Solar urticaria: clinical characteristics, treatment effectiveness, long-term prognosis, and QOL status in 29 patients

Introduction

Solar urticaria (SU), a relatively rare skin inflammatory and photosensitivity disease, is often resistant to standard urticaria treatment. Quality of life (QOL) among SU patients has not been extensively explored. This study was performed to clarify the clinical features and effectiveness of therapies (e.g., hardening therapy) for SU and to determine QOL among SU patients.

Methods

The authors examined the characteristics, treatments, and QOL statuses of 29 Japanese SU patients using medical records and a questionnaire approach.

Results

Among 29 patients, H1 antihistamine therapy (H1) was effective in 22 (75.8%) patients. H2 antihistamine therapy (H2) was effective in three of seven (42.9%) patients. Ultraviolet radiation A (UVA) hardening therapy was effective in eight of nine (88.9%) patients. Visible light (VL) hardening therapy was ineffective in three of three patients. In one patient who underwent both UVA and VL hardening therapy, only UVA hardening therapy was effective. In the questionnaire, 18 patients (90%) reported some improvement compared with disease onset (four had complete remission, six had completed treatment although mild symptoms persisted, and eight were receiving treatment with moderate symptoms), whereas two patients reported exacerbation. Patients in complete remission had a mean disease duration of 4 years, whereas patients not in remission had a mean disease duration of 8.8 years. The mean Dermatology Life Quality Index (DLQI) score for the current status was 7.4. There was a correlation between DLQI and symptom/treatment status. However, neither DLQI and action spectra nor DLQI and treatments exhibited significant differences.

Discussion

The questionnaire revealed current QOL status and long-term prognosis in SU patients. Compared with disease onset, most patients showed improvement when assessed for this study. Both H1 and H2 should be attempted for all SU patients. UVA hardening therapy may be an option for SU patients with an action spectrum that includes UVA.

Three Cases of Occupational Allergic Contact Dermatitis Where Causative Agents Were Identified Using Patch Test Panel S

Identifying the causative substances of occupational contact dermatitis is challenging because of several chemicals and materials in the workplace that can cause contact dermatitis. We experienced three cases of intractable eczema identified as work-related contact dermatitis by Patch Test Panel S, which helped identify the possible substances. We experienced three cases of occupational allergic contact dermatitis, and their causative agents were identified by Patch Test Panel S. Although there are some limitations, Patch Test Panel S might be useful to determine the substrates to cause allergic contact dermatitis in occupational scenarios.

Cholinergic Urticaria: Subtype Classification and Clinical Approach

Cholinergic urticaria (CholU) is a subtype of chronic inducible urticaria with a chief complaint of itching and/or stinging, painful papular wheals that develop simultaneously with sweating. This review specifically focuses on several subtypes of CholU and specifically investigates the relationship between CholU and anhidrosis. We review recent publications and update the evidence around CholU, including the epidemiology, clinical features, diagnostic approaches, physiopathology, subtype classification, and therapeutic approaches. Multiple mechanisms contribute in a complex manner to the development of CholU, including histamine, sweat allergy, cholinergic-related substances, poral occlusion, and hypohidrosis/anhidrosis. A new schematic of the currently known pathological conditions has been created. Specific methods for diagnosing CholU, a provocation test, and evaluation methods for disease severity/activity and disease burden of CholU are summarized. The characteristics of the diseases that should be differentiated from CholU and examination methods are also summarized. The primary finding of this review is that CholU should be categorized based on the etiology and clinical characteristics of each subtype to properly manage and treat the disease. This categorization leads to improvement of therapeutic resistance status of this disease. In particular, a sweating abnormality should be given more attention when examining patients with CholU. Because CholU is not a homogeneous disease, its subtype classification is important for selection of the most suitable therapeutic method. Further elucidation of the pathophysiology of each subtype is expected.

