Nanoparticle-Coupled Topical Methotrexate Can Normalize Immune Responses and Induce Tissue Remodeling in Psoriasis

A Comparative Study of the Effectiveness and Safety of Topical Calcipotriol and Topical Methotrexate in Chronic Plaque Psoriasis

Background Psoriasis is a papulosquamous disease with variable morphology, distribution, severity, and course. Chronic plaque psoriasis, or psoriasis vulgaris, is the most common form of psoriasis. Present available preparations for mild to moderate chronic plaque psoriasis for topical use are local corticosteroids, coal tar, dithranol, tazarotene, calcipotriol, tapinarof, and calcineurin inhibitors. However, every preparation has its disadvantages. Calcipotriol, an active form of vitamin D, is available in topical form for dermatological use. Chronic plaque psoriasis is the chief medical use of calcipotriol for mild to moderate form. Methotrexate has dramatic results in psoriasis when used systemically. Now, topical formulation is being advocated in localized psoriasis, which is not associated with the side effects of the systemic form. Therefore, this study aimed to compare the effectiveness of topical calcipotriol and topical methotrexate on the basis of the psoriasis area severity index (PASI) in patients of chronic plaque psoriasis and compare their safety in terms of adverse effects. Methodology The total number of patients included in the study was 60. They were divided into two groups, with 30 patients each. One group was prescribed ointment calcipotriol 0.005% twice daily local application (Group C). The other group was prescribed methotrexate gel 1% twice daily local application (Group M). The patients were followed up on the fourth and eighth weeks, and at each time, thorough clinical examinations were conducted for all patients. The PASI score was calculated in each patient every time. Safety was assessed by biochemical parameters, and tolerability was assessed by the incidence of adverse effects. All the patients included in the study were investigated at baseline, fourth week, and eighth week. The data collected were transferred to a master chart and analyzed. Results For the patients in group C, the mean PASI score at 0 week was 5.93 ± 2.62, while at four weeks, the mean PASI score declined to 1.67 ± 1.13, and at eight weeks, the mean PASI score further declined to 0.67 ± 0.68. For the patients in group M, the mean PASI score at 0 week was 5.91 ± 2.22, while at four weeks, the mean PASI score declined to 1.91 ± 1.11, and at eight weeks, the mean PASI score further declined to 0.89 ± 0.72. Furthermore, there was no significant difference in the mean PASI score at various time points when compared between the two groups (p-value = 0.761, 0.296, 0.079, respectively). Thus, both drugs seem to be effective in treating mild- to moderate-grade chronic plaque psoriasis. Most of the patients in both groups showed marked clearance of the lesions. However, there were six patients in the calcipotriol group showing complete clearance of the lesions having mild-degree plaque psoriasis, as compared to three patients in the methotrexate group. In the present study, based on the comparison of safety and tolerability, four out of 30 patients (13.3%) in the calcipotriol group suffered skin irritation, whereas six out of 30 patients (20%) in the methotrexate group complained of a burning sensation. The adverse effects seen in the patients were transient and mild. Conclusion Topical calcipotriol and methotrexate were effective in reducing lesions in patients with chronic mild to moderate plaque psoriasis. Both drugs were well tolerated with mild and transient adverse effects and did not alter hematological and biochemical parameters.

Recent Approaches for the Topical Treatment of Psoriasis Using Nanoparticles

Psoriasis (PSO) is a chronic autoimmune skin condition characterized by the rapid and excessive growth of skin cells, which leads to the formation of thick, red, and scaly patches on the surface of the skin. These patches can be itchy and painful, and they may cause discomfort for patients affected by this condition. Therapies for psoriasis aim to alleviate symptoms, reduce inflammation, and slow down the excessive skin cell growth. Conventional topical treatment options are non-specific, have low efficacy and are associated with adverse effects, which is why researchers are investigating different delivery mechanisms. A novel approach to drug delivery using nanoparticles (NPs) shows promise in reducing toxicity and improving therapeutic efficacy. The unique properties of NPs, such as their small size and large surface area, make them attractive for targeted drug delivery, enhanced drug stability, and controlled release. In the context of PSO, NPs can be designed to deliver active ingredients with anti-inflammatory effect, immunosuppressants, or other therapeutic compounds directly to affected skin areas. These novel formulations offer improved access to the epidermis and facilitate better absorption, thus enhancing the therapeutic efficacy of conventional anti-psoriatic drugs. NPs increase the surface-to-volume ratio, resulting in enhanced penetration through the skin, including intracellular, intercellular, and trans-appendage routes. The present review aims to discuss the latest approaches for the topical therapy of PSO using NPs. It is intended to summarize the results of the in vitro and in vivo examinations carried out in the last few years regarding the effectiveness and safety of nanoparticles.

