Skin resident memory CD8+ T cells are phenotypically and functionally distinct from circulating populations and lack immediate cytotoxic function.

The in-depth understanding of skin resident memory CD8+ T lymphocytes (TRM ) may help to uncover strategies for their manipulation during disease. We investigated isolated TRM from healthy human skin, which expressed the residence marker CD69, and compared them to circulating CD8+ T cell populations from the same donors. There were significantly increased proportions of CD8+ CD45RA- CD27- T cells in the skin that expressed low levels of killer cell lectin-like receptor G1 (KLRG1), CD57, perforin and granzyme B. The CD8+ TRM in skin were therefore phenotypically distinct from circulating CD8+ CD45RA- CD27- T cells that expressed high levels of all these molecules. Nevertheless, the activation of CD8+ TRM with T cell receptor (TCR)/CD28 or interleukin (IL)-2 or IL-15 in vitro induced the expression of granzyme B. Blocking signalling through the inhibitory receptor programmed cell death 1 (PD)-1 further boosted granzyme B expression. A unique feature of some CD8+ TRM cells was their ability to secrete high levels of tumour necrosis factor (TNF)-α and IL-2, a cytokine combination that was not seen frequently in circulating CD8+ T cells. The cutaneous CD8+ TRM are therefore diverse, and appear to be phenotypically and functionally distinct from circulating cells. Indeed, the surface receptors used to distinguish differentiation stages of blood T cells cannot be applied to T cells in the skin. Furthermore, the function of cutaneous TRM appears to be stringently controlled by environmental signals in situ.

An immunologically relevant rodent model demonstrates safety of therapy using a tumour-specific IgE.

BACKGROUND: Designing biologically informative models for assessing the safety of novel agents, especially for cancer immunotherapy, carries substantial challenges. The choice of an in vivo system for studies on IgE antibodies represents a major impediment to their clinical translation, especially with respect to class-specific immunological functions and safety. Fcε receptor expression and structure are different in humans and mice, so that the murine system is not informative when studying human IgE biology. By contrast, FcεRI expression and cellular distribution in rats mirror that of humans. METHODS: We are developing MOv18 IgE, a human chimeric antibody recognizing the tumour-associated antigen folate receptor alpha. We created an immunologically congruent surrogate rat model likely to recapitulate human IgE-FcεR interactions and engineered a surrogate rat IgE equivalent to MOv18. Employing this model, we examined in vivo safety and efficacy of antitumour IgE antibodies. RESULTS: In immunocompetent rats, rodent IgE restricted growth of syngeneic tumours in the absence of clinical, histopathological or metabolic signs associated with obvious toxicity. No physiological or immunological evidence of a "cytokine storm" or allergic response was seen, even at 50 mg/kg weekly doses. IgE treatment was associated with elevated serum concentrations of TNFα, a mediator previously linked with IgE-mediated antitumour and antiparasitic functions, alongside evidence of substantially elevated tumoural immune cell infiltration and immunological pathway activation in tumour-bearing lungs. CONCLUSION: Our findings indicate safety of MOv18 IgE, in conjunction with efficacy and immune activation, supporting the translation of this therapeutic approach to the clinical arena.

Early intervention in psoriasis and immune-mediated inflammatory diseases: A hypothesis paper.

Psoriasis is an immune-mediated inflammatory disease (IMID) which may have a major impact on a patient's life, especially when the disease is moderate to severe. There is evidence that treatment of psoriasis during the first years is conservative and frequently based on topical agents which rarely clear lesions. Treatment with systemic agents including biologics is often undertaken only when topical agents have proved unsuitable, even in patients with moderate to severe disease. However, there is evidence that in other IMIDs (rheumatoid arthritis and Crohn's disease), targeted systemic treatment given early in the treatment pathway may improve long-term patient outcomes. We hypothesize that a patient-centered therapeutic approach, undertaken early in the psoriasis treatment pathway ("early intervention") with the goal of complete clearance, may improve control of cutaneous symptoms and may also modify disease course and burden. Critical points to address when designing an early intervention study would include: the definition of psoriasis disease activity; patient selection; intervention selection; and dosing strategies.

Clinical relevance of immunogenicity of biologics in psoriasis: implications for treatment strategies.

