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INTRODUCTION: Felix Pinkus' concept of the vitreous membrane (VM) published in 1927 describes circular folds protruding into the outer root sheath (ORS), which, in his opinion, serve as interdigitations between the outer root sheath (ORS) and the VM. This concept currently seems to have fallen into oblivion. OBJECTIVE: To determine the origin and possible function of the VM in the proliferation and vascularization of the hair follicle (HF). METHODS: Serial investigation of healthy skin probes with histological (hematoxylin & eosin and periodic acid-Schiff) and immunohistochemical examination (Ki67, CD56, CD8, and collagen IV) were performed. RESULTS: Morphological variations of the VM in various HFs such as protrusions and folds, the latter unilateral, bilateral or circular, some acute-angled, were found. Similarly, protrusions of the VM into the ORS were observed, that consisted of capillary tissue together with perifollicular tissue and VM mimicking minimal variants of the dermal papilla. CONCLUSIONS: Pinkus' concept of the VM is revisited, reproduced and possible functions are proposed. Since these structures are found in a HF region with a high metabolic dynamism, they may be involved in differentiation or nutrition, or else be formed as a result of pressure arising from outgrowing hair shafts.
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OBJECTIVE: Comparison of fluorescence optical imaging (FOI) with grayscale (GS) and power Doppler ultrasound (PDUS) to detect joint inflammation in patients with confirmed or suspected psoriatic arthritis (PsA). METHODS: Patients (n = 60) with psoriasis and tenderness and/or swelling of joints were separated into two groups: diagnosis confirmed by the treating dermatologist before the start of the study (n = 26), and suspected PsA (n = 34). GS/PDUS of the hand most clinically affected was performed with a dorsal/palmar view (wrist, MCP, PIP, DIP2-5). FOI examination was carried out in a standardized manner by analyzing the predefined Phases 1-3. RESULTS: FOI was found to be more sensitive than ultrasound (US) for detection of inflammation in PIP/DIP joints (p = 0.035). Confirmed PsA patients showed more findings in FOI P2 and P3, while suspected PsA patients showed more findings in P1. In the confirmed PsA group, most involved joints were MCP joints, while in the suspected PsA group, more involved wrist joints and DIP joints (p = 0.006) were detected with FOI. CONCLUSIONS: The differences between the confirmed and suspected groups indicate that FOI is helpful in the detection of early PsA since P1 may correspond to acute inflammation, whereas P2 and P3 enhancement reflect chronic inflammation. Fluorescence optical imaging might therefore be a novel diagnostic tool for early PsA diagnosis.
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Artrite Psoriásica/diagnóstico por imagem , Adulto , Idoso , Diagnóstico Precoce , Edema/diagnóstico por imagem , Feminino , Articulações dos Dedos/diagnóstico por imagem , Dermatoses da Mão/diagnóstico por imagem , Humanos , Masculino , Microscopia de Fluorescência/métodos , Pessoa de Meia-Idade , Dor Musculoesquelética/diagnóstico por imagem , Imagem Óptica/métodos , Ultrassonografia , Articulação do Punho/diagnóstico por imagemRESUMO
Hidradenitis suppurativa (HS) (also designated acne inversa) is a chronic inflammatory disease characterized by painful purulent skin lesions and progressive destruction of skin architecture. Despite the high burden for the patients, pathogenetic pathways underlying HS alterations remain obscure. When we examined the HS cytokine pattern, IL-1ß turned out to be a highly prominent cytokine, overexpressed even compared with psoriatic lesions. Analyses of IL-1ß-induced transcriptome in various cell types showed overlapping profiles, with upregulations of molecules causing immune cell infiltration and extracellular matrix degradation, and of specific cytokines including IL-6, IL-32, and IL-36. Matching cellular IL-1 receptor levels, dermal fibroblasts showed both the strongest and broadest IL-1ß response, which was not clearly shared or strengthened by other cytokines. The IL-1ß signature was specifically present in HS lesions and could be reversed by application of IL-1 receptor antagonist. Search for blood parameters associated with IL-1ß pathway activity in HS identified serum amyloid A, which was synergistically induced by IL-1ß and IL-6 in hepatocytes. Consequently, strongly elevated blood serum amyloid A levels in HS correlated positively with the extent of inflammatory skin alterations. In summary, the IL-1ß pathway represents a pathogenetic cascade, whose activity may be therapeutically targeted and monitored by blood SAA levels.
