Role of chemokines and the corresponding receptors in vitiligo: A pilot study

To determine the levels and sources of chemokines in the serum and epidermis of vitiligo patients, we examined 80 active patients, 80 stable patients and 40 healthy controls. First, the serum levels of candidate chemokines were measured by Luminex assay, and levels of CCR5, CXCR1 and CXCR3 were measured in peripheral mononuclear cells (PMBC) by flow cytometry. Then, the local epidermis levels of elevated chemokines in vitiligo were tested by Luminex. Finally, the mRNA and protein expression levels of elevated chemokines in HaCaT cells stimulated with interferon (IFN)‐γ or tumor necrosis factor (TNF)‐α were tested by quantitative real‐time polymerase chain reaction and Luminex. The serum levels of CCL5, CXCL8 and CXCL10 in active vitiligo were significantly elevated compared with those in stable vitiligo patients. Furthermore, the levels of CCL3 and CCL4 had weak and positive correlations with the Vitiligo Area Scoring Index. In the peripheral blood of active vitiligo patients, the percentages of CD3⁺CD8⁺CCR5⁺ and CD3⁺CD8⁺CXCR3⁺ T cells were significantly increased compared with those in stable vitiligo and healthy controls. In the epidermis of lesions, the expression levels of CCL5 and CXCL10 in active vitiligo were significantly increased. In addition, the mRNA and protein levels of CCL5, CXCL8 and CXCL10 were significantly elevated in HaCaT cells after stimulation with TNF‐α or IFN‐γ. The CCR5/CCL5 and CXCR3/CXCL10 axes may play an important role in the progression and maintenance of vitiligo. Moreover, keratinocytes stimulated with TNF‐α and IFN‐γ may be a primary source of CCL5 and CXCL10.     

Reduction of skin-homing cytotoxic T cells (CD8+ -CLA+) in patients with vitiligo

Background: Vitiligo is a frequently acquired, hereditary disease, characterized by achromic macules due to the absence of melanocytes. In contrast with earlier studies, in which the main pathogenic role was attributed to anti‐melanocyte antibodies, recent papers have emphasized a role for CD8⁺ cytotoxic T lymphocytes in melanocyte destruction. Fifteen percent of peripheral T cell express cutaneous lymphocyte‐associated antigen (CLA), responsible for skin‐homing T cell. Phototherapy is used to treat patients with generalized vitiligo and it has been shown to interfere with CLA⁺ T cells in other skin diseases. Objective: To describe peripheral blood T cell subpopulations' frequency and ability to express the skin‐homing molecule (CLA) in patients with non‐segmental vitiligo, before and after photochemotherapy (PUVA). Patients and Methods: Twenty‐two patients with generalized and active spreading vitiligo were submitted to 30 PUVA‐8MOP sessions. Lymphocyte immunophenotyping was performed by flow cytometry using anti‐CD3, anti‐CD8 and anti‐CLA monoclonal antibodies. Fifteen healthy volunteers, sex‐ and age‐matched, were included as a control group. Results: CD8⁺–CLA⁺ T cells were significantly reduced in number in untreated vitiligo patients (P=0.008) when compared with control individuals, albeit with a more intense CLA expression (P=0.028). These findings were not altered after PUVA. No significant difference was noticed in CD4/CD8 ratios nor in CD4–CLA⁺ T cell numbers between vitiligo patients and controls, both before and after PUVA. Conclusions: CD8–CLA⁺ T cells are reduced in peripheral blood of patients with non‐segmental vitiligo. This finding may be related to the previously reported increase of CD8⁺ cells in both lesions and perilesional skin of these patients.     

