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Particles synthesized from biodegradable polymers hold great potential as controlled drug delivery systems. Continuous flow platforms based on microfluidics offer attractive advantages over conventional batch-emulsification techniques for the scalable fabrication of drug-loaded particles with controlled physicochemical properties. However, widespread utilization of microfluidic technologies for the manufacturing of drug-loaded particles has been hindered largely by the lack of practical guidelines toward cost-effective development and reliable operation of microfluidic systems. Here, we present a framework for rational design and construction of microfluidic systems using commercially available components for high-throughput production of uniform biodegradable particles encapsulating drugs. We also demonstrate successful implementation of this framework to devise a robust microfluidic system that is capable of producing drug-carrying particles with desired characteristics. The guidelines provided in this study will likely help broaden the applicability of microfluidic technologies for the synthesis of high-quality, drug-loaded biodegradable particles.

Background: Teledermatology offers an opportunity to continually deliver care during the coronavirus disease 2019 pandemic. Objective: To provide quantitative data about the use of teledermatology. Methods: Retrospective analysis of teledermatology consultations was performed from March 16 to May 1, 2020. The number/type of encounters, differences in diagnoses, and prescriptions between asynchronous and synchronous teledermatology visits were analyzed. Results: A total of 951 visits (36.2%) were asynchronous whereas 1,672 visits (63.8%) were synchronous. Only 131 (

The COVID-19 pandemic is a serious threat to global health and the global economy. The ongoing race to develop a safe and efficacious vaccine to prevent infection by SARS-CoV-2, the causative agent for COVID-19, highlights the importance of vaccination to combat infectious pathogens. The highly accessible cutaneous microenvironment is an ideal target for vaccination since the skin harbors a high density of antigen-presenting cells and immune accessory cells with broad innate immune functions. Microarray patches (MAPs) are an attractive intracutaneous biocargo delivery system that enables safe, reproducible, and controlled administration of vaccine components (antigens, with or without adjuvants) to defined skin microenvironments. This review describes the structure of the SARS-CoV-2 virus and relevant antigenic targets for vaccination, summarizes key concepts of skin immunobiology in the context of prophylactic immunization, and presents an overview of MAP-mediated cutaneous vaccine delivery. Concluding remarks on MAP-based skin immunization are provided to contribute to the rational development of safe and effective MAP-delivered vaccines against emerging infectious diseases, including COVID-19., Graphical abstract Unlabelled Image

Astrocytes in the lamina region of the optic nerve head play vital roles in supporting retinal ganglion cell axon health. In glaucoma, these astrocytes are implicated as early responders to stressors, undergoing characteristic changes in cell function as well as cell morphology. Much of what is currently known about individual lamina astrocyte morphology has been learned from rodent models which lack a defining feature of the human optic nerve head, the collagenous lamina cribrosa (LC). Current methods available for evaluation of collagenous LC astrocyte morphology have significant shortcomings. We aimed to evaluate Multicolor DiOlistic labeling (MuDi) as an approach to reveal individual astrocyte morphologies across the collagenous LC.Gold microcarriers were coated with all combinations of three fluorescent cell membrane dyes, DiI, DiD, and DiO, for a total of seven dye combinations. Microcarriers were delivered to 150μm-thick coronal vibratome slices through the LC of pig, sheep, goat, and monkey eyes via MuDi. Labeled tissues were imaged with confocal and second harmonic generation microscopy to visualize dyed cells and LC collagenous beams, respectively. GFAP labeling of DiOlistically-labeled cells with astrocyte morphologies was used to investigate cell identity. 3D models of astrocytes were created from confocal image stacks for quantification of morphological features.DiOlistic labeling revealed fine details of LC astrocyte morphologies including somas, primary branches, higher-order branches, and end-feet. Labeled cells with astrocyte morphologies were GFAP+. Astrocytes were visible across seven distinct color channels, allowing high labeling density while still distinguishing individual cells from their neighbors. MuDi was capable of revealing tens to hundreds of collagenous LC astrocytes, in situ, with a single application. 3D astrocyte models allowed automated quantification of morphological features including branch number, length, thickness, hierarchy, and straightness as well as Sholl analysis.MuDi labeling provides an opportunity to investigate morphologies of collagenous LC astrocytes, providing both qualitative and quantitative detail, in healthy tissues. This approach may open doors for research of glaucoma, where astrocyte morphological alterations are thought to coincide with key functional changes related to disease progression.

Introduction Infectious pathogens are global disrupters. Progress in biomedical science and technology has expanded the public health arsenal against infectious diseases. Specifically, vaccination has reduced the burden of infectious pathogens. Engineering systemic immunity by harnessing the cutaneous immune network has been particularly attractive since the skin is an easily accessible immune-responsive organ. Recent advances in skin-targeted drug delivery strategies have enabled safe, patient-friendly, and controlled deployment of vaccines to cutaneous microenvironments for inducing long-lived pathogen-specific immunity to mitigate infectious diseases, including COVID-19. Areas covered This review briefly discusses the basics of cutaneous immunomodulation and provides a concise overview of emerging skin-targeted drug delivery systems that enable safe, minimally invasive, and effective intracutaneous administration of vaccines for engineering systemic immune responses to combat infectious diseases. Expert opinion In-situ engineering of the cutaneous microenvironment using emerging skin-targeted vaccine delivery systems offers remarkable potential to develop diverse immunization strategies against pathogens. Mechanistic studies with standard correlates of vaccine efficacy will be important to compare innovative intracutaneous drug delivery strategies to each other and to existing clinical approaches. Cost-benefit analyses will be necessary for developing effective commercialization strategies. Significant involvement of industry and/or government will be imperative for successfully bringing novel skin-targeted vaccine delivery methods to market for their widespread use.