Engineered Nanomaterials for Immunomodulation: A Review

The immune system usually provides a defense against invading pathogenic microorganisms and any other particulate contaminants. Nonetheless, it has been recently reported that nanomaterials can evade the immune system and modulate immunological responses due to their unique physicochemical characteristics. Consequently, nanomaterial-based activation of immune components, i.e., neutrophils, macrophages, and other effector cells, may induce inflammation and alter the immune response. Here, it is essential to distinguish the acute and chronic modulations triggered by nanomaterials to determine the possible risks to human health. Nanomaterials size, shape, composition, surface charge, and deformability are factors controlling their uptake by immune cells and the resulting immune responses. The exterior corona of molecules adsorbed over nanomaterials surfaces also influences their immunological effects. Here, we review current nanoengineering trends for targeted immunomodulation with an emphasis on the design, safety, and potential toxicity of nanomaterials. First, we describe the characteristics of engineered nanomaterials that trigger immune responses. Then, the biocompatibility and immunotoxicity of nanoengineered particles are debated, because these factors influence applications. Finally, future nanomaterial developments in terms of surface modifications, synergistic approaches, and biomimetics are discussed.

Potential strategy of microneedle-based transdermal drug delivery system for effective management of skin-related immune disorders

Skin-related immune disorders are a category of diseases that lead to the dysregulation of the body's immune response due to imbalanced immune regulation. These disorders exhibit diverse clinical manifestations and complicated pathogenesis. The long-term use of corticosteroids, anti-inflammatory drugs, and immunosuppressants as traditional treatment methods for skin-related immune disorders frequently leads to adverse reactions in patients. In addition, the effect of external preparations is not ideal in some cases due to the compacted barrier function of the stratum corneum (SC). Microneedles (MNs) are novel transdermal drug delivery systems that have theapparent advantages ofpenetrating the skin barrier, such as long-term and controlled drug delivery, less systemic exposure, and painless and minimally invasive targeted delivery. These advantages make it a good candidate formulation for the treatment of skin-related immune disorders and a hotspot for research in this field. This paper updates the classification, preparation, evaluation strategies, materials, and related applications of five types of MNs. Specific information, including the mechanical properties, dimensions, stability, and in vitro and in vivo evaluations of MNs in the treatment of skin-related immune disorders, is also discussed. This review provides an overview of the advances and applications of MNs in the effective treatment of skin-related immune disorders and their emerging trends.

Doxorubicin and folic acid-loaded zinc oxide nanoparticles-based combined anti-tumor and anti-inflammatory approach for enhanced anti-cancer therapy

BACKGROUND

Zinc oxide nanoparticles (ZnONPs) have impressively shown their efficacy in targeting and therapy of cancer. The present research was designated to investigate the potential of ZnONP nanocomposites as a cancer chemotherapeutic-based drug delivery system and to assess the anti-tumor and anti-inflammatory effectiveness of ZnONP nanocomposites combination with systemic chemotherapeutic drugs doxorubicin (DOX) and folic acid (FA) in Ehrlich ascites carcinoma (EAC) tumor cell line both in vitro and in vivo.

METHODS

Anti-tumor potential of ZnONP nanocomposites: ZnONPs, ZnONPs/FA, ZnONPs/DOX and ZnONPs/DOX/FA against EAC tumor cell line was evaluated in vitro by MTT assay. Anti-tumor and anti-inflammatory efficacy of ZnONP nanocomposites were analyzed in vivo by examination of the proliferation rate and apoptosis rate of EAC tumor cells by flow cytometry, splenocytes count, level of inflammatory markers interleukin 6 (IL-6) and tumor necrosis factor alpha (TNF-α), as well as liver and kidney function in EAC-challenged mice.

