Tumor immunoevasion via acidosis-dependent induction of regulatory tumor-associated macrophages.

Many tumors evolve sophisticated strategies to evade the immune system, and these represent major obstacles for efficient antitumor immune responses. Here we explored a molecular mechanism of metabolic communication deployed by highly glycolytic tumors for immunoevasion. In contrast to colon adenocarcinomas, melanomas showed comparatively high glycolytic activity, which resulted in high acidification of the tumor microenvironment. This tumor acidosis induced Gprotein-coupled receptor-dependent expression of the transcriptional repressor ICER in tumor-associated macrophages that led to their functional polarization toward a non-inflammatory phenotype and promoted tumor growth. Collectively, our findings identify a molecular mechanism of metabolic communication between non-lymphoid tissue and the immune system that was exploited by high-glycolytic-rate tumors for evasion of the immune system.

Hidradenitis Suppurativa Is Associated with Severe Sexual Impairment.

INTRODUCTION: Hidradenitis suppurativa (HS) is a chronic inflammatory disorder of the pilosebaceous unit, often affecting and deforming intimate regions. HS is associated with severe pain, pruritus, and constant, purulent, malodorous discharge expected to impair sexual health of patients. METHODS: We performed a cross-sectional, multicentric study involving 199 German patients from the health services research project "Epidemiology and Care in Acne inversa (EpiCAi)." The sexual health, HS severity, and quality of life of the studied group were evaluated using a specially designed questionnaire. RESULTS: Regardless of gender, HS has an enormous impact on patients' sexual health. The patients scored, on average, 28.8 ± 5.3 points on the Relation and Sexuality Scale (RSS). Multiple linear regression revealed that females and patients with Hurley III stage had higher sexual dysfunction (p = 0.012). Sexual dysfunction is associated with pain (ß = 0.25), the number of active lesions, the affected areas (ß = 0.14), and psychosocial aspects, including low quality of life (ß = 0.404), stigmatization (ß = 0.411), depression (ß = 0.413), and anxiety (ß = 0.300). Patients already see a substantial decrease in sexual frequency in the early stages of HS, while functional impairment and fear increase with the severity of the disease. CONCLUSION: Sexual health and management of its dysfunctions should be part of a holistic approach to HS patients.

Real-world effectiveness and safety of the LAight-therapy in patients with hidradenitis suppurativa.

BACKGROUND AND OBJECTIVES: Hidradenitis suppurativa (HS)/Acne inversa (Ai) is a chronic debilitating disease with limited therapy options. The device-based LAight therapy was approved in Europe in 2017. The aim of this study was to evaluate the effect of real-world care with at least one treatment with LAight therapy on disease activity and burden in 3,437 patients. PATIENTS AND METHODS: Patients were included in the analysis if they had a diagnosis of HS and received at least one treatment. The endpoints Hidradenitis Suppurativa Severity Score System (IHS4), pain on the numeric rating scale (pain-NRS) and Dermatology Life Quality Index (DLQI) were analyzed using a linear mixed model for repeated measures (MMRM) over 26 weeks of care with LAight therapy. Furthermore, responder rates were calculated for all endpoints, and the therapy's safety profile and patient satisfaction were thoroughly examined. RESULTS: A significant decrease in IHS4, pain-NRS, and DLQI was achieved during 26 weeks of care with LAight. The BMI at baseline had a significant negative effect on therapy response for pain-NRS and DLQI. CONCLUSIONS: This study confirms that LAight therapy leads to satisfactory disease control in all stages of severity and is a valuable addition to the therapeutic repertoire of HS.

TNF-α blockade may lead to improvement of vascular function in psoriasis patients.

Psoriasis is one of the most common chronic inflammatory skin diseases and at the same time a risk factor for cardiovascular disease. Interleukin-17A (IL-17A)-mediated inflammation in psoriasis may lead to vascular dysfunction. This study aimed at investigating whether anti-inflammatory treatment by tumor necrosis factor (TNF)-α blockade alters vascular function in psoriasis patients. A total of 11 patients with psoriasis who underwent treatment with either adalimumab (n = 8) or etanercept (n = 3), 10 healthy control individuals and 14 patients with coronary artery disease (CAD) were included in this study. Treatment response was assessed using the Psoriasis Area and Severity Index (PASI) score. Endothelial reactivity and resting endothelium-dependent vascular tone were assessed by ultrasound measurement of flow-mediated dilation (FMD) and low-flow-mediated constriction (l-FMC), respectively. FMD was slightly impaired in psoriasis patients compared to healthy controls. Anti-TNF-α treatment did not significantly change FMD levels. Psoriasis patients showed a trend towards increased baseline vascular activity compared to healthy controls. Anti-TNF-α treatment significantly improved l-FMC in psoriasis patients. Noteworthy, both FMD and l-FMC in psoriasis patients were comparable to those in patients with CAD; however, an important influence of age differences between the groups or co-existent classical cardiovascular risk factors on FMD and l-FMC cannot be ruled out by our small study. The results suggest that anti-inflammatory treatment with TNF-α blockade improves vascular function in patients with psoriasis, mainly by altering baseline vascular tone. Further studies will be necessary to establish the potentially protective impact of anti-inflammatory therapy on vascular function in patients with chronic inflammatory diseases.