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Hidradenite Supurativa/imunologia , Interleucina-1beta/metabolismo , Interleucina-6/metabolismo , Receptores de Interleucina-1/metabolismo , Adulto , Biópsia , Estudos de Casos e Controles , Células Cultivadas , Matriz Extracelular/imunologia , Matriz Extracelular/metabolismo , Feminino , Fibroblastos/imunologia , Fibroblastos/metabolismo , Hepatócitos/imunologia , Hepatócitos/metabolismo , Hidradenite Supurativa/sangue , Hidradenite Supurativa/patologia , Humanos , Proteína Antagonista do Receptor de Interleucina 1/metabolismo , Interleucina-1beta/imunologia , Interleucina-6/imunologia , Queratinócitos/imunologia , Queratinócitos/metabolismo , Masculino , Pessoa de Meia-Idade , Cultura Primária de Células , Receptores de Interleucina-1/antagonistas & inibidores , Proteína Amiloide A Sérica/análise , Proteína Amiloide A Sérica/imunologia , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/imunologia , Pele/citologia , Pele/imunologia , Pele/patologia , Regulação para Cima , Adulto JovemRESUMO
Importance: Hidradenitis suppurativa (HS) leads to disfigurement and painful eruptions in terminal hair follicles of the intertriginous skin, mainly of axillary, genitofemoral, and perianal sites. It is associated with an excessive impairment of quality of life, psychiatric disorders, and sexual distress. Body image impairment has been linked to depression and anxiety and has been described for some dermatologic disorders but has not yet been investigated in patients with HS. Objectives: To investigate whether body image is diminished in patients with HS and whether disease severity, age at onset, disease duration, obesity, depression, and anxiety are linked to body image impairment. Design, Setting, and Participants: This 12-month (August 1, 2009, to August 31, 2010) case-control study with a prospective, observational, cross-sectional design recruited 47 consecutive patients with HS entering a tertiary care center and 45 healthy control individuals matched for age, sex, and body mass index (BMI). One patient and 4 controls failed to complete the questionnaire and were excluded from the evaluation. Data analysis was performed from December 1, 2013, to February 15, 2014. Main Outcomes and Measures: The Frankfurt Body Concept Scale (FKKS) and the Hospital Anxiety and Depression Scale (HADS) were given to patients and controls. Correlations among FKKS, HADS, and disease features were calculated. Results: Of the 46 patients and 41 controls included in the evaluation (mean [SD] age, 35.6 [1.6] years; 40 [46%] male and 47 [54%] female), HS significantly reduced body image (mean FKKS score, 234.2 [5.4] in patients and 276.9 [5.7] in controls; P < .001), even when controlled for BMI. A correlation was found for the extent of body image disruption and BMI (r = -0.589; P < .001), HADS-depression score (r = -0.619; P < .001), and HADS-anxiety score (r = -0.340; P = .03). No association was found for the body image score and the severity of HS, age at onset of disease, and duration of disease. The body contact subscale score was the only subscale score that was not different between patients with HS and controls. Conclusions and Relevance: Patients with HS have major body image impairment, which might lead to depression and anxiety, disorders that have been largely acknowledged in HS. This study identified another element of the psychosocial burden of patients with HS and reveals that body image could potentially be used as an outcome measure in future studies of HS.