Role of macrophage infiltration in successful repigmentation in a new periphery‐spreading vitiligo lesion in a male Japanese patient

Vitiligo is an acquired disorder in which depigmented macules result from mostly autoimmune loss of melanocytes. The initiating process in vitiligo has still been uncertain. Here, we report the case of a 19‐year‐old man with undetermined/unclassified vitiligo with a new periphery‐spreading vitiligo lesion on the right dorsal hand after rigorous sun exposure. Histopathological evaluation showed noticeable infiltration of CD68⁺ macrophages, moderate infiltration of CD3⁺ T cells, little infiltration of CD8⁺ T cells and CD11c⁺ myeloid dendritic cells, HMB45/CD11c double‐positive cells, and Melan‐A/MART1⁺ deposits in the dermis. We surmised that melanocyte‐derived deposits were mostly phagocytosed by CD68⁺ macrophages and were faintly phagocytosed by CD11c⁺ myeloid dendritic cells, referring distribution of CD68⁺ mononuclear cells and melanocyte biomarkers. Complete repigmentation was achieved following topical application of hydrocortisone butyrate propionate 0.1% ointment. We summarize that prompt clearance of debris by macrophages would be essential to an excellent prognosis of complete repigmentation.     

Impaired T‐cell‐dependent protection against Leishmania major infection in HIV‐positive patients is associated with worsened disease outcome

Cutaneous leishmaniasis (CL) patients coinfected with HIV are known to show a more severe, prolonged course of disease; the immunological basis is not known. We now assessed clinical features, sera and skin biopsies of HIV⁺ and HIV^? patients with CL to identify drivers of increased susceptibility to Leishmania. CL lesion numbers, surface, and healing duration were significantly increased in HIV⁺ as compared to HIV^? patients (2.5, 14 and >4‐fold, respectively). Patients with HIV infection exhibited lower serum Leishmania‐specific IgG levels and decreased IL‐6 and IL‐8. Most importantly, dramatically decreased numbers of CD4⁺ T cells (approximately eightfold), but not CD8⁺ cells, together with fewer CXCR3⁺ Th1 cells, fewer Foxp3⁺ effector/regulatory T cells, and reduced levels of IFN‐γ expression were found in lesional skin. Our findings suggest that compromised CD4⁺ T‐cell responses may be responsible for worsened disease outcome leading to defects in parasite elimination in the absence of sufficient numbers of IFN‐γ‐producing Th1 cells.     

Evaluation of activatory and inhibitory natural killer cell receptors in non-segmental vitiligo: a flow cytometric study

Background Recent observations established the role of altered cellular immunity and autoimmune hypothesis in the pathogenesis of vitiligo. There have been several reports discussing T‐cell and natural killer (NK) cell populations, but NK cell receptors were not evaluated in vitiligo. Objective The purpose of this investigation was to assess the role of T and NK cells as well as activatory and inhibitory NK cell receptor alterations in the pathogenesis of vitiligo and whether any aberrations were correlated with clinical findings of the disease. Patients/methods Fifty‐three patients with non‐segmental vitiligo and 45 age‐ and sex‐matched healthy controls were enrolled in the study. The percentages of lymphocytes, granulocytes, monocytes and CD3, CD4, CD8, CD14, CD16, CD56, CD45, CD45RA, CD54RO, CD28, CD80, CD94, CD158a, KIR3DL‐1 receptors as well as CD94, CD158a, KIR3DL‐1 receptors on CD16⁺ cells were detected by using flow cytometry. The patient and control groups were compared in terms of the results of flow cytometric analysis, and the results were assessed regarding the type and activity of vitiligo. Results The percentages of CD16⁺CD56⁺, CD3⁺CD16⁺CD56⁺, CD8⁺ and CD45RO⁺ cells were significantly increased in vitiligo group compared with the controls. No difference was detected between the patients and control groups in percentages of CD3⁺, CD4⁺, CD3^?CD16⁺CD56⁺, CD28⁺, CD45⁺, CD45RA⁺, CD94⁺, CD158a⁺ and KIR3DL‐1⁺ cells. The percentage of CD16⁺CD158a⁺ cells was significantly decreased in a randomized selected group of vitiligo patients. There were no differences in percentage expression of studied cell surface antigens between patients in the active or stable period. CD3⁺ cells were significantly increased in generalized form, and CD45RO⁺ cells were significantly increased in acral/acrofacial form when compared with the other types of vitiligo. Conclusions These results indicate further evidence for T and NK cell abnormalities in non‐segmental vitiligo. The present data show that NK cell activation may be responsible in the pathogenesis of vitiligo in conformity with decreased inhibitory and increased activatory NK cell receptors.     

