Adenosine induces IL-31 secretion by T-helper 2 cells: Implication for the effect of adenosine on atopic dermatitis and its therapeutic strategy

Interleukin (IL)-31 is a recently-identified cytokine with a well-defined role in the pathogenesis of pruritus. Previously, we reported that adenosine upregulates IL-17A secretion by T-helper (Th)17 cells; however, the effect of adenosine on T cell subsets other than Th17 remains unclear. In this report, we show that adenosine upregulated production of IL-31 by cluster of differentiation (CD)4⁺ T cells. IL-31 was also upregulated by administration of an adenosine A2a receptor (A2aR) agonist (PSB0777), and adenosine-mediated IL-31 production was inhibited by an A2aR antagonist (istradefylline). Production of Th2-related cytokines (IL-4, IL-10, and IL-13) by CD4⁺ T cells showed the same tendency. Immune subset analyses revealed that adenosine upregulated IL-31 secretion by CD4⁺ chemokine receptor 3^high T cells, and that Th2 cells differentiated from naïve CD4⁺ T cells. Administration of istradefylline to mice with atopic dermatitis suppressed the symptoms, suggesting that A2aR antagonists are an effective treatment for inflammatory dermatitis. Taken together, the results indicate that adenosine upregulates secretion of Th2-related cytokines by effector T cells in the skin, thereby triggering atopic dermatitis and associated pruritus.

Ropinirole inhibits inflammatory cytokine production in gingival epithelial cells and suppresses alveolar bone loss in an experimental rat model of periodontitis

The present study explored whether the dopamine 2-like receptor agonist, ropinirole, a drug used for treating Parkinson's disease, suppresses neutrophilic inflammation and alveolar bone loss in an experimental rat model of periodontitis. Periodontitis is a neutrophilic inflammatory disease caused by periodontal pathogens. An excessive T helper (Th)17 immune response is involved in the progression of periodontitis, and interleukin (IL)-17 promotes the exacerbation of inflammation and alveolar bone destruction. Recent evidence has suggested that dopamine signaling plays a key role in Th17 cell differentiation, and that dopamine 2-like receptor agonists suppress cytokine production from Th17 cells. We previously demonstrated that tannic acid, which is a dopamine 2-like receptor agonist, inhibits alveolar bone resorption in an experimental model of periodontitis. The present study used a carrageenan-induced rat model of periodontitis with or without ropinirole. Micro-computed tomography analysis was performed. Cells of the murine gingival epithelial cell line GE1 were stimulated with carrageenan and IL-17A in the presence or absence of ropinirole. The anti-inflammatory effect of ropinirole was analyzed using reverse transcription- quantitative PCR and enzyme-linked immunosorbent assay. Subsequently, in the carrageenan-induced rat model of periodontitis, alveolar bone resorption was observed in the maxillary second molar by micro-computed tomography analysis. Intriguingly, ropinirole suppressed the alveolar bone destruction. The expression levels of C-X-C motif chemokine ligand 1 (CXCL1) and IL-17 receptor A (IL-17RA) in GE1 cells were increased by carrageenan, and CXCL1 expression in GE1 cells was upregulated under IL-17A stimulation. Moreover, ropinirole inhibited CXCL1 and IL-17RA expression in GE1 cells in the presence of IL-17A and carrageenan. Finally, haloperidol promoted CXCL1 expression in GE1 cells in the presence of carrageenan. Overall, these findings suggested that ropinirole suppressed neutrophilic inflammation and alveolar bone destruction in periodontitis by inhibiting CXCL1 expression in gingival epithelial cells through the dopamine 2-like receptor. Thus, ropinirole shows promise as a drug for the treatment of periodontitis.

Elevated White Blood Cell Count and Lactate Dehydrogenase Levels Are Important Markers for Diagnosing Relapse of Adult-onset Still's Disease under Tocilizumab Use

We encountered a case of refractory adult-onset Still's disease (AOSD) with two relapses. Prednisolone and methotrexate were begun as induction therapy, resulting in the patient's first relapse during tapering of prednisolone. After the introduction of tocilizumab, she achieved remission. However, she experienced a second relapse following prednisolone tapering. While lactate dehydrogenase (LDH) levels and white blood cell (WBC) counts increased in both relapses, interleukin-6 (IL-6) suppression resulted in stable C-reactive protein and ferritin levels in the second relapse. A comparison of the two relapses indicated that increases in both WBC counts and LDH levels can aid in the diagnosis of AOSD relapse.

Istradefylline, an adenosine A2a receptor antagonist, inhibits the CD4+ T-cell hypersecretion of IL-17A and IL-8 in humans

Extracellular adenosine produced from ATP plays a role in energy processes, neurotransmission, and inflammatory responses. Istradefylline is a selective adenosine A2a receptor (A2aR) antagonist used for the treatment of Parkinson's disease. We previously showed using mouse models that adenosine primes hypersecretion of interleukin (IL)-17A via A2aR, which plays a role in neutrophilic inflammation models in mice. This finding suggests that adenosine is an endogenous modulator of neutrophilic inflammation. We, therefore, investigated the in vitro effect of istradefylline in humans. In the present study, using human peripheral blood mononuclear cells (PBMCs), we tested the effect of adenosine, adenosine receptor agonists and istradefylline on cytokine responses using mixed lymphocyte reaction (MLR), PBMCs, CD4⁺ T cells, and Candida albicans antigen (Ag)-stimulated PBMCs. We showed that adenosine and an A2aR agonist (PSB0777) promoted IL-17A and IL-8 production from human PBMCs, and istradefylline suppressed this response. In addition, istradefylline inhibited not only the IL-17A and IL-8 production induced by adenosine but also that from C. albicans Ag-stimulated PBMCs. These results indicate that adenosine-mediated IL-17A and IL-8 production plays a role in neutrophilic inflammation, against which istradefylline should be effective.