LAight® Therapy Is an Effective Treatment Option to Maintain Long-Term Remission of Hurley I and II Hidradenitis Suppurativa: Results from Period B of RELIEVE, a Multicenter Randomized, Controlled Trial.

BACKGROUND: Hidradenitis suppurativa is a chronic, inflammatory, burdensome skin disease where current first-line treatments are limited to topical and/or systemic antibiotics which cannot be applied for long-term disease management. Period B of the RELIEVE study analyzes whether LAight® therapy can sustain or even increase remission after a first topical antibiotic treatment cycle. METHODS: The RELIEVE study was performed as a two-period multicenter randomized controlled trial with blinded assessment. For period A from week 0 to week 16, the 88 participating Hurley I and II patients were randomized to either a group receiving topical clindamycin 1% solution combined with 8 additional bi-weekly treatments with LAight® therapy (group TC + L) or a group which was treated with topical clindamycin 1% solution only (group TC). After 16 weeks, patients entered open-label period B and both groups were treated exclusively with LAight® therapy for an additional 16 weeks (8 sessions, group TC + L/L and group TC/L). RESULTS: In total, 88 patients were enrolled in RELIEVE. Seventy-eight patients entered period B; 39 belonged to group TC + L/L and 39 to group TC/L. The IHS4-response at the start of period B was 62% (group TC + L/L) and 33% (group TC + L). During the 16 weeks of additional monotherapy with LAight, in both groups >90% of patients who responded to therapy in period A maintained their IHS4-response at week 32. IHS4 response rates continued to rise up to 79% of the TC + L/L group and up to 71% of the TC/L group during period B at week 32. Achievement of HiSCR and certain patient reported outcomes confirmed primary endpoint results. CONCLUSION: LAight® therapy is an effective approved therapy option for Hurley I and II HS that can be used continuously to maintain treatment success. During 16 weeks of follow-up in period B, over 90% of patients with response after period A maintained their treatment outcome, while more than 60% of prior nonresponders gained response. The fact that LAight® therapy can be applied continuously, is very effective and is well tolerated makes it a valuable treatment tool in the design of HS long-term treatment modalities.

LAight® Therapy Significantly Enhances Treatment Efficacy of 16 Weeks of Topical Clindamycin Solution in Hurley I and II Hidradenitis Suppurativa: Results from Period A of RELIEVE, a Multicenter Randomized, Controlled Trial.

BACKGROUND: Hidradenitis suppurativa (HS) is a chronic, inflammatory, burdensome skin disease where medical first-line treatment is still limited to long-term, topical and/or systemic antibiotics. The RELIEVE study aimed at evaluating the efficacy of LAight® therapy - a combination of intense pulsed light and radiofrequency - as an adjunct treatment to first-line therapies in Hurley stage I and II HS. METHODS: The RELIEVE study was performed as a two-period multicenter randomized controlled trial with blinded assessment. For period A from week 0 to week 16, the 88 participating subjects were randomized into either an intervention group (IG) or a control group (CG). The IG received topical clindamycin 1% solution combined with 8 additional bi-weekly treatments with LAight® therapy. The CG was treated with topical clindamycin 1% solution only. After 16 weeks, patients entered open-label period B and both groups were treated exclusively with LAight® therapy for an additional 16 weeks (8 sessions). The primary efficacy endpoint was the change in International Hidradenitis Suppurativa Score System (∆IHS4) at week 16 to baseline. Secondary endpoints were DLQI, HiSCR, Pain-NRS, and HADS. RESULTS: In total, from the 88 patients enrolled in RELIEVE, 81 patients were included in the endpoint analysis after period A. After 16 weeks of treatment, the ∆IHS4 of the group treated with the combination of LAight® therapy and topical clindamycin 1% solution was -7.2 ± 6.7 (-60.0%), which was significantly higher in magnitude than the ∆IHS4 in the group treated with clindamycin 1% solution alone (-1.8 ± 5.6, -17.8%, p < 0.001). Secondary endpoints, including other clinical scores as well as patient-reported outcomes, confirmed that the efficacy of the combined treatment was superior to monotherapy. CONCLUSION: The results of the primary endpoint analysis of period A of the RELIEVE study show that the combined therapy with LAight® and topical clindamycin 1% solution, resulted in a significantly higher decrease in disease severity and an improvement of quality of life in comparison to topical clindamycin 1% solution monotherapy. Treatment was well tolerated, and side effects were all mild and transitory. These data speak for the implementation of the combined treatment as a first-line therapy in Hurley stage I and II HS. LAight® therapy as long-term monotherapy (results from period B), will be analyzed in a consecutive paper.