Expression of T‐cell immunoglobulin and immunoreceptor tyrosine‐based inhibitory motif domain on CD4+ T cells in patients with atopic dermatitis

The T‐cell immunoglobulin and immunoreceptor tyrosine‐based inhibitory motif domain (TIGIT) is a co‐inhibitory receptor mainly expressed on T cells. Although TIGIT plays an important role in various autoimmune diseases, its role in atopic dermatitis (AD) remains unclear. In this study, we examined the expression levels of TIGIT and their association with clinical features in patients with AD. TIGIT expression on CD4⁺ T cells, central memory T cells, effector memory T cells and regulatory T cells was determined by flow cytometry. CD4⁺ T cells exhibited enhanced TIGIT expression in patients with AD compared with healthy individuals. In particular, effector memory T cells and regulatory T cells, but not central memory T cells, exhibited higher TIGIT expression in patients with AD than in healthy individuals. The frequency of TIGIT⁺ cells among CD4⁺ T cells was significantly increased in patients with mild AD compared with healthy individuals, while decreased in patients with severe AD. Consistently, the frequency of TIGIT⁺ cells among CD4⁺ T cells was negatively correlated with both serum thymus and activation‐regulated chemokine levels and immunoglobulin E levels in patients with AD. Furthermore, TIGIT expression on CD4⁺ T cells inhibited cell proliferation in patients with AD. These results suggest that TIGIT expression on CD4⁺ T cells in patients with AD may be increased to suppress chronic cutaneous inflammation. Moreover, TIGIT expression may be impaired in a subset of patients with AD, leading to a deterioration of skin inflammation. Our study may provide new insight into a TIGIT pathway‐based therapeutic approach for AD.     

Human T‐lymphotropic virus 1 (HTLV‐1)‐associated lichenoid dermatitis induced by CD8+ T cells in HTLV‐1 carrier,HTLV‐1‐associated myelopathy/tropical spastic paraparesis and adult T‐cell leukemia/lymphoma

Human T‐lymphotropic virus type 1 (HTLV‐1) induces adult T‐cell leukemia/lymphoma (ATLL), HTLV‐1‐associated myelopathy/tropical spastic paraparesis (HAM/TSP) and carrier. ATLL is a mature CD4⁺CD25⁺CCR4⁺ T‐cell neoplasm, and approximately half of patients have direct skin involvement manifesting patch, plaque, tumor, multiple papules, erythroderma and purpura. However, there exist secondary eruptions without tumor cell infiltration in patients with ATLL or HAM/TSP and carriers of HTLV‐1. To clarify the presence of reactive skin eruptions in HTLV‐1‐infected individuals, we reviewed our patients with HTLV‐1‐associated diseases. In 2002–2012, we saw 50 ATLL or HAM/TSP patients and HTLV‐1 carriers presenting with skin lesions. We retrospectively selected cases that histologically showed lichenoid tissue reactions with predominant infiltration of CD8⁺ T cells, but not CD4⁺ tumor cells. The cases included erythroderma (HTLV‐1 carrier), lichen planus (HTLV‐1 carrier), alopecia areata (HAM/TSP), chronic actinic dermatitis (HTLV‐1 carrier to acute ATLL conversion) and discoid lupus erythematosus (smoldering ATLL). They were graft‐versus‐host disease‐like, major secondary lesions and seen in HTLV‐1 carriers and patients with HAM/TSP and smoldering ATLL. We coin the term HTLV‐1‐associated lichenoid dermatitis (HALD) to encompass the conditions. HALD may occur in association with the elevated immunity toward HTLV‐1‐infected CD4⁺ T cells, thus sharing the pathogenetic role of cytotoxic T cells with HAM/TSP.     

