01 ± 2.92 years were included. Hypospadia classification was similar in all three groups. Mean epidermal thickness and collagen type I expression in EG were greater than those of the other groups. Collagen type III expression was similar in all groups.

DISCUSSION

Foreskin has a fundamental role in many techniques of hypospadias surgery and can be used either as a graft or a flap in the correction of the penile defect. Increase of epidermal thickness and dermal collagen observed in the present study has already been related to use of estradiol in other skin sites, but not yet in foreskin. Further studies are needed to evaluate the real significance of these findings in boys with hypospadias.

CONCLUSION

Use of topical estradiol before hypospadias surgery lead to greater epidermal thickness and increases dermal collagen expression in foreskin.

In-depth serum proteomics reveals biomarkers of psoriasis severity and response to traditional Chinese medicine

Serum and plasma contain abundant biological information that reflect the body's physiological and pathological conditions and are therefore a valuable sample type for disease biomarkers. However, comprehensive profiling of the serological proteome is challenging due to the wide range of protein concentrations in serum. Methods: To address this challenge, we developed a novel in-depth serum proteomics platform capable of analyzing the serum proteome across ~10 orders or magnitude by combining data obtained from Data Independent Acquisition Mass Spectrometry (DIA-MS) and customizable antibody microarrays. Results: Using psoriasis as a proof-of-concept disease model, we screened 50 serum proteomes from healthy controls and psoriasis patients before and after treatment with traditional Chinese medicine (YinXieLing) on our in-depth serum proteomics platform. We identified 106 differentially-expressed proteins in psoriasis patients involved in psoriasis-relevant biological processes, such as blood coagulation, inflammation, apoptosis and angiogenesis signaling pathways. In addition, unbiased clustering and principle component analysis revealed 58 proteins discriminating healthy volunteers from psoriasis patients and 12 proteins distinguishing responders from non-responders to YinXieLing. To further demonstrate the clinical utility of our platform, we performed correlation analyses between serum proteomes and psoriasis activity and found a positive association between the psoriasis area and severity index (PASI) score with three serum proteins (PI3, CCL22, IL-12B). Conclusion: Taken together, these results demonstrate the clinical utility of our in-depth serum proteomics platform to identify specific diagnostic and predictive biomarkers of psoriasis and other immune-mediated diseases.

Macrophage migration inhibitory factor as an incriminating agent in vitiligo

BACKGROUND

Vitiligo is an autoimmune skin disorder in which the loss of melanocytes is mainly attributed to defective autoimmune mechanisms and, lately, there has been more emphasis on autoinflammatory mediators. Among these is the macrophage migration inhibitory factor, which is involved in many autoimmune skin diseases. However, little is known about the contribution of this factor to vitiligo vulgaris.

OBJECTIVE

To determine the hypothesized role of migration inhibitory factor in vitiligo via estimation of serum migration inhibitory factor levels and migration inhibitory factor mRNA concentrations in patients with vitiligo compared with healthy controls. We also aimed to assess whether there is a relationship between the values of serum migration inhibitory factor and/or migration inhibitory factor mRNA with disease duration, clinical type and severity in vitiligo patients.

METHODS

Evaluation of migration inhibitory factor serum level and migration inhibitory factor mRNA expression by ELISA and real-time PCR, respectively, were performed for 50 patients with different degrees of vitiligo severity and compared to 15 age- and gender-matched healthy volunteers as controls.

RESULTS

There was a highly significant increase in serum migration inhibitory factor and migration inhibitory factor mRNA levels in vitiligo cases when compared to controls (p<0.001). There was a significant positive correlation between both serum migration inhibitory factor and migration inhibitory factor mRNA concentrations in vitiligo patients, and each of them with duration and severity of vitiligo. In addition, patients with generalized vitiligo have significantly elevated serum migration inhibitory factor and mRNA levels than control subjects.

STUDY LIMITATIONS

Small number of investigated subjects.

CONCLUSIONS

Migration inhibitory factor may have an active role in the development of vitiligo, and it may also be a useful index of disease severity. Consequently, migration inhibitory factor may be a new treatment target for vitiligo patients.