Bowel obstruction secondary to internal hernia in a hereditary angioedema patient: a case report

BACKGROUND

Gastrointestinal attacks are frequent symptoms in patients diagnosed with hereditary angioedema (HAE). Cases of self-limited bowel intussusception and unneeded exploratory laparotomy due to lack of knowledge about HAE have been reported. Furthermore, after the introduction of C1-esterase inhibitor (C1-INH) concentrate, the recommended medication for HAE attacks, treatment has become typically medical in nature. We share a rare case where operative exploration was indicated to resolve a mechanical small bowel obstruction secondary to an HAE attack.

CASE REPORT

An 80-year-old woman with HAE presented with lower left abdominal pain, vomiting, and nausea. Computed tomography (CT) showed edema of the small bowel and stomach as well as possible signs of mechanical small bowel obstruction. The patient was treated with C1-INH concentrate but showed only mild signs of relief, warranting diagnostic laparoscopy. Intraoperative findings showed internal herniation and strangulation of the small bowel caused by adhesions forming a band. After surgical intervention, no bowel resection was needed.

CONCLUSION

Although C1-INH concentrate remains the principal treatment for HAE, gastrointestinal attacks may potentially cause surgical emergencies.

IgE receptor responsiveness of basophils in chronic inducible urticaria

Introduction

Chronic inducible urticaria (CIndU) is a subgroup of chronic urticaria induced by a specific stimulus. We evaluated basophil characteristics in patients with CIndU and compared with those in patients with chronic spontaneous urticaria (CSU) and healthy controls (HCs).

Methods

Blood was collected from patients, and a basophil activation test (BAT) was performed. Basophil responsiveness and surface marker expression in patients with CIndU were compared with those in patients with CSU and HCs. For some patients with CIndU, blood was collected before and after wheals were induced. In these cases, we compared the responsiveness of basophils before and after the appearance of wheals.

Result

HCs (n=23) and patients with CIndU (n=24) or CSU (n=38) were enrolled in the study. The degree of basophil activation at steady state in patients with CIndU was higher than in HCs. Basophil responsiveness via high-affinity IgE receptor (FcϵRI) stimulation with anti-IgE or anti-FcϵRI antibody in patients with CIndU was equivalent to that in HCs, and higher than that in patients with CSU. No abnormalities in IgE and FcϵRI expressions on the surface of basophils in patients with CIndU were observed. When we induced wheals in some patients with CIndU and performed a BAT before and after the appearance of wheals, no significant changes were found.

Conclusion

Peripheral blood basophils in CIndU were slightly activated at steady state, but no abnormalities in basophil responsiveness. In future, a higher number of cases should be enrolled to confirm the role of basophils and refine therapeutic targets for CIndU.

Lower efficacy of omalizumab in older adults with chronic spontaneous urticaria

Omalizumab is known to be effective in treating chronic spontaneous urticaria (CSU) with an inadequate response to H₁ -antihistamine. Although many reports have described pre-treatment biomarkers to predict the efficacy of omalizumab in CSU, there are few reports that examined the relationship between age and the therapeutic effectiveness of omalizumab. Thus, we aimed to investigate the relationship between response to omalizumab and age. This retrospective study comprised 52 CSU patients receiving three consecutive omalizumab courses during the period from April 2017 to March 2021. Participants were categorized as responders or non/partial responders using the urticaria control test to evaluate clinical variables on week 12. The female rate tended to be higher, and the mean age and the median disease duration tended to be lower with no significance in responders compared with in non/partial responders. In addition, they exhibited no significant differences regarding serum immunoglobulin E levels, basophil counts, eosinophil counts, d-dimer, and autologous serum skin test results reported as predictor in the past between two groups. Interestingly, when patients were categorized as age <65 years or ≥65 years, those in the ≥65 years group had a significantly lower response to omalizumab than those aged <65 years. These findings suggest that physicians should keep in mind that the age of their CSU patients may be a predictor of the therapeutic efficacy of omalizumab.

Activated steady status and distinctive FcεRI-mediated responsiveness in basophils of atopic dermatitis

BACKGROUND

Although basophils are considered to play an important role for maintenance of type 2 inflammation in atopic dermatitis (AD), studies on basophils in AD patients are limited. Some studies have reported the activation status, including CD203c and CD63, of peripheral blood basophils in AD patients.