Attenuation of contact hypersensitivity by cell‐permeable heat shock protein 70 in BALB/c mouse model

 In contact hypersensitivity (CHS), multiple cells, inflammatory mediators and cytokines are known to be involved in the regulation of the immune response. Previously, we revealed the reactive oxygen species generation by 2, 4, 6‐trinitrobenzene sulphonic acid (TNBS) in vivo, followed by heat shock protein 70 (Hsp70) carbonylation and the exogenous antioxidant role of cell‐permeable Hsp70. Here, we demonstrate the role of Hsp70 using cell‐permeable Hsp70 in the mouse CHS model. Pretreatment of cell‐permeable Hsp70: (i) suppressed ear swelling; (ii) down‐regulated phosphorylated p38, but up‐regulated phosphorylated extracellular signal‐regulated kinase; (iii) increased population of CD4⁺CD25⁺Foxp3⁺ T cells; (iv) decreased secretion of tumor necrosis factor‐α (TNF‐α), IL‐12, interferon‐γ and IL‐2 and (v) but up‐regulated IL‐4 and transforming growth factor beta (TGF‐β) in the lymph nodes. In conclusion, cell‐permeable Hsp70 attenuates CHS through modulation of MAPK pathway and regulation of Th1, Th2 and regulatory T cells.     

Evidence for a regulatory loop between IFN‐γ and IL‐33 in skin inflammation

Interleukin‐33 has recently gained much attention due to its role in allergic responses. It has been shown to amplify Th2 responses and to act as a damage‐associated molecular pattern. IL‐33 acts on a broad range of cells and has been proposed to link innate and adaptive features of allergic responses. It was the aim of this study to investigate this property of IL‐33 in the inflammatory response characterising atopic dermatitis (AD). We have analysed the response of skin‐resident cells derived from patients with AD and healthy donors with regard to the expression of IL‐33 and its receptor ST2. The functional impact of IL‐33 on CD4+ T cells was investigated. Keratinocytes and dermal fibroblasts clearly differ in their regulation of IL‐33. In fibroblasts, the concerted action of TNF‐α and IL‐1β was the strongest inducer, whereas IFN‐γ is clearly the key molecule that upregulates IL‐33 in keratinocytes with a more pronounced response of cells derived from patients with AD. Keratinocytes from patients with AD showed a markedly higher constitutive expression level of surface ST2. CD4+ T cells respond to IL‐33. Unexpectedly, IL‐33 failed to induce a significant secretion of IL‐5 or IL‐13. By contrast, high amounts of IFN‐γ were detectable if IL‐33 was added to the T‐cell receptor‐stimulated cells or in combination with IL‐12. These results suggest that IL‐33 and IFN‐γ are closely interlinked in epidermal AD inflammation. IFN‐γ induces IL‐33 in keratinocytes and IL‐33 acts on activated T cells to further increase the release of IFN‐γ, therefore contributing to drive skin inflammation towards chronic responses.     

Papuloerythroderma‐like cutaneous involvement of a CD62L− subclone of T‐cell prolymphocytic leukemia

We report the case of an 88‐year‐old Japanese man with erythrodermic involvement of T‐cell prolymphocytic leukemia (T‐PLL). He had a history of pharyngeal diffuse large B‐cell lymphoma successfully treated with polychemotherapy including cyclophosphamide and epirubicin, 6 years before the current illness. He presented with numerous reddish, coalescing, flat‐topped papules on the trunk and extremities, sparing the skin folds of the abdomen, the features of which mimicked those of papuloerythroderma. Immunohistochemistry showed perivascular and epidermotropic infiltration of CD3⁺ CD4⁺ T cells in the cutaneous lesion. However, flow cytometric analysis revealed that the skin infiltrating T cells were negative for surface CD4, and that CD3⁺ CD4^? CD8^? cells made up 92% of the T‐cell fraction of peripheral blood. The circulating atypical T cells had a round or oval nucleus and prominent nucleoli, and the deletion of chromosomes 6q, 13 and 17. These cytological profiles were consistent with those of T‐PLL and distinct from those of Sézary cells. The same T‐cell clone was detected in the cutaneous lesion and peripheral blood, but the expression of CD62L was absent in the skin infiltrates and present in the circulating cells. No specific mutation was detected in STAT3 or STAT5B. Although low‐dose oral etoposide had a beneficial effect on the skin rash, a fatal crisis of marked leukocytosis (169 × 10³/μL) occurred 19 months after the illness onset. CD62L‐leukemic cells of T‐PLL may infiltrate the skin to form papuloerythroderma‐like cutaneous lesions.     