The Fate of a Hapten - From the Skin to Modification of Macrophage Migration Inhibitory Factor (MIF) in Lymph Nodes

Skin (contact) allergy, the most prevalent form of immunotoxicity in humans, is caused by low molecular weight chemicals (haptens) that penetrate stratum corneum and modify endogenous proteins. The fate of haptens after cutaneous absorption, especially what protein(s) they react with, is largely unknown. In this study the fluorescent hapten tetramethylrhodamine isothiocyanate (TRITC) was used to identify hapten-protein conjugates in the local lymph nodes after topical application, as they play a key role in activation of the adaptive immune system. TRITC interacted with dendritic cells but also with T and B cells in the lymph nodes as shown by flow cytometry. Identification of the most abundant TRITC-modified protein in lymph nodes by tandem mass spectrometry revealed TRITC-modification of the N-terminal proline of macrophage migration inhibitory factor (MIF) – an evolutionary well-conserved protein involved in cell-mediated immunity and inflammation. This is the first time a hapten-modified protein has been identified in lymph nodes after topical administration of the hapten. Most haptens are electrophiles and can therefore modify the N-terminal proline of MIF, which has an unusually reactive amino group under physiological conditions; thus, modification of MIF by haptens may have an immunomodulating role in contact allergy as well as in other immunotoxicity reactions.

Macrophage migration inhibitory factor (MIF) promotes rat airway muscle cell proliferation and migration mediated by ERK1/2 and FAK signaling

Macrophage migration inhibitory factor (MIF) is an inflammatory mediator that contributes to asthmatic airway remodeling; however, little is known regarding the effects of MIF on airway smooth muscle cells (ASMCs). In the present study, we found that an enhanced expression of MIF promoted ASMC proliferation, increased the population of cells in the S/G2 phase, downregulated P21 expression, and upregulated cyclin D1, cyclin D3, and Cdk6 expression. In addition, the apoptosis of ASMCs was significantly decreased in response to MIF overexpression, compared with the negative control. Moreover, MIF facilitated the migration of ASMCs by upregulating the expression of matrix metalloproteinase (MMP)-2. Finally, we showed that MIF increased the phosphorylation of extracellular regulated protein kinases (ERK) 1/2 and focal adhesion kinase (FAK), which are associated with proliferation and migration. In conclusion, this study demonstrated that MIF overexpression promotes the proliferation and migration of ASMCs by upregulating the activity of the ERK1/2 and FAK signaling pathways in these cells, further indicating that inhibition of MIF may prove to be an effective strategy for treating asthma patients with airway remodeling.

Macrophage Migration Inhibitory Factor as an Emerging Drug Target to Regulate Antioxidant Response Element System

Oxidative stress is involved in pathophysiology and pathological conditions of numerous human diseases. Thus, understanding the mechanisms underlying the redox homeostasis in cells and organs is valuable for discovery of therapeutic drugs for oxidative stress-related diseases. Recently, by applying chemical biology approach with an ARE activator, BTZO-1, we found macrophage migration inhibitory factor (MIF) as a new regulator of antioxidant response element- (ARE-) mediated gene transcription. BTZO-1 and its active derivatives bound to MIF and protected cells and organs from oxidative insults via ARE activation in animal models with oxidative stress such as ischemia/reperfusion injury, inflammatory bowel diseases, and septic shock. In this review, we briefly highlight key findings in understanding the MIF-ARE system.

Macrophage migration inhibitory factor protects from nonmelanoma epidermal tumors by regulating the number of antigen-presenting cells in skin

The response of the skin to harmful environmental agents is shaped decisively by the status of the immune system. Keratinocytes constitutively express and secrete the chemokine-like mediator, macrophage migration inhibitory factor (MIF), more strongly than dermal fibroblasts, thereby creating a MIF gradient in skin. By using global and epidermis-restricted Mif-knockout (Mif^-/- and K14-Cre^+/tg; Mif^fl/fl) mice, we found that MIF both recruits and maintains antigen-presenting cells in the dermis/epidermis. The reduced presence of antigen-presenting cells in the absence of MIF was associated with accelerated and increased formation of nonmelanoma skin tumors during chemical carcinogenesis. Our results demonstrate that MIF is essential for maintaining innate immunity in skin. Loss of keratinocyte-derived MIF leads to a loss of control of epithelial skin tumor formation in chemical skin carcinogenesis, which highlights an unexpected tumor-suppressive activity of MIF in murine skin.-Brocks, T., Fedorchenko, O., Schliermann, N., Stein, A., Moll, U. M., Seegobin, S., Dewor, M., Hallek, M., Marquardt, Y., Fietkau, K., Heise, R., Huth, S., Pfister, H., Bernhagen, J., Bucala, R., Baron, J. M., Fingerle-Rowson, G. Macrophage migration inhibitory factor protects from nonmelanoma epidermal tumors by regulating the number of antigen-presenting cells in skin.

Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis Associated with Acetaminophen Use during Viral Infections

An association between drug treatment for viral infections and severe cutaneous adverse reactions has been noted. We investigated six patients diagnosed with Stevens–Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) after being prescribed acetaminophen for suspected viral illnesses. Multiplex analysis was performed to measure cytokine levels in sera before and after treatment. IL-2Rα levels significantly decreased during the convalescence phase. Although acetaminophen is relatively safe, the drug can trigger SJS/TEN in patients with suspected viral infections. T-cells and monocytes may be key components of the link between viral infection and acetaminophen-induced SJS/TEN.

Macrophage migration inhibitory factor: a potential therapeutic target for rheumatoid arthritis

Macrophage migration inhibitory factor (MIF) is originally identified in the culture medium of activated T lymphocytes as a soluble factor that inhibits the random migration of macrophages. MIF is now recognized as a multipotent cytokine involved in the regulation of immune and inf lammatory responses. In rheumatoid arthritis (RA), MIF promotes inf lammatory responses by inducing proinflammatory cytokines and tissue-degrading molecules, promoting the proliferation and survival of synovial fibroblasts, stimulating neutrophil chemotaxis, and regulating angiogenesis and osteoclast differentiation. Expression of MIF in synovial tissue and synovial fluid levels of MIF are elevated in RA patients. Specifically, MIF levels correlate with RA disease activity and high levels are associated with bone erosion. In animal models of RA, the genetic and therapeutic inhibition of MIF has been shown to control inflammation and bone destruction. Based on the role of MIF in RA pathogenesis, small molecular inhibitors targeting it or its receptor pathways could provide a new therapeutic option for RA patients.

Macrophage migration inhibitory factor promotes eosinophil accumulation and tissue remodeling in eosinophilic esophagitis

Macrophage migration inhibitory factor (MIF) is involved in eosinophil biology and in type 2 inflammation, contributing to allergic and helminthic diseases. We hypothesized that MIF participates in the pathogenesis of eosinophilic esophagitis (EoE), an allergic condition characterized by esophageal eosinophilic inflammation. MIF is highly expressed in esophageal mucosa of patients with EoE, compared with gastro-esophageal reflux disease and control patients, where it co-localizes predominantly with eosinophils. In vitro, recombinant MIF promotes human eosinophil chemotaxis, while MIF antagonist and CXCR4 antagonist, AMD3100, revert this effect. In a model of EoE induced by ovalbumin, Mif-deficient mice have reduced inflammation and collagen deposition compared with wild-type (WT) mice. Importantly, treatment of WT mice with anti-MIF or with AMD3100 during the challenge phase prevents accumulation of eosinophils and tissue remodeling. Conversely, recombinant MIF promoted tissue eosinophil inflammation in allergic mice. Together, these results implicate MIF in the pathogenesis of esophageal inflammation and suggest that targeting MIF might represent a novel therapy for EoE.

Role of macrophage migration inhibitory factor (MIF) in pollen-induced allergic conjunctivitis and pollen dermatitis in mice