[Virus-induced exanthems in returning travellers]. / Virusbedingte Exantheme nach Fernreisen.

Dermatological diseases are among the most common travel-associated diseases. In particular, viral infections not only with tropical and subtropical pathogens, but also with viruses common in Germany, which are often accompanied by skin rashes and general symptoms, are of great importance. In addition to an accurate travel history and possible risk exposures, epidemiological information on country-specific risks in combination with molecular and serological analyses is helpful in making the correct diagnosis. This article provides an overview of important virus-induced exanthems in returned travellers.

Immunohistochemical markers for histopathological diagnosis and differentiation of acute cutaneous graft-versus-host disease.

Graft-versus-host disease (GvHD) is a major complication following stem-cell or solid-organ transplantation. Accurate diagnosis of cutaneous GvHD is challenging, given that drug eruptions and viral rashes may present with similar clinical/histological manifestations. Specific markers are not available. We performed the histological examination of biopsy samples from acute GvHD (aGvHD; n = 54), Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN; n = 27), maculopapular drug eruption (MDE; n = 26) and healthy controls (n = 26). Samples of aGvHD showed a decrease in Langerhans cells (LC, p = 0.0001) and an increase in macrophages (MΦ, p = 0.0001) compared to healthy skin. Compared to SJS/TEN, MDE and healthy skin, aGvHD biopsies contained greater numbers of CD4+ and CD8+ T cells. The majority of CD4+ T-helper cells were localized in the upper dermis, whereas cytotoxic CD8+ T cells were found in the epidermis. Increased numbers of CD56+ natural killer (NK) cells in the upper dermis of aGvHD skin (p = 0.007) were not observed in controls or SJS/TEN and MDE. There were no differences in elafin staining between aGvHD and the latter two conditions. Acute GvHD appears to have a distinct inflammatory cell profile (T cells/NK cells) that may aid establishing in a more accurate diagnosis, especially when used to rule out differential diagnoses such as SJS/TEN or MDE.

Dendritic cells ameliorate autoimmunity in the CNS by controlling the homeostasis of PD-1 receptor(+) regulatory T cells.

Mature dendritic cells (DCs) are established as unrivaled antigen-presenting cells (APCs) in the initiation of immune responses, whereas steady-state DCs induce peripheral T cell tolerance. Using various genetic approaches, we depleted CD11c(+) DCs in mice and induced autoimmune CNS inflammation. Unexpectedly, mice lacking DCs developed aggravated disease compared to control mice. Furthermore, when we engineered DCs to present a CNS-associated autoantigen in an induced manner, we found robust tolerance that prevented disease, which coincided with an upregulation of the PD-1 receptor on antigen-specific T cells. Additionally, we showed that PD-1 was necessary for DC-mediated induction of regulatory T cells. Our results show that a reduction of DCs interferes with tolerance, resulting in a stronger inflammatory response, and that other APC populations could compensate for the loss of immunogenic APC function in DC-depleted mice.

Pain in Hidradenitis Suppurativa: A Cross-sectional Study of 1,795 Patients.

Hidradenitis suppurativa is a chronic, inflammatory skin disorder that affects the pilosebaceous unit of the intertriginous body areas. Pain is one of the most important problems in patients with hidradenitis suppurativa. The aim of this study, which included 1,795 patients, was to evaluate the prevalence and characteristics of pain. The intensity of pain was assessed with a numerical rating scale. In addition, pain intensity was correlated with various clinical features. Pain was reported by 83.6% of subjects. The majority of patients (77.6%) experienced mild pain; women and smokers tended to experience more intense pain. Pain intensity was greater in patients with multiple affected skin areas and correlated positively with the number of those affected areas (r = 0.151, p < 0.001). There was no difference in pain intensity between affected locations. The worst pain was observed in the patients with the most severe disease and it would weaken significantly along with the severity of hidradenitis suppurativa (assessed using the Hurley staging system and the International Hidradenitis Suppurativa Severity Score System).