Mapping the human body at single cell resolution in three-dimensions (3D) is an important step toward a “digital twin” model that captures important structure and dynamics of cell-cell interactions. Current 3D imaging methods suffer from low resolution and are limited in their ability to distinguish cell types and their spatial relationships. We present a novel 3D workflow: MATRICS-A (Multiplexed Image Three-D Reconstruction and Integrated Cell Spatial - Analysis) that generates a 3D map of cells from multiplexed images and calculates cell type distance from endothelial cells and other features of interest. We applied this workflow to multiplexed data from sequential skin sections from younger and older donors (n=10; 33-72 years) with biopsies from ten anatomical regions with different sun exposure effects (mild, moderate-marked). Up to 26 sequential sections from each sample underwent multiplexed imaging with 18 biomarkers covering 12 cell types (keratinocytes (granular, spinous, basal), epithelial and myoepithelial cells, fibroblasts, macrophages, T helpers, T killers, T regs, neurons and endothelial cells, markers of DNA damage and repair (p53, DDB2) and cell proliferation (Ki67). Following cell classification, the tissue and classified cells were reconstructed into 3D volumes. A significant inverse correlation between DDB2 positive cells and age was found (corr= -0.78, adj. p=0.047). This suggests reduced capacity for repair in non-cancer older sun-exposed individuals. While absolute immune cell count did not differ by age or sun exposure, the ratio of T Helper/T Killer cells was positively correlated with age (corr=0.82, adj. p=0.048) This is the first such 3D study in skin and paves the way for cataloging more cell types and spatial relationships in aging and disease in skin and other organs.

BackgroundDespite the remarkable benefits associated with the interventional treatment of melanomas (and other solid cancers) with immune checkpoint and Braf inhibitors (Brafi), most patients ultimately progress on therapy. The presence of multifocal/disseminated disease in patients increases their mortality risk. Hence, the development of novel strategies to effectively treat patients with melanomas that are resistant to anti-PD1 mAb (αPD1) and/or Brafi, particularly those with multifocal/disseminated disease remains a major unmet clinical need.MethodsMice developing induced/spontaneous BrafV600E/Pten−/− melanomas were treated by cutaneous immunization with a DNA vaccine encoding the melanoma-associated antigen TRP2, with Brafi or αPD1 alone, or with a combination of these treatments. Tumor progression, tumor-infiltration by CD4+ and CD8+ T cells, and the development of TRP2-specific CD8+ T cells were then monitored over time.ResultsVaccination led to durable antitumor immunity against PD1/Brafi-resistant melanomas in both single lesion and multifocal disease models, and it sensitized PD1-resistant melanomas to salvage therapy with αPD1. The therapeutic efficacy of the vaccine was associated with host skin-resident cells, the induction of a systemic, broadly reactive IFNγ+CD8+ T cell repertoire, increased frequencies of CD8+ TIL and reduced levels of PD1hi/intCD8+ T cells. Extended survival was associated with improved TIL functionality, exemplified by the presence of enhanced levels of IFNγ+CD8+ TIL and IL2+CD4+ TIL.ConclusionsThese data support the use of a novel genetic vaccine for the effective treatment of localized or multifocal melanoma refractory to conventional αPD1-based and/or Brafi-based (immune)therapy.

Objectives To determine whether physician-to-physician outpatient asynchronous store-and-forward teledermatology can be a portal for patient access to consultative dermatologic care and decrease primary care physician referrals to dermatology. Study design Retrospective study. Methods Reviewed outpatient teledermatology consults completed within a shared Epic electronic health record at the University of Pittsburgh Medical Center (UPMC) Health System between August 4, 2013, and December 19, 2019. Study data were reviewed for consult response time and triage percentage. Patient and physician experiences were collected by satisfaction surveys. Results This study reviewed 1581 teledermatology consults that originated from UPMC primary care provider (PCP) appointments. The average response time for a completed consult was 1 hour, 13 minutes for same-day consult submissions. The majority of consults, 63%, were completed online, whereas only 37% of patients were recommended for an in-person referral visit to the dermatology clinic. Surveyed patients (81%) and PCPs (90%) responded positively to their teledermatology experience. Conclusions Physician-to-physician outpatient asynchronous teledermatology consults can provide a model for rapid consultation and decreased primary care referral to dermatology.