RESULTS

In vitro results showed that ZnONP nanocomposites showed a high anti-proliferative potency against EAC tumor cells. Furthermore, the in vivo study revealed that the treatment EAC-challenged mice with ZnONPs, ZnONPs/DOX, ZnONPs/FA and ZnONPs/DOX/FA hindered the proliferation rate of implanted EAC tumor cells through lowering their number and increasing their apoptosis rate. Moreover, the treatment of EAC-challenged mice with ZnONPs/DOX/FA markedly decreased the level of IL-6 and TNF-α and remarkably ameliorated the liver and kidney damages that were elevated by implantation of EAC tumor cells, restoring the liver and kidney functions to be close to the naïve mice control.

CONCLUSION

ZnONP nanocomposites may be useful as a cancer chemotherapeutic-based drug delivery system. ZnONP nanocomposites: ZnONPs/DOX, ZnONPs/FA and ZnONPs/DOX/FA regimen may have anti-inflammatory approaches and a great potential to increase anti-tumor effect of conventional chemotherapy, overcoming resistance to cancer systemic chemotherapeutics and reducing their side effects, offering a promising regimen for cancer therapy.

Nanomedicine-mediated drug delivery for potential treatment of inflammatory bowel disease: a narrative review

Background & aims: Inflammatory bowel disease (IBD) is a condition characterized by chronic inflammation of the gastrointestinal tract, manifesting as either Crohn's disease (CrD) or ulcerative colitis (UC). Current treatment options for CrD and UC primarily focus on symptom management. In recent years, advancements in nanotechnology have increased the clinical applicability of nanoparticles (NPs) in treating IBD. This review explores the current research on NP-mediated drug-delivery systems for IBD treatment and assesses its advantages and limitations. Results: The authors examine diverse nanomedicine applications for IBD and address the current challenges and prospects in the field to advance nanomediated therapies in the future. Conclusion: Innovative NP-based treatment strategies promise a reliable and effective approach to IBD management.

Challenges and Future Trends in the Treatment of Psoriasis

Psoriasis is a chronic inflammatory skin disorder, and current treatments include topical therapies, phototherapy, systemic immune modulators, and biologics, aiming to alleviate symptoms and improve quality of life. However, challenges persist, such as adverse effects, treatment resistance, high costs, and variability in response among individuals. The future of psoriasis treatment shows promising emerging trends. New biologic agents targeting novel pathways, such as interleukin 23 inhibitors like mirikizumab, offer enhanced efficacy. Small molecule inhibitors like RORγt inhibitors and ROCK2 inhibitors provide additional treatment options. Combination therapies, including biologics with methotrexate, may improve treatment response. Advancements in topical treatments utilizing microneedles and nanoparticle-based carriers can enhance drug delivery and improve therapeutic outcomes. Biomarkers and multi-omics technologies hold potential for personalized treatment approaches, thus aiding in diagnosis, predicting treatment response, and guiding therapeutic decisions. Collaboration among researchers, clinicians, and industry stakeholders is crucial to translating these scientific breakthroughs into clinical practice. By addressing current challenges and exploring these promising trends, we can optimize psoriasis management and improve the lives of those affected by this chronic condition.

Advances in pathogenesis and nanoparticles (NPs)-mediated treatment of psoriasis

Psoriasis is a chronic papulosquamous skin disease with an autoimmune pathogenic traits and strong genetic predisposition. In the past few decades, with the rapid development of molecular biology and cell biology, the inherent pathogenesis of psoriasis has been gradually elucidated, in which cytokine inflammatory loops, cell signaling pathways, and epigenetic factors such as miRNAs have been demonstrated to play important roles in regulating the development and progression of psoriasis. More importantly, understanding the pathogenesis of psoriasis has promoted the development of effective treatment for psoriasis. In this review, we systemically summarized the molecular mechanisms regulating the development and progression psoriasis, introduced various therapeutics used for clinical psoriasis therapy, and highlighted the recent advances in nanoparticles (NPs)-mediated drug delivery for psoriasis treatment.