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Imagem Corporal/psicologia , Hidradenite Supurativa/psicologia , Adulto , Ansiedade/etiologia , Índice de Massa Corporal , Estudos de Casos e Controles , Estudos Transversais , Depressão/etiologia , Feminino , Humanos , Masculino , Estudos Prospectivos , Escalas de Graduação Psiquiátrica , Inquéritos e QuestionáriosRESUMO
Mycosis fungoides (MF) progresses from patch to tumor stage by expansion of malignant T-cells that fail to be controlled by protective immune mechanisms. In this study, we focused on IL-32, a cytokine, highly expressed in MF lesions. Depending on the other cytokines (IL-4, GM-CSF) present during in vitro culture of healthy volunteers' monocytes, IL-32 increased the maturation of CD11c+ myeloid dendritic cells (mDC) and/or CD163+ macrophages, but IL-32 alone showed a clear ability to promote dendritic cell (DC) differentiation from monocytes. DCs matured by IL-32 had the phenotype of skin-resident DCs (CD1c+), but more importantly, also had high expression of indoleamine 2,3-dioxygenase. The presence of DCs with these markers was demonstrated in MF skin lesions. At a molecular level, indoleamine 2,3-dioxygenase messenger RNA (mRNA) levels in MF lesions were higher than those in healthy volunteers, and there was a high correlation between indoleamine 2,3-dioxygenase and IL-32 expression. In contrast, Foxp3 mRNA levels decreased from patch to tumor stage. Increasing expression of IL-10 across MF lesions was highly correlated with IL-32 and indoleamine 2,3-dioxygenase, but not with Foxp3 expression. Thus, IL-32 could contribute to progressive immune dysregulation in MF by directly fostering development of immunosuppressive mDC or macrophages, possibly in association with IL-10.
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Acne inversa (AI; also designated as hidradenitis suppurativa) is a chronic inflammatory disease with still unknown pathogenesis that affects the intertriginous skin of perianal, inguinal, and axillary sites. It leads to painful nodules, abscesses, and fistulas with malodorous secretion and is frequently associated with metabolic alterations. Here, we demonstrate that one of the most highly upregulated molecules in AI lesions is matrix metalloproteinase 8 (MMP8), an enzyme specialized in the degradation of extracellular matrix components and the HDL component apolipoprotein A-I. Granulocytes, which were present in AI lesions, secreted high amounts of MMP8 especially after TNF-α stimulation. Furthermore, activated fibroblasts but not keratinocytes were found to express MMP8. The high lesional MMP8 levels were accompanied by elevated blood levels that positively correlated with TNF-α blood levels and disease severity assessed by Sartorius score, especially with the number of regions with inflammatory nodules/abscesses and fistulas. Additionally, we found a negative correlation between blood MMP8 and HDL-cholesterol levels, suggesting a contributory role of MMP8 in metabolic alterations in AI. In summary, we demonstrate elevated MMP8 levels in AI lesions, suggest their role in skin destruction and metabolic alterations, and recommend the use of MMP8 as blood biomarker for AI disease activity assessment.
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Hidradenite Supurativa/sangue , Hidradenite Supurativa/metabolismo , Metaloproteinase 8 da Matriz/sangue , Metaloproteinase 8 da Matriz/metabolismo , Pele/patologia , Fator de Necrose Tumoral alfa/metabolismo , Adulto , Biomarcadores/metabolismo , Biópsia , HDL-Colesterol/metabolismo , Ensaio de Imunoadsorção Enzimática , Feminino , Fibroblastos/metabolismo , Granulócitos/citologia , Humanos , Imuno-Histoquímica , Queratinócitos/citologia , Masculino , Pessoa de Meia-IdadeRESUMO
The key role of RUNX3 in physiological T-cell differentiation has been extensively documented. However, information on its relevance for the development of human T-cell lymphomas or leukemias is scarce. Here, we show that alterations of RUNX3 by either heterozygous deletion or methylation of its distal promoter can be observed in the tumor cells of 15 of 21 (71%) patients suffering from Sézary syndrome, an aggressive variant of cutaneous T-cell lymphoma. As a consequence, mRNA levels of RUNX3/p46, the isoform controlled by the distal promoter, are significantly lower in Sézary syndrome tumor cells. Re-expression of RUNX3/p46 reduces cell viability and promotes apoptosis in a RUNX3/p46low cell line of cutaneous T-cell lymphoma. Based on this, we present evidence that RUNX3 can act as a tumor suppressor in a human T-cell malignancy and suggest that this effect is predominantly mediated through transcripts from its distal promoter, in particular RUNX3/p46.