METHODS

We examined the features of circulating basophils in AD patients, assessed cell surface marker expressions and total serum IgE, and compared basophil responsiveness to stimulation between AD patients and healthy controls (HCs). In addition, the correlations among AD severity, laboratory factors, and features of basophils were examined. Blood samples from 38 AD patients and 21 HCs were analyzed. Basophil response markers CD203c and CD63, and expression of surface-bound IgE and FcεRI on basophils were measured. CD203c and CD63 expressions induced by stimulation with anti-IgE and anti-FcεRI antibodies were measured. Clinical/laboratory factors including total serum IgE were examined for correlations with these basophil parameters.

RESULTS

Baseline CD203c and CD63 expression on basophils were significantly higher in AD patients compared with HCs. The CD203c/CD63 response ratio to anti-FcεRI stimulation was higher than that to anti-IgE stimulation in AD patients, but not HCs. FcεRI expression on basophils was higher in AD patients than in HCs, although surface-bound IgE on basophils was equivalent. Total serum IgE had negative correlations with surface-bound IgE and CD63 responsiveness to anti-IgE stimulation.

CONCLUSIONS

Basophils were spontaneously activated under steady-state conditions in AD patients and responsiveness to anti-IgE stimulation was lower than in HCs. Despite high serum IgE and high basophil FcεRI expression, surface-bound IgE on basophils remained relatively low. Basophils might be suppressed or exhausted regarding FcεRI signaling via IgE in severe AD.

Improved FcεRI-Mediated CD203c Basophil Responsiveness Reflects Rapid Responses to Omalizumab in Chronic Spontaneous Urticaria

BACKGROUND

Omalizumab is effective in patients with chronic spontaneous urticaria (CSU) although its mechanism of action is poorly understood. Several studies reported that decreased high-affinity IgE receptor (FcεRI)-mediated histamine release and/or responsiveness was characteristic of basophils in patients with CSU. However, few studies have focused on the relationship between changes in basophil responsiveness via FcεRI after omalizumab treatment and the therapeutic effect in patients with CSU.

OBJECTIVE

To assess basophil responsiveness via FcεRI stimulation, as well as FcεRI expression and IgE binding on blood basophils from patients with CSU before and after omalizumab treatment and its possible association with the clinical response.

METHODS

We analyzed 34 patients with CSU treated with omalizumab who were categorized as fast responders (FRs) (n = 20) and non or slow responders (N/SRs) (n = 14). CD203c expression induced by FcεRI stimulation, and IgE and FcεRI expressions on blood basophils from patients with CSU before and after omalizumab treatment were analyzed. Basophil responsiveness via FcεRI stimulation was observed in vitro using basophils pretreated with omalizumab.

RESULTS

FRs had increased CD203c responsiveness after treatment with omalizumab compared with N/SRs. This improvement of basophil responsiveness via FcεRI stimulation in FRs was not observed in peripheral blood basophils preincubated with omalizumab in vitro, suggesting that omalizumab does not directly affect circulating pre-existing abnormal basophils.

CONCLUSION

Increased basophil responsiveness via FcεRI after omalizumab treatment is associated with the therapeutic effect and mechanism of action of omalizumab.

SIRPα on CD11c+ cells induces Th17 cell differentiation and subsequent inflammation in the CNS in experimental autoimmune encephalomyelitis

Signal regulatory protein α (SIRPα) is expressed predominantly on type 2 conventional dendritic cells (cDC2s) and macrophages. We previously showed that mice systemically lacking SIRPα were resistant to experimental autoimmune encephalomyelitis (EAE). Here, we showed that deletion of SIRPα in CD11c⁺ cells of mice (Sirpa^ΔDC mice) also markedly ameliorated the development of EAE. The frequency of cDCs and migratory DCs (mDCs), as well as that of Th17 cells, were significantly reduced in draining lymph nodes of Sirpa^ΔDC mice at the onset of EAE. In addition, we found the marked reduction in the number of Th17 cells and DCs in the CNS of Sirpa^ΔDC mice at the peak of EAE. Whereas inducible systemic ablation of SIRPα before the induction of EAE prevented disease development, that after EAE onset did not ameliorate the clinical signs of disease. We also found that EAE development was partially attenuated in mice with CD11c⁺ cell-specific ablation of CD47, a ligand of SIRPα. Collectively, our results suggest that SIRPα expressed on CD11c⁺ cells, such as cDC2s and mDCs, is indispensable for the development of EAE, being required for the priming of self-reactive Th17 cells in the periphery as well as for the inflammation in the CNS.