Mechanisms regulating neutrophil responses in immunity, allergy, and autoimmunity

Neutrophil granulocytes, or neutrophils, are the most abundant circulating leukocytes in humans and indispensable for antimicrobial immunity, as exemplified in patients with inborn and acquired defects of neutrophils. Neutrophils were long regarded as the foot soldiers of the immune system, solely destined to execute a set of effector functions against invading pathogens before undergoing apoptosis, the latter of which was ascribed to their short life span. This simplistic understanding of neutrophils has now been revised on the basis of insights gained from the use of mouse models and single-cell high-throughput techniques, revealing tissue- and context-specific roles of neutrophils in guiding immune responses. These studies also demonstrated that neutrophil responses were controlled by sophisticated feedback mechanisms, including directed chemotaxis of neutrophils to tissue-draining lymph nodes resulting in modulation of antimicrobial immunity and inflammation. Moreover, findings in mice and humans showed that neutrophil responses adapted to different deterministic cytokine signals, which controlled their migration and effector function as well as, notably, their biologic clock by affecting the kinetics of their aging. These mechanistic insights have important implications for health and disease in humans, particularly, in allergic diseases, such as atopic dermatitis and allergic asthma bronchiale, as well as in autoinflammatory and autoimmune diseases. Hence, our improved understanding of neutrophils sheds light on novel therapeutic avenues, focusing on molecularly defined biologic agents.

The Anti-Psoriatic Efficacy and Safety Profile of Topical and Intralesional Methotrexate: A Literature Review

Methotrexate (MTX) has long been considered the first-line oral systemic pharmacotherapy for psoriasis. The drug has several well-known systemic side effects, such as bone marrow suppression and hepatotoxicity. To avoid them, the use of topical or intralesional administrations of MTX has become an interesting option. With the advent of novel drug delivery systems, especially nanocarriers, the usage of a high-efficacy and safe topical MTX for psoriasis has nearly been attained. This review examined the development, anti-psoriatic efficacy and adverse effects of topical forms of MTX (plain MTX; MTX with chemical enhancer; MTX using nanotechnology; MTX with protein transduction domains; MTX with liquid crystalline systems; and MTX with physical enhancer/laser) and intralesional MTX in psoriasis patients and psoriasis-induced animals. The efficacy of topical MTX varied with the drug delivery technology employed. Nevertheless, the overall safety profile of the topical forms was favourable. A 25 mg/mL MTX solution injected intralesionally at the nail matrix worked well for nail psoriasis recalcitrant to topical treatment. To improve the standard of care for patients with psoriasis, randomized controlled trials that establish the most effective MTX-delivery system are needed.

Advances in the modulation of ROS and transdermal administration for anti-psoriatic nanotherapies

Reactive oxygen species (ROS) at supraphysiological concentration have a determinate role in contributing to immuno-metabolic disorders in the epithelial immune microenvironment (EIME) of psoriatic lesions. With an exclusive focus on the gene-oxidative stress environment interaction in the EIME, a comprehensive strategy based on ROS-regulating nanomedicines is greatly anticipated to become the mainstay of anti-psoriasis treatment. This potential therapeutic modality could inhibit the acceleration of psoriasis via remodeling the redox equilibrium and reshaping the EIME. Herein, we present a marked overview of the current progress in the pathomechanisms of psoriasis, with particular concerns on the potential pathogenic role of ROS, which significantly dysregulates redox metabolism of keratinocytes (KCs) and skin-resident or -infiltrating cells. Meanwhile, the emergence of versatile nanomaterial-guided evolution for transdermal drug delivery has been attractive for the percutaneous administration of antipsoriatic therapies in recent years. We emphasize the underlying molecular mechanism of ROS-based nanoreactors for improved therapeutic outcomes against psoriasis and summarize up-to-date progress relating to the advantages and limitations of nanotherapeutic application for transdermal administration, as well as update an insight into potential future directions for nanotherapies in ROS-related skin diseases.

Gold nanoparticles for skin drug delivery

Nanoparticle-based drug carriers are being pursued intensely to overcome the skin barrier and improve even hydrophilic or macromolecular drug delivery into or across the skin efficiently. Over the past few years, the application of gold nanoparticles as a novel kind of drug carrier for skin drug delivery has attracted increasing attention because of their unique properties and versatility. In this review, we summarized the possible factors contributing to the penetration behaviors of gold nanoparticles, including size, surface chemistry, and shape. Drug loading, release, and penetration patterns were captured towards implicating the design of gold nanoparticles for dermal or transdermal drug delivery. Physical methods applicable for future enhancing the delivery efficacy of GNPs were also presented, which mainly included microneedles and iontophoresis. As a promising "drug", the inherent activities of GNPs were finally discussed, especially regarding their application in the treatment of skin disease. Thus, this paper provided a comprehensive review of the use of gold nanoparticles for skin drug delivery, which would help the design of multifunctional systems for skin drug delivery based on gold nanoparticles.

