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Systemic sclerosis (SSc) is an autoimmune disease characterized by vasculopathy, aberrant immune activation, and extensive tissue fibrosis of the skin and internal organs. Because of the complicated nature of its pathogenesis, the underlying mechanisms of SSc remain incompletely understood. Angiogenic factor with a G‐patch domain and a Forkhead‐associated domain 1 (AGGF1) is a critical factor in angiogenesis expressed on vascular endothelial cells, associated with inflammatory and fibrotic responses. To elucidate the possible implication of AGGF1 in SSc pathogenesis, we investigated the association between serum AGGF1 levels and clinical manifestations in SSc patients. We conducted a cross‐sectional analysis of AGGF1 levels in sera from 60 SSc patients and 19 healthy controls with enzyme‐linked immunosorbent assay. Serum AGGF1 levels in SSc patients were significantly higher than those in healthy individuals. In particular, diffuse cutaneous SSc patients with shorter disease duration had higher levels compared to those with longer disease duration and limited cutaneous SSc patients. Patients with higher serum AGGF1 levels had a higher incidence of digital ulcers, higher modified Rodnan Skin Scores (mRSS), elevated serum Krebs von den Lungen‐6 (KL‐6) levels, C‐reactive protein levels, and right ventricular systolic pressures (RVSP) on the echocardiogram, whereas they had reduced percentage of vital capacity (%VC) and percentage of diffusing capacity of the lungs for carbon monoxide (%DLCO) in pulmonary functional tests. In line, serum AGGF1 levels were significantly correlated with mRSS, serum KL‐6 and surfactant protein D levels, RVSP, and %DLCO. These results uncovered notable correlations between serum AGGF1 levels and key cutaneous and vascular involvements in SSc, suggesting potential roles of AGGF1 in SSc pathogenesis. [ABSTRACT FROM AUTHOR]

This article presents a case report of a 38-year-old female with nodular scleroderma (NS) successfully treated with tocilizumab (TCZ). NS is a rare variant of scleroderma characterized by multiple sclerotic nodules and keloidal plaques. The patient had cutaneous sclerosis, joint stiffness, and difficulty breathing. After treatment with TCZ, the nodules and plaques softened and flattened, and the patient reported an improvement in skin tightness. The article discusses the immunological profiles of NS and its similarities to morphea, as well as the potential triggers for NS, such as pregnancy and delivery. The treatment of NS is often challenging, but TCZ has shown promise in alleviating cutaneous fibrosis. Further research is needed to understand the underlying pathophysiology of NS. [Extracted from the article]

Palmoplantar pustulosis (PPP) is a chronic skin inflammatory disease characterized by sterile pustules on the palms and soles. Pustulotic arthro‐osteitis (PAO) is a major comorbidity of PPP, frequently affecting the anterior chest wall. PPP and PAO are thought to be closely associated with focal infection. We report a female in her 40s who developed pustules on her palms and soles with tenderness of both sternoclavicular and left sacroiliac joints, which were not improved with non‐steroidal anti‐inflammatory drugs. Of note, she showed a great response to amoxicillin, resulting in the almost complete resolution of her skin lesions and arthralgia. We also reviewed previous reports to learn more about the potential therapeutic options of antibiotics for PAO. [ABSTRACT FROM AUTHOR]