Biological drugs such as the tumour necrosis factor inhibitors have revolutionized the treatment of psoriasis, but some have the potential to induce an unwanted immune response. This immunogenicity may be associated with low trough drug levels, reduced clinical efficacy, reduced drug survival and an increased risk for adverse events. This article presents a literature review of the evidence on immunogenicity of biologics used in the treatment of psoriasis and considers the implications for therapeutic decision-making in the management of patients with moderate-to-severe psoriasis.

Psoriasis beyond the skin: an expert group consensus on the management of psoriatic arthritis and common co-morbidities in patients with moderate-to-severe psoriasis.

BACKGROUND: Psoriatic arthritis (PsA) and co-morbidities of psoriasis represent a significant clinical and economic burden for patients with moderate-to-severe psoriasis. Often these co-morbidities may go unrecognized or undertreated. While published data are available on the incidence and impact of some of them, practical guidance for dermatologists on detection and management of these co-morbidities is lacking. OBJECTIVE: To prepare expert recommendations to improve the detection and management of common co-morbidities in patients with moderate-to-severe psoriasis. METHODS: A systematic literature review was conducted on some common co-morbidities of psoriasis-cardiovascular (CV) diseases (including obesity, hypertension, hyperglycaemia and dyslipidaemia), psychological co-morbidities (including depression, alcohol abuse and smoking) and PsA-to establish the incidence and impact of each. Data gaps were identified and a Delphi survey was carried out to obtain consensus on the detection and management of each co-morbidity. The expert panel members for the Delphi survey comprised 10 dermatologists with substantial clinical expertise in managing moderate-to-severe psoriasis patients, as well as a cardiologist and a psychologist (see appendix) with an interest in dermatology. Agreement was defined using a Likert scale of 1-7. Consensus regarding agreement for each statement was defined as ≥75% of respondents scoring either 1 (strongly agree) or 2 (agree). RESULTS: The expert panel members addressed several topics including screening, intervention, monitoring frequency, and the effects of anti-psoriatic treatment on each co-morbidity. Consensus was achieved on 12 statements out of 22 (3 relating to PsA, 4 relating to psychological factors, 5 relating to CV factors). The panel members felt that dermatologists have an important role in screening their psoriasis patients for PsA and in assessing them for psychological and CV co-morbidities. In most cases, however, patients should be referred for specialist management if other co-morbidities are detected. CONCLUSION: This article provides useful and practical guidance for the detection and management of common co-morbidities in patients with moderate-to-severe psoriasis.

The mechanistic basis for psoriasis immunopathogenesis: translating genotype to phenotype. Report of a workshop, Venice, 2012.

The International Psoriasis Council, a global nonprofit organization dedicated to advancing psoriasis research and treatment, led an initiative to better define the pathogenic mechanisms that constitute psoriasis. In September 2012, a workshop was held at the 42nd Annual European Society for Dermatological Research in Venice, Italy. By assembling a panel of global dermatology and immunology experts, the objective was to evaluate the current status of the science explaining the mechanism of disease in psoriasis, e.g. dysregulation of the skin immune system and perturbations of epidermal homeostasis. The workshop consisted of four oral presentations, which addressed key topics in psoriasis, delivered by Hervé Bachelez (Paris, France), Antonio Costanzo (Rome, Italy), Michelle Lowes (New York, NY, U.S.A.) and Frank Nestle (London, U.K.). A global expert panel was assembled to stimulate dialogue and debate: Kevin Cooper (Cleveland, OH, U.S.A.), Michel Gilliet (Lausanne, Switzerland), Joerg Prinz (Munich, Germany), Martin Röcken (Tubingen, Germany), Jens Schroeder (Kiel, Germany), Manuelle Viguier (Paris, France), Mayte Suárez-Fariñas (New York, NY, U.S.A.) and Cristina Zielinski (Berlin, Germany). Collectively, the presentations demonstrated the significant advances in understanding immune regulation that have occurred over the past decade by virtue of the study of psoriasis subtypes, phenotypic manifestations and genetic associations. Elucidating the pathogenic and genetic basis of psoriasis holds the promise of a complete understanding of disease mechanisms, predictors of treatment response, novel drug development strategies and customized therapeutic regimens for the individual patient.