Signaling via dopamine and adenosine receptors modulate viral peptide-specific and T-cell IL-8 response in COVID-19

B-cell but not T-cell responses have been extensively studied using peripheral blood mononuclear cells (PBMCs) obtained from patients with coronavirus disease 2019 (COVID-19). Our recent study showed that not only T-helper (Th) 17 but also Th1 cells directly produce interleukin (IL)-8, a major source of neutrophilic inflammation, which is also known to induce disseminated intravascular coagulation (DIC) in COVID-19 patients. Neutrophilic inflammation caused by IL-17A or IL-8 can be fatal; thus, therapeutic intervention is highly expected. The present study aimed to investigate the T-cell responses in the Japanese patients. We synthesized spike protein-derived 15-mer peptides that are expected to bind to HLA class II allelic products frequently observed in the Japanese population, and checked the T-cell responses in Japanese patients with COVID-19. We have found that (i) patients show marked IL-8 but not IL-17A responses; (ii) these responses are restricted by HLA-DR; and (iii) IL-8 responses are abrogated by a dopamine D2 like receptor (D2R) agonist, ropinirole, and an adenosine A2a receptor (A2aR) antagonist, istradefylline. Compounds used for the treatment of Parkinson's disease may ease DIC in COVID-19. (183 words).

OP0238 CLINICAL ANALYSIS OF 34 CASES OF CARDIAC COMPLICATIONS REQUIRING SURGICAL INTERVENTION IN SYSTEMIC LUPUS ERYTHEMATOSUS AND ASSESSMENT ABOUT MECHANISM OF DEVELOPMENT WITH IMMUNOLOGICAL ANALYSIS

Background

In cases of systematic lupus erythematosus (SLE) that lead to surgery due to the development of heart diseases such as valvular disease, ischemic heart disease and aortic aneurysm, early detection and careful monitoring are important. An absence of background diseases or immunopathological examination of the myocardial tissue in SLE cases with cardiovascular lesions demonstrates the lack of knowledge in this area. In recent years, however, there have been reports of neutrophil extracellular traps being involved in the fulminant onset of SLE.

Objectives

This study aimed to analyze clinically and immunohistopathologically the pathophysiology of heart diseases associated with SLE.

Methods

We performed left atrial appendage resection in 34 patients, including patients with cardiovascular lesions, who underwent heart surgery for SLE complications from 2012 to 2021. Tissue analysis was conducted in 9 cases. The left atrial appendage, in cases of non-collagen valvular disease, was used as the control. Tissue staining of cardiomyocytes was carried out by adding anti-neutrophil extracellular(NE) antibodies(Abs) to anti-human IgG antibody (Ab), anti-IgM Ab and anti-C3 Ab.

Results

Of the 34 SLE patients 14 had valvular disease, 8 had ischemic heart disease and 12 had aneurysms. Preoperative SLE activity was relatively stable with only 1 patient below the CH50 standard and 6 patients above the anti-DNA Ab standard. The Ab positivity rate for the patients in this study was higher than that of the 687 SLE patients who were previously tested in 2019. The presence of anti-CL Abs was 55.6%, which was higher than the 25.5% observed in previous SLE patients. In this study, anti-SS-A and anti-RNP Abs tended to be relatively numerous. An example of immunohistochemical staining of IgG in the left atrial appendage is presented (Figure 1a). IgG deposits were not observed on the left side of the myocardial fibers in the control group, whereas IgG deposits were observed on the right side in the SLE group. Deposits were also observed in tissues that were not located in the affected areas. The presence or absence of tissue deposition in the myocardial fibers and clinical findings in 2 cases of the control group and 9 cases of the SLE complication group are reported in Table 1. IgG deposits were found in the myocardial fibers of 6 of the 9 patients in the SLE complication group, and deposits were found in the left atrial appendage tissue regardless of the type of heart disease, suggesting a potential change in the heart tissue. In the SLE group, 5 cases were positive for antiphospholipid (APS) Abs, while 7 cases were positive for either anti-SS-A or anti-RNP Abs. Only 2 cases had elevated preoperative anti-DNA Ab and complement reduction. Of the SLE complication group, 2 of the 9 cases were negative for all Abs but IgG deposits were observed in a case. Of these 4 cases were selected and stained with anti-IgM, anti-C3 and anti-NE Abs. However IgM and C3 deposits were only observed in one patient who developed myocardial infarction at the age of 39 and was triple positive for APS, anti-SS-A and anti-RNP Abs (Figure 1b). There were also no NE deposits in any of the cases. Even if complement and anti-DNA Ab levels in the serum are normal, attention should be paid to heart disease complications during the long-term observation of SLE patients. In particular, attention should be paid to various autoantibody-positive cases such as APS, anti-SS-A Ab and anti-RNP Ab. The anti-NE Ab was not stained in this study because the tissue was different from the lesion site and because it occurred during the chronic course.

Conclusion

In SLE patients who developed cardiovascular lesions and required surgery, immunological abnormalities may occur in the myocardial tissue even if serum complement and anti-DNA Ab levels are stable.

References

[1]Stephane Zuily et al. Valvular Curr Rheumatol Rep (2013) 15:320.

[2]Zawadowski GM et al. Lupus. 2012;21(13):1378-84.