Pollen is a clinically important airborne allergen and one of the major causes of allergic conjunctivitis. A subpopulation of patients with atopic dermatitis (AD) are also known to have exacerbated skin eruptions on the face, especially around the eyelids, after contact with pollen. This pollen-induced skin reaction is now known as pollen dermatitis. Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine that plays an essential role in allergic inflammation. Recent findings suggest that MIF is involved in several allergic disorders, including AD. In this study, MIF knockout (KO), MIF transgenic (Tg) and WT littermate mice were immunized with ragweed (RW) pollen or Japanese cedar (JC) pollen and challenged via eye drops. We observed that the numbers of conjunctiva- and eyelid-infiltrating eosinophils were significantly increased in RW and JC pollen-sensitized MIF Tg compared with WT mice or MIF KO mice. The mRNA expression levels of eotaxin, interleukin (IL)-5 and IL-13 were increased in pollen-sensitized eyelid skin sites of MIF Tg mice. An in vitro analysis revealed that high eotaxin expression was induced in dermal fibroblasts by MIF combined with stimulation of IL-4 or IL-13. This eotaxin expression was inhibited by the treatment with CD74 siRNA in fibroblasts. These findings indicate that MIF can induce eosinophil accumulation in the conjunctiva and eyelid dermis exposed to pollen. Therefore, targeted inhibition of MIF might result as a new option to control pollen-induced allergic conjunctivitis and pollen dermatitis.

Macrophage migration inhibitory factor triggers chemotaxis of CD74+CXCR2+ NKT cells in chemically induced IFN-γ-mediated skin inflammation

IFN-γ mediates chemically induced skin inflammation; however, the mechanism by which IFN-γ-producing cells are recruited to the sites of inflammation remains undefined. Secretion of macrophage migration inhibitory factor (MIF), a proinflammatory cytokine, from damaged cells may promote immune cell recruitment. We hypothesized that MIF triggers an initial step in the chemotaxis of IFN-γ-producing cells in chemically induced skin inflammation. Using acute and chronic models of 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced skin inflammation in mouse ears, MIF expression was examined, and its role in this process was investigated pharmacologically. The cell populations targeted by MIF, their receptor expression patterns, and the effects of MIF on cell migration were examined. TPA directly caused cytotoxicity accompanied by MIF release in mouse ear epidermal keratinocytes, as well as in human keratinocytic HaCaT cells. Treatment with the MIF antagonist (S,R)-3-(4-hydroxyphenyl)-4,5-dihydro-5-isoxazole acetic acid methyl ester considerably attenuated TPA-induced ear swelling, leukocyte infiltration, epidermal cell proliferation, and dermal angiogenesis. Inhibition of MIF greatly diminished the dermal infiltration of IFN-γ(+) NKT cells, whereas the addition of exogenous TPA and MIF to NKT cells promoted their IFN-γ production and migration, respectively. MIF specifically triggered the chemotaxis of NKT cells via CD74 and CXCR2, and the resulting depletion of NKT cells abolished TPA-induced skin inflammation. In TPA-induced skin inflammation, MIF is released from damaged keratinocytes and then triggers the chemotaxis of CD74(+)CXCR2(+) NKT cells for IFN-γ production.

Macrophage migration inhibitory factor (MIF) -173 polymorphism is associated with clinical erythema nodosum in Löfgren's syndrome

INTRODUCTION

Macrophage migration inhibitory factor (MIF) has been shown to be a key regulator in innate and adaptive immune responses. A single nucleotide polymorphism in the 5' region of the MIF gene, MIF -173∗G/C, is associated with increased MIF protein production, in vivo and in vitro. Associations have been shown between the minor MIF -173C allele and sarcoidosis patients with erythema nodosum (EN). Löfgren's syndrome is an acute and usually self-remitting phenotype of sarcoidosis. It is defined as having an acute onset with bilateral hilar lymphadenopathy (BHL), fever, erythema nodosum (EN) and/or arthritis. The aim of this study was to investigate whether MIF -173G/C associates with the susceptibility to and the clinical manifestations, i.e. arthritis or EN, of Löfgren's syndrome. A total of 171 patients with Löfgren's syndrome and 313 controls were genotyped for a single nucleotide polymorphism at position -173 of the MIF gene (SNP rs755622), using a PCR and a restriction enzyme technique.

RESULTS

There were no significant differences found in the MIF -173C allele frequencies between patients with Löfgren's syndrome and controls. In patients with Löfgren's syndrome with only EN, a significantly increased frequency of the C minor allele was observed compared to patients with arthritis only (p=0.0095; OR 3.08, CI: 1.28-7.39). Patients with only EN compared to patients with EN and arthritis showed a significantly increased frequency of the minor C allele (p=0.044; OR 1.97, CI: 1.01-3.85). But patients with only arthritis compared to patients with EN and arthritis did not show a significant difference in C allele frequency (p=0.270; OR 0.64, CI: 0.29-1.42).