Harnessing engineered antibodies of the IgE class to combat malignancy: initial assessment of FcɛRI-mediated basophil activation by a tumour-specific IgE antibody to evaluate the risk of type I hypersensitivity.

BACKGROUND: IgE antibodies, sequestered into tissues and retained locally by the high-affinity IgE receptor, FcɛRI, on powerful effector cells such as mast cells, macrophages and eosinophils, may offer improvements in the therapy of solid tumours. The chimeric antibody, MOv18 IgE, against the human ovarian carcinoma antigen, folate receptor α (FRα), is more effective than its IgG1 counterpart in xenograft models of ovarian cancer. Although MOv18 IgE binds to a single epitope on FRα and cannot cross-link IgE receptors on basophils, there remains a risk that components in the circulation of ovarian cancer patients might cross-link FRα-MOv18-IgE-receptor-FcɛRI complexes on basophils to cause type I hypersensitivity. OBJECTIVE: To assess the propensity for MOv18 used in a therapeutic setting to cause FcɛRI-mediated type I hypersensitivity. METHODS: As validated readouts of the potential for MOv18 to cause FcɛRI-mediated type I hypersensitivity we measured release of a granule-stored mediator from a rat basophilic leukaemia cell line RBL SX-38 stably transfected with human tetrameric (αßγ2) FcɛRI, and induction of CD63 on blood basophils from patients with ovarian carcinoma and healthy controls ex vivo. RESULTS: Serum FRα levels were increased in ovarian cancer patients compared with healthy controls. MOv18 IgE alone, or in the presence of its antigen recombinant human FRα, or of healthy volunteer (n=14) or ovarian carcinoma patient (n=32) sera, did not induce RBL SX-38 cell degranulation. Exposure to FRα-expressing ovarian tumour cells at target-to-effector ratios expected within tumours induced degranulation. MOv18 IgE did not induce expression of CD63 in blood basophils from either healthy volunteers (n=6), or cancer patients, despite detectable levels of circulating FRα (n=5). CONCLUSION AND CLINICAL RELEVANCE: These encouraging data are compatible with the hypothesis that, when ovarian carcinoma patients are treated with MOv18, FcɛRI-mediated activation of effector cells occurs within the tumour mass but not in the circulation mandating, with due caution, further pre-clinical studies.

Regression of melanoma metastases following treatment with the n-bisphosphonate zoledronate and localised radiotherapy.

We report a case of regression of pulmonary and bony metastases in a patient with malignant melanoma following palliative treatment with systemic zoledronate and localised radiotherapy to the bone. Zoledronate is a potent new bisphosphonate used for the treatment of metabolic bone diseases including bone metastases due to its inhibitory effect on osteoclasts. In the context of metastatic cancer zoledronate is routinely used to improve bone pain and reduce the frequency of skeletal events. There is also an increasing body of evidence suggesting that bisphosphonates exhibit anti-tumour properties. Bisphosphonates are able to activate Vgamma9Vdelta2 gamma-delta T cells which can be key players in the immune defence against malignant cells. Furthermore bisphosphonates have direct anti-proliferative, anti-metastatic and pro-apoptotic effects on tumour cells. These actions, together with their low side effect profile, may prove to be useful therapeutic tools in the treatment of cancer even in the absence of bone metastases. On the basis of this case report we here review the current literature on present preclinical and clinical studies using bisphosphonates for the treatment of cancer.

Progress in understanding the immunopathogenesis of psoriasis.

This review emphasizes how translation from bench research to clinical knowledge and vice versa has resulted in considerable progress in understanding the immunopathogenesis of psoriasis. First, the journey in understanding the pathogenic mechanisms behind psoriasis is described. The roles of different components of the adaptive and innate immune systems involved in driving the inflammatory response are explained. Discovery of new immune pathways i.e. the IL23/Th17 axis and its subsequent impact on the development of novel biological therapies is highlighted. Identification of potential targets warranting further research for future therapeutic development are also discussed.

Interferon-alpha and viral triggers promote functional maturation of human monocyte-derived dendritic cells.

