Search results for "Imiquimod"

9-Phenanthrol enhances the generation of an CD8 + T cell response following transcutaneous immunization with imiquimod in mice

2017

Abstract Background Transcutaneous immunization (TCI) is a non-invasive vaccination strategy targeting the skin-associated lymphoid tissue. Topical application of the TLR7 agonist imiquimod as adjuvant in combination with peptide antigens activates the innate immune system and mounts cytotoxic T lymphocyte (CTL) responses. Objective Based on the commercial 5% imiquimod-containing drug Aldara we aimed to develop an improved formulation with superior vaccination efficiencies. The primary target was the enhancement of mast cell activation as important key for the function of the innate immune system. Methods We investigated the effects of 9-phenanthrol (9-phe) on the activation of mast cells i…

An Alternative Pathway of Imiquimod-Induced Psoriasis-Like Skin Inflammation in the Absence of Interleukin-17 Receptor A Signaling

2013

Topical application of imiquimod (IMQ) on the skin of mice induces inflammation with common features found in psoriatic skin. Recently, it was postulated that IL-17 has an important role both in psoriasis and in the IMQ model. To further investigate the impact of IL-17RA signaling in psoriasis, we generated IL-17 receptor A (IL-17RA)-deficient mice (IL-17RA(del)) and challenged these mice with IMQ. Interestingly, the disease was only partially reduced and delayed but not abolished when compared with controls. In the absence of IL-17RA, we found persisting signs of inflammation such as neutrophil and macrophage infiltration within the skin. Surprisingly, already in the naive state, the skin …

Cutting edge: priming of CTL by transcutaneous peptide immunization with imiquimod.

2005

Abstract CTL are important in combating cancer and viruses. Therefore, triggering the complete potential of CTL effector functions by new vaccination strategies will not only improve prophylaxis of tumor or virus-related diseases, but also open opportunities for effective therapeutic immunizations. Using transcutaneous immunization, we show that epicutaneous (e.c.)4 application of an ointment containing a CTL epitope and the TLR7 ligand imiquimod is highly effective in activating T cells in mice using TCR-transgenic CTL or in wild-type mice. Transcutaneous immunization-activated CTL mount a full-blown immune response against the target epitope characterized by proliferation, cytolytic activ…

Mast cells are crucial for early inflammation, migration of Langerhans cells, and CTL responses following topical application of TLR7 ligand in mice.

2007

Abstract Until recently, IgE-activated mast cells have been regarded merely as effector cells of adaptive immune responses, involved in allergic reactions and mucosal immunity to parasites. Herein, we report that murine dermal mast cells, activated by local administration of a cream containing the synthetic TLR7 ligand imiquimod, are essential to initiate an early inflammatory reaction. The mast-cell–derived cytokines TNF-α and IL-1β play an important role in this process. Furthermore, TLR7-activated mast cells are also able to promote the emigration of Langerhans cells, which partly depends on the expression of mast-cell–derived IL-1β. We have previously shown that TLR7 ligation enhances t…

Imiquimod-Induced Psoriasis in Mice Depends on the IL-17 Signaling of Keratinocytes

2018

The pathology of psoriasis strongly depends on IL-17A. Monoclonal antibodies blocking either the cytokine or its receptor are among the most efficient treatments for psoriatic patients. Keratinocytes can be activated upon exposure to IL-17A and tumor necrosis factor-α and secrete secondary cytokines and chemokines in the inflamed skin. In psoriasis and its imiquimod-induced mouse model, a strong skin infiltration of neutrophils and inflammatory monocytes can be observed. However, to date, it is not clear how exactly those cellular populations are attracted to the skin and how they contribute to the pathogenesis of the disease. To define the crucial cell type responding to IL-17 and initiati…

Langerinneg conventional dendritic cells produce IL-23 to drive psoriatic plaque formation in mice.

2013

Psoriasis is an autoinflammatory skin disease of unknown etiology. Topical application of Aldara cream containing the Toll-like receptor (TLR)7 agonist Imiquimod (IMQ) onto patients induces flares of psoriasis. Likewise, in mice IMQ triggers pathological changes closely resembling psoriatic plaque formation. Key cytokines like IL-23 and type-I IFN (IFN-I), both being produced mainly by dendritic cells (DCs), have been implicated in psoriasis. Although plasmacytoid DCs (pDCs) are the main source of IFNα and thought to initiate disease, conventional DCs (cDCs) appear to maintain the psoriatic lesions. Any role of cDCs during lesion formation remains elusive. Here, we report that selective ac…

Of men and mice: analysing the action of an established drug using tumour necrosis factor-α-deficient mice in the imiquimod psoriasis model

2016

Physician–patient communication and patient-reported outcomes in the actinic keratosis treatment adherence initiative (AK-TRAIN): a multicenter, pros…

2017

Background: Patients with multiple actinic keratoses (AKs) should be treated with field-directed therapy. Such treatments challenge patients’ adherence due to out-of-pocket costs, length of treatment and severity of local skin reactions (LSRs). Effective physician–patient communication (PPC) may buffer therapy-related distress, thus improving quality of life, treatment satisfaction and adherence. Objectives: We evaluated the interplay between PPC, LSR intensity (safety) and lesion clearance rates (effectiveness) on treatment satisfaction, quality of life and treatment adherence among patients with multiple AKs receiving topical field-directed therapies. Methods: In this observational, multi…

Preliminary communication: imiquimod in mixed capillary/lymphatic malformation.

2008

:  The present authors reported a 14-year-old white boy who visited the present authors’ dermatology department in January 2004. Physical examination revealed multiple translucent and hemorrhagic vesicles and skin-colored nodules on the chin. The lesion had grown slowly in size over the previous 7 years. The objective of this study is to estimate the exact mechanism of action of topical imiquimod on mixed capillary/lymphatic malformation. After 4 weeks of therapy the lesions were less protuberant. At the follow-up examination after a further 2 months of therapy, there was partial clinical regression of the capillary component with a return to normal skin color. One month after termination o…

Skin Sodium Accumulates in Psoriasis and Reflects Disease Severity

2020

Sodium can accumulate in the skin at concentrations exceeding serum levels. A high sodium environment can lead to pathogenic T helper 17 cell expansion. Psoriasis is a chronic inflammatory skin disease in which IL-17. producing T helper 17 cells play a crucial role. In an observational study, we measured skin sodium content in patients with psoriasis and in age-matched healthy controls by Sodium-23 magnetic resonance imaging. Patients with PASI > 5 showed significantly higher sodium and water content in the skin but not in other tissues than those with lower PASI or healthy controls. Skin sodium concentrations measured by Sodium-23 spectroscopy or by atomic absorption spectrometry in ashed-…