Latest on biomaterial-based therapies for topical treatment of psoriasis

Psoriasis is an autoimmune inflammatory disease which is fundamentally different from dermatitis. Its treatments include topical medications and systemic drugs depending on different stages of the disease. However, these commonly used therapies are falling far short of clinical needs due to various drawbacks. More precise therapeutic strategies with minimized side effects and improved compliance are highly demanded. Recently, the rapid development of biomaterial-based therapies has made it possible and promising to attain topical psoriasis treatment. In this review, we briefly describe the significance and challenges of the topical treatment of psoriasis and emphatically overview the latest progress in novel biomaterial-based topical therapies for psoriasis including microneedles, nanoparticles, nanofibers, and hydrogels. Current clinical trials related to each biomaterial are also summarized and discussed.

Type 2 immune predisposition results in accelerated neutrophil aging causing susceptibility to bacterial infection

Atopic individuals show enhanced type 2 immune cell responses and a susceptibility to infections with certain bacteria and viruses. Although patients with allergic diseases harbor normal counts of circulating neutrophils, these cells exert deficient effector functions. However, the underlying mechanism of this dysregulation of neutrophils remains ill defined. Here, we find that development, aging, and elimination of neutrophils are accelerated in mice with a predisposition to type 2 immunity, which, in turn, causes susceptibility to infection with several bacteria. Neutrophil-mediated immunity to bacterial infection was greatly decreased in mice with a genetic or induced bias to type 2 immunity. Abrogation of interleukin-4 (IL-4) receptor signaling in these animals fully restored their antibacterial defense, which largely depended on Ly6G⁺ neutrophils. IL-4 signals accelerated the maturation of neutrophils in the bone marrow and caused their rapid release to the circulation and periphery. IL-4-stimulated neutrophils aged more rapidly in the periphery, as evidenced by their phenotypic and functional changes, including their decreased phagocytosis of bacterial particles. Moreover, neutrophils from type 2 immune predisposed mice were eliminated at a higher rate by apoptosis and phagocytosis by macrophages and dendritic cells. Collectively, IL-4 signaling-mediated neutrophil aging constitutes an important adaptive deficiency in type 2 inflammation, contributing to recurrent bacterial infections.

A multifunctional composite hydrogel as an intrinsic and extrinsic coregulator for enhanced therapeutic efficacy for psoriasis

Background

Psoriasis is a chronic relapsing immunological skin disease characterized by multiple cross-talk inflammatory circuits which are relevantly associated with abnormal cross-reactivity between immune cells and keratinocytes (KCs). It may be inadequate to eradicate complicated pathogenesis only via single-mode therapy. To provide optimal combinatory therapeutics, a nanocomposite-based hydrogel was constructed by loading methotrexate (MTX) into ZnO/Ag to realize combined multiple target therapy of psoriasis.

Results

In this composite hydrogel, ZnO hybrid mesoporous microspheres were utilized both as drug carriers and reactive oxygen species (ROS)-scavenging nanoparticles. A proper amount of Ag nanoparticle-anchored ZnO nanoparticles (ZnO/Ag) was functionalized with inherent immunoregulatory property. The experiments showed that ZnO/Ag nanoparticles could exhibit a self-therapeutic effect that was attributed to reducing innate cytokine profiles by inactivating p65 in proinflammatory macrophages and abrogating secretion of adaptive cytokines in KCs by downregulating ROS-mediated STAT3-cyclin D1 signaling. A preferable antipsoriatic efficacy was achieved via topical administration of this hydrogel on the imiquimod (IMQ)-induced psoriasis mice model, demonstrating the superior transdermal delivery and combined enhancement of therapeutic efficacy caused by intrinsic nanoparticles and extrinsic MTX.

Conclusion

This composite hydrogel could serve as a multifunctional, nonirritating, noninvasive and effective transcutaneous nanoagent against psoriasis.

Graphical Abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s12951-022-01368-y.