BACKGROUND: Type I interferons (IFNs) play an important role in the pathogenesis of many autoimmune disorders including psoriasis. In the presence of IFN-alpha and granulocyte/macrophage colony-stimulating factor (GM-CSF), monocytes differentiate into dendritic cells (DCs) referred to as IFN-DCs. IFN-DCs potentially mimic DC populations involved in psoriasis and express a wide range of Toll-like receptor (TLR) subtypes. OBJECTIVES: Recently, it was shown that single-stranded RNA (ssRNA) triggers TLR7 and TLR8; therefore we studied ssRNA, as a surrogate for ssRNA viruses and their impact on IFN-DCs. METHODS: We established culture conditions for IFN-DCs, generated from plastic adherent monocytes using GM-CSF plus IFN-alpha. For DC stimulation ssRNA40, a 20-mer ssRNA oligonucleotide was used. The phenotypic analysis of DC preparations was performed using flow cytometry. The production of various cytokines was analysed by enzyme-linked immunosorbent assay, and real-time quantitative polymerase chain reaction was used to quantify TLR and cytokine gene expression. The ability of IFN-DCs to stimulate allogeneic T-cell proliferation was evaluated in a mixed leucocyte reaction. RESULTS: We found that IFN-DCs express mRNA for TLR7 and TLR8 and that ssRNA stimulation significantly improves their costimulatory molecule expression, stabilizes their phenotype and enhances their capacity to stimulate naive T-cell proliferation. Unstimulated IFN-DCs did not produce bioactive interleukin (IL)-12 and produced low levels of other proinflammatory cytokines. In contrast, ssRNA stimulation led to a significant production of IL-12p70, IL-1beta, IL-6 and tumour necrosis factor alpha. IFN-DCs contained mRNA for IL-12p35, IL-12p40, IL-23p19, IL-27p28 and IL-27EBI, which was further increased by incubation with ssRNA. CONCLUSIONS: Our study sheds light on a potential role for IFN-alpha and viral infections in triggering DC populations in psoriasis. These results provide additional data for the better understanding of human autoimmune and antiviral responses and may also have implications for strategies developing cancer immunotherapy.

Improvement in quality of life with infliximab induction and maintenance therapy in patients with moderate-to-severe psoriasis: a randomized controlled trial.

BACKGROUND: Psoriasis has a well-documented, markedly negative effect on patient quality of life. OBJECTIVES: To evaluate the impact of long-term infliximab maintenance therapy on health-related quality of life (HRQoL) in patients with psoriasis. METHODS: The Dermatology Life Quality Index (DLQI) and 36-item Short Form Health Survey (SF-36) were administered as part of the pivotal double-blind, placebo-controlled efficacy and safety EXPRESS study of infliximab in chronic plaque psoriasis. In total, 378 patients with moderate-to-severe psoriasis were enrolled at 32 centres in Europe and Canada. Patients were randomized to receive either placebo or infliximab 5 mg kg(-1) induction at weeks 0, 2 and 6 followed by maintenance every 8 weeks; placebo patients crossed over at week 24 to receive the infliximab induction and maintenance regimen. RESULTS: At week 10, infliximab-treated patients had significantly greater improvement in DLQI scores (P < 0.001) and SF-36 physical and mental component summary scores (P < 0.001) than placebo-treated patients. Significant improvement (P < 0.001) was also seen in all eight SF-36 subscales, and was greatest for the "Bodily Pain" and "Social Functioning" scales. Significant improvement in HRQoL persisted with maintenance infliximab treatment at week 24 (P < 0.001), with patients achieving a Psoriasis Area and Severity Index score of 0 reporting the greatest benefit. Treatment-related HRQoL improvement remained substantial at week 50. CONCLUSIONS: Infliximab induction and maintenance regimens resulted in rapid, substantial, sustained and clinically meaningful improvement in both dermatology-specific and general quality of life indices in patients with psoriasis, with total clearance resulting in maximum improvement.

Current state and perspectives of dendritic cell vaccination in cancer immunotherapy.

Recent progress in the approach towards immunotherapy of cancer consists in molecular definition of tumor antigens, new tools for phenotypical and functional characterization of tumor-specific effector cells and clinical use of novel adjuvants for optimal stimulation of a cancer-specific immune response such as dendritic cells. In spite of these advances and immunological as well as clinical responses in selected patients, mechanisms involved in dendritic-cell-based cancer immunotherapy are still poorly understood. Therefore, a standardized study design and small pilot trials are needed to explore open scientific questions in future clinical trials. This review focuses on the different parameters of dendritic cell biology relevant to cancer immunotherapy and on innovative approaches to hopefully enhance the efficacy of dendritic cell vaccination.

