Calcipotriol and betamethasone dipropionate exhibit different immunomodulatory effects on imiquimod-induced murine psoriasiform dermatitis.

Psoriasis is a T-helper (Th)1/Th17-mediated, chronic inflammatory dermatitis that is commonly treated with topical corticosteroids and vitamin D analogs. The combination of a topical corticosteroid and vitamin D analog showed superior efficacy to each alone in clinical trials; however, the mechanisms by which the topical corticosteroid and vitamin D analog exert their effects on lesional skin in combination and each alone remain unknown. In this study, we examined the effects of combined calcipotriol (Cal)/betamethasone dipropionate (BD) ointment on psoriasis in vivo, utilizing imiquimod (IMQ)-induced murine psoriasiform skin inflammation, compared with each alone.

The vitamin D analog, maxacalcitol, reduces psoriasiform skin inflammation by inducing regulatory T cells and downregulating IL-23 and IL-17 production.

Background: Psoriasis is a Th1/Th17-mediated inflammatory dermatosis treated with topical corticosteroids and vitamin D analogs (VD3 As).

Objective: To compare the effects of a VD3 A maxacalcitol and betamethasone valerate (BV) steroid lotion on topical imiquimod (IMQ)-induced psoriasiform skin inflammation.

Methods: Female BALB/c mice were treated with vehicle, maxacalcitol or BV lotion on the skin for 3 days, and IMQ cream for 6 days.

Evaluation of IgG4+ Plasma Cell Infiltration in Patients with Systemic Plasmacytosis and Other Plasma Cell-infiltrating Skin Diseases.

Systemic plasmacytosis is a rare skin disorder characterized by marked infiltration of plasma cells in the dermis. IgG4-related disease is pathologically characterized by lymphoplasmacytic infiltration rich in IgG4+ plasma cells, storiform fibrosis, and obliterative phlebitis, accompanied by elevated levels of serum IgG4. Reports of cases of systemic plasmacytosis with abundant infiltration of IgG4+ plasma cells has led to discussion about the relationship between systemic plasmacytosis and IgG4-related disease.

Lipocalin-2 exacerbates psoriasiform skin inflammation by augmenting T-helper 17 response.

Lipocalin-2 (LCN2) is an antimicrobial protein and adipokine associated with insulin resistance, obesity and atherosclerotic disease. Psoriasis is a T-helper (Th)1/Th17-mediated, chronic inflammatory dermatosis related to metabolic syndromes and serum LCN2 levels are elevated in psoriatic patients. We examined the in vivo effects of LCN2 on topical imiquimod (IMQ)-induced psoriasiform skin in BALB/c mice and in vitro on human keratinocytes (KC).

Adiponectin regulates psoriasiform skin inflammation by suppressing IL-17 production from γδ-T cells.

Accumulating epidemiologic evidence has revealed that metabolic syndrome is an independent risk factor for psoriasis development and is associated with more severe psoriasis. Adiponectin, primarily recognized as a metabolic mediator of insulin sensitivity, has been newly drawing attention as a mediator of immune responses. Here we demonstrate that adiponectin regulates skin inflammation, especially IL-17-related psoriasiform dermatitis.

Immunoresponses in dermatomycoses.

Contact with fungal pathogens initiates a series of host responses beginning with innate immunity, which leads to fungal recognition and microbial killing. The innate immune system also modulates the adaptive immune responses, leading to the establishment of immunological memory and protection against pathogens. In the case of dimorphic fungi such as Candida albicans and Malassezia, the immune system plays an important role in tolerance and resistance when managing the organisms either as commensal microbiota or invading pathogens, and disruption of this balance can result in pathological consequences for the host.

Antimycotics suppress the Malassezia extract-induced production of CXC chemokine ligand 10 in human keratinocytes.