Optimal vaccines are needed for sustained suppression of SARS‐CoV‐2 and other novel coronaviruses. Here, we developed a recombinant type 5 adenovirus vector encoding the gene for the SARS‐CoV‐2 S1 subunit antigen (Ad5.SARS‐CoV‐2‐S1) for COVID‐19 immunization and evaluated its immunogenicity in mice. A single immunization with Ad5.SARS‐CoV‐2‐S1 via S.C. injection or I.N delivery induced robust antibody and cellular immune responses. Vaccination elicited significant S1‐specific IgG, IgG1, and IgG2a endpoint titers as early as 2 weeks, and the induced antibodies were long lasting. I.N. and S.C. administration of Ad5.SARS‐CoV‐2‐S1 produced S1‐specific GC B cells in cervical and axillary LNs, respectively. Moreover, I.N. and S.C. immunization evoked significantly greater antigen‐specific T‐cell responses compared to unimmunized control groups with indications that S.C. injection was more effective than I.N. delivery in eliciting cellular immune responses. Mice vaccinated by either route demonstrated significantly increased virus‐specific neutralization antibodies on weeks 8 and 12 compared to control groups, as well as BM antibody forming cells (AFC), indicative of long‐term immunity. Thus, this Ad5‐vectored SARS‐CoV‐2 vaccine candidate showed promising immunogenicity following delivery to mice by S.C. and I.N. routes of administration, supporting the further development of Ad‐based vaccines against COVID‐19 and other infectious diseases for sustainable global immunization programs., Vaccine development against SARS‐CoV‐2 addresses the ongoing challenges posed by this pathogen and ensures preparedness for future outbreaks of coronaviruses. Subcutaneous or intranasal administration of Ad5.SARS‐CoV‐2 S1 results in multifaceted immune responses in mice, including GCs and long‐lived antibody forming cells, representing an attractive COVID‐19 vaccination strategy.

The tumor microenvironment has been compared with a nonhealing wound involving a complex interaction between multiple cell types. Schwann cells, the key regulators of peripheral nerve repair, have recently been shown to directly affect nonneural wound healing. Their role in cancer progression, however, has been largely limited to neuropathic pain and perineural invasion. In this study, we showed that melanoma activated otherwise dormant functions of Schwann cells aimed at nerve regeneration and wound healing. Such reprogramming of Schwann cells into repair-like cells occurred during the destruction and displacement of neurons as the tumor expanded and via direct signaling from melanoma cells to Schwann cells, resulting in activation of the nerve injury response. Melanoma-activated Schwann cells significantly altered the microenvironment through their modulation of the immune system and the extracellular matrix in a way that promoted melanoma growth in vitro and in vivo. Local inhibition of Schwann cell activity following cutaneous sensory nerve transection in melanoma orthotopic models significantly decreased the rate of tumor growth. Tumor-associated Schwann cells, therefore, can have a significant protumorigenic effect and may present a novel target for cancer therapy.Significance:These findings reveal a role of the nerve injury response, particularly through functions of activated Schwann cells, in promoting melanoma growth.

// Brittany O. Dulmage 1 , Oleg Akilov 1 , John R. Vu 1 , Louis D. Falo 1 , Larisa J. Geskin 2 1 Department of Dermatology, University of Pittsburgh, Pittsburgh, Pennsylvania, USA 2 Department of Dermatology, Columbia University, New York, New York, USA Correspondence to: Larisa J. Geskin, e-mail: ljg2145@columbia.edu Keywords: cutaneous T-cell lymphoma, sezary syndrome, gene expression, romidepsin, TOX Received: June 17, 2015 Accepted: September 18, 2015 Published: November 06, 2015 ABSTRACT Studies have examined gene expression changes in Sezary syndrome (SS), but disease pathogenesis remains largely unknown, and diagnosis and treatment are difficult. TOX is a transcription factor involved in CD4+ T-cell development with downstream effects on RUNX3 , a known tumor suppressor gene. We sought to identify genes involved in SS disease pathogenesis with the potential to enable diagnosis and treatment. We utilized previously reported transcriptome sequencing data to construct a list of candidate genes, which was narrowed using pathway analysis. qRT-PCR confirmed TOX upregulation (>7 fold increase) in SS ( n = 5), as well as two established markers, PLS3 and KIRD3DL2. We also evaluated expression of members of the TOX-RUNX3 pathway and confirmed downregulation of RUNX3 (0.59 fold decrease) and upregulation of GATA3 (2 fold increase). Moreover, TOX and RUNX3 expression were significantly inversely proportional. Using siRNA to suppress TOX, we demonstrated that TOX knockdown rescues RUNX3 expression and reduces cell viability. We evaluated TOX protein expression in paraffin-embedded skin biopsies with immunohistochemistry, showing nuclear staining of CTCL infiltrates, suggesting it is a candidate diagnostic biomarker. Further studies validating our findings and evaluating the TOX-RUNX3 pathway and the role of TOX as a disease marker and therapeutic target are warranted.

BACKGROUND: Allergic contact dermatitis (CD) is a chronic inflammatory skin disease caused by type-1 biased adaptive immunity for which there is an unmet need for antigen (Ag)-specific immunotherapies. Exposure to skin sensitizers stimulates secretion of the proinflammatory neuropeptides substance P (SP) and hemokinin 1 (HK1), which signal via the neurokinin-1 receptor (NK1R) to promote the innate and adaptive immune responses of CD. Accordingly, mice lacking the NK1R develop impaired CD. Nonetheless, the role and therapeutic opportunities of targeting the NK1R in CD remain to be elucidated. OBJECTIVE: To develop an Ag-specific immunosuppressive approach to treat CD by skin co-delivery of hapten and NK1R antagonists integrated in dissolvable microneedle arrays (MNA). METHODS: In vivo mouse models of contact hypersensitivity and ex-vivo models of human skin were used to delineate the effects and mechanisms of NK1R-signaling and the immunosuppressive effects of the contact sensitizer-NK1R-antagonists-MNA in CD. RESULTS: We demonstrate in mice that CD requires NK1R signaling by SP and HK1. Specific deletion of the NK1R in keratinocytes and dendritic cells, but not in mast cells prevented CD. Skin co-delivery of hapten- or Ag-NK1R-antagonist-MNA inhibited neuropeptide-mediated skin inflammation in mouse and human skin, promoted deletion of Ag-specific effector T cells and increased regulatory T cells, which prevented CD onset and relapses locally and systemically in an Ag-specific manner. CONCLUSIONS: Our findings demonstrate that immune-regulation by engineering localized skin neuroimmune networks can be used to treat cutaneous diseases that like CD, are caused by type-1 immunity.