[3]Daniel Appelgren et al. Autoimmunity 2018,vol51,No.6,310-318.

Disclosure of Interests

None declared

[A case of unresectable intrahepatic cholangiocarcinoma receiving sustainable pembrolizumab therapy]

A 65-year-old man had unresectable intrahepatic cholangiocarcinoma with a malignant biliary stricture. We used an endoscopic plastic stent to drain the bile. Despite receiving standard chemotherapy, the tumor eventually progressed and cancerous peritonitis developed. We had to exchange plastic stents frequently because of stent occlusion. We had a re-biopsy with EUS-FNA and tested for microsatellite instability, which came back as MSI-high. We administered pembrolizumab, which resulted in a significant reduction of tumor size. We were able to administer long-term chemotherapy without serious side effects by repeatedly exchanging plastic stents for stent occlusion. He has maintained partial response for more than 20 months after receiving pembrolizumab.

Anti-PD-1 antibody monotherapy versus anti-PD-1 plus anti-CTLA-4 combination therapy as first-line immunotherapy in unresectable or metastatic mucosal melanoma: a retrospective, multicenter study of 329 Japanese cases (JMAC study)

Background

Anti-programmed cell death protein 1 (PD-1) antibody monotherapy (PD1) has led to favorable responses in advanced non-acral cutaneous melanoma among Caucasian populations; however, recent studies suggest that this therapy has limited efficacy in mucosal melanoma (MCM). Thus, advanced MCM patients are candidates for PD1 plus anti-cytotoxic T lymphocyte-associated antigen-4 (CTLA-4) combination therapy (PD1 + CTLA4). Data on the efficacy of immunotherapy in MCM, however, are limited. We aimed to compare the efficacies of PD1 and PD1 + CTLA4 in Japanese advanced MCM patients.

Patients and methods

We retrospectively assessed advanced MCM patients treated with PD1 or PD1 + CTLA4 at 24 Japanese institutions. Patient baseline characteristics, clinical responses (RECIST), progression-free survival (PFS), and overall survival (OS) were estimated using Kaplan–Meier analysis, and toxicity was assessed to estimate the efficacy and safety of PD1 and PD1 + CTLA4.

Results

Altogether, 329 patients with advanced MCM were included in this study. PD1 and PD1 + CTLA4 were used in 263 and 66 patients, respectively. Baseline characteristics were similar between both treatment groups, except for age (median age 71 versus 65 years; P < 0.001). No significant differences were observed between the PD1 and PD1 + CTLA4 groups with respect to objective response rate (26% versus 29%; P = 0.26) or PFS and OS (median PFS 5.9 months versus 6.8 months; P = 0.55, median OS 20.4 months versus 20.1 months; P = 0.55). Cox multivariate survival analysis revealed that PD1 + CTLA4 did not prolong PFS and OS (PFS: hazard ratio 0.83, 95% confidence interval 0.58-1.19, P = 0.30; OS: HR 0.89, 95% confidence interval 0.57-1.38, P = 0.59). The rate of ≥grade 3 immune-related adverse events was higher in the PD1 + CTLA4 group than in the PD1 group (53% versus 17%; P < 0.001).

Conclusions

First-line PD1 + CTLA4 demonstrated comparable clinical efficacy to PD1 in Japanese MCM patients, but with a higher rate of immune-related adverse events.

•

Anti-PD-1 plus anti-CTLA-4 antibody therapy (PD1 + CTLA4) is an option for patients with advanced mucosal melanoma (MCM).

•

Data on the efficacy of PD1 + CTLA4 compared with PD-1 monotherapy (PD1) for MCM, however, are limited.

•

We retrospectively analyzed data from 329 Japanese patients with advanced MCM treated with PD1 or PD1 + CTLA4.

•

No significant differences in objective response rate, progression-free survival, or overall survival were observed.

•

Immune-related adverse events resulting in treatment cessation were higher in the PD1 + CTLA4 group.

POS0516 REDEFINING THE CLINICAL AND LABORATORY FEATURES OF RHEUMATIC PLEURAL EFFUSION: A 30-CASE SERIES

Background:

Rheumatoid pleural effusion (RPE) is a common extra-articular complication in patients with rheumatoid arthritis (RA). Previous studies have shown that RPE usually occurs in middle-aged men with rheumatoid factor (RF)-positive RA. RPE usually has features of pleural fluid acidosis, high lactate dehydrogenase (LDH) levels, and very low glucose levels(1). However, to the best of our knowledge, these findings were based on very few case series and reports, and most of these reports were published by the early 2000s(1, 2).

Objectives:

To investigate the clinical and laboratory characteristics and typical clinical courses of patients with RPE in a single centre of Japan since the beginning of the 21st century.

Methods:

Medical records of RPE patients were retrospectively reviewed between May 2006 and September 2020. RPE was identified by fulfilling these five conditions: (1) confirmation of the RA diagnosis; (2) having an exudative pleural effusion according to Light’s criteria; (3) negative results of pleural fluid culture; (4) negative results of pleural fluid cytology; and (5) exclusion of a parapneumonic effusion or empyema defined as no antibiotic use or ineffectiveness of antibiotics during the clinical course. Patients were divided into two groups according to their age at diagnosis: <60 years (Group A) and ≥60 years (Group B).