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Subunidade alfa 3 de Fator de Ligação ao Core/genética , Regulação Neoplásica da Expressão Gênica , Linfoma Cutâneo de Células T/genética , RNA Mensageiro/genética , Apoptose , Western Blotting , Linhagem Celular Tumoral , Subunidade alfa 3 de Fator de Ligação ao Core/biossíntese , Metilação de DNA , Genes Supressores de Tumor , Humanos , Imuno-Histoquímica , Linfoma Cutâneo de Células T/metabolismo , Linfoma Cutâneo de Células T/patologia , Regiões Promotoras GenéticasRESUMO
The International League of Dermatological Societies (ILDS), a global, not-for-profit organization representing 157 dermatological societies worldwide, has identified the consequences of skin aging as one of the most important grand challenges in global skin health. Reduced functional capacity and increased susceptibility of the skin with development of dermatoses such as dry skin, itching, ulcers, dyspigmentation, wrinkles, fungal infections, as well as benign and malignant tumors are the most common skin conditions in aged populations worldwide. Environmental (e.g., pollution) and lifestyle factors (e.g., smoking, sunbed use) negatively affect skin health. In turn altered appearance, dry skin, chronic wounds, and other conditions decrease general health and reduce the likelihood for healthy and active aging. Preventive skin care includes primary, secondary, and tertiary interventions. Continuous sun protection from early childhood onward is most important, to avoid extrinsic skin damage and skin cancer. Exposure to irritants, allergens, or other molecules damaging the skin must be avoided or reduced to a minimum. Public health approaches are needed to implement preventive and basic skin care worldwide to reach high numbers of dermatological patients and care receivers. Education of primary caregivers and implementation of community dermatology are successful strategies in resource-poor countries. Besides specialist physicians, nurses and other health care professionals play important roles in preventing and managing age-related skin conditions in developing as well as in developed countries. Healthy skin across the life course leads to better mental and emotional health, positive impact on social engagement, and healthier, more active, and productive lives.
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Envelhecimento , Envelhecimento da Pele , Dermatopatias/epidemiologia , Idoso , Saúde Global , HumanosRESUMO
BACKGROUND: The formation of free radicals in human skin by solar ultraviolet radiation is considered to be the main reason for extrinsic skin aging. The antioxidants in human tissue represent an efficient protection system against the destructive action of these reactive free radicals. In this study, the parameters of the skin, epidermal thickness, stratum corneum moisture, elasticity and wrinkle volume, were determined before and after the treatment with antioxidant- or placebo-containing tablets and creams. METHODS: The study included 5 groups of 15 volunteers each, who were treated for 2 months with antioxidant-containing or placebo tablets, creams or a combination of antioxidant-containing tablets and cream. The skin parameters were measured at time point 0 and at week 8 utilizing ultrasound for the determination of epidermal thickness, a corneometer for stratum corneum moisture measurements, skin profilometry for quantifying the wrinkle volume and a cutometer for determining the elasticity. RESULTS: The verum cream had a positive influence on epidermal thickness, elasticity and skin moisture, but the verum tablets improved the epidermal thickness only. The combined application of verum tablets and creams led to a significant improvement of all investigated skin parameters, whereas the application of placebo tablets or cream did not influence any parameters. CONCLUSION: The topical and oral supplementation of antioxidants can be an instrument to improve several skin parameters and potentially counteract or decelerate the process of extrinsic skin aging.
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Antioxidantes/administração & dosagem , Absorção Cutânea/efeitos dos fármacos , Pele/efeitos dos fármacos , Administração Oral , Administração Tópica , Adulto , Idoso , Antioxidantes/farmacologia , Método Duplo-Cego , Elasticidade , Emulsões , Feminino , Humanos , Pessoa de Meia-Idade , Pele/anatomia & histologia , Pele/metabolismo , Envelhecimento da Pele/efeitos dos fármacos , Comprimidos , Água/metabolismo , Adulto JovemRESUMO
Immune surveillance of tumour cells is an important function of CD8 T lymphocytes, which has failed in cancer for reasons still unknown in many respect but mainly related to cellular processes in the tumour microenvironment. Applying imaging cycler microscopy to analyse the immune contexture in a human skin cancer we could identify and map 7,000 distinct cell surface-associated multi-protein assemblies. The resulting combinatorial geometry-based high-functional resolution led to discovery of a mechanism of T cell trapping in the epidermis, which involves SPIKE, a network of suprabasal keratinocyte projections piercing and interconnecting CD8 T cells. It appears initiated by clusters of infrabasal T and dendritic cells connected via cell projections across a fractured basal lamina to suprabasal keratinocytes and T lymphocytes.
