ABSTRACT
Malassezia form the dominant eukaryotic microbial community on the human skin. The Malassezia genus possesses a repertoire of secretory hydrolytic enzymes involved in protein and lipid metabolism which alter the external cutaneous environment. The exact role of most Malassezia secreted enzymes, including those in interaction with the epithelial surface, is not well characterized. In this study, we compared the expression level of secreted proteases, lipases, phospholipases, and sphingomyelinases of Malassezia globosa in healthy subjects and seborrheic dermatitis or atopic dermatitis patients. We observed upregulated gene expression of the previously characterized secretory aspartyl protease MGSAP1 in both diseased groups, in lesional and non-lesional skin sites, as compared to healthy subjects. To explore the functional roles of MGSAP1 in skin disease, we generated a knockout mutant of the homologous protease MFSAP1 in the genetically tractable Malassezia furfur. We observed the loss of MFSAP1 resulted in dramatic changes in the cell adhesion and dispersal in both culture and a human 3D reconstituted epidermis model. In a murine model of Malassezia colonization, we further demonstrated Mfsap1 contributes to inflammation as observed by reduced edema and inflammatory cell infiltration with the knockout mutant versus wildtype. Taken together, we show that this dominant secretory Malassezia aspartyl protease has an important role in enabling a planktonic cellular state that can potentially aid in colonization and additionally as a virulence factor in barrier-compromised skin, further highlighting the importance of considering the contextual relevance when evaluating the functions of secreted microbial enzymes.
Subject(s)
Aspartic Acid Proteases , Dermatitis, Atopic , Malassezia , Humans , Animals , Mice , Peptide Hydrolases/genetics , Malassezia/genetics , Inflammation , Aspartic Acid EndopeptidasesABSTRACT
BACKGROUND: Eblasakimab, an interleukin (IL)-13 receptor α1 antagonist, blocks IL-4 and IL-13 signaling through the type 2 receptor. OBJECTIVE: The safety and efficacy of eblasakimab was evaluated in adults with moderate-to-severe atopic dermatitis (AD). METHODS: In this phase 1b randomized, double-blinded study, 52 patients with moderate-to-severe AD received weekly subcutaneous injections of eblasakimab 200, 400, or 600 mg, or placebo for 8 weeks. Primary outcome was the incidence of treatment-emergent adverse events. Secondary outcomes included percentage change in the Eczema Area and Severity Index from baseline; Eczema Area and Severity Index improvement of at least 50%, 75%, or 90% from baseline; and percentage change in the peak-pruritus numeric rating scale score from baseline. RESULTS: Treatment-emergent adverse events were reported in 47% placebo and 71% eblasakimab patients; most were considered mild or moderate and did not lead to study discontinuation. At week 8 eblasakimab 600 mg showed statistically significant improvement in mean percentage change in Eczema Area and Severity Index versus placebo (-65% vs -27%, P = .014). Other key secondary physician- and patient-reported end points were met. LIMITATIONS: Longer studies are required to confirm eblasakimab safety and efficacy in AD patients. CONCLUSIONS: Treatment of adults with moderate-to-severe AD with eblasakimab was well-tolerated and associated with significant clinical improvements versus placebo.