Results:

A total of 30 cases of RPE were included in the study. The median age was 71 years (interquartile range [IQR], 66–78 years). Of these patients, 16 (53%) were women. The median disease duration of RA was 98 months (IQR, 8–162 months). The two groups comprised six patients aged <60 years old and 24 patients ≥60 years. The median age was 54 years (IQR, 49–56 years) in Group A and 74 years (IQR, 69–78 years) in Group B. The median disease duration of RA was longer in Group B than that in Group A (132 vs. 3 months, p=0.008). Compared with Group A, Group B had fewer patients with fever (14% vs. 83%, p=0.003), and had lower serum C-reactive protein levels (3.3 vs. 11.1 mg/dL, p=0.03). Moreover, Group B was more likely to show mild inflammatory pleural fluids with higher pH (7.5 vs. 7.2, p=0.005) and lower LDH levels (155 vs. 1810 IU/L, p=0.046). Corticosteroids were started or increased in five (83%) and nine (38%) patients, and biologic disease-modifying anti-rheumatic drugs were started in one (17%) and two (8%) patients in groups A and B, respectively. One patient (16%) died within 5-years in Group A, and seven patients (29%) died in Group B.

Conclusion:

In contrast to previous studies, RPE was seen in older patients as well as middle-aged adults, and the pleural fluid analysis in older patients with RPE showed milder inflammation than the middle-aged patients.

References:

[1]Balbir-Gurman A, et al. Semin Arthritis Rheum. 2006 Jun; 35(6): 368-78.

[2]Faurschou P, et al. Thorax. 1985 May; 40(5): 371-5.

Table 1.

Comparison of clinical and laboratory findings between Group A and Group B.

Group A (n=6)Group B (n=24)P valueAge (years)54 [49-56]74 [69-78]Female2 (n=6, 33.3)14 (n=24, 58.3)0.38Disease duration of RA (months)3 [1-9]132 [44-199]0.008Fever ≥37.0°C5 (n=6, 83.3)3 (n=22, 13.6)0.003SerumCRP (mg/dL)11.1 [5.6-1.4]3.3 [0.9-10.5]0.03  RF (IU/mL)100 [19-816]63 [23-193]0.95  Anti-CCP ab positive5 (n=6, 83.3)12 (n=15, 80)1.00Pleural fluid analysispH7.2 [7.2-7.2]7.5 [7.4-7.5]0.005LDH (IU/L)1810 [594-2932]155 [123-346]0.046Glu (mg/dL)59 [10-123]105 [91-122]0.42Tp (g/dL)5.1 [4.9-5.6]4.6 [3.6-5.2]0.21Number of cells (/μL)5235 [3353-9300]3300 [1490-5008]0.27 Glu/serum Glu0.41 [0.09-0.99]1.05 [0.85-1.15]0.71Started or increased CS5 (n=6, 83.3)9 (n=24, 37.5)0.18Started bDMARDs1 (n=6, 16.6)2 (n=24, 8.3)0.50Died within 5 years1 (n=6, 16.6)7 (n=24, 29.1)1.00

Data are median [interquartile range], or number (total number, percent).

Abbreviations: RA, rheumatoid arthritis; CRP, C-reactive protein; RF, rheumatoid factor; Anti-CCP ab, anti-cyclic citrullinated peptide antibodies; LDH, lactate dehydrogenase; Glu, glucose; Tp, total protein; CS, corticosteroid; bDMARDs, biologic disease-modifying anti-rheumatic drugs

Disclosure of Interests:

None declared

Does methotrexate have no beneficial effect in reducing flares in the treatment of polymyalgia rheumatica patients?

We read the article by Marsman et al. regarding the efficacy of methotrexate (MTX) in the treatment of polymyalgia rheumatica (PMR) with great interest. This study added new insights regarding the use of MTX in a real-world clinical setting and its effect on the incidence rates of flares. However, we would like to voice our concerns regarding the definition of the participants and interventions that were performed in the study, as well as the comparability of the intervention and control groups. Our concerns include the possibility of the inadvertent enrollment of patients with rheumatoid arthritis in a study on PMR, a lack of a clear definition of glucocorticoid ineffectiveness, a lack of adjustment of glucocorticoid dosages, and a reliance on the judgement of individual medical providers rather than clearly defined investigative guidelines in the study procedures. To summarize, we would like to voice concerns about how and to whom MTX was prescribed, as well as the definition of the control group. These revisions and modifications would clarify the importance of the results regarding the efficacy of MTX administration in the treatment of PMR.

Levels of phospholipids and triacylglycerol-containing omega 3 fatty acids in myocardial tissue of patients with myocardial infarction: analyzed by a lipidomics profiling method

Objective

According to population-based studies, low omega 3 fatty acid (omega3FA) intake and high levels of serum triacylglycerol (TAG) are associated with cardiovascular diseases. Recent advances in mass spectrometry allow molecular lipid (lipidomics) profiling, which may enhance cardiovascular risk prediction. In this study, we assessed the levels of omega3FA-containing phospholipids (PL) and TAG in myocardial tissues of patients with and without myocardial infarction (MI) using a lipidomics profiling method.

Methods

We performed lipidomics profiling of human left atrial appendage (LAA) tissue of 29 consecutive patients receiving off-pump coronary bypass surgery with standard LAA resection. The patients were divided into the MI group (n=7) and an age- and gender-matched non-MI group (n=7).

Results

Lipidomics profiling revealed that the MI group tended to have low levels of phosphatidylcholines (PC), phosphatidylethanolamine (PE), lysophosphatidylethanolamine (LPE), and plasmalogen, and high levels of TAG species. Individual molecular species containing omega3FA, such as PC (18:0/20:5; 3,200±1,200 vs. 4,500±910 pmol/g tissue, p=0.04) and plasmalogen (18:1/20:5; 57,000±21,000 vs. 91,000±28,000 pmol/g tissue, p=0.02), were significantly lower in the MI group than in the non-MI group.