The interaction between nanoparticles and immune system: application in the treatment of inflammatory diseases

Nanoparticle (NP) is an emerging tool applied in the biomedical field. With combination of different materials and adjustment of their physical and chemical properties, nanoparticles can have diverse effects on the organism and may change the treating paradigm of multiple diseases in the future. More and more results show that nanoparticles can function as immunomodulators and some formulas have been approved for the treatment of inflammation-related diseases. However, our current understanding of the mechanisms that nanoparticles can influence immune responses is still limited, and systemic clinical trials are necessary for the evaluation of their security and long-term effects. This review provides an overview of the recent advances in nanoparticles that can interact with different cellular and molecular components of the immune system and their application in the management of inflammatory diseases, which are caused by abnormal immune reactions. This article focuses on the mechanisms of interaction between nanoparticles and the immune system and tries to provide a reference for the future design of nanotechnology for the treatment of inflammatory diseases.

CCR7-guided neutrophil redirection to skin-draining lymph nodes regulates cutaneous inflammation and infection

Neutrophils are the first nonresident effector immune cells that migrate to a site of infection or inflammation; however, improper control of neutrophil responses can cause considerable tissue damage. Here, we found that neutrophil responses in inflamed or infected skin were regulated by CCR7-dependent migration and phagocytosis of neutrophils in draining lymph nodes (dLNs). In mouse models of Toll-like receptor-induced skin inflammation and cutaneous Staphylococcus aureus infection, neutrophils migrated from the skin to the dLNs via lymphatic vessels in a CCR7-mediated manner. In the dLNs, these neutrophils were phagocytosed by lymph node-resident type 1 and type 2 conventional dendritic cells. CCR7 up-regulation on neutrophils was a conserved mechanism across different tissues and was induced by a broad range of microbial stimuli. In the context of cutaneous immune responses, disruption of CCR7 interactions by selective CCR7 deficiency of neutrophils resulted in increased antistaphylococcal immunity and aggravated skin inflammation. Thus, neutrophil homing to and clearance in skin-dLNs affects cutaneous immunity versus pathology.

Chitosan/hyaluronan nanogels co-delivering methotrexate and 5-aminolevulinic acid: A combined chemo-photodynamic therapy for psoriasis

Psoriasis does not respond adequately to the monotherapy, tailoring combined strategies for synergistical treatment remains challenging. We fabricated chitosan/hyaluronan nanogels to co-load methotrexate (MTX) and 5-aminoleavulinic acid (ALA), i.e., MTX-ALA NGs, for a combined chemo-photodynamic therapy for psoriasis. Compared with MTX-ALA suspension, the NGs enhanced the penetration and retention of MTX and ALA through and into the skin in vitro and in vivo (p < 0.001). NGs enhanced the cellular uptake (p < 0.001), protoporphyrin IX conversion (p < 0.001), and reactive oxygen species generation (3.93-fold), subsequently exerted the synergistical anti-proliferation and apoptosis on lipopolysaccharide-irritated HaCaT cells with the apoptosis rate of 78.6%. MTX-ALA NGs efficiently ameliorated the skin manifestations and down-regulated the proinflammatory cytokines of TNF-α and IL-17A in imiquimod-induced psoriatic mice (p < 0.001). Importantly, MTX-ALA NGs reduced the toxicities of oral MTX to the liver and kidney. The results support that MTX-ALA NG is a convenient, effective, and safe combined chemo-photodynamic strategy for psoriasis treatment.

Alkyl-Terminated Gold Nanoparticles as a Self-Therapeutic Treatment for Psoriasis

We present a self-therapeutic nanoparticle for topical delivery to epidermal keratinocytes to prevent and treat psoriasis. Devoid of known chemical or biological antipsoriatic drugs, this sub-15 nm nanoparticle contains a 3 nm gold core and a shell of 1000 Da polyethylene glycol strands modified with 30% octadecyl chains. When it is applied to imiquimod-induced psoriasis mice without an excipient, the nanoparticle can cross the stratum corneum and preferentially enter keratinocytes. Applying the nanoparticles concurrently with imiquimod prevents psoriasis and downregulates genes that are enriched in the downstream of the interleukin-17 signaling pathway and linked to epidermis hyperproliferation and inflammation. Applying the nanoparticles after psoriasis is established treats the psoriatic skin as effectively as standard steroid and vitamin D analog-based therapy but without hair loss and skin wrinkling. The nanoparticles do not accumulate in major organs or induce long-term toxicity. Our nanoparticle offers a simple, safe, and effective alternative for treating psoriasis.