[Impact of LAight therapy on hidradenitis suppurativa care]. / Einfluss der LAight-Therapie auf die Versorgung der Acne inversa.

BACKGROUND: Hidradenitis suppurativa (HS) is a chronic, inflammatory skin disease with high burden for patients and limited treatment options. We recently analyzed the efficacy of local treatment with LAight therapy, a combination of intense pulsed light (IPL) and radiofrequency (RF). OBJECTIVES: The aim of the present survey was to compare care of HS patients under LAight with standard care prior to therapy. MATERIALS AND METHODS: The retrospective study included 111 patients who were treated with LAight at least 5 times between 01/2014 and 03/2017. Primary endpoint was the change in surgical interventions. Secondary endpoints included additional patient-reported outcomes, e.g., effects on their quality of life. RESULTS: In all, 50 completed surveys were available for evaluation. Under LAight therapy, the number of surgical interventions decreased from 3.2 to 0.3 per year (p < 0.001). Secondary endpoints were also significantly improved: The days of sick leave/year due to HS decreased from 30.4 to 7.2 (p = 0.002), and the number of doctor appointments due to HS flare ups was altered from 7.3 to 1.5 (p < 0.001). In line, patient-reported pain levels, general wellbeing and quality of life were also improved. CONCLUSION: This retrospective assessment of patient-reported treatment outcomes of 50 HS cases after treatment with LAight revealed a significant reduction of required surgical interventions and sick-days along with improved quality of life. Thus, it appears that IPL + RF treatment not only improves disease activity, but also secondary care aspects. Future studies will need to confirm these findings in a controlled setting.

[Parasitic dermatoses from abroad]. / Parasitäre Reisedermatosen.

Increased migration, the omnipresent desire to travel, climate change and a globally more mobile population enhance the risk of spreading infectious, tropical pathogens across international borders. In addition to diarrhea and fever, skin diseases present one of the most common reasons for a medical consultation upon return among travelers. These diseases are often caused by parasites. Detailed data on infectious travel diseases is scarce. However, demographic, endemic and travel-related information represent the basic requirements for physicians to choose appropriate diagnostics and adequate treatment for affected patients. This article gives an overview of common parasitic travel dermatoses, their specific diagnostic workup, treatment and preventive measures.

Mast cells as protectors of health.

Mast cells (MCs), which are well known for their effector functions in TH2-skewed allergic and also autoimmune inflammation, have become increasingly acknowledged for their role in protection of health. It is now clear that they are also key modulators of immune responses at interface organs, such as the skin or gut. MCs can prime tissues for adequate inflammatory responses and cooperate with dendritic cells in T-cell activation. They also regulate harmful immune responses in trauma and help to successfully orchestrate pregnancy. This review focuses on the beneficial effects of MCs on tissue homeostasis and elimination of toxins or venoms. MCs can enhance pathogen clearance in many bacterial, viral, and parasitic infections, such as through Toll-like receptor 2-triggered degranulation, secretion of antimicrobial cathelicidins, neutrophil recruitment, or provision of extracellular DNA traps. The role of MCs in tumors is more ambiguous; however, encouraging new findings show they can change the tumor microenvironment toward antitumor immunity when adequately triggered. Uterine tissue remodeling by α-chymase (mast cell protease [MCP] 5) is crucial for successful embryo implantation. MCP-4 and the tryptase MCP-6 emerge to be protective in central nervous system trauma by reducing inflammatory damage and excessive scar formation, thereby protecting axon growth. Last but not least, proteases, such as carboxypeptidase A, released by FcεRI-activated MCs detoxify an increasing number of venoms and endogenous toxins. A better understanding of the plasticity of MCs will help improve these advantageous effects and hint at ways to cut down detrimental MC actions.

COVID-19 and immunological regulations - from basic and translational aspects to clinical implications.