Conclusions

To our knowledge, this is the first study to determine the levels of omega3FA-containing PL and TAG in myocardial tissue using lipidomics profiling. We discovered that lower levels of omega3FA-containing PL and higher levels of TAG existed in myocardial tissues of patients with MI than in those of patients without MI. Accordingly, the lipidomics profiling method for human myocardial tissue may be useful for developing therapy targets for cardiovascular diseases.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): MEXT/JSPS KAKENHI Grant

Lupus Aortitis Successfully Treated with Moderate-dose Glucocorticoids: A Case Report and Review of the Literature

Lupus aortitis is a rare and potentially life-threatening disorder. Previous studies have reported the utility of high-dose systemic glucocorticoids or surgery as the treatment, although there have been no related controlled trials. We herein report a 49-year-old woman with a 35-year history of systemic lupus erythematosus who was diagnosed with aortitis. Her symptoms and laboratory and imaging abnormalities rapidly resolved upon the administration of moderate-dose glucocorticoids. We subsequently performed a literature review of similar cases to identify the appropriate treatment and discuss these cases. A study of further cases will be needed to identify the characteristics of patients who would benefit from moderate-dose glucocorticoid therapy.

Induction of adaptive immune responses against antigens incorporated within the capsid of simian virus 40

Simian virus 40 (SV40) is a monkey polyomavirus. The capsid structure is icosahedral and comprises VP1 units that measure 45 nm in diameter. Five SV40 VP1 molecules form one pentamer subunit, and a single icosahedral subunit comprises 72 pentamers; a single SV40 VP1 capsid comprises 360 SV40 VP1 molecules. In a previous study, we showed that an influenza A virus matrix protein 1 (M1) CTL epitope inserted within SV40 virus-like particles (VLPs) induced cytotoxic T lymphocytes (CTLs) without the need for an adjuvant. Here, to address whether SV40 VLPs induce adaptive immune responses against VLP-incorporated antigens, we prepared SV40 VLPs containing M1 or chicken ovalbumin (OVA). This was done by fusing M1 or OVA with the carboxyl terminus of SV40 VP2 and co-expressing them with SV40 VP1 in insect cells using a baculovirus vector. Intraperitoneal (i.p.) or intranasal administration of SV40 VLPs incorporating M1 induced the production of CTLs specific for the M1 epitope without the requirement for adjuvant. The production of antibodies against SV40 VLPs was also induced by i.p. administration of SV40 VLPs in the absence of adjuvant. Finally, the administration of SV40 VLPs incorporating OVA induced anti-OVA antibodies in the absence of adjuvant; in addition, the level of antibody production was comparable with that after i.p. administration of OVA plus alum adjuvant. These results suggest that the SV40 capsid incorporating foreign antigens can be used as a vaccine platform to induce adaptive immune responses without the need for adjuvant.

Anti-PD1 checkpoint inhibitor therapy in acral melanoma: a multicenter study of 193 Japanese patients

BACKGROUND

Acral melanoma (AM) is an epidemiologically and molecularly distinct entity that is underrepresented in clinical trials on immunotherapy in melanoma. We aimed to analyze the efficacy of anti-programmed cell death 1 (anti-PD-1) antibodies in advanced AM.

PATIENTS AND METHODS

We retrospectively evaluated unresectable stage III or stage IV AM patients treated with an anti-PD-1 antibody in any line at 21 Japanese institutions between 2014 and 2018. The clinicobiologic characteristics, objective response rate (ORR, RECIST), survival estimated using Kaplan-Meier analysis, and toxicity (Common Terminology Criteria for Adverse Events 4.0.) were analyzed to estimate the efficacy of the anti-PD-1 antibodies.

RESULTS

In total, 193 patients (nail apparatus, 70; palm and sole, 123) were included in the study. Anti-PD-1 antibody was used as first-line therapy in 143 patients (74.1%). Baseline lactate dehydrogenase (LDH) was within the normal concentration in 102 patients (52.8%). The ORR of all patients was 16.6% (complete response, 3.1%; partial response, 13.5%), and the median overall survival (OS) was 18.1 months. Normal LDH concentrations showed a significantly stronger association with better OS than abnormal concentrations (median OS 24.9 versus 10.7 months; P < 0.001). Although baseline characteristics were similar between the nail apparatus and the palm and sole groups, ORR was significantly lower in the nail apparatus group [6/70 patients (8.6%) versus 26/123 patients (21.1%); P = 0.026]. Moreover, the median OS in this group was significantly poorer (12.8 versus 22.3 months; P = 0.03).

CONCLUSIONS

Anti-PD-1 antibodies have limited efficacy in AM patients. Notably, patients with nail apparatus melanoma had poorer response and survival, making nail apparatus melanoma a strong candidate for further research on the efficacy of novel combination therapies with immune checkpoint inhibitors.

The efficacy of eribulin mesylate for patients with cutaneous angiosarcoma previously treated with taxane: a multicentre prospective observational study

BACKGROUND

Taxanes are the current first-line treatment for advanced cutaneous angiosarcoma (CAS) for patients who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity. However, no effective second-line therapy for such patients has been established.

METHODS

We designed a single-arm prospective observational study of eribulin mesylate (ERB) administered at a dose of 1·4 mg m^-2 on days 1 and 8 in a 21-day cycle. Patients with advanced CAS who were previously treated with a taxane and were scheduled to begin ERB treatment were enrolled. The primary endpoint was overall survival (OS) and the secondary endpoints were response rate (RR), progression-free survival (PFS) and toxicity assessment.