Background Excessive UV radiation disrupts skin homeostasis by multiple mechanisms that extend beyond the simple erythema associated with sunburns including reduction of antioxidants, increased DNA damage, and impairment of skin immune responses. Recreational UV exposure frequently occurs concurrently with excessive ethanol (EtOH). Epidemiological studies suggest a harmful, dose-dependent impact of EtOH in the setting of high UV exposure, leading to increased severity of sunburns relative to those generated in the absence of ethanol. Furthermore, EtOH consumption and UV radiation have multiple overlapping effects on the skin that could account for the epidemiological association. Objective To elucidate the relationship between excessive EtOH ingestion and UV exposures on early skin damage and downstream immune dysfunction. Methods We examined the impact of UVB on local skin damage, including inflammation, sunburned cells, apoptotic cells, melanin and antioxidant levels, DNA damage and immune dysfunction in the presence or absence of EtOH ingestion by combining standard mouse models of EtOH consumption and UVB exposure models. To confirm that the observed changes in mouse skin were relevant to human skin, we investigated the effects of EtOH on UV-induced skin damage with human skin explants. Results We demonstrated that EtOH consumption and UV exposure act synergistically to increase the severity of local skin damage resulting in impaired melanin responses, reduced antioxidants, greater DNA damage, and immune dysfunction as measured by reduced contact hypersensitivity. Conclusions The results support incorporation of the risks of combined UV exposure and excessive alcohol consumption into public health campaigns.

Dengue virus (DENV) and Zika virus (ZIKV) are closely related mosquito-borne flaviviruses that co-circulate in tropical regions and constitute major threats to global human health. Whether preexisting immunity to one virus affects disease caused by the other during primary or secondary infections is unknown but is critical in preparing for future outbreaks and predicting vaccine safety. Using a human skin explant model, we show that DENV-3 immune sera increased recruitment and infection of Langerhans cells, macrophages, and dermal dendritic cells following inoculation with DENV-2 or ZIKV. Similarly, ZIKV immune sera enhanced infection with DENV-2. Immune sera increased migration of infected Langerhans cells to the dermis and emigration of infected cells out of skin. Heterotypic immune sera increased viral RNA in the dermis almost 10-fold and reduced the amount of virus required to infect a majority of myeloid cells by 100- to 1000-fold. Enhancement was associated with cross-reactive IgG and induction of IL-10 expression and was mediated by both CD32 and CD64 Fcγ receptors. These findings reveal that preexisting heterotypic immunity greatly enhances DENV and ZIKV infection, replication, and spread in human skin. This relevant tissue model will be valuable in assessing the efficacy and risk of dengue and Zika vaccines in humans.

OBJECTIVES: In the current era of checkpoint inhibitors, some patients with metastatic melanoma have demonstrated a significant improvement in survival. However, optimization of immunotherapy is an ongoing effort. Monocyte-derived dendritic cell (MODC) vaccines have been shown in clinical trials to be safe and capable of inducing tumor-specific immunity as well as occasional objective clinical responses. Here we conducted a three-arm pilot clinical study in 15 patients with metastatic melanoma to evaluate three types of MODC vaccines, differing only by strategies of tumor antigen delivery. METHODS: MODCs were isolated from each patient and loaded with patients’ own melanoma cells as sources of antigens. Antigen loading was achieved ex vivo by fusing melanoma cells with MODCs, co-culturing melanoma cells with MODCs, or by pulsing MODCs with melanoma cell lysates. The vaccines were then injected into superficial lymph nodes using high-resolution ultrasound guidance. Primary endpoints included delayed-type hypersensitivity (DTH) responses and positive ELISpot, which measures IFN-gamma production. RESULTS: 5 of 15 patients achieved DTH responses and 6 of 15 had positive ELISpots. We demonstrated that the vaccines were safe and well-tolerated by all patients and produced immunological responses in all arms. CONCLUSION: Although MODC vaccine monotherapy has limited efficacy, combining this vaccine with other immunotherapies, such as checkpoint inhibitors, in order to engage multiple components of the immune system may be an effective and viable future approach.

Endogenous electrophilic fatty acids mediate anti-inflammatory responses by modulating metabolic and inflammatory signal transduction and gene expression. Nitro-fatty acids and other electrophilic fatty acids may thus be useful for the prevention and treatment of immune-mediated diseases, including inflammatory skin disorders. In this regard, subcutaneous (SC) injections of nitro oleic acid (OA-NO2), an exemplary nitro-fatty acid, inhibit skin inflammation in a model of allergic contact dermatitis (ACD). Given the nitration of unsaturated fatty acids during metabolic and inflammatory processes and the growing use of fatty acids in topical formulations, we sought to further study the effect of nitro-fatty acids on cutaneous inflammation. To accomplish this, the effect of topically applied OA-NO2 on skin inflammation was evaluated using established murine models of contact hypersensitivity (CHS). In contrast to the effects of subcutaneously injected OA-NO2, topical OA-NO2 potentiated hapten-dependent inflammation inducing a sustained neutrophil-dependent inflammatory response characterized by psoriasiform histological features, increased angiogenesis, and an inflammatory infiltrate that included neutrophils, inflammatory monocytes, and γδ T cells. Consistent with these results, HPLC-MS/MS analysis of skin from psoriasis patients displayed a 56% increase in nitro-conjugated linoleic acid (CLA-NO2) levels in lesional skin compared to non-lesional skin. These results suggest that nitro-fatty acids in the skin microenvironment are products of cutaneous inflammatory responses and, in high local concentrations, may exacerbate inflammatory skin diseases.