The COVID-19 pandemic caused by SARS-CoV-2 has far-reaching direct and indirect medical consequences. These include both the course and treatment of diseases. It is becoming increasingly clear that infections with SARS-CoV-2 can cause considerable immunological alterations, which particularly also affect pathogenetically and/or therapeutically relevant factors. Against this background we summarize here the current state of knowledge on the interaction of SARS-CoV-2/COVID-19 with mediators of the acute phase of inflammation (TNF, IL-1, IL-6), type 1 and type 17 immune responses (IL-12, IL-23, IL-17, IL-36), type 2 immune reactions (IL-4, IL-13, IL-5, IL-31, IgE), B-cell immunity, checkpoint regulators (PD-1, PD-L1, CTLA4), and orally druggable signaling pathways (JAK, PDE4, calcineurin). In addition, we discuss in this context non-specific immune modulation by glucocorticosteroids, methotrexate, antimalarial drugs, azathioprine, dapsone, mycophenolate mofetil and fumaric acid esters, as well as neutrophil granulocyte-mediated innate immune mechanisms. From these recent findings we derive possible implications for the therapeutic modulation of said immunological mechanisms in connection with SARS-CoV-2/COVID-19. Although, of course, the greatest care should be taken with patients with immunologically mediated diseases or immunomodulating therapies, it appears that many treatments can also be carried out during the COVID-19 pandemic; some even appear to alleviate COVID-19.

IL-17A/F in Leishmania major-resistant C57BL/6 mice.

Proinflammatory IL-17 plays an important role in various diseases and defence against extracellular microorganisms. Healing of leishmaniasis is promoted by Th1/Tc1 cells, whereas Th2/Treg are associated with worsened disease outcome. In addition, high expression of IL-17A in Leishmania-susceptible BALB/c and artificial overexpression of IL-17A in T cells in resistant C57BL/6 mice worsened disease outcome. Since C57BL/6 mice lacking only IL-17A exhibited no phenotype, and IL-17A and IL-17F share similar receptors, but differentially regulate chemokine secretion, we studied mice lacking both IL-17A and IL-17F (IL-17A/F-/- ) in infections with Leishmania major. Interestingly, lesion volumes and parasite burdens were comparable to controls, IL-17A/F-/- mice developed a Th1/Tc1 phenotype, and exhibited normal lesion resolution. Thus, in C57BL/6 mice, secretion of IL-17A and IL-17F does not influence disease progression. It appears that-depending on the genetic background-cytokines of the IL-17 family might be responsible for disease progression primarily in susceptible mice.

Humanized mice in cutaneous leishmaniasis-Suitability analysis of human PBMC transfer into immunodeficient mice.

Humanized mice represent a suitable preclinical test system for example therapeutic interventions in various disease settings, including infections. Here, we intended to establish such system for cutaneous leishmaniasis by infecting T, B and NK cell-deficient mice adoptively transferred with human peripheral blood mononuclear cells (PBMC). L major infection led to the establishment of parasite lesions harbouring viable parasites and human T cells, but parasite elimination was not seen due to a species-specific activity of T cell-derived human IFNγ. In addition, up to 50% of infected mice succumbed to severe graft-versus-host disease. In summary, even though long-term disease outcome assessments are impossible, this model of humanized mice can be used for studying lesion development and generation of oligoclonal anti-parasite human T cell responses in vivo.

[Exanthema after travel abroad]. / Exantheme nach Auslandsreisen.

In view of globalization and the associated transport of goods as well as rising travel activity, imported infections with subtropical and tropical pathogens are increasing in Germany. In returning travelers presenting with fever, general symptoms and skin rash, a number of diseases need to be considered. The clinical appearance of the skin rash, accurate travel history and epidemiological information on country-specific risks are helpful in making the correct diagnosis. In this article we provide an overview of the most common exanthemas in travelers who have returned, associated symptoms, diagnostic methods, therapies, as well as prevention strategies.

Cutaneous leishmaniasis: Distinct functions of dendritic cells and macrophages in the interaction of the host immune system with Leishmania major.

Leishmaniasis is transmitted by sand flies leading to parasite inoculation into skin. In the mammalian host, the parasite primarily resides in skin macrophages (MΦ) and dendritic cells (DC). MΦ are silently invaded by the parasite eliciting a stress response, whereas DC become activated, release IL-12, and prime antigen-specific T cells. Here we review the basics of the immune response against this human pathogen and elucidate the role and function DC and MΦ for establishment of protective immunity against leishmaniasis. We focus on cell type-specific differences in parasite uptake, phagocyte activation and processing of parasite antigens to facilitate an understanding how their respective function may be modulated e.g. under therapeutic considerations.