RESULTS

We enrolled a total of 25 patients. The median OS and PFS were 8·6 months and 3·0 months, respectively. The best overall RR was 20% (five of 25). In total, 16 grade 3/4 severe adverse events (SAEs) occurred; however, all patients recovered. Patients who achieved partial response or stable disease as best response had longer OS than those with progressive disease (median OS not reached and 3·3 months, respectively; P < 0·001). Patients who did not experience SAEs showed longer OS than those who did (median OS 18·8 months and 7·5 months, respectively; P < 0·05). Patients with distant metastasis had shorter median OS than those with locoregional disease, but without statistically significant difference.

CONCLUSIONS

ERB showed a promising RR and is a potential candidate for second-line treatment for patients with CAS, after treatment with taxanes. However, owing to the occurrence of SAEs in over half of the participants, caution should be exercised regarding ERB use in elderly patients. What is already known about this topic? Taxanes are the current first-line treatment for patients with advanced cutaneous angiosarcoma (CAS) who are considered difficult to treat with doxorubicin owing to advanced age or comorbidity. No effective therapy for taxane-resistant CAS has been established thus far. Eribulin suppresses microtubule polymerization and elicits an antitumour effect similar to that of taxanes. What does this study add? In our single-arm prospective observational study to evaluate the efficacy of eribulin for treating patients with advanced CAS who previously received taxanes, the median overall survival and progression-free survival were 8·6 and 3·0 months, respectively. Response rates at weeks 7, 13 and 25 were 20%, 17% and 14%, respectively. Although 16 grade 3/4 severe adverse events occurred, all patients recovered. Eribulin showed a promising response rate and is a potential candidate for second-line treatment in CAS after taxane treatment. Linked Comment: Smrke and Benson. Br J Dermatol 2020; 183:797-798.

2-mm surgical margins are adequate for most basal cell carcinomas in Japanese: a retrospective multicentre study on 1000 basal cell carcinomas

BACKGROUND

Surgery is the gold standard for basal cell carcinomas (BCC). Current recommended surgical margins for BCCs are determined from studies in Caucasian populations. However, the appropriate surgical margins for BCCs in non-white races are unclear.

OBJECTIVES

To investigate the accuracy of preoperative determination of clinical tumour borders and appropriate surgical margins in Japanese patients with BCC.

METHODS

The maximum calculated differences in distance between the preoperatively determined surgical margins and the actual histologic tumour side margins were considered as 'accuracy gaps' of clinical tumour borders. Estimated side margin positivity rates (ESMPRs) with narrower (2 and 3 mm) surgical margins were calculated on the basis of the accuracy gaps.

RESULTS

Overall, 1000 surgically excised BCCs from 980 Japanese patients were included. The most frequent histologic subtype was nodular BCC (67%). The median accuracy gap was 0.3 mm [interquartile range (IQR): -0.5 to +1 mm]. The ESMPRs with 2- and 3-mm surgical margins were 3.8% and 1.4%, respectively. Only the ESMPRs between the well-defined (n = 921) and poorly defined clinical tumour border groups (n = 79) showed statistical difference [2-mm margin: 3.1% vs. 11.7%, OR: 3.89, 95% confidential interval (CI): 1.41-10.71, P <0.01; 3-mm margin: 0.97% vs. 6.3%, OR: 6.58, 95% CI: 1.67-25.99, P <0.01]. No significant differences in ESMPRs were noted in other subgroups including risk classifications.

CONCLUSIONS

The determined clinical tumour border accuracy gaps in this Japanese cohort were negligible. Dermatologic surgeons may use narrower surgical margins with acceptable margin positivity rates. The clarity of clinical tumour borders could be an appropriate guide for selection of different surgical margins in the Japanese cohort.

P2861Elevated cc chemokine receptor 2 expression and higher migratory activity of monocytes in atrial fibrillation patients with progressive structural remodeling

Background

Inflammation in atrial tissue underlies structural remodeling of left atrium, which is a hallmark of atrial fibrillation (AF). Activated monocytes mediate inflammation; however, the role of monocytes in AF pathogenesis has not been extensively examined. In this study, we thus investigated the association between structural remodeling of left atrium, represented by left atrial dimension (LAD), and characteristics of peripheral monocytes in patients with AF.

Methods

Blood samples were collected from patients undergone catheter ablation between July 2017 and October 2018, including AF patients (n=152) and paroxysmal supraventricular tachycardia (PSVT) patients, which serves as a control non-AF group (n=22). AF patients were further divided into two groups by the median of LAD (normal LAD group: LAD <40 mm, n=77, large LAD group: LAD ≥40 mm, n=75). Peripheral blood mononuclear cells (PBMC) were isolated to analyze monocyte subsets by flow cytometry. In a subset of patients, we further isolated monocytes from PBMC by using magnetic bead-based negative selection method then gene products associated with inflammation or monocyte functions were evaluated. We also examined migratory activity of monocytes toward monocyte chemotactic protein-1, a ligand for CC chemokine receptor 2 (CCR2), using a modified Boyden chamber method. Finally, we performed immunofluorescence staining of monocytes and macrophages in left atrial appendages resected from patients underwent coronary bypass graft surgery (CABG) complicated by AF.