Skin-targeted drug delivery is broadly employed for both local and systemic therapeutics and is an important tool for discovery efforts in cutaneous biology. Recently, emerging technologies support efforts toward skin-targeted biocargo delivery for local and systemic therapeutic benefit. Effective targeting of bioactive molecules, including large (molecular weight > 500 Da) or complex (hydrophilic and charged) molecules, to defined cutaneous microenvironments is intrinsically challenging owing to the protective barrier function of the skin. Dissolvable microneedle arrays (MNAs) have proven to be a promising technology to address the unmet need for controlled, minimally invasive, and reliable delivery of a wide range of biocargos to the skin. In this paper, we describe the unique properties of the skin that make it an attractive target for vaccine delivery, for immune-modulating therapies, and for systemic drug delivery and the structural characteristics of the skin that present obstacles to efficient intracutaneous and transdermal delivery of bioactive molecules. We provide an overview of MNA fabrication and the characteristics and mechanisms of dissolvable MNA cargo delivery to the cutaneous microenvironment. We present a representative example of a clinical application of MNAs and discuss future directions for MNA development and applications.

Psoriasis is a chronic inflammatory skin disease with no cure. Although the origin of psoriasis and its underlying pathophysiology remain incompletely understood, inflammation is a central mediator of disease progression. In this regard, electrophilic nitro-fatty acids (NO2–FAs) exert potent anti-inflammatory effects in several in vivo murine models of inflammatory diseases, such as chronic kidney disease and cardiovascular disease. To examine the therapeutic potential of NO2–FAs on psoriasiform dermatitis, we employed multiple murine models of psoriasis. Our studies demonstrate that oral treatment with nitro oleic acid (OA-NO2) has both preventative and therapeutic effects on psoriasiform inflammation. In line with this finding, oral OA-NO2 downregulated the production of inflammatory cytokines in the skin. In vitro experiments demonstrate that OA-NO2 decreased both basal IL-6 levels and IL-17A-induced expression of IL-6 in human dermal fibroblasts through the inhibition of NF-κB phosphorylation. Importantly, OA-NO2 diminished STAT3 phosphorylation and nuclear translocation via nitroalkylation of STAT3, which inhibited keratinocyte proliferation. Overall, our results affirm the critical role of both NF-κB and STAT3 in the incitement of psoriasiform dermatitis and highlight the pharmacologic potential of small molecule nitroalkenes for the treatment of cutaneous inflammatory diseases, such as psoriasis., Graphical abstract Image 1, Highlights • Oral OA-NO2 has a therapeutic effect on inflammation in murine models of psoriasis. • Cutaneous inflammatory cytokines are suppressed following oral OA-NO2 treatment. • OA-NO2 decreases basal and IL-17A-induced IL-6 expression in vitro. • OA-NO2 diminishes STAT3 activation through nitroalkylation of STAT3.

The skin is an attractive tissue target for vaccination, as it is readily accessible and contains a dense population of antigen-presenting and immune-accessory cells. Microneedle arrays (MNAs) are emerging as an effective tool for in situ engineering of the cutaneous microenvironment to enable diverse immunization strategies. Here, we present novel dissolving undercut MNAs and demonstrate their application for effective multicomponent cutaneous vaccination. The MNAs are composed of micron-scale needles featuring pyramidal heads supported by undercut stem regions with filleted bases to ensure successful skin penetration and retention during application. Prior efforts to fabricate dissolving undercut microstructures were limited and required complex and lengthy processing and assembly steps. In the current study, we strategically combine three-dimensional (3D) laser lithography, an emerging micro-additive manufacturing method with unique geometric capabilities and nanoscale resolution, and micromolding with favorable materials. This approach enables reproducible production of dissolving MNAs with undercut microneedles that can be tip-loaded with multiple biocargos, such as antigen (ovalbumin) and adjuvant (Poly(I:C)). The resulting MNAs fulfill the geometric (i.e., sharp tips and smooth edges) and mechanical-strength requirements for failure-free penetration of human and murine skin to simultaneously deliver multicomponent (antigen plus adjuvant) vaccines to the same cutaneous microenvironment. Cutaneous vaccination of mice using these MNAs induces more potent antigen-specific cellular and humoral immune responses than those elicited by traditional intramuscular injection. Together, the unique geometric features of these undercut MNAs and the associated manufacturing strategy, which is compatible with diverse drugs and biologics, could enable a broad range of non-cutaneous and cutaneous drug delivery applications, including multicomponent vaccination.