Clinical utility of the basophil activation test in the diagnosis of sweat allergy

BACKGROUND

Many patients with atopic dermatitis and cholinergic urticaria display an immediate-type allergy to autologous sweat. Although the histamine release test (HRT) using semi-purified sweat antigen (QR) was available for the detection of immediate sweat allergy, the existence of HRT low responders could not be disregarded. Furthermore, it has not been established whether the results of the HRT are consistent with the autologous sweat skin test (ASwST). We aimed to compare the HRT and basophil activation test (BAT) for the diagnosis of immediate sweat allergy.

METHODS

The HRT and BAT were performed on 47 subjects (35 ASwST positive, 12 negative) whose symptoms had worsened on sweating. For the BAT, blood was incubated with QR or crude sweat and CD203c upregulation was assessed. A commercial HRT was performed and histamine release induced by QR was quantified.

RESULTS

When excluding non-responders for anti-IgE antibody, the BAT using QR and the HRT had a sensitivity of 100% and 44% and specificity of 75% and 100%, respectively. The BAT and HRT had a positive predictive value of 91.3% and 100% and negative predictive value of 100% and 30%, respectively. The BAT detected 0% non-responders, whereas the HRT identified 22.5%. When using crude sweat for the BAT, the false-positives observed when using QR were not detected.

CONCLUSIONS

The BAT using QR displayed a higher sensitivity and negative predictive value and a lower number of non-responders compared with the HRT. Furthermore, the BAT using crude sweat can also be an alternative tool for the ASwST.

Efficacy of switching to bilastine, a histamine H1 receptor antagonist, in patients with chronic spontaneous urticaria (H1-SWITCH): study protocol for a randomized controlled trial

BACKGROUND

Chronic spontaneous urticaria (CSU) is characterized by the spontaneous appearance of wheals, angioedema, or both for > 6 weeks. Continuous treatment with H1-antihistamines is used as a first-line treatment for CSU. However, H1-antihistamine treatment leads to absence of symptoms in less than 50% of patients with CSU. Although Japanese guidelines for the diagnosis and treatment of urticaria recommend an increase in the H1-antihistamine dose or a switch to other H1-antihistamines, there is no evidence supporting a switch to other H1-antihistamines in patients with refractory CSU who are unresponsive to H1-antihistamines at the licensed dose.

METHODS

We will conduct a multicenter, open-label, non-inferiority, randomized, parallel, comparison study to determine if the efficacy of bilastine 20 mg is not inferior to that of a twofold H1-antihistamine dose increase in patients with refractory CSU who are unresponsive to H1-antihistamines at the licensed dose. This study will be performed at 15 academic hospitals in Japan, and the administration period (increasing the H1-antihistamine dose twofold vs. switching to bilastine 20 mg) will be 7 days. Participants (n = 150) will be randomized to either an increased H1-antihistamine dose or a switch to bilastine 20 mg at a 1:1 ratio. The primary endpoint, mean of the total symptom score of 5-7 days after the intervention, will be evaluated. The secondary objective is to determine if the safety of bilastine 20 mg regarding somnolence is superior to that of a twofold dose increase of H1-antihistamines. This will be measured by a change in the Japanese version of the Epworth Sleepiness Scale from baseline to 7 days after starting the intervention.