Results

There were no differences in age, body mass index and high-sensitivity C-reactive protein levels among three groups, including non-AF, normal LAD and large LAD groups, except that more female subjects were included in non-AF group. We found that proportions of classical CD14++CD16- and nonclassical CD14+CD16++ monocytes were higher (non-AF: 71.2±7.3% vs. AF: 75.5±8.3%, p<0.05) and lower (non-AF: 16.4±5.9% vs. AF: 13.2±5.5%, p<0.05), respectively, in all AF patients compared with those in non-AF group, while no significant difference was observed between normal and large LAD groups. In monocytes from large LAD group, mRNA levels of CCR2, a receptor to mediate monocyte chemotaxis, were significantly higher compared to those in normal LAD group (Figure A, p<0.05). Furthermore, monocytes isolated from large LAD group exhibited higher migratory capacity compared to normal LAD group (Figure B, p<0.01). Finally, higher monocyte/macrophage infiltrations to left atrial appendages were implicated in patients with large LAD, shown by immunofluorescence staining.

Conclusions

Monocytes in AF patients with enlarged left atrium expressed higher CCR2 mRNA and were more active in chemotaxis to MCP-1, suggesting the proactive roles of activated monocytes in the pathogenesis of arterial remolding in AF.

P629Voluntary exercise associated with myokine production ameliorates cardiac remodeling and inflammation in a myocardial infarction mouse model

Background

Left ventricular (LV) remodeling, through excessive inflammation, leads to heart failure. Exercise (Ex) training is associated with a risk reduction in heart failure through direct and indirect mechanisms by which Ex contributes an anti-inflammatory effect. During Ex, contracting muscle fibers release myokines, including interleukins (ILs), tumor necrosis factor α (TNF-α), follistatin-like protein 1 (FSTL-1), and fibroblast growth factor 21 (FGF-21), into the bloodstream. These myokines may have beneficial effects on other damaged organs, such as an infarcted myocardium, through anti-inflammatory effects. However, the exact mechanisms of the anti-inflammatory effects of voluntary Ex in myocardial infarction (MI) are poorly understood. Therefore, we investigated the effect of voluntary Ex on cardiac remodeling and inflammation, the relationship between cardiac remodeling and skeletal muscle (SKM) response, and circulating myokine levels in a mouse model of MI.

Methods

Twelve-week-old male C57BL/6J mice were used and divided into the following 4 groups: sham operation (Sham), MI, Sham+Ex, and MI+Ex. MI was induced by ligation of the left anterior descending coronary artery. Ex groups began voluntary wheel running for 4 weeks after the operation. An echocardiography was performed at baseline and 4 weeks after the operation. The mRNA levels in the LV infarcted area and SKM were measured with RT-PCR and western blot analysis. Plasma levels of myokines were also measured with immunoassays.

Results

Four weeks after MI induction, echocardiographic evaluation showed that the MI mice had a larger LV end-diastolic diameter (LVEDD) and end-systolic diameter (LVESD) than the Sham mice. The MI mice also showed higher mRNA levels of TNF-α, IL-1β, IL-6, and IL-10 in the LV tissue when compared to the Sham mice. These changes were significantly ameliorated in the MI+Ex mice. Interestingly, in the MI+Ex mice, mRNA levels of IL-6, IL-1β, FSTL-1, and FGF-21 in the SKM were significantly higher than in the MI mice, while there were no significant differences in TNF-α and IL-10 levels in all groups. Similarly, protein expression levels of peroxisome proliferator-activated receptor gamma coactivator 1-alpha, sirtuin-1, and mitochondrial transcriptional factor A of mitochondrial function markers in SKM were also significantly higher in the MI+Ex mice than in the MI mice. Furthermore, there were significant correlations between plasma levels of IL-1β, but not other myokines, and LVEDD, and LVESD. In addition, there was also a significant correlation between the SKM IL-1β level and LVESD in the Sham+Ex mice (all, P<0.05).

Conclusions

Amelioration of cardiac remodeling and inflammation by voluntary Ex is associated with increased myokines, especially IL-1β, in a MI mouse model. These results suggest that increased myokine levels, through voluntary exercise, may play an important role in the prevention of cardiac remodeling after MI.

Dopamine regulates cytokine secretion during innate and adaptive immune responses

Dopamine (DA) is synthesized by various immune cells. DA receptors (DARs), which comprise five isoforms, are expressed on the surface of these cells. Therefore, it is likely that DA plays a role in regulating innate and adaptive responses. However, the underlying molecular mechanism(s) is largely unknown. Here, we found that, during innate immune responses, DA suppressed secretion of IFN-γ, TNF-α and IL-1β, but promoted secretion of IL-10 and CXCL1 by lipopolysaccharide (LPS)-stimulated mouse splenocytes, suggesting that DA regulates cytokine secretion. Immune subset studies indicated that DA suppressed secretion of IFN-γ, TNF-α and IL-1β by NK cells, as well as secretion of TNF-α by neutrophils and monocytes; however, DA up-regulated IL-10 secretion by neutrophils, monocytes, B cells, macrophages (Mφs) and dendritic cells within the splenocyte population. In addition, DA up-regulated secretion of CXCL1 by LPS-stimulated NK cells and Mφs. Meanwhile, treatment with DAR agonists or antagonists suppressed secretion of inflammatory cytokines from LPS-stimulated splenocytes. Pre-treatment of LPS-stimulated splenocytes with the PI3K inhibitor wortmannin reversed DA-mediated suppression of IFN-γ secretion, indicating that DA regulates IFN-γ secretion via the inositol 1,4,5-trisphosphate signaling pathway in these cells. Administration of DA and LPS to mice immunized with chicken ovalbumin (OVA) increased secretion of IL-5 by mouse lung lymphocytes, suggesting that DA promotes OVA-specific Th2-mediated immune responses by these cells. Taken together, these findings indicate that DA regulates cytokine secretion during innate and adaptive immune responses.