Background: Currently, the number of inpatient dermatology providers cannot meet the overall burden of inpatient skin disease in the United States. Introduction: We seek to determine whether inpatient eDermatology can meet the need for inpatient skin disease in hospitals without access to a dermatology hospitalist. Methods: This retrospective cohort study reviewed inpatient eDermatology consults at the University of Pittsburgh eDermatology Consult Service between July 1, 2014 and June 30, 2018. This included a diverse group of 1,320 patients admitted to 10 different community hospitals. Study data were reviewed for demographics, diagnostic impressions, time to discharge, and diagnostic discordance between referring and consultant physicians. Results: Forty percent of inpatient eDermatology consults were admitted with a primary dermatologic diagnosis. Referring diagnosis most commonly was rash not otherwise specified. eDermatology consulting impressions, conversely, were specific and varied. Ninety-one percent of patients received a consultant impression by the end of day, or within 8 hours. Overall, 89.3% of patients with a referring diagnosis of "cellulitis" were given a different diagnosis by the consultant. Discussion: Although this study lacked concordance data to compare the Inpatient eDermatologist with a live Inpatient Dermatologist, overall, eDermatology consultants were able to provide rapid consult recommendations that aided patient management. Conclusions: Inpatient eDermatology appears to be an effective medium to provide dermatologic care to patients at hospitals without a dermatology presence. This delivery of health care can help prevent misdiagnosis, unnecessary costs, and inappropriate systemic therapies.

The activation of T helper 17 signaling plays a critical role in psoriasis pathogenesis, and systemically-administered IL-17 inhibitors are highly effective therapy for moderate-to-severe disease. We generated topically-delivered gene-regulating nanoconstructs, comprised of spherically-arrayed antisense DNA (liposomal spherical nucleic acids [L-SNAs]), which are able to penetrate human skin to knock down cutaneous gene targets. Topically-applied L-SNAs targeting the gene encoding the mouse IL-17A receptor (Il17ra) reversed the development of psoriasis clinically, histologically, and transcriptionally in imiquimod-treated psoriasis-like mouse skin. Il17ra L-SNAs reduced the modified PASI by 74% versus controls and decreased epidermal thickness by 56%. Il17ra L-SNA reduced Il17ra protein expression by 75% and significantly decreased the mRNA expression of psoriasis markers, including Defb4, Il17c, S100a7, Pi3, Krt16, and Tnfa versus scrambled spherical nucleic acid (Scr SNA) controls. A human IL17RA L-SNA penetrates 3-dimensional cultures and normal human explants to knock down IL17RA mRNA by 63% and 66%, respectively. After topical application to psoriatic 3-dimensional rafts, anti-human IL17RA L-SNAs reduced the expression of IL17RA (by 72%) and the IL-17-induced genes IL17C (by 85%), DEFB4 (by 83%), TNFA (by 77%), and PI3 (by 65%) versus scrambled L-SNA and vehicle controls (all P < 0.001). Taken together, these data suggest that targeted suppression of IL17RA is a promising new topical treatment strategy for psoriasis.

Cutaneous mast cells (MCs) reside in close proximity to peripheral sensory nerve fibers and are susceptible to regulation by neuropeptides. The tachykinin family member, Neurokinin A (NKA) binds with highest affinity to the Neurokinin 2 Receptor, expressed on MCs. MCs are poised to respond to NKA, but its role in the MC biology is, to our knowledge, under-explored. The objective of this study was to evaluate the effects of NKA on bone marrow (BM) MCs and peritoneal (P)MCs in vitro and in the murine model of passive cutaneous anaphylaxis (PCA) in vivo. Neurokinin A inhibited FceRI-initiated phosphorylation and nuclear localization of STAT5, and release of TNF and IL-13 in an IL-10-dependent manner. NKA affected the MC secretome, abrogating ABCA1-dependent release of the cysteine protease, calpain. Extracellular calpain, in turn, degraded IL-10. In vivo, NKA administration reduced PCA, inhibiting edema, and induction of inflammatory cytokines and in a manner that relied on MC derived-IL-10. Likewise, direct inhibition of the ABCA1 phenocopied the effects of NKA, reducing IgE-initiated MC responses in vitro and in vivo. In conclusion, NKA minimizes IgE-initiated inflammation though an IL-10-dependent mechanism and inhibits ABCA1-dependent release of the IL-10 degrading enzyme, calpain. This study illuminates a novel tier of neuropeptide mediated MC regulation through the ABCA1. Strategies interfering with the ABCA1 may be promising therapeutics for targeting MCs in cutaneous inflammatory diseases.

Contact dermatitis (CD) is a chronic inflammatory disease caused by type-1 immunity. Skin exposure to haptens stimulates the secretion of Substance-P (SP) and initiates the neurogenic inflammation that intensifies CD. Neurokinin-1 receptor (NK1R)-signaling by SP or hemokinin-1 (HK1) amplifies immune responses. Nonetheless, the role and therapeutic implications of the NK1R-SP-HK1 axis in CD remain unclear. We show that SP, HK-1 and the NK1R are required for CD. Specific deletion of the NK1R in keratinocytes decreased the rapid release of IL-1β and IL-6 at the site of contact sensitization which impaired the innate and adaptive immunity of CD whereas deletion of the receptor in dendritic cells (DC) prevented only the adaptive immune response of the disease. Therefore, we hypothesized that blockade of NK1R during sensitization would be a feasible immunosuppressive intervention to treat CD. We developed a system of microneedle arrays (MNA) that co-deliver hapten and NK1R antagonists into mouse skin. This immunosuppressive approach resulted in decreased skin migration and lymph node homing of stimulatory dermal DC transporting the hapten from the sensitization site. Conversely, the immunosuppressive MNA did not affect the migration and lymph node homing of epidermal Langerhans cells (LC), and depletion of LC resulted in loss of the NK1R antagonist beneficial effects. In addition, immunosuppressive MNA caused deletion of hapten-specific T cells and increased T-regulatory cells, which prevented CD-onset and -relapses in a hapten-specific manner. Our findings indicate that immune-regulation by engineering localized skin neuroimmune-networks can be used to treat cutaneous diseases that, like CD are caused by type-1 immunity.