Objectives: Graft‐versus‐host disease (GVHD) is an important complication of bone marrow transplantation. Recent reports suggest the significance of T‐cell subsets (Th1, Th17, and cytotoxic CD8+ T cells) as well as CD163+ macrophages in the development of cutaneous GVHD. CD163+ macrophages produce various chemokines to establish the immunological microenvironment following stimulation by stromal factors in lesional skin. Thus, the purpose of this study is to determine the main source of IFN‐inducible chemokines in the lesional skin of GVHD. Methods: We employed immunohistochemical (IHC) staining for CD163 as well as interferon (IFN)‐inducible chemokines (CXCL9, CXCL10, CXCL11) to determine if the main source of IFN‐inducible chemokines in the lesional skin of GVHD was CD163+ macrophages. Moreover, we investigated the possible cytokine profiles of lesional skin in GVHD by evaluating phospho‐signal transducer and activator of transcription (pSTAT) expression in epidermal keratinocytes. Results: Immunohistochemical staining of serial sections for CD163 revealed that CXCL9‐expressing cells, CXCL10‐expressing cells, and CXCL11‐expressing cells were detected in adjacent to CD163+ TAMs in the dermis. In contrast, there were no CCL17‐expressing cells or CCL22‐expressing cells in the dermis. The nuclei of epidermal keratinocytes in GVHD expressed pSTAT1, pSTAT3, and pSTAT5B. Conclusions: The chemokine expression patterns on CD163+ macrophages matched the expected phosphorylation pattern of epidermal STATs. Our present study suggested that CD163 + macrophages may be a therapeutic target in GVHD. The significance of T‐cell subsets (Th1, Th17, and cytotoxic CD8+ T cells) as well as CD163+ macrophages in the development of cutaneous GVHD. ·IHC staining revealed that CXCL9‐expressing cells, CXCL10‐expressing cells, and CXCL11‐expressing cells were detected in adjacent to CD163+ TAMs in the dermis. ·The chemokine expression patterns on CD163+ macrophages matched the expected phosphorylation pattern of epidermal STATs. [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic inflammatory skin disease with a high prevalence of cardiovascular disease (CVD), obesity, dyslipidemia, hypertension, diabetes mellitus, and metabolic syndrome. Among them, CVD is the most common cause of morbidity and mortality in psoriasis patients. Since CVD is associated with considerable morbidity and mortality, primary care clinicians are increasingly committed to reducing the risk of CVD in patients with psoriasis. Biologics targeting TNF-α, IL-12/23, and IL-17 are systemic therapies that can dramatically improve the condition of psoriasis. Recent studies have reported that these inflammatory cytokine signals may promote atherosclerosis, suggesting that biologics might be effective for improving psoriasis as well as reducing the risk of CVD. Here, we reviewed cardiovascular risk in psoriasis patients, the association between psoriatic inflammation and atherosclerosis, and the efficacy of biologics for reducing the risk of cardiovascular diseases. [ABSTRACT FROM AUTHOR]

Palmoplantar pustulosis (PPP) is a chronic skin inflammatory disease in which blisters and pustules repeatedly develop on palms and soles. PPP is often refractory to topical therapy, oral therapy, phototherapy, and biologics that are usually applied for PPP. We report a patient with PPP improved by vedolizumab (anti-α4β7 integrin antibody) treatment for ulcerative colitis, suggesting the possibility of a new molecular target for PPP therapy. [ABSTRACT FROM AUTHOR]

An active form of cathelicidin antimicrobial peptide, LL-37, has immunomodulatory and stimulatory effects, though the specific pathways are not clear. The purpose of this study was to identify the cellular pathways by which LL-37 amplifies the inflammation induced by damage-associated molecular patterns (DAMPs). We performed DNA microarray, reverse transcription polymerase chain reaction, immunoblotting, and proximity ligation assays using cultured keratinocytes treated with LL-37 and/or the DAMP poly(I:C), a synthetic double-stranded RNA. In contrast to the combination of LL-37 and poly(I:C), LL-37 alone induced genes related to biological metabolic processes such as VEGFA and PTGS2 (COX-2). Inhibition of FPR2, a known receptor for cathelicidin, partially suppressed the induction of VEGFA and PTGS2. Importantly, VEGFA and PTGS2 induced by LL-37 alone were diminished by the knockdown of scavenger receptors including SCARB1 (SR-B1), OLR1 (SR-E1), and AGER (SR-J1). Moreover, LL-37 alone, as well as the combination of LL-37 and poly(I:C), showed proximity to the scavenger receptors, indicating that LL-37 acts via scavenger receptors and intermediates between them and poly(I:C). These results showed that the broad function of cathelicidin is generally dependent on scavenger receptors. Therefore, inhibitors of scavenger receptors or non-functional mock cathelicidin peptides may serve as new anti-inflammatory and immunosuppressive agents. [ABSTRACT FROM AUTHOR]