Dacarbazine (DTIC) versus vaccination with autologous peptide-pulsed dendritic cells (DC) in first-line treatment of patients with metastatic melanoma: a randomized phase III trial of the DC study group of the DeCOG.

BACKGROUND: This randomized phase III trial was designed to demonstrate the superiority of autologous peptide-loaded dendritic cell (DC) vaccination over standard dacarbazine (DTIC) chemotherapy in stage IV melanoma patients. PATIENTS AND METHODS: DTIC 850 mg/m2 intravenously was applied in 4-week intervals. DC vaccines loaded with MHC class I and II-restricted peptides were applied subcutaneously at 2-week intervals for the first five vaccinations and every 4 weeks thereafter. The primary study end point was objective response (OR); secondary end points were toxicity, overall (OS) and progression-free survival (PFS). RESULTS: At the time of the first interim analysis 55 patients had been enrolled into the DTIC and 53 into the DC-arm (ITT). OR was low (DTIC: 5.5%, DC: 3.8%), but not significantly different in the two arms. The Data Safety & Monitoring Board recommended closure of the study. Unscheduled subset analyses revealed that patients with normal serum LDH and/or stage M1a/b survived longer in both arms than those with elevated serum LDH and/or stage M1c. Only in the DC-arm did those patients with (i) an initial unimpaired general health status (Karnofsky = 100) or (ii) an HLA-A2+/HLA-B44- haplotype survive significantly longer than patients with a Karnofsky index <100 (P = 0.007 versus P = 0.057 in the DTIC-arm) or other HLA haplotypes (P = 0.04 versus P = 0.57 in DTIC-treated patients). CONCLUSIONS: DC vaccination could not be demonstrated to be more effective than DTIC chemotherapy in stage IV melanoma patients. The observed association of overall performance status and HLA haplotype with overall survival for patients treated by DC vaccination should be tested in future trials employing DC vaccines.

Activation of dendritic antigen-presenting cells expressing common heat shock protein receptor CD91 during induction of psoriasis.

BACKGROUND: Psoriasis is a common and chronic relapsing inflammatory skin disorder. Although a role for T cells in mediating the induction and maintenance of psoriatic lesions is well established, mechanisms responsible for activation of T cells by antigen-presenting cells (APCs) during disease relapse are poorly understood. OBJECTIVES: (i) To determine whether expression of the common heat shock protein (HSP) receptor CD91 correlated with development of psoriasis in a mouse model of psoriasis, (ii) to characterize the lesional cells on which CD91 was expressed, and (iii) to investigate whether CD91+ cells in psoriasis showed signs of activation. METHODS: Two systems were used in order to study the above-mentioned objectives: (i) skin biopsies taken directly from patients with psoriasis (either psoriatic plaques or symptomless prepsoriatic skin) or from healthy donors, respectively, or (ii) (human) skin biopsies collected during development of psoriasis using a novel xenograft mouse model of psoriasis. The skin samples were then either processed for analysis by light microscopy, or labelled with fluorochrome-conjugated antibodies and analysed by confocal laser scanning microscopy. RESULTS: We observed a markedly increased number of CD91+ cells which paralleled development of new psoriatic lesions in the psoriasis mouse model and in established psoriatic plaques compared with symptomless prepsoriatic or healthy skin. Morphology as well as cell-specific markers showed that CD91 was predominantly expressed by dermal dendritic APCs characterized by activation of nuclear factor-kappaB signalling and the presence of tumour necrosis factor-alpha, an important proinflammatory cytokine in the immunopathogenesis of psoriasis. In addition, HSP70, a ligand for CD91, was increased in keratinocytes in close vicinity to CD91-bearing APCs in psoriatic lesions. CONCLUSIONS: These findings indicate massive presence of CD91+ dendritic cells juxtaposed to lesional keratinocytes expressing HSP70, and suggest a novel pathophysiological pathway and therapeutic target for this chronic inflammatory skin disease.

Successful treatment of three cases of nephrogenic fibrosing dermopathy with extracorporeal photopheresis.