Considerable progress has been made toward development of COVID-19 vaccines in the past year However, there is still a need for painless, self-administered, shelf-stable, and efficacious SARS-CoV-2 vaccines to enable sustainable immunization programs against COVID-19 To address this need, we hypothesized that harnessing the immune-responsive cutaneous microenvironment using microarray patches (MAPs) to deliver integrated SARS-CoV-2 vaccine components would bring together biologic advantages of targeting the endogenous immune circuitry of the skin with a thermostable and user-friendly cutaneous vaccine delivery platform We show that immunologically rich cutaneous microenvironments in both murine and human skin can be efficiently targeted using our 3D printing-enabled dissolving MAPs to deliver a recombinant SARS-CoV-2 protein antigen, with or without an innate immune agonist Immunization of mice with vaccine-loaded MAPs generates robust antibody and cellular immune responses, and multicomponent (antigen plus adjuvant) MAP vaccination improves the induced antigen-specific immune responses, such as virus-specific Th1 and IgG2c responses, which are vital for control of SARS-CoV-2 viral infection Notably, multicomponent MAP vaccination results in increased immune responses compared to immunization via traditional intramuscular injection, and MAP immunization obviates adverse effects of intramuscular delivery of adjuvants, suggesting improved safety and efficacy compared to conventional vaccination routes These results are supported by our translational studies utilizing freshly-excised human skin, suggesting that multicomponent MAPs induce greater expression of co-stimulatory molecules by human skin-migratory DCs, which may contribute to enhanced immune responses Ultimately, the simplicity, thermostability, immunogenicity, and versatility of MAPs may enable novel vaccination strategies and increase the effectiveness of global immunization campaigns against SARS-CoV-2 and other existing or novel pathogens

Blockade of immune checkpoint PD1 in cancer patients results in remarkable therapeutic benefits. Revealing mechanisms underlying this revolutionary therapy is critical to identifying biomarkers for predicting responses to this treatment and developing novel PD1 blockade combined therapeutic regimens for broader clinical efficacy. Rejuvenation of preexisting intratumoral ‘exhausted’ T cells and recruitment of peripheral antitumor T cells into tumors have been suggested to explain how PD1 blockade works, but mechanisms of action of anti-PD1 therapy remain to be fully delineated. In a clinically relevant mouse model of spontaneous metastatic breast cancer 4T1.2-Neu, we show that effective and durable anti-PD1 therapy depends on systemic immunity, including type 1 conventional dendritic cells (cDC1: CD8α+/CD103+DC), B cells, CD4 and CD8 T cells. Increased circulating and/or tumor-infiltrating IL12+CD103+DC and IL2+CD4/CD8 T cells are associated with the response to anti-PD1 therapy. PD1 blockade results in tumor-primed CD44+IL2+CD4T cells in the periphery regardless of cDC1. In the breast cancer model with adoptive cell transfer (ACT), PD1 blockade-driven CD44+CD4+T cells infiltrate into tumors and ignite protective immunity against new tumors in an IL2-dependent and tumor-specific manner. In a distinct ACT model using enforced IL2-expressing melanoma antigen specific TRP1-transgenic (Tg) CD4 T cells, IL2+TRP1-Tg CD4 T cells control the growth of PD1-resistant endogenous BP or B16 melanoma. These data suggest the prominent role of PD1 blockade on the effectiveness of tumor-primed CD4T cells in tumor-specific immunity.

Autoinflammatory skin diseases are characterized by a disequilibrium of cytokines in the local skin microenvironment, suggesting that local delivery of therapeutics, including anticytokine antibodies, may provide benefit without the unwanted off-target effects of systemically delivered therapies. Rapid diffusion of therapeutics away from the target site has been a challenge to the development of local therapies. Conjugation of high molecular weight hydrophilic polymers to cytokine neutralizing mAbs has been shown to be an effective strategy for local control of inflammation in healing burn wounds. However, the burn application is unique because the skin barrier is already breached. For the treatment of autoinflammatory skin diseases, the major challenge for local delivery lies in penetrating the stratum corneum. Here, we investigate a new therapeutic approach combining the use of tip-loaded dissolvable microneedle arrays (TL-dMNAs) for local application of polymer-conjugated antibody inhibitors of tumor-necrosis-factor-alpha (TNF-α). Specifically, intradermal delivery and pharmacokinetics of (anti-TNF-α-Ab)-(high molecular weight hyaluronic acid [HA]) conjugates from tip-loaded, obelisk-shaped dissolvable microneedle arrays were investigated in living human skin. The results indicate (1) TL-dMNAs can be successfully fabricated to integrate (anti-TNF-α-Ab)-HA at the tip portion of the microneedles while preserving the biological activity necessary for antibody ligand binding; (2) (anti-TNF-α-Ab)-HA can be effectively delivered into human skin using obelisk-shaped TL-dMNAs; and (3) polymer conjugation effectively inhibits antibody diffusion from the delivery site. Taken together, these results support the evaluation of microneedle array-based delivery of varying polymer-antibody conjugates for the treatment of inflammatory skin diseases.