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Neoplasias Cutâneas/imunologia , Neoplasias Cutâneas/metabolismo , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Microambiente Tumoral/imunologia , Antígenos de Superfície/metabolismo , Biomarcadores , Linfócitos T CD4-Positivos/imunologia , Linfócitos T CD4-Positivos/metabolismo , Linfócitos T CD4-Positivos/patologia , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Linfócitos T CD8-Positivos/patologia , Imunofluorescência , Humanos , Queratinócitos/metabolismo , Modelos Biológicos , Neoplasias Cutâneas/patologiaRESUMO
UNLABELLED: Psoriasis is considered as a model for chronic immune-mediated disorders. Th17-cells are pivotal players in those diseases. Recently, we demonstrated that Th17-cells produce interleukin (IL)-29 and that IL-29 is highly present in psoriatic lesions. Whether IL-29, with its action on epithelial cells and melanocytes, contributes to psoriasis pathogenesis, was unknown so far. Analysis of IL-29-treated human keratinocytes revealed induction of the chemokines CXCL10, CXCL11, and, to a much lesser extent, CXCL9. Unlike these CXCR3A ligands, known to attract Th1-, CD8(+), NK-, and Th1/Th17 transient cells, no influence was found on chemokines attracting other immune cell populations or on molecules modulating the CXCR3A/CXCR3A ligand interaction. CXCR3A ligand expression was also induced by IL-29 in melanocytes and in epidermis models and explanted skin. Regarding other psoriasis-relevant cytokines, interferon-γ and, less potently, tumor necrosis factor-α and IL-1ß shared and strengthened IL-29's capacity. Murine IL-29 counterpart injected into mouse skin provoked local CXCL10 and CXCL11 expression, T-cell infiltration, and, in consequence, skin swelling. The elevated IL-29 expression in psoriatic lesions was associated with upregulation of CXCR3A ligands compared to non-lesional skin of these patients and to the skin of healthy donors and atopic dermatitis patients, which lack IL-29 production. Importantly, neutralization of IL-29 reduced CXCR3A ligand levels in explant cultures of psoriatic lesions. Finally, elevated blood CXCL11 levels were found in psoriasis that might be useful for monitoring lesional activity of the IL-29 axis. In summary, the Th17-cytokine IL-29 induces specific chemokines and, in consequence, provokes skin infiltration of potentially pathogenic T-cells. KEY MESSAGES: IL-29 selectively induces CXCR3A-binding chemokines (CXCL9, CXCL10, CXCL11) in skin cells. Murine IL-29 counterpart induces skin T-cell infiltration and inflammation in mice. CXCR3A ligands are IL-29-dependently increased in lesional skin of psoriasis patients. CXCR3A ligand levels in psoriatic skin correlate with epidermal T-cell numbers. Increased blood CXCL11 levels in psoriasis may be a biomarker for local IL-29 action.
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Epitélio/imunologia , Epitélio/metabolismo , Interleucinas/metabolismo , Receptores CXCR3/biossíntese , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Adulto , Idoso , Animais , Estudos de Casos e Controles , Quimiocinas/metabolismo , Quimiotaxia , Expressão Gênica , Humanos , Interferons , Interleucinas/genética , Queratinócitos/metabolismo , Ligantes , Masculino , Camundongos , Pessoa de Meia-Idade , Psoríase/imunologia , Psoríase/metabolismo , Psoríase/patologia , Pele/imunologia , Pele/metabolismo , Pele/patologia , Adulto JovemRESUMO
Cutaneous T-cell lymphomas (CTCLs) form a heterogeneous group of non-Hodgkin's lymphomas characterized by only poor prognosis in advanced stage. Despite significant progress made in the identification of novel genes and pathways involved in the pathogenesis of cutaneous lymphoma, the therapeutic value of these findings has still to be proven. Here, we demonstrate by gene expression arrays that Aurora kinase A is one of the highly overexpressed genes of the serine/threonine kinase in CTCL. The finding was confirmed by quantitative reverse transcriptase-PCR, western blotting, and immunohistochemistry in CTCL cell lines and primary patient samples. Moreover, treatment with a specific Aurora kinase A inhibitor blocks cell proliferation by inducing cell cycle arrest in G2 phase, as well as apoptosis in CTCL cell lines. These data provide a promising rationale for using Aurora kinase A inhibition as a therapeutic modality of CTCL.