Role of the subgroups of T,B, natural killer lymphocyte and serum levels of interleukin‐15, interleukin‐21 and immunoglobulin E in the pathogenesis of urticaria

The immunological characterization in the pathogenesis of urticaria, mainly regarding cytokine profile, needs more investigation. In this study, subgroups of the T, B and natural killer (NK) lymphocyte from peripheral blood and serum levels of interleukin (IL)‐15, IL‐21 and immunoglobulin (Ig)E were examined in patients with acute urticaria (AU) and chronic urticaria (CU). Moreover, symptom scores and course of the patients were assessed. The percentage of NK cells and the ratio of CD4⁺/CD8⁺ increased, however, CD8⁺ decreased in CU compared to controls (P < 0.01). But no significant changes of T, B and NK lymphocyte were found in AU. IL‐15 and IL‐21 significantly decreased in AU and CU, but IgE increased. CU with a positive autologous serum skin test were more likely to be associated with longer course and higher CD3⁺, B cells and IL‐21, and lower IgE (P < 0.01). Weak negative correlations were demonstrated between CD3⁺, CD8⁺ and scores in CU (r = ?0.23, ?0.25, P < 0.05). Significant correlations were found between B cells and scores and course in CU (r = 0.49, 0.65, P < 0.01). Moreover, a significant correlation was found between IL‐21 and IgE (r = 0.42, P < 0.01) in CU. But no significant correlations were found in AU. Our findings supported the concept that both humoral immunity and cellular immunity dysregulation in the pathogenesis of urticaria – mainly related to the decrease of the serum levels of IL‐15 and IL‐21 – may induce the increasing expression of IgE produced by B cells.     

CD4+ T cells producing interleukin (IL)‐17, IL‐22 and interferon‐γ are major effector T cells in nickel allergy

Background It has been suggested that interleukin (IL)‐17 and IL‐22 play important roles in the elicitation of human allergic contact dermatitis; however, the frequencies of T cell subtypes producing IL‐17 and IL‐22 in human allergic contact dermatitis are unknown. Objectives To determine the frequencies of CD4⁺, CD8⁺ and γδ T cells producing IL‐17, IL‐22 and interferon (IFN)‐γ in the blood and skin from nickel‐allergic patients. Patients/materials/methods Blood samples were collected from 14 patients and 17 controls, and analysed by flow cytometry. Biopsies were taken from 5 patients and 6 controls, and analysed by immunohistochemistry and flow cytometry of skin lymphocytes. Results We found an increased frequency of γδ T cells in the blood, but no differences in the distribution of cytokine‐producing CLA⁺ T cell subtypes in nickel‐allergic patients as compared with controls. In nickel‐allergic patients, there was massive cellular infiltration dominated by CD4⁺ T cells producing IL‐17, IL‐22 and IFN‐γ in nickel‐challenged skin but not in vehicle‐challenged skin. Conclusion CD4⁺ T cells producing IL‐17, IL‐22 and IFN‐γ are important effector cells in the eczematous reactions of nickel‐induced allergic contact dermatitis in humans.     