DISCUSSION

This multicenter, open-label, non-inferiority, randomized, parallel, comparison study will be, to our knowledge, the first well-designed clinical study to evaluate the efficacy of a switch to other H1-antihistamines in patients with refractory CSU who are unresponsive to H1-antihistamines at the licensed doses. This trial will provide evidence of the efficacy and safety of bilastine when treatment is switched in patients with refractory CSU who are unresponsive to H1-antihistamines at the licensed dose.

TRIAL REGISTRATION

Japan Registry of Clinical Trials (jRCT), jRCTs051180105. Registered on 8 March 2019.

Adapalene Gel 0.1% Versus Placebo as Prophylaxis for Anti-Epidermal Growth Factor Receptor-Induced Acne-Like Rash: A Randomized Left-Right Comparative Evaluation (APPEARANCE)

LESSONS LEARNED

The results of the APPEARANCE trial indicate that adapalene does not prevent acne-like rash over placebo when added to topical moisturizer and oral minocycline but instead may have a detrimental effect. Therefore, adapalene is not recommended as prophylaxis against acne-like rash induced by anti-epidermal growth factor receptor therapies.Given that acne-like rash was completely controlled with placebo in approximately half of patients, predictive measures to identify patients needing intensive prophylaxis are required.

BACKGROUND

Anti-epidermal growth factor receptor (EGFR) therapies are frequently associated with acne-like rash. To evaluate the prophylactic efficacy of adapalene, a topical retinoid used as first-line therapy for acne vulgaris, we conducted a randomized, placebo-controlled, evaluator-blinded, left-right comparative trial.

METHODS

Patients with non-small cell lung, colorectal, or head and neck cancer scheduled to receive anti-EGFR therapies were randomly assigned to once-daily adapalene application on one side of the face, with placebo on the other side. All patients had topical moisturizer coapplied to both sides of the face, and received oral minocycline. The primary endpoint was the difference in total facial lesion count of acne-like rash at 4 weeks. Secondary endpoints included complete control rate (CCR) of acne-like rash (≤5 facial lesions) and global skin assessment (Investigator's Global Assessment [IGA] scale, grade 0-4) at 4 weeks. Two blinded dermatologists independently evaluated the endpoints from photographs.

RESULTS

A total of 36 patients were enrolled, of whom 26 were evaluable. Adapalene treatment was associated with a greater lesion count than placebo at 4 weeks, although the difference was not statistically significant (mean, 12.6 vs. 9.8, p = .12). All four patients with a difference >10 in lesion count between face sides had a greater count on the adapalene-treated side. No significant differences were observed in CCR of acne-like rash (54% vs. 50%) or IGA scale (mean grade, 1.9 vs. 1.7) between the adapalene and placebo sides.

CONCLUSION

Adapalene is not recommended as prophylaxis against acne-like rash induced by anti-EGFR therapies.

Cross-sectional survey on disease severity in Japanese patients with harlequin ichthyosis/ichthyosis: Syndromic forms and quality-of-life analysis in a subgroup

BACKGROUND

Congenital ichthyoses (CIs) adversely affect quality of life (QOL) in patients. However, the effects of CIs on patient QOL have not been studied sufficiently.

OBJECTIVE

To investigate the association between disease severity and QOL in patients with harlequin ichthyosis (HI) and ichthyosis: syndromic forms (ISFs) METHODS: Clinical information of patients with HI and ISFs from 2010 to 2015 were obtained from 100 dermatology departments/divisions of principal institutes/hospitals throughout Japan. We examined the relationship between disease severity and QOL in patients with HI and ISFs. Patients who were aged 8 years or older and participated in a multicenter retrospective questionnaire survey in Japan were assessed by dermatology life quality index (DLQI, range of 0-30) and clinical ichthyosis score (range of 0-100).

RESULTS

Netherton syndrome patients had a significantly higher risk of allergy to food or environmental allergens than patients with other phenotypes. Keratitis-ichthyosis-deafness (KID) syndrome patients showed a significantly higher risk of skin infections than patients with other phenotypes. Complete data on DLQI were obtained from 13 patients, whose median age was 21 (8-71) years. Nine patients were male, and 4 were female. Systemic retinoids were administrated to 2 of the 3 HI patients. The Spearman's correlation coefficient between the clinical ichthyosis score and DLQI was 0.611 (P < 0.05).