CONCLUSIONS

The MIF -173C allele is associated with erythema nodosum in Löfgren's syndrome, but not with susceptibility to sarcoidosis. This indicates a role for MIF after antigen presenting to the T cell has taken place and the sarcoid inflammatory response has begun.

MIF antagonist (CPSI-1306) protects against UVB-induced squamous cell carcinoma

Macrophage migration inhibitory factor (MIF) is a homotrimeric proinflammatory cytokine implicated in chronic inflammatory diseases and malignancies, including cutaneous squamous cell carcinomas (SCC). To determine whether MIF inhibition could reduce UVB light-induced inflammation and squamous carcinogenesis, a small-molecule MIF inhibitor (CPSI-1306) was utilized that disrupts homotrimerization. To examine the effect of CPSI-1306 on acute UVB-induced skin changes, Skh-1 hairless mice were systemically treated with CPSI-1306 for 5 days before UVB exposure. In addition to decreasing skin thickness and myeloperoxidase (MPO) activity, CPSI-1306 pretreatment increased keratinocyte apoptosis and p53 expression, decreased proliferation and phosphohistone variant H2AX (γ-H2AX), and enhanced repair of cyclobutane pyrimidine dimers. To examine the effect of CPSI-1306 on squamous carcinogenesis, mice were exposed to UVB for 10 weeks, followed by CPSI-1306 treatment for 8 weeks. CPSI-1306 dramatically decreased the density of UVB-associated p53 foci in non-tumor-bearing skin while simultaneously decreasing the epidermal Ki67 proliferation index. In addition to slowing the rate of tumor development, CPSI-1306 decreased the average tumor burden per mouse. Although CPSI-1306-treated mice developed only papillomas, nearly a third of papillomas in vehicle-treated mice progressed to microinvasive SCC. Thus, MIF inhibition is a promising strategy for prevention of the deleterious cutaneous effects of acute and chronic UVB exposure.

IMPLICATIONS

Macrophage migration inhibitory factor is a viable target for the prevention of UVB-induced cutaneous SSCs.

Relationship of macrophage migration inhibitory factor levels in PBMCs, lesional skin and serum with disease severity and activity in vitiligo vulgaris

Melanocyte loss in vitiligo vulgaris is believed to be an autoimmune process. Macrophage migration inhibitory factor (MIF) is involved in many autoimmune skin diseases. We determined the possible role of MIF in the pathogenesis of vitiligo vulgaris, and describe the relationship between MIF expressions and disease severity and activity. Serum MIF concentrations and mRNA levels in PBMCs were measured in 44 vitiligo vulgaris patients and 32 normal controls, using ELISA and real-time RT-PCR. Skin biopsies from 15 patients and 6 controls were analyzed by real-time RT-PCR. Values are reported as median (25th-75th percentile). Serum MIF concentrations were significantly increased in patients [35.81 (10.98-43.66) ng/mL] compared to controls [7.69 (6.01-9.03) ng/mL]. MIF mRNA levels were significantly higher in PBMCs from patients [7.17 (3.59-8.87)] than controls [1.67 (1.23-2.42)]. There was also a significant difference in MIF mRNA levels in PBMCs between progressive and stable patients [7.86 (5.85-9.13) vs 4.33 (2.23-8.39)] and in serum MIF concentrations [40.47 (27.71-46.79) vs 26.80 (10.55-36.07) ng/mL]. In addition, the vitiligo area severity index scores of patients correlated positively with changes of both serum MIF concentrations (r = 0.488) and MIF mRNA levels in PBMCs (r = 0.426). MIF mRNA levels were significantly higher in lesional than in normal skin [2.43 (2.13-7.59) vs 1.18 (0.94-1.83)] and in patients in the progressive stage than in the stable stage [7.52 (2.43-8.84) vs 2.13 (1.98-2.64)]. These correlations suggest that MIF participates in the pathogenesis of vitiligo vulgaris and may be useful as an index of disease severity and activity.