Systemic lupus erythematosus (SLE) is an autoimmune disease characterized by inflammation of various organs such as skin, kidneys, bones, and brain and the presence of autoantibodies. Although the cause of SLE is not completely understood, environmental factors, genetic susceptibility, hormone factors, and environmental factors are thought to play essential roles in the pathogenesis of SLE. Among environmental factors, the microbiota are linked to the development of different autoimmune diseases. The microbiota in the nasal cavity and gut are involved in SLE development, but the influence of skin microbiota is still unclear. Here, we demonstrated that epithelial cell–specific IκBζ-deficient (NfkbizΔK5) mice showed spontaneous skin inflammation with increased abundance of Staphylococcus aureus on the skin. When S. aureus was epicutaneously applied on NfkbizΔK5 mice, NfkbizΔK5 mice developed SLE-associated autoantibodies, anti-dsDNA antibodies, anti-Sm antibodies, and glomerulonephritis with IgG deposition. Epicutaneous S. aureus application significantly increased staphylococcal colonization on the skin of NfkbizΔK5 mice with reduced expression of several antimicrobial peptides in the skin. This staphylococcal skin colonization promoted caspase-mediated keratinocyte apoptosis and neutrophil activation, inducing the interleukin-23 (IL-23)/IL-17 immune response by activating dendritic cells and T cells. Furthermore, the subcutaneous administration of anti–IL-23p19 and anti–IL-17A antibodies alleviated the systemic autoimmune response. Together, these findings underscore epithelial-immune cross-talk disturbances caused by skin dysbiosis as an essential mediator inducing autoimmune diseases. Skin staph promotes lupus: Systemic lupus erythematosus (SLE) is an autoimmune disease that affects various organs, and the microbiota of the nasal cavity and gut are involved in SLE development. However, it is unclear how the skin microbiota influences SLE. Using an epithelial cell–specific IκBζ-deficient (NfkbizΔK5) mouse model of spontaneous skin inflammation, Terui et al. tested the impact of Staphylococcus aureus colonization of the skin on SLE-associated effects. The authors found that the spontaneous SLE-associated effects seen in the NfkbizΔK5 mice worsened with skin S. aureus colonization. These effects were associated with neutrophil extracellular trap (NET)–induced epidermal apoptosis via the increased production of IL-17A. Thus, skin S. aureus colonization potentially worsens SLE by mediating increased release of NETs. [ABSTRACT FROM AUTHOR]

Rosacea is a chronic inflammatory skin disease with facial redness and acne‐like papules and pustules. The characteristics and background of rosacea patients in Japan have not been well documented. In this study, we retrospectively collected the medical information of rosacea patients, and investigated the background, complications, exacerbating factors, and status of allergy. Between January 2010 and December 2020, 431 cases were diagnosed as rosacea or rosacea‐like dermatitis. We selected 340 patients, in which we could confirm telangiectasia on facial skin. Females and males numbered 266 and 74, respectively. The average age of the first visit was 51.5 years, and the youngest and oldest were 11 and 88 years old. Among 340 cases, 323 had erythematotelangiectatic rosacea, 97 papulopustular rosacea, 20 phymatous rosacea presenting as rhinophyma, and four had symptoms of ocular rosacea. The most common complication was hay fever (93 individuals, 27.4%), and 66 (19.4%) had a medical history of contact dermatitis. Temperature differences (141 individuals, 41.5%) were the most common exacerbating factor followed by sunlight exposure (60 individuals, 17.6%). Seventy‐eight individuals received allergen‐specific immunoglobulin (Ig)E tests, and IgE for cedar was the most frequently observed (46 individuals, 59.0%). High frequencies of IgE for Dermatophagoides pteronyssinus or D. farinae (33 individuals, 42.3%) and house dust I (31 individuals, 39.7%) suggested that environmental conditions at home would affect rosacea symptoms. Since the facial skin is exposed to environmental stimuli every moment, this retrospective observation suggested the importance of the daily lifestyle guidance as well as medical treatments. [ABSTRACT FROM AUTHOR]

Olaparib is recently approved as an anti-tumor agent for several cancers, including castration-resistant prostate cancer, which inhibits poly (adenosine diphosphate-ribose) polymerase, a DNA repair factor. Since olaparib is a newly approved drug, there are few reports of skin disorders that may be triggered by olaparib administration. In this report, we present a case with an olaparib-induced drug eruption presenting multiple purpuras on the patient's fingers and fingertips. The present case suggests that olaparib might induce purpura as nonallergic drug eruption. [ABSTRACT FROM AUTHOR]