Malassezia, a lipophilic yeast, exacerbates atopic dermatitis. Malassezia products can penetrate the disintegrated stratum corneum and encounter subcorneal keratinocytes in the skin of atopic dermatitis patients. Type 1 helper T (Th1) cells infiltrate chronic lesions with atopic dermatitis, and antimycotic agents improve its symptoms.

Suppressive effects of antimycotics on thymic stromal lymphopoietin production in human keratinocytes.

Background: Thymic stromal lymphopoietin (TSLP) is produced by epidermal keratinocytes, and it induces Th2-mediated inflammation. TSLP expression is enhanced in lesions with atopic dermatitis, and is a therapeutic target. Antimycotic agents improve the symptoms of atopic dermatitis.

Visfatin enhances the production of cathelicidin antimicrobial peptide, human β-defensin-2, human β-defensin-3, and S100A7 in human keratinocytes and their orthologs in murine imiquimod-induced psoriatic skin.

Psoriasis, a chronic inflammatory dermatosis, is frequently associated with metabolic disorders, suggesting that adipokines are involved in its pathogenesis. We recently reported that the adipokine visfatin activates NF-κB and STAT3 in keratinocytes. Antimicrobial peptide expression is enhanced in psoriatic lesions and may promote disease development.

Adiponectin regulates cutaneous wound healing by promoting keratinocyte proliferation and migration via the ERK signaling pathway.

Diabetic patients are at high risk of developing delayed cutaneous wound healing. Adiponectin plays a pivotal role in the pathogenesis of diabetes and is considered to be involved in various pathological conditions associated with diabetes; however, its role in wound repair is unknown. In this study, we elucidated the involvement of adiponectin in cutaneous wound healing in vitro and in vivo.

P2Y6 receptor signaling pathway mediates inflammatory responses induced by monosodium urate crystals.

Gout occurs in individuals with hyperuricemia when monosodium urate (MSU) crystals precipitate in tissues and induce acute inflammation via phagocytic cells such as monocytes. MSU crystals have been demonstrated in skin diseases such as tophaceous gout or psoriasis; however, the importance of MSU crystals in the skin is totally unknown. In this study, we found that MSU crystals, through P2Y(6) receptors, stimulated normal human keratinocytes (NHK) to produce IL-1α, IL-8/CXCL8, and IL-6.

High calcium, ATP, and poly(I:C) augment the immune response to β-glucan in normal human epidermal keratinocytes.

β-Glucans are pathogen-associated molecular patterns of fungi such as Candida albicans. Here, we studied their effects on normal human epidermal keratinocytes (NHEKs) from neonatal foreskin, and with high calcium to induce keratinocyte differentiation, danger signals, and pathogen-associated compounds such as adenosine 5'-triphosphate (ATP), poly(I:C), and lipopolysaccharide (LPS). β-Glucan stimulation significantly increased IL-8, IL-6, and IL-1α production by NHEKs.

Identification of a novel marker for dendritic cell maturation, mouse transmembrane protein 123.

Dendritic cells (DCs) are a group of professional antigen-presenting cells, and many genes are known to be associated with their maturation. We compared the transcriptional profiles of immature and mature mouse Langerhans cells using the suppressive, subtractive hybridization method and identified a novel gene of unknown function, termed herein transmembrane protein 123 (Tmem123), of which mRNA expression was enhanced in mature but not in immature Langerhans cells. Its expression was also enhanced in other mature DCs such as bone marrow-derived DCs (BMDCs) and splenic DCs.

Histamine induces human beta-defensin-3 production in human keratinocytes.

Background: The antimicrobial peptide human beta-defensin-3 (hBD-3) is produced by epidermal keratinocytes, and promotes cutaneous antimicrobial defense, inflammation, and wound repair. hBD-3 induces histamine release from mast cells. We previously showed that histamine enhanced transcriptional activity of activator protein-1 (AP-1) in human keratinocytes by inducing the expression of AP-1 component c-Fos via the activation of extracellular signal-regulated kinase (ERK) through H1 receptors.