Serum level of macrophage migration inhibitory factor (MIF) in Egyptians with alopecia areata and its relation to the clinical severity of the disease

BACKGROUND

Alopecia areata (AA) is a common dermatological problem that manifests as sudden loss of hair without any inflammation or scarring. Various cytokines are implicated in the pathogenesis of this disease. Macrophage migration inhibitory factor (MIF) is located at an upstream position in the events leading to the possible dysregulated immuno-inflammatory responses, and the high level of this cytokine in AA may suggest a role of MIF in the pathogenesis of AA.

METHODS

This case-control study was carried out on 31 AA patients with different grades of severity and 15 apparently healthy subjects. Serum MIF level was measured by ELISA, and was correlated with the clinical severity of the disease using SALT (severity of alopecia tool) scoring system.

RESULTS

In this study, there was a significant elevation in serum MIF levels in AA patients in comparison with controls. There was also a positive correlation between MIF levels and clinical severity and disease duration.

CONCLUSION

MIF seems to have an essential role in the etiopathogenesis of AA. So, it is considered to be a promising target in the therapy of autoimmune diseases and as a future predictor of alopecia activity. Anti-MIF therapy might be added as one of the new biological treatments for AA.

Haplotype differences for copy number variants in the 22q11.23 region among human populations: a pigmentation-based model for selective pressure

Two gene clusters are tightly linked in a narrow region of chromosome 22q11.23: the macrophage migration inhibitory factor (MIF) gene family and the glutathione S-transferase theta class. Within 120 kb in this region, two 30-kb deletions reach high frequencies in human populations. This gives rise to four haplotypic arrangements, which modulate the number of genes in both families. The variable patterns of linkage disequilibrium (LD) between these copy number variants (CNVs) in diverse human populations remain poorly understood. We analyzed 2469 individuals belonging to 27 human populations with different ethnic origins. Then we correlated the genetic variability of 22q11.23 CNVs with environmental variables. We confirmed an increasing strength of LD from Africa to Asia and to Europe. Further, we highlighted strongly significant correlations between the frequency of one of the haplotypes and pigmentation-related variables: skin color (R(2)=0.675, P<0.001), distance from the equator (R(2)=0.454, P<0.001), UVA radiation (R(2)=0.439, P<0.001), and UVB radiation (R(2)=0.313, P=0.002). The fact that all MIF-related genes are retained on this haplotype and the evidences gleaned from experimental systems seem to agree with the role of MIF-related genes in melanogenesis. As such, we propose a model that explains the geographic and ethnic distribution of 22q11.23 CNVs among human populations, assuming that MIF-related gene dosage could be associated with adaptation to low UV radiation.

Identification and expression of macrophage migration inhibitory factor in Sarcoptes scabiei

Macrophage migration inhibitory factor (MIF) is a pleiotropic proinflammatory cytokine produced by many mammalian tissues including skin. It is also found in many invertebrate parasites of mammals including ticks and may function to aid the parasite to evade the innate and adaptive immune responses in the host. In this study, the cDNA for a MIF gene was sequenced from Sarcoptes scabiei, the scabies mite, using RT-PCR and RACE molecular techniques. The resulting nucleotide sequence had a length of 405 base pairs and the putative amino acid sequences for the mite and tick (Dermacentor variabilis) proteins were identical. The initial steps for the project resulted in the production of expressed scabies mite cDNAs. A real time (qPCR) assay was performed with MIF from scabies mites and various tick species. Results show that mRNA encoding MIF homologues was three times more abundant in the mite samples when compared to RNA prepared from D. variabilis salivary glands and 1.3 times more abundant when compared with RNA prepared from D. variabilis midgut.

Macrophage migration inhibitory factor as an incriminating agent in dermatological disorders

Macrophage migration inhibitory factor (MIF) is a critical immunoregulatory pluripotent cytokine. It has been re-evaluated as a proinflammatory cytokine, pituitary hormone and glucocorticoid-induced immunoregulatory protein. MIF exists in human epidermis, especially in the basal layer and also is expressed constitutively by monocytes/macrophages, T cells, B cells, endocrine, and epithelial cells. In the field of dermatology, MIF is believed to be a detrimental factor in inflammatory dermatological diseases including atopic dermatitis (AD), psoriasis, vitiligo, pemphigus vulgaris, bullous pemphigoid (BP), alopecia areata (AA) as well as other conditions such as photoaging, and photocarcinigenesis. The objective of this review is to gather and summarize MIF related disorders in dermatology and present valuable information for readers and researchers.