Psoriasis is a chronic disease centered on tumor necrosis factor (TNF), interleukin (IL)‐23, and IL‐17 axis. While psoriasis patients benefit from biologics targeting TNF, IL‐17s, and IL‐23 nowadays, suppression of these molecules could modulate the balances of immune systems. However, the incidence of autoimmune disease and T‐helper 2 reaction during biologic treatments for psoriasis patients is not well documented. We retrospectively examined antinuclear antibody (ANA), eosinophil counts, and immunoglobulin E (IgE) levels for psoriasis patients who underwent biologic treatments in our dermatology clinic from June 10, 2010 to January 29, 2020. A cumulative total of 199 biologic treatments were performed for a total of 128 psoriasis patients. Compared to the non‐biologic group of 109 psoriasis patients who received non‐biologic treatment, patients treated with infliximab showed more incidents of high ANA (14%, p = 0.039) and high eosinophils (14%, p = 0.021). The use of brodalumab increased incidents of high eosinophils (21%, p = 0.005) but did not affect increase in ANA and IgE. The increase in high IgE level was observed significantly more during the use of risankizumab (15%, p = 0.011). Methotrexate was the most frequently used concomitant systemic treatment, but methotrexate did not affect ANA, eosinophil counts, and IgE levels. Since the biologics for psoriasis treatment modulate the balance of T‐helper cells, careful observation is required to detect unexpected changes of systemic immune conditions under biologic treatments. [ABSTRACT FROM AUTHOR]

Biologics has had a great impact on psoriasis treatment as well as the life of psoriasis patients. Infliximab (IFX), one of the biologics targeting tumor necrosis factor (TNF), is the first of the biologics introduced to Japanese psoriasis patients. Many patients had benefits of IFX from initial applications and sustained remission of skin lesions and arthritis. Some, however, fall into so‐called secondary failure, in which patients become less responsive to IFX when the treatment is repeated. The mechanism of secondary failure and the background of patients with secondary failure have not been completely elucidated. To address this issue, we retrospectively evaluated psoriasis patients treated with IFX in our department. In this retrospective, single‐center, case‐control study based on the clinical record, a total of 34 patients were enrolled. We excluded 7 patients who discontinued IFX because of adverse events of IFX. We divided other 27 patients into two groups; 16 patients who kept using IFX (Continuance group); and 11 patients who switched to other treatments (Discontinuance group). Among various clinical features, body mass index (BMI), HbA1c, and serum CRP level were significantly higher in the Discontinuance group than the Continuance group. The results indicated that these three clinical features of BMI, HbA1c and serum CRP level before treatment are the predictors of successful IFX treatment and suggest that improvement of metabolic conditions contributes to avoiding secondary failure and discontinuance of IFX. [ABSTRACT FROM AUTHOR]

Genome‐wide association studies have identified more than 60 susceptibility loci for psoriasis, highlighting the role of genetics in psoriasis development. Although the HLA region is suggested as the most prominent susceptibility locus, the role of the HLA haplotype in the development of psoriasis is unclear. The aim of this study is to investigate how HLA haplotype changes affect the onset of psoriasis and which HLA haplotypes are associated with the development of psoriasis. A longitudinal, retrospective case series study of children was conducted at Tohoku University Hospital in Japan, between November 1981 and October 2020. We evaluated a total of 378 pediatric patients who underwent hematopoietic stem cell transplantation in the Department of Pediatrics. The background of these patients and their HLA haplotypes before and after transplantation was assessed. Among the 378 cases, aged 0–22 years old (median age 6) identified, 117 cases received autologous transplantation, 260 cases received allogeneic transplantation, and one case received syngeneic transplantation. Only two cases developed de novo psoriasis, and these cases had acquired HLA‐B46‐Cw1 after allogeneic transplantation. Others who had HLA‐B46‐Cw1 before and after allogeneic transplantation did not develop psoriasis. Our findings suggest that the HLA‐B46 and HLA‐Cw1 combination contributes to the development of psoriasis in this Asian population. [ABSTRACT FROM AUTHOR]