Subject(s)
Dermatitis, Atopic , Eczema , Adult , Humans , Dermatitis, Atopic/diagnosis , Dermatitis, Atopic/drug therapy , Dermatitis, Atopic/chemically induced , Antibodies, Monoclonal/adverse effects , Receptors, Interleukin-13/therapeutic use , Treatment Outcome , Severity of Illness Index , Double-Blind Method , Eczema/drug therapySubject(s)
Hypopigmentation , Vitiligo , Humans , Self-Assessment , Severity of Illness Index , Vitiligo/diagnosisABSTRACT
The Vitiligo Global Issues Consensus Conference (VGICC), through an international e-Delphi consensus, concluded that 'repigmentation' and 'maintenance of gained repigmentation' are essential core outcome measures in future vitiligo trials. This VGICC position paper addresses these core topics in two sections and includes an atlas depicting vitiligo repigmentation patterns and color match. The first section delineates mechanisms and characteristics of vitiligo repigmentation, and the second section summarizes the outcomes of international meeting discussions and two e-surveys on vitiligo repigmentation, which had been carried out over 3 yr. Treatment is defined as successful if repigmentation exceeds 80% and at least 80% of the gained repigmentation is maintained for over 6 months. No agreement was found on the best outcome measure for assessing target or global repigmentation, therefore highlighting the limitations of e-surveys in addressing clinical measurements. Until there is a clear consensus, existing tools should be selected according to the specific needs of each study. A workshop will be conducted to address the remaining issues so as to achieve a consensus.
Subject(s)
Skin Pigmentation , Vitiligo/therapy , Congresses as Topic , Consensus , Humans , Treatment OutcomeABSTRACT
BACKGROUND: Progressive macular hypomelanosis is an acquired disorder characterized by hypopigmented macules mostly on the trunk and upper extremities. Although many treatment modalities have been proposed for this condition with variable success rates, there are few reports comparing their efficacy and relapse rates. AIM: To compare the efficacy and relapse rates of different treatment modalities for progressive macular hypomelanosis. METHODS: Case records of patients diagnosed with progressive macular hypomelanosis and treated in National Skin Centre for a six year period between 2008 and 2014 were reviewed. Patient demographics, distribution of hypopigmented macules, treatment efficacy and relapse rates were noted. RESULTS: A total of 108 patients were seen for progressive macular hypomelanosis over the study period; of these, 40 opted for no treatment but were followed up. Thirty-six were treated with topical antimicrobials and 32 with phototherapy. Of those untreated, 23% recovered spontaneously while 38% in the antimicrobial group and 90% in the phototherapy had remission of their hypopigmentation. After 2 years of follow-up, relapse occurred only in the phototherapy group. LIMITATIONS: The main limitation is the retrospective design whereby diagnosis is dependent on the attending dermatologist. CONCLUSIONS: Narrow-band ultraviolet B therapy appears to be the most effective treatment for progressive macular hypomelanosis but also has the highest potential for relapse. Response rates for antimicrobial therapy are lower and slower, but patients who responded did not relapse. A combination of topical/systemic antimicrobials with narrow-band ultraviolet B therapy might be the best option to hasten recovery and minimize relapse.
Subject(s)
Anti-Infective Agents/administration & dosage , Disease Progression , Hypopigmentation/diagnosis , Hypopigmentation/therapy , Macula Lutea/pathology , Phototherapy/trends , Administration, Topical , Adolescent , Adult , Female , Follow-Up Studies , Humans , Macula Lutea/drug effects , Male , Recurrence , Retrospective Studies , Treatment Outcome , Young AdultABSTRACT
A prospective study was performed to assess the usefulness of desmoglein enzyme-linked immunosorbent assay testing compared with indirect immunofluorescence in the diagnosis of new cases of pemphigus, as well as to compare the relative sensitivities of monkey oesophagus and normal human skin as substrates for indirect immunofluorescence. These tests were performed on the sera of 29 consecutive new cases of pemphigus diagnosed over a 2-year period based on clinical, histological and direct immunofluorescence findings. Desmoglein enzyme-linked immunosorbent assay was positive in all patients whereas indirect immunofluorescence was positive in only 25 of 29 patients. All four patients with negative indirect immunofluorescence had positive antinuclear antibodies or cytoplasmic fluorescence that could have masked the anti-intercellular antibodies. Desmoglein enzyme-linked immunosorbent assay appeared to reflect the disease activity better than indirect immunofluorescence in a few patients who had active disease of recent onset. Monkey oesophagus was found to be superior or equal to human skin as a substrate for indirect immunofluorescence in both pemphigus vulgaris and foliaceus.