Macrophage migration inhibitory factor gene polymorphism is not associated with pemphigus vulgaris in Iranian patients

BACKGROUND

Promoter polymorphisms of the macrophage migration inhibitory factor gene are associated with increased production of macrophage migration inhibitory factor. Elevated levels of macrophage migration inhibitory factor have been observed in the sera of patients with pemphigus vulgaris. More than this, macrophage migration inhibitory factor promoter gene polymorphism has been found to confer increased risk of susceptibility to chronic inflammatory diseases.

OBJECTIVE

We investigated whether there is an association between promoter polymorphism of the macrophage migration inhibitory factor gene and pemphigus vulgaris.

METHODS

One hundred and six patients with pemphigus vulgaris, and a control panel of one hundred healthy volunteers were genotyped for a single nucleotide polymorphism identified in the 5'-flanking region at the position -173 of the gene, using polymerase chain reaction-restriction fragment length analysis.

RESULTS

We found a notably high prevalence of C/C genotype in our nation but no significant difference was observed between patients and controls.

CONCLUSION

The result of this study using a large and well documented trial of patients showed that macrophage migration inhibitory factor -173G-C polymorphism is not associated with pemphigus vulgaris; but as the role of macrophage migration inhibitory factor in the inflammatory process has not been delineated in detail and the prevalence of C/C genotype is notably higher in our nation, this finding merits more consideration.

Tissue-Specific Effects of Loss of Estrogen during Menopause and Aging

The roles of estrogens have been best studied in the breast, breast cancers, and in the female reproductive tract. However, estrogens have important functions in almost every tissue in the body. Recent clinical trials such as the Women's Health Initiative have highlighted both the importance of estrogens and how little we know about the molecular mechanism of estrogens in these other tissues. In this review, we illustrate the diverse functions of estrogens in the bone, adipose tissue, skin, hair, brain, skeletal muscle and cardiovascular system, and how the loss of estrogens during aging affects these tissues. Early transcriptional targets of estrogen are reviewed in each tissue. We also describe the tissue-specific effects of selective estrogen receptor modulators (SERMs) used for the treatment of breast cancers and postmenopausal symptoms.

UV-B radiation induces macrophage migration inhibitory factor-mediated melanogenesis through activation of protease-activated receptor-2 and stem cell factor in keratinocytes

UV radiation indirectly regulates melanogenesis in melanocytes through a paracrine regulatory mechanism involving keratinocytes. Protease-activated receptor (PAR)-2 activation induces melanosome transfer by increasing phagocytosis of melanosomes by keratinocytes. This study demonstrated that macrophage migration inhibitory factor (MIF) stimulated PAR-2 expression in human keratinocytes. In addition, we showed that MIF stimulated stem cell factor (SCF) release in keratinocytes; however, MIF had no effect on the release of endothelin-1 or prostaglandin E2 in keratinocytes. In addition, MIF had no direct effect on melanin and tyrosinase synthesis in cultured human melanocytes. The effect of MIF on melanogenesis was also examined using a three-dimensional reconstituted human epidermal culture model, which is a novel, commercially available, cultured human epidermis containing functional melanocytes. Migration inhibitory factor induced an increase in melanin content in the epidermis after a 9-day culture period. Moreover, melanin synthesis induced by UV-B stimulation was significantly down-regulated by anti-MIF antibody treatment. An in vivo study showed that the back skin of MIF transgenic mice had a higher melanin content than that of wild-type mice after 12 weeks of UV-B exposure. Therefore, MIF-mediated melanogenesis occurs mainly through the activation of PAR-2 and SCF expression in keratinocytes after exposure to UV-B radiation.