Case of primary cutaneous peripheral T‐cell lymphoma,not otherwise specified,with characteristics of follicular helper T cells

We report a case of an 88‐year‐old woman with a decalvant, erythematous, ulcerated tumor extending from the right temporal to occipital region. Histopathological analysis revealed a dense infiltration of medium‐to‐large‐sized atypical cells throughout the entire dermis. The result of immunohistochemical analysis showed that the infiltrating T cells expressed programmed death‐1 (PD‐1), Bcl‐6 and CXCL13. Flow cytometry analysis showed that CD4⁺ PD‐1^hi T cells also expressed CD10, inducible T‐cell co‐stimulator and CXCR5. On the basis of the clinical appearance and the histopathological findings, we diagnosed the patient with primary cutaneous peripheral T‐cell lymphoma, not otherwise specified. Recently, the concept of primary cutaneous follicular helper T (TFH)‐cell lymphoma was proposed, and in this case, tumor cells clearly expressed TFH‐cell markers. Therefore, we considered this case to be a variant of the entity. Although this entity is still provisional, this case supports the new concept.     

Effective induction of melanoma‐antigen‐specific CD8+ T cells via Vγ9γδT cell expansion by CD56high+ Interferon‐α‐induced dendritic cells

Dendritic cells (DCs) can be differentiated from CD14⁺ monocytes in the presence of interferon‐α (IFNα) and granulocyte/macrophage‐colony stimulating factor (GM‐CSF) in vitro and are known as IFN‐DCs. Circulating blood CD56⁺ cells expressing high levels of CD14, HLA‐DR and CD86 have been shown to spontaneously differentiate into DC‐like cells in vitro after their isolation from blood. We show here that IFN‐DCs expressing high levels of CD56 (hereafter, CD56^high+ IFN‐DCs) can be differentiated in vitro from monocytes obtained as adherent cells from healthy donors and patients with metastatic melanoma. These cells expressed high levels of CD14, HLA‐DR and CD86 and possessed many pseudopodia. These CD56^high+ IFN‐DCs may be an in vitro counterpart of the circulating CD56⁺ CD14⁺ CD86⁺ HLA‐DR⁺ cells in blood. Conventional mature DCs differentiated from monocytes as adherent cells in the presence of GM‐CSF, IL‐4 and TNF‐α (hereafter, mIL‐4DCs) did not express CD56 or CD14. In contrast to mIL‐4DCs, the CD56^high+ IFN‐DCs exhibited a stronger capacity to stimulate autologous CD56⁺ Vγ9γδT cells highly producing IFNγ in the presence of zoledronate and IL‐2. The CD56^high+ IFN‐DCs possessing HLA‐A*0201 effectively induced Mart‐1‐modified melanoma peptide (A27L)‐specific CD8⁺ T cells through preferential expansion of CD56⁺ Vγ9γδT cells in the presence of A27L, zoledronate and IL‐2. Vaccination with CD56^high+ IFN‐DCs copulsed with tumor antigens and zoledronate may orchestrate the induction of various CD56⁺ immune cells possessing high effector functions, resulting in strong immunological responses against tumor cells. This study may be relevant to the design of future clinical trials of CD56^high+ IFN‐DCs‐based immunotherapies for patients with melanoma.     

Increase of interleukin‐10‐producing B cells associated with long‐term remission after i.v. immunoglobulin treatment for pemphigus

We present a refractory case of pemphigus vulgaris that achieved long‐term remission after i.v. immunoglobulin treatment (IVIG). We evaluated the fluctuation of circulating interleukin‐10‐producing B cells (B10 cells) during the course in our case and other three patients with pemphigus treated with IVIG without clinical remission. B10 cells were observed predominantly in CD1d^–, CD5^–, CD9^– and CD27⁺ populations among CD19⁺ cells in healthy controls, as well as in patients with pemphigus. The frequency of B10 cells among CD19⁺ cells increased in our case, but not in the other three patients without clinical remission, which leads to speculation on the association between the increase of B10 cells and the achievement of long‐term remission after IVIG treatment.     