We have reported that the IL-2 Luc assay can detect the effects of chemicals on IL-2 promoter activity by using a dual reporter cell line, 2H4 cells that measure IL-2 promoter-driven luciferase activity (IL2LA) and GAPDH promoter-driven luciferase activity (GAPLA). Since the IL-2 Luc assay cannot detect immunosuppressive drugs that are antimitotic towards rapidly proliferating cells, we attempted to establish a new assay to detect these chemicals by taking advantage of the dual reporter cell properties of 2H4 cells. We first determined the optimal incubation time with drugs and the seeding cell density, and confirmed that the change in GAPLA and IL2LA levels reflects the change in cell count and IL-2 production of 2H4 cells after drug treatment. We designed the IL-2 luciferase lymphotoxicity test (IL-2 Luc LTT) to detect the antimitotic effects of chemicals by modifying the protocol and criteria of the IL-2 Luc assay. To determine the performance of the IL-2 Luc LTT and that of the combination of the IL-2 Luc LTT and the IL-2 Luc assay, we examined 46 drugs: 19 immunosuppressive drugs with different mechanisms of action, 12 anti-cancer drugs, and 15 non-immunosuppressive drugs. The performances of the IL-2 Luc LTT, the IL-2 Luc assay and their combination were 43.3%, 61.3%, and 93.3%, respectively, for sensitivity, 84.6%, 53.3%, and 50.0%, respectively, for specificity, and 55.8%, 58.7%, and 79.5%, respectively, for accuracy. These results demonstrated that the combination of these two assays is promising for the detection of immunosuppressive drugs with different mechanisms of action. [ABSTRACT FROM AUTHOR]

IL-1 functions as an essential pro-inflammatory mediator for the sensitisation of allergic contact dermatitis (ACD). However, studies conducted to date have typically used a limited number of haptens and examined their effects only on murine ACD or murine dendritic cells (DCs). It therefore remains unclear whether IL-1α and/or IL-1β is produced in ACD induced by haptens other than those commonly used in mouse ACD models, and whether they are essential for sensitisation leading to ACD in humans. In addition, it is unclear whether human DCs also produce IL-1α or IL-1β after stimulation by haptens in general. Here, we first demonstrated that 10 haptens (3 extreme, 1 strong, 3 moderate and 3 weak) increased both IL-1α mRNA and IL-1β mRNA expression by the human monocyte cell line THP-1, a commonly used surrogate of DCs in in vitro skin sensitisation tests. Next, we constructed an in vitro skin sensitisation test using a stable IL-1β reporter cell line, THP-G1b, and evaluated whether 88 haptens and 34 non-haptens increase IL-1β reporter activity. We found that 94% of 77 haptens evaluated after considering their applicability domain and solubility in the chosen media stimulated reporter activity. These studies demonstrated that most haptens, irrespective of their potency, increased IL-1β mRNA expression by THP-1 cells, confirming that human DCs also produce IL-1β after stimulation by most haptens. The luciferase assay using THP-G1b cells is thus another skin sensitisation test based on the adverse outcome pathway with reasonable performance. [ABSTRACT FROM AUTHOR]

A 66‐year‐old man with a 2‐year history of suspected scalp eczema with excessive dandruff developed painful swollen joints in the extremities. Four months after developing polyarthritis and polydactylitis, eczema gradually spread to the face. He was referred to our hospital for intractable scalp and facial eczema and polyarthritis. Based on the appearance of the head and facial skin lesions, psoriasis was suspected. Treatment with apremilast (a phosphodiesterase‐4‐inhibitor) was initiated, which swiftly alleviated the skin lesions. The joint deformities persisted, but the pain in the joints disappeared. This case implies that psoriatic arthritis should be suspected even if psoriatic skin lesions are localized to the scalp. [ABSTRACT FROM AUTHOR]

Perifolliculitis capitis abscedens et suffodiens (PCAS) or dissecting cellulitis is a rare condition presenting deep follicular occlusions, follicular ruptures and follicular infections in the scalp area with unknown etiology, which consequently cause primary neutrophilic cicatricial alopecia by the repeated follicular inflammation. PCAS is categorized as one of the "follicular occlusion tetrad" along with hidradenitis suppurativa, acne conglobata and pilonidal cyst. In the pathogenesis of the follicular occlusion tetrad, the involvement of neutrophils and its activator tumor necrosis factor (TNF) have been discussed. Here, we report a case of PCAS that was successfully treated with adalimumab, a human anti‐TNF monoclonal antibody. This is the first Asian case of PCAS that was improved by a TNF inhibitor. [ABSTRACT FROM AUTHOR]