CONCLUSION

We confirmed that Netherton syndrome and KID syndrome patients have a higher risk of allergy to food or environmental allergens and of skin infections, respectively. QOL impairment correlates with disease severity in HI and ISFs patients.

Anti-Inflammatory Role of Langerhans Cells and Apoptotic Keratinocytes in Ultraviolet-B-Induced Cutaneous Inflammation

UV radiation, particularly UVB, is the major risk factor for the induction of skin cancer, and it induces skin inflammation and immunosuppression. Although reports documented that Langerhans cells (LCs) play various roles in photobiology, little is known about whether they contribute to UVB-induced cutaneous inflammation. Recently, the anti-inflammatory effect of apoptotic cells was noted. This study focuses on the roles of LCs and apoptotic cells in UVB-induced cutaneous inflammation. We show that LCs are essential for resolution of UVB-induced cutaneous inflammation. Administration of quinolyl-valyl-O-methylaspartyl-[2,6-difluophenoxy]-methyl ketone, a broad-spectrum caspase inhibitor with potent antiapoptotic properties, inhibited the formation of UVB-induced apoptotic cells and aggravated UVB-induced cutaneous inflammation in wild-type mice. In contrast, exacerbation of UVB-induced cutaneous inflammation following quinolyl-valyl-O-methylaspartyl-[2,6-difluophenoxy]-methyl ketone administration was not observed in LC-depleted mice. These results suggest that the interaction between LCs and apoptotic cells is critical for resolution of UVB-induced cutaneous inflammation. Interestingly, UVB-induced apoptotic keratinocytes were increased in LC-depleted mice. In addition, we revealed that UVB-induced apoptotic keratinocytes were phagocytosed by LCs ex vivo and that prolongation of UVB-induced cutaneous inflammation following treatment with Cytochalasin D, an inhibitor of phagocytosis, was partially attenuated in LC-depleted mice. Collectively, our findings demonstrate that the interaction between LCs and apoptotic cells, possibly via LC-mediated phagocytosis of apoptotic keratinocytes, has an essential anti-inflammatory role in the resolution of UVB-induced cutaneous inflammation.

Cholinergic urticaria: epidemiology, physiopathology, new categorization, and management

PURPOSE

The aim of this study was to review the evidence on the epidemiology, physiopathology, categorization, and management of cholinergic urticaria. We specifically focused on several subtypes of cholinergic urticaria and investigated the relationship between cholinergic urticaria and idiopathic anhidrosis.

METHODS

Using an integrative approach, we reviewed publications addressing the epidemiology, clinical features, diagnostic approach, physiopathology, subtype classification, and therapeutic approach to cholinergic urticaria.

RESULTS

Multiple mechanisms were found to contribute to the development of cholinergic urticaria. This disorder should be classified based on the pathogenesis and clinical characteristics of each subtype. Such a classification system would lead to better management of this resistant condition. In particular, sweating function should be given more attention when examining patients with cholinergic urticaria.

CONCLUSIONS

Because cholinergic urticaria is not a homogeneous disease, its subtype classification is essential for selection of the most suitable therapeutic method.

Anti-SIRP antibodies as a potential new tool for cancer immunotherapy

Tumor cells are thought to evade immune surveillance through interaction with immune cells. Much recent attention has focused on the modification of immune responses as a basis for new cancer treatments. SIRPα is an Ig superfamily protein that inhibits phagocytosis in macrophages upon interaction with its ligand CD47 expressed on the surface of target cells. Here, we show that SIRPα is highly expressed in human renal cell carcinoma and melanoma. Furthermore, an anti-SIRPα Ab that blocks the interaction with CD47 markedly suppressed tumor formation by renal cell carcinoma or melanoma cells in immunocompetent syngeneic mice. This inhibitory effect of the Ab appeared to be mediated by dual mechanisms: direct induction of Ab-dependent cellular phagocytosis of tumor cells by macrophages and blockade of CD47-SIRPα signaling that negatively regulates such phagocytosis. The antitumor effect of the Ab was greatly attenuated by selective depletion not only of macrophages but also of NK cells or CD8⁺ T cells. In addition, the anti-SIRPα Ab also enhances the inhibitory effects of Abs against CD20 and programmed cell death 1 (PD-1) on tumor formation in mice injected with SIRPα-nonexpressing tumor cells. Anti-SIRPα Abs thus warrant further study as a potential new therapy for a broad range of cancers.