Identification of the novel 3' UTR sequences of human IL-21 mRNA as potential targets of miRNAs

Hepatitis B virus (HBV) infection is a leading cause of hepatocellular carcinoma worldwide. However, the strategy of HBV to escape from the host immune system remains largely unknown. In this study, we examined extracellular vesicles (EVs) secreted from human hepatocytes infected with HBV. EVs includeing exosomes are nano-size vesicles with proteins, mRNAs, and microRNAs (miRNAs), which can be transmitted to different cells. We found that 104 EV associated miRNAs were increased in hepatocytes more than 2-fold by HBV infection. We then selected those that were potentially implicated in immune regulation. Among them, five HBV-induced miRNAs were found to potentially target multiple sequences in the 3'UTR of IL-21, a cytokine that induces anti-viral immunity. Moreover, expression of a reporter gene with the 3' UTR of human IL-21 mRNA was suppressed by the five miRNAs individually. Finally, IL-21 expression in cloned human T cells was down-regulated by the five miRNAs. Collectively, this study identified the novel 3' UTR sequences of human IL-21 mRNA and potential binding sites of HBV-induced EV-miRNAs.

Epispadias and the associated embryopathies: genetic and developmental basis

The abnormalities in the urogenital organs are frequently observed as human developmental diseases. Among such diseases, the defects in the upper part of external genitalia are rather rare named epispadias. The cleft in the dorsal part of external genitalia often reaches to the urethra. In general, the urogenital abnormalities accompany defects in the adjacent tissues and organs. The ventral body wall and bladder can also be affected in the patients with dorsal defects of the external genitalia. Therefore, such multiple malformations are often classified as bladder exstrophy and epispadias complex (BEEC). Because of the lower frequency of such birth defects and their early embryonic development, animal models are required to analyze the pathogenic mechanisms and the functions of responsible genes. Mutant mouse analyses on various signal cascades for external genitalia and body wall development are increasingly performed. The genetic interactions between growth factors such as bone morphogenetic proteins (Bmp) and transcription factors such as Msx1/2 and Isl1 have been suggested to play roles for such organogenesis. The significance of epithelial-mesenchymal interaction (EMI) is suggested during development. In this review, we describe on such local interactions and developmental regulators. We also introduce some mutant mouse models displaying external genitalia-body wall abnormalities.

Identification and functional activity of a staphylocoagulase type XI variant originating from staphylococcal food poisoning isolates

Staphylocoagulase, an extracellular protein secreted by Staphylococcus aureus, has been used as an epidemiological marker. At least 12 serotypes and 24 genotypes subdivided on the basis of nucleotide sequence have been reported to date. In this study, we identified a novel staphylocoagulase nucleotide sequence, coa310, from staphylococcal food poisoning isolates that had the ability to coagulate plasma, but could not be typed using the conventional method. The protein encoded by coa310 contained the six fundamental conserved domains of staphylocoagulase. The full-length nucleotide sequence of coa310 shared the highest similarity (77·5%) with that of staphylocoagulase-type (SCT) XIa. The sequence of the D1 region, which would be responsible for the determination of SCT, shared the highest similarity (91·8%) with that of SCT XIa. These results suggest that coa310 is a novel variant of SCT XI. Moreover, we demonstrated that coa310 encodes a functioning coagulase, by confirming the coagulating activity of the recombinant protein expressed from coa310. This is the first study to directly demonstrate that Coa310, a putative SCT XI, has coagulating activity. These findings may be useful for the improvement of the staphylocoagulase-typing method, including serotyping and genotyping.

SIGNIFICANCE AND IMPACT OF THE STUDY

This is the first study to identify a novel variant of staphylocoagulase type XI based on its nucleotide sequence and to demonstrate coagulating activity in the variant using a recombinant protein. Elucidation of the variety of staphylocoagulases will provide suggestions for further improvement of the staphylocoagulase-typing method and contribute to our understanding of the epidemiologic characterization of Staphylococcus aureus.

Peripheral circulation evaluation with near-infrared spectroscopy in skeletal muscle during cardiopulmonary bypass

Background:

We designed a non-invasive, observational, real-time study, using near-infrared spectroscopy (NIRS) to assess the in vivo effects of cardiopulmonary bypass (CPB) on patients’ skeletal muscle as well as the effects of hemodilution and hypothermia on tissue oxygen delivery during CPB.

Methods:

The study included 20 consecutive adult patients undergoing open-heart surgery with CPB. Evaluation parameters for peripheral circulation were measured using the NIRO-200NX and recorded every 30 seconds. To assess how hemodilution influences peripheral circulation parameters, we compared data between a group of patients with hematocrit (Hct) values >22% (high Hct group) and those with Hct values ⩽22% (low Hct group).

Results:

Changes in the concentration of oxygenated hemoglobin (ΔO2Hb, μmol/L), which flows into the skeletal muscle, was an important factor for deciding the tissue oxygenation index (TOI%), showing the tissue oxygen saturation. The low Hct group showed a significant increase in the normalized tissue hemoglobin index (nTHI), showing the percentage change in the amount of initial hemoglobin and TOI compared to the high Hct group. Changes in the concentration of oxygenated hemoglobin (ΔO2Hb, μmol/L) and deoxygenated hemoglobin (ΔHHb, μmol/L) were significantly less in the low Hct group than in the high Hct group, thus, showing good peripheral circulation despite the low hematocrit levels.

Conclusion:

Our study indicated the presence of a compensatory mechanism in which increased blood flow of the microcirculation is in compensation for the lack of oxyhemoglobin delivery caused by hemodilution.