A few reports have described cutaneous allergic reactions to peritoneal dialysis catheters during continuous ambulatory peritoneal dialysis (CAPD).[[1]] Here, we report a rare case of subcutaneous granulomatous reaction with eosinophil infiltration caused by a peritoneal dialysis catheter, and confirmed by skin tests. To the best of our knowledge, no similar case of subcutaneous granulomatous reaction with eosinophil infiltration caused by a peritoneal dialysis catheter has been reported, which was histologically confirmed by eosinophilic infiltration in skin tests. Because a catheter infection clinically resembles a subcutaneous allergic reaction, it is important to suspect CAPD catheter-related reactions if patients do not respond to antibiotics. [Extracted from the article]

We established a luciferase reporter assay system, the Multi-ImmunoTox Assay (MITA), which can evaluate the effects of chemicals on the promoter activities of four cytokines: IL-2, IFN-γ, IL-1β, and IL-8. We previously reported that MITA correctly reflected the change in mRNA of human whole-blood cells treated with dexamethasone, cyclosporine, FK506, or several other immunosuppressive drugs. In this study, we combined MITA with the IL-8 Luc assay to detect skin sensitization chemicals (OECD 442E) (modified MITA: mMITA) and established a data set of 60 chemicals examined by mMITA. Using the mMITA results, chemicals can be classified based on the lowest observed effect level (LOEL) of chemicals in suppressing or augmenting the promoter activities of the four cytokines. Moreover, we demonstrated that K-means clustering and hierarchical clustering of the 60 chemicals based on the LOEL for their effects on IL-2 and IL-8 promoter activities and the judgment by the IL-8 Luc assay resulted in the same 6-cluster solution: cluster 1 with preferential suppression of IL-8, cluster 2 with suppression of IL-2 and a positive IL-8 Luc assay result, cluster 3 with suppression of both IL-2 and IL-8, cluster 4 with no effects on IL-2 or IL-8 and a negative IL-8 Luc assay result, cluster 5 with suppression of both IL-2 and IL-8 and a negative IL-8 Luc assay result, and cluster 6 with preferential suppression of IL-8. These data suggest that mMITA is a promising novel high-throughput approach for detecting unrecognized immunological effects of chemicals and for profiling their immunotoxic effects. [ABSTRACT FROM AUTHOR]

Abstract: Rhododendrol (RD), 4‐(4‐hydroxyphenyl)‐2‐butanol, inhibits melanin synthesis and has been used for skin‐whitening cosmetic products. RD has been very effective in lightening skin pigmentation, but some persons have developed so‐called RD vitiligo, in which vitiligo starts on the face, neck and hands where topical RD has been applied and even extended over skin areas where RD has not been applied. RD vitiligo lesions in some patients have lasted for years and have been resistant to conventional vitiligo treatments. We examined the effects of cholecalciferol on RD vitiligo in a blinded randomized clinical trial. Forty‐eight female RD vitiligo patients were recruited for the trial and were randomized into two groups: the vitamin D (VD)‐intervention group that received daily 5000 IU cholecalciferol for 5 months and the control group. Three blinded investigators scored vitiligo improvement by comparing photographic images of baseline and at 5‐month observation. Serum 25(OH)D3 of RD vitiligo patients was not significantly different from age‐matched healthy volunteers. Twenty‐two in the VD‐intervention group and 23 in the control group completed the 5‐month observation. Serum 25(OH)D3 levels were significantly increased after the 5‐month VD intervention, while the control group did not change. The improvement scores were significantly higher in the VD‐intervention group than the control group. The improvement scores were positively correlated with the serum 25(OH)D3 levels after the 5‐month intervention period but not before the treatment. This blinded randomized clinical trial showed favor in administrating 5000 IU cholecalciferol daily to RD vitiligo patients. [ABSTRACT FROM AUTHOR]

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine carcinoma that only rarely regresses spontaneously. Since little is known about the immunological mechanisms involved in the spontaneous regression of MCC, we describe a case of MCC with spontaneous regression and employed immunohistochemical staining for cytotoxic and immunosuppressive molecules to investigate possible mechanisms involved in the spontaneous regression of MCC. Interestingly, compared to conventional MCC, tumor-infiltrating lymphocytes in MCC with spontaneous regression contained higher numbers of CD8+ cells and granulysin-bearing cells and lower numbers of CD206+ cells. Our present study suggests one of the possible reasons for the spontaneous regression of MCC. [ABSTRACT FROM AUTHOR]