Macrophage migration inhibitory factor is essential for eosinophil recruitment in allergen-induced skin inflammation

Macrophage migration inhibitory factor (MIF) is a pluripotent cytokine that has an essential role in the pathophysiology of experimental allergic inflammation. Recent findings suggest that MIF is involved in several allergic disorders, including atopic dermatitis (AD). In this study, the role of MIF in allergic skin inflammation was examined using a murine model of AD elicited by epicutaneous sensitization with ovalbumin (OVA). We observed the number of skin-infiltrating eosinophils to significantly increase in OVA-sensitized MIF transgenic (Tg) mice compared with their wild-type (WT) littermates. On the other hand, eosinophils were virtually absent from the skin of MIF knockout (KO) mice and failed to infiltrate their skin after repeated epicutaneous sensitization with OVA. The mRNA expression levels of eotaxin and IL-5 were significantly increased in OVA-sensitized skin sites of MIF Tg mice, but were significantly decreased in MIF KO mice in comparison with the levels in WT littermates. Eotaxin expression was induced by IL-4 stimulation in fibroblasts in MIF Tg mice, but not in MIF KO mice. These findings indicate that MIF can induce eosinophil accumulation in the skin. Therefore, the targeted inhibition of MIF might be a promising new therapeutic strategy for allergic skin diseases.

The Role of Macrophage Migration Inhibitory Factor (MIF) in Ultraviolet Radiation-Induced Carcinogenesis

Ultraviolet (UV) radiation is the most common cause of physical injury to the skin due to environmental damage, and UV exposure substantially increases the risk of actinic damage to the skin. The inflammatory changes induced by acute UV exposure include erythema (sunburn) of the skin, while chronic exposure to solar UV radiation causes photo-aging, immunosuppression, and ultimately, carcinogenesis of the skin. After skin damage by UV radiation, the cells are known to secrete many cytokines, including interleukin (IL)-1, IL-6, tumor necrosis factor (TNF)-α. and macrophage migration inhibitory factor (MIF). MIF was originally identified as a lymphokine that concentrates macrophages at inflammatory loci, and is known to be a potent activator of macrophages in vivo. MIF is considered to play an important role in cell-mediated immunity. Since the molecular cloning of MIF cDNA, MIF has been re-evaluated as a proinflammatory cytokine and pituitary-derived hormone that potentiates endotoxemia. MIF is ubiquitously expressed in various tissues, including the skin. Recent studies have suggested a potentially broader role for MIF in growth regulation because of its ability to antagonize p53-mediated gene activation and apoptosis. This article reviews the latest findings on the roles of MIF with regard to UV-induced skin cancer.

DNA vaccination against macrophage migration inhibitory factor improves atopic dermatitis in murine models

BACKGROUND

Atopic dermatitis (AD) is a common chronic inflammatory skin disease. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine that has been implicated in the pathogenesis of AD. Recently, we developed a novel DNA vaccine that generates neutralizing endogenous anti-MIF antibodies.

OBJECTIVE

This study explores the preventive and therapeutic effects of this MIF-DNA vaccine in mouse models of AD.

METHODS

Two different AD model mice (DS-Nh and NC/Nga) received MIF-DNA vaccination to analyze preventive and therapeutic effects, as assessed by clinical skin scores, histologic findings, and serum IgE levels.

RESULTS

In murine models of AD, MIF-DNA vaccination prevented the occurrence of the AD skin phenotype. Furthermore, administration of MIF-DNA vaccine to mice that had already developed AD produced a rapid improvement in AD skin manifestation. There were reduced histologic signs of inflammation and lower serum IgE levels in treated mice compared with those seen in control animals. Finally, passive transfer of IgG from MIF-DNA vaccinated mice to AD mice also produced a significant therapeutic effect. These results demonstrate that MIF-DNA vaccination not only prevents the development of AD but also improves the symptoms of pre-existing AD.

CONCLUSION

Taken together, the induction of an anti-MIF autoantibody response using MIF-DNA vaccination appears to be a useful approach in the treatment of AD.

Macrophage migration inhibitory factor (MIF), enzymatic activity and the inflammatory response

Macrophage migration inhibitory factor represents a key cytokine in human diseases. It plays an important role in both innate and acquired immunity and has been shown to be a key mediator of inflammatory diseases. More recently MIF has been implicated in cancer pathogenesis. Over the decades its structure and functions have been elucidated and this has led to it being further classified as a hormone and an enzyme. It has isomerase enzymatic activity and increasing evidence implicates this activity in inflammatory disease. Consequently, there is increasing interest in developing small molecular weight inhibitors which could target this novel enzymatic activity in disease. (c) 2009 International Union of Biochemistry and Molecular Biology, Inc.