BACKGROUND: Nephrogenic fibrosing dermopathy (NFD) is a recently described cutaneous fibrosing disorder associated with renal dysfunction. Patients present with thickened skin or oedematous skin with indurated papules and plaques involving extremities and trunk, and often associated with disabling contracture of the adjacent joints. The aetiology and pathogenesis remain largely unknown. As a consequence, therapeutic measures with proven efficacy are nonexistent to date. OBJECTIVES: To consider treatment with extracorporal photopheresis (ECP) in three patients. Patients We report three new cases of NFD with the characteristic clinical and pathological features. Two patients required haemodialysis due to end-stage renal failure, despite prior renal transplantation. One patient had renal dysfunction but was never on dialysis, nor had she been transplanted. ECP treatment was administered at intervals of 2-4 weeks. RESULTS: All three patients showed a softening of the skin lesions and a marked improvement of the joint motility starting after four cycles of ECP. One patient developed a complete regression of her skin lesions after 16 cycles of ECP, and response to therapy was observed despite constantly elevated renal values. CONCLUSION: These data indicate that ECP may represent a valuable therapeutic option for NFD.

The alphavbeta5 integrin of hematopoietic and nonhematopoietic cells is a transduction receptor of RGD-4C fiber-modified adenoviruses.

Epithelial and endothelial cells expressing the primary Coxsackie virus B adenovirus (Ad) receptor (CAR) and integrin coreceptors are natural targets of human Ad infections. The fiber knob of species A, C, D, E and F Ad serotypes binds CAR by mimicking the CAR-homodimer interface, and the penton base containing arginine-glycine-aspartate (RGD) motifs binds with low affinity to alphav integrins inducing cell activation. Here, we generated seven different genetically modified Ad vectors with RGD sequences inserted into the HI loop of fiber knob. All mutants bound and infected CAR and alphav integrin-positive epithelial cells with equal efficiencies. However, the Ads containing two additional cysteines, both N and C terminals of the RGD sequence (RGD-4C), were uniquely capable of transducing CAR-less hematopoietic and nonhematopoietic human tumor cell lines and primary melanoma cells. Both binding and transduction of RGD-4C Ad were blocked by soluble RGD peptides. Flow cytometry of cell surface integrins and virus binding to CAR-less cells in the presence of function-blocking anti-integrin antibodies indicated that the alphavbeta5 integrin, but not alphavbeta3, alphaIIbbeta3 or beta1,alpha5 or alpha6-containing integrins served as a functional transduction receptor of the RGD-4C Ads. However, in cells with low levels of alphavbeta5 integrin, the function-blocking anti-alphavbeta5 antibodies were not effective, unlike soluble RGD peptides. Collectively, our data demonstrate that the alphavbeta5 integrin is a functional transduction receptor of RGD-4C Ads in the absence of CAR, and that additional RGD receptors are targets of these viruses. The RGD-4C vectors further extend the tropism of Ads towards potential human therapies.

Treatment of verrucous carcinoma with imiquimod and CO2 laser ablation.

An 82-year-old female patient presented with a large perianal hyperkeratotic tumor extending into the anal canal. Staging did not reveal any metastatic spread. Diagnosis of verrucous carcinoma or Buschke-Löwenstein tumor, respectively, was based on typical clinical and histologic features. Moreover, human papillomavirus 6b DNA sequences could be detected by PCR. Surgical excision could not be performed due to the general health status of the patient; thus, alternative therapy methods were necessary. Treatment with imiquimod cream 5% (Aldara), a topical immune response modifier applied once a day and left for 12 h, led to significant partial tumor regression and clear demarcation of the tumor. The remaining tumor, now feasible for treatment with CO2 laser, was removed in two sessions in local anesthesia. In a third session, tumor parts in the anal canal were vaporized. This case demonstrates that the combination of imiquimod and CO2 laser ablation is an effective treatment option for verrucous carcinoma.

Vaccines and melanoma.

Melanoma is one of the prototypic immunogenic tumors. Various immunotherapeutic approaches for melanoma have been developed in the past decades. Recent scientific progress includes the discovery of defined melanoma antigens, new tools for monitoring of an anti-cancer immune response and application of novel adjuvants for amplification of the immune response such as dendritic cells. These and other advances in the field of melanoma vaccines will be discussed.