UVB Exposure Prevents Atherosclerosis by Regulating Immunoinflammatory Responses

OBJECTIVE

UVB irradiation is an established treatment for immunoinflammatory cutaneous disorders and has been shown to suppress cutaneous and systemic inflammatory diseases through modulation of the adaptive immune response. However, it remains unknown whether UVB irradiation prevents an immunoinflammatory disease of arteries such as atherosclerosis.

APPROACH AND RESULTS

Here, we show that UVB exposure inhibits the development and progression of atherosclerosis in atherosclerosis-prone mice by expanding and enhancing the functional capacity of CD4⁺ forkhead box P3⁺ regulatory T cells and regulating proatherogenic T-cell responses. Experimental studies in Langerhans cell-depleted mice revealed that epidermal Langerhans cells play a critical role in UVB-dependent induction of CD4⁺ forkhead box P3⁺ regulatory T cells, suppression of proatherogenic T-cell responses, and prevention of atherosclerotic plaque development.

CONCLUSIONS

Our findings suggest the skin immune system as a novel therapeutic target for atherosclerosis and provide a novel strategy for the treatment and prevention of atherosclerosis.

Dendritic cell SIRPα regulates homeostasis of dendritic cells in lymphoid organs

Signal regulatory protein α (SIRPα), an immunoglobulin superfamily protein that is expressed predominantly in myeloid lineage cells such as dendritic cells (DCs) or macrophages, mediates cell-cell signaling. In the immune system, SIRPα is thought to be important for homeostasis of DCs, but it remains unclear whether SIRPα intrinsic to DCs is indeed indispensable for such functional role. Thus, we here generated the mice, in which SIRPα was specifically ablated in CD11c(+) DCs (Sirpa(Δ) (DC) ). Sirpa(Δ) (DC) mice manifested a marked reduction of CD4(+) CD8α(-) conventional DCs (cDCs) in the secondary lymphoid organs, as well as of Langerhans cells in the epidermis. Such reduction of cDCs in Sirpa(Δ) (DC) mice was comparable to that apparent with the mice, in which SIRPα was systemically ablated. Expression of SIRPα in DCs was well correlated with that of either endothelial cell-selective adhesion molecule (ESAM) or Epstein-Barr virus-induced molecule 2 (EBI2), both of which were also implicated in the regulation of DC homeostasis. Indeed, ESAM(+) or EBI2(+) cDCs were markedly reduced in the spleen of Sirpa(Δ) (DC) mice. Thus, our results suggest that SIRPα intrinsic to CD11c(+) DCs is essential for homeostasis of cDCs in the secondary lymphoid organs and skin.

A case of lichen planus pemphigoides successfully treated with a combination of cyclosporine a and prednisolone

Lichen planus pemphigoides (LPP) is a rare clinical variant of bullous pemphigoid (BP). A 35-year-old female patient presented to our hospital complaining of pruritic violaceous-colored plaques or papules on the extremities. Tense vesicles were also seen on the soles. Skin biopsies from the papules and vesicles demonstrated lichen planus and BP, respectively. Direct immunofluorescence demonstrated linear IgG and C3 deposition on the basement membrane zone. Indirect immunofluorescence on 1 M NaCl split skin detected IgG reactivity with the epidermal side. Enzyme-linked immunosorbent assay also detected anti-BP180 antibodies. After treatment with oral prednisolone alone had failed, low-dose cyclosporine A (CyA) was added. The clinical symptoms immediately improved and the titer of the anti-BP180 antibodies decreased. Although there is little information about the treatment of recalcitrant LPP, additional CyA appeared to be beneficial.