Green synthesis of gold nanoparticles for immune response regulation: Mechanisms, applications, and perspectives

Immune responses are involved in the pathogenesis of many diseases, including cancer, autoimmune diseases, and chronic inflammation. These responses are attributed to immune cells that produce cytokines, mediate cytotoxicity, and synthesize antibodies. Gold nanoparticles (GNPs) are novel agents that intervene with immune responses because of their unique physical-chemical properties. In particular, GNPs enhance anti-tumour activity during immunotherapy and eliminate excessive inflammation in autoimmune diseases. However, GNPs synthesized by conventional methods are toxic to living organisms. Green biosynthesis provides a safe and eco-friendly method to obtain GNPs from microbes or plant extracts. In this review, we describe several patterns for green GNP biosynthesis. The applications of GNPs to target immune cells and modulate the immune response are summarized. In particular, we elaborate on how GNPs regulate innate immunity and adaptive immunity, including inflammatory signaling and immune cell differentiation. Finally, perspectives and challenges in utilizing green biosynthesized GNPs for novel therapeutic approaches are discussed.

Strategies to Develop a Suitable Formulation for Inflammatory Skin Disease Treatment

Skin barrier functions, environmental insults, and genetic backgrounds are intricately linked and form the basis of common inflammatory skin disorders, such as atopic dermatitis, psoriasis, and seborrheic dermatitis, which may seriously affect one’s quality of life. Topical therapy is usually the first line of management. It is believed that successful topical treatment requires pharmaceutical formulation from a sufficient dosage to exert therapeutic effects by penetrating the stratum corneum and then diffusing to the target area. However, many factors can affect this process including the physicochemical properties of the active compound, the composition of the formulation base, and the limitations and conditions of the skin barrier, especially in inflammatory skin. This article briefly reviews the available data on these issues and provides opinions on strategies to develop a suitable formulation for inflammatory skin disease treatment.

Dihydroartemisinin ameliorates psoriatic skin inflammation and its relapse by diminishing CD8+ T-cell memory in wild-type and humanized mice

Conventional immunosuppressants cause side effects and do not prevent the recurrence of autoimmune diseases. Moreover, they may not inhibit autoimmunity mediated by pathogenic memory T-cells. Dihydroartemisinin (DHA) has been shown to regulate autoimmunity. However, it remains unknown whether DHA impacts psoriasis and its recurrence. The objective of this study was to determine therapeutic effects of DHA on psoriasis and its relapse as well as its underlying mechanisms.

Methods: We established animal models of imiquimod (IMQ)-induced psoriasis-like wild-type mice and humanized NSG mice receiving lesional human skin from patients with psoriasis. Many immunoassays, including immunohistochemistry, flow cytometry, quantitative RT-PCR and Western blotting, were performed.

Results: We found that DHA not only ameliorated acute skin lesion of psoriatic mice, but also alleviated its recurrence by diminishing CD8⁺ central memory T (T_CM) and CD8⁺ resident memory T (T_RM) cells. It attenuated epidermal pathology and T-cell infiltration in the skin of IMQ-induced psoriatic mice while suppressing expression of IL-15, IL-17 and other proinflammatory cytokines in the skin. Surprisingly, DHA reduced the frequency and number of CD8⁺, but not CD4⁺, subset of CD44^highCD62L^high T_CM in psoriatic mice, whereas methotrexate (MTX) lowered CD4⁺, but not CD8⁺, T_CM frequency and number. Indeed, DHA, but not MTX, downregulated eomesodermin (EOMES) and BCL-6 expression in CD8⁺ T-cells. Furthermore, DHA, but not MTX, reduced the presence of CD8⁺CLA⁺, CD8⁺CD69⁺ or CD8⁺CD103⁺ T_RM cells in mouse skin. Interestingly, treatment with DHA, but not MTX, during the first onset of psoriasis largely prevented psoriasis relapse induced by low doses of IMQ two weeks later. Administration of recombinant IL-15 or CD8⁺, but not CD4⁺, T_CM cells resulted in complete recurrence of psoriasis in mice previously treated with DHA. Finally, we demonstrated that DHA alleviated psoriatic human skin lesions in humanized NSG mice grafted with lesional skin from psoriatic patients while reducing human CD8⁺ T_CM and CD103⁺ T_RM cells in humanized mice.

Conclusion: We have provided the first evidence that DHA is advantageous over MTX in preventing psoriasis relapse by reducing memory CD8⁺ T-cells.