Differential expression analysis of miRNA in peripheral blood mononuclear cells of patients with non‐segmental vitiligo

Vitiligo is a common depigmentary skin disease that may follow a pattern of multifactorial inheritance. The essential factors of its immunopathogenesis is thought to be the selective destruction of melanocytes. As a new class of microregulators of gene expression, miRNA have been reported to play vital roles in autoimmune diseases, metabolic diseases and cancer. This study sought to characterize the different miRNA expression pattern in the peripheral blood mononuclear cells (PBMC) of patients with non‐segmental vitiligo (NSV) and healthy individuals and to examine their direct responses to thymosin α1 (Tα1) treatment. The miRNA expression profile in the PBMC of patients with NSV was analyzed using Exiqon's miRCURY LNA microRNA Array. The differentially expressed miRNA were validated by real‐time quantitative polymerase chain reaction. We found that the expression levels of miR‐224‐3p and miR‐4712‐3p were upregulated, and miR‐3940‐5p was downregulated in the PBMC. The common clinical immune modulator Tα1 changed the miRNA expression profile. Our analysis showed that differentially expressed miRNA were associated with the mechanism of immune imbalance of vitiligo and that Tα1 could play an important role in changing the expression of these miRNA in the PBMC of patients with NSV. This study provided further evidence that miRNA may serve as novel drug targets for vitiligo therapeutic evaluation.     

Characterization of the T cell response in allergic contact dermatitis caused by corticosteroids

Background Delayed allergic hypersensitivity reactions have classically been described as type IV reactions, which are caused by T cells; however, the respective roles of CD4⁺ and CD8⁺ cells are yet to be defined. A central role for CD8⁺ cytotoxic T cells as effector cells has been suggested. Objectives To determine the type of T cell involved in corticosteroid allergy. Methods We analysed the kinetics of T cell recruitment and the cytokine production profile in positive patch tests of 27 corticosteroid‐sensitized patients, as compared with control sites and control subjects. Skin biopsies, collected at 8, 24 and 48 hr following drug application, were embedded in paraffin for histological and immunohistological staining, and, in some cases, also deep‐frozen for gene expression analyses. Results CD3⁺ T cells were rapidly recruited in concert with the positivity of the patch test sites. High levels of interleukin (IL)‐4, IL‐5 and, to a lesser extent, interferon‐γ suggested that both Th2 and Th1 cytokines were implicated. IL‐4 was also produced by γδ T cell receptor (TCR) lymphocytes. Conclusions This study showed that, in allergic contact dermatitis caused by corticosteroids, the inflammatory infiltrate is composed of CD3⁺ T cells with a predominant Th2 cytokine profile, among which IL‐4 is also produced by γδ TCR lymphocytes.     

Oligosaccharide modification by N‐acetylglucosaminyltransferase‐V in macrophages are involved in pathogenesis of bleomycin‐induced scleroderma

Oligosaccharide modification by N‐acetylglucosaminyltransferase‐V (GnT‐V), which catalyses the formation of β1,6 GlcNAc (N‐acetylglucosamine) branches on N‐glycans, is associated with various pathologies, such as cancer metastasis, multiple sclerosis and liver fibrosis. In this study, we demonstrated the involvement of GnT‐V in the pathophysiology of scleroderma. High expression of GnT‐V was observed in infiltrating cells in skin section samples from systemic and localized patients with scleroderma. Most of the infiltrating cells were T cells and macrophages, most of which were CD163⁺ M2 macrophages. To determine the role of GnT‐V in scleroderma, we next investigated skin sclerosis in GnT‐V knockout (MGAT5^?/?) mice. Expression of GnT‐V was also elevated in bleomycin (BLM)‐injected sclerotic skin, and MGAT5^?/? mice were resistant to BLM‐induced skin sclerosis with reduced collagen type 1 α1 content, suggesting the biological significance of GnT‐V in skin sclerosis. Furthermore, the number of CD163⁺ M2 macrophages and CD3‐positive T cells in BLM‐induced skin sclerosis was significantly fewer in MGAT5^?/? mice. In bone marrow‐derived macrophages (BMDMs), IL‐4‐induced expressions of Fizz1 and Ym1 were significantly reduced in MGAT5^?/? mice‐derived BMDMs. Taken together, these results suggest the induction of GnT‐V in skin sclerosis progression is possibly dependent on increased numbers of M2 macrophages in the skin, which are important for tissue fibrosis and remodelling.