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Aurora Quinase A/genética , Regulação Neoplásica da Expressão Gênica , Linfoma Cutâneo de Células T/genética , Terapia de Alvo Molecular/métodos , Inibidores de Proteínas Quinases/farmacologia , Apoptose/efeitos dos fármacos , Biópsia por Agulha , Western Blotting , Estudos de Casos e Controles , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células , Feminino , Perfilação da Expressão Gênica , Humanos , Imuno-Histoquímica , Linfoma Cutâneo de Células T/patologia , Masculino , Reação em Cadeia da Polimerase em Tempo Real/métodos , Valores de Referência , Regulação para Cima/efeitos dos fármacosRESUMO
AIMS: Aggressive epidermotropic cutaneous CD8(+) lymphoma is currently afforded provisional status in the WHO classification of lymphomas. An EORTC Workshop was convened to describe in detail the features of this putative neoplasm and evaluate its nosological status with respect to other cutaneous CD8(+) lymphomas. METHODS AND RESULTS: Sixty-one CD8(+) cases were analysed at the workshop; clinical details, often with photographs, histological sections, immunohistochemical results, treatment and patient outcome were discussed and recorded. Eighteen cases had distinct features and conformed to the diagnosis of aggressive epidermotropic cutaneous CD8(+) lymphoma. The patients typically present with widespread plaques and tumours, often ulcerated and haemorrhagic, and histologically have striking pagetoid epidermotrophism. A CD8(+) /CD45RA(+) /CD45RO(-) /CD2(-) /CD5(-) /CD56(-) phenotype, with one or more cytotoxic markers, was found in seven of 18 patients, with a very similar phenotype in the remainder. The tumours seldom involve lymph nodes, but mucosal and central nervous system involvement are not uncommon. The prognosis is poor, with a median survival of 12 months. Examples of CD8(+) mycosis fungoides, lymphomatoid papulosis and Woringer-Kolopp disease presented the typical features well documented in the CD4(+) forms of those diseases. CONCLUSIONS: Aggressive epidermotropic cutaneous CD8(+) lymphoma is a distinct lymphoma that warrants inclusion as a distinct entity in future revisions of lymphoma classifications.
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Linfócitos T CD8-Positivos/imunologia , Linfoma Cutâneo de Células T/classificação , Linfoma Cutâneo de Células T/diagnóstico , Linfoma Cutâneo de Células T/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-IdadeRESUMO
PURPOSE: Primary cutaneous T-cell lymphomas (CTCL) are neoplastic disorders of skin-homing T cells. Affected skin areas show morphologic similarities with alterations in other T-cell-mediated dermatoses. Furthermore, as in atopic dermatitis but in contrast with psoriasis, patients with CTCL are frequently afflicted by cutaneous bacterial infections that support the survival of lymphoma cells. Our aim was to investigate the mechanisms of elevated susceptibility to cutaneous infections in patients with CTCL. EXPERIMENTAL DESIGN: Skin samples from CTCL, psoriasis, and atopic dermatitis patients were used to illuminate the antibacterial competence status and the presence of its modulating cytokines. For substantiation of findings, 3-dimensional epidermis models, isolated and in vitro generated Th-subpopulations, were applied. Parameters were analyzed via qPCR and IHC. RESULTS: CTCL lesions compared with psoriatic lesions presented an impaired upregulation of antibacterial proteins (ABPs), with levels even below those in atopic dermatitis. This was associated with a relative deficiency of the ABP-inducing cytokine IL-17 and a strong presence of the ABP-downregulating cytokine IL-13. The simultaneous presence of the Th17-cell cytokine IL-26 indicated that IL-17 deficiency in CTCL lesions results from functional deviation of Th17 cells. Accordingly, IL-17 but not IL-26 production by Th17 cells in vitro was inhibited by IL-4Rα ligand. Levels of other ABP inducers were comparable between CTCL and psoriasis lesions. The same was true about IL-22/TNF-α targets, including the keratinocyte hyper-regeneration marker K16 and the matrix-degrading enzyme MMP1. CONCLUSION: Our results suggest that the cutaneous bacterial infections in CTCL are caused by impaired ABP induction as consequence of Th2-mediated biased Th17-cell function.