Despite the remarkable treatment benefits associated with interventional checkpoint blockade for solid tumors, many patients ultimately progress on therapy. The development of novel strategies that can overcome resistance to checkpoint therapy remains a considerable unmet clinical need. In this context, we developed a novel tumor immunization strategy that is multifunctional and combines co-delivery of plasmid DNA encoding antigen and molecules driving immunostimulatory function and antigen targeting. Specifically, we targeted expression of plasmid DNA encoding the stress response transcription factor XBP1 and the melanoma-associated antigen TRP2 fused to heat shock protein HSP70. Transient skin-localized expression promotes a pro-immunogenic skin microenvironment and the induction, recruitment, and maintenance of Type-1 cytotoxic CD8 T cells (Tc1), including Tc1 T-cell infiltrates within the tumor microenvironment (TME), and tumor regression in a PD1-resistant mouse melanoma model. These data suggest a novel therapeutic strategy in which combined effects of localized XBP1 and HSP70 antigen conjugation establishes a PD1-responsive TME for effective and durable treatment of PD1-resistant cancers. Citation Format: Louis D. Falo. Skin-targeted combinatorial DNA immunization overcomes tumor resistance to PD1 therapy [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 5565.

Psoriasis is a systemic, immune-mediated disorder, characterized by chronic inflammatory skin and joint manifestations. Electrophilic nitro-fatty acids (NO2-FAs) have been reported to exert potent anti-inflammatory effects in several in vivo murine models of inflammatory diseases, such as chronic kidney disease and cardiovascular disease. To study the therapeutic potential of NO2-FAs on psoriasis, we employed both acute and chronic murine experimental models of psoriasis. Our studies demonstrate that oral treatments of nitro-oleic acid (OA-NO2), prior to imiquimod (IMQ) or rIL-23 treatments, significantly inhibited the induction of psoriasis-like inflammation and inflammatory cytokine production in the skin. Moreover, utilizing transgenic murine models of psoriasis, we determined that OA-NO2 had both a preventative and therapeutic effect on psoriasiform inflammation. Mechanistic in vitro experiments demonstrated that OA-NO2 decreased IL-17A-induced IL-6 expression in normal human dermal fibroblasts through the inhibition of NF-κB phosphorylation. Importantly, OA-NO2 also impaired signal transducers and activators of transcription 3 (STAT3) phosphorylation and translocation to the nucleus. Further mechanistic results indicated that OA-NO2 regulates STAT3 activation by post-translational modification of STAT3 via nitroalkylation. Overall, our results confirm the critical role of STAT3 in psoriasiform dermatitis and highlight the potential of NO2-FAs as therapeutic agents for the treatment of cutaneous inflammatory diseases, such as psoriasis.

Within the skin, mast cells (MCs) and sensory neurons form a cohesive unit that plays an important role in initiating immune responses. Neuropeptides such as neurokinin A and substance P direct MC function by initiating signaling through neurokinin (NK) receptors, and Mas related G-protein receptors (Mrgpr)s. Neurokinin A, in particular, is thought to signal through the NK2R. Recent studies highlight the importance of the MrgprB2 (mouse) and MrgprX2 (human) in the MC response to pseudo-allergens, secretagogues and substance P. To date, a relationship between neurokinin receptors and the MrgprB2/X2 has not been investigated. In this study, we hypothesize that MrgprB2/X2 expression is controlled by the NK2R and its high affinity ligand, neurokinin A. In mice, we show that administration of neurokinin A diminishes MrgprB2 expression. Surprisingly, antagonism of the NK2R also downregulates MrgprB2 expression and in NK2R-deficient mice, MrgprB2 expression is markedly diminished. In contrast, co-administration of neurokinin A and a NK2R antagonist markedly increases MrgprB2 expression. In human skin explants, NK2R antagonism has minimal effect on MrgprX2 expression, but co-administration of neurokinin A and a NK2R antagonist upregulates MrgprX2 expression, as seen in murine skin. These data demonstrate that NK2R-signaling influences MrgprB2/X2 expression and, in absence of the NK2R, neurokinin A interacts with an unknown receptor to increase MrpgrB2/X2 expression. Collectively, these data uncover a novel role for NK2R signaling in the regulation of MrgprB2/X2. These important findings have implications for patients with dysregulated mast cell function initiated through the MrgprX2.

Substance P (SP) is a proinflammatory neuropeptide that following Ag entrance in peripheral tissues signals via the neurokinin 1 receptor (NK1R) to initiate innate and support adaptive cellular immune responses. These mechanisms underlie chronic skin inflammatory disorders like contact dermatitis (CD). Here we propose to develop an immunosuppressive method to prevent and treat CD by blocking the effects of SP during skin sensitization with haptens. We utilized microneedle arrays to efficiently deliver the hapten 2,4-dinitrocholorobencene (DNCB) and NK1R antagonists simultaneously to the skin of C57/BL6 mice. This approach, restrained neuroinflammation, increased T regulatory cells and decreased the viability of Th1 and Tc1 biased cells in the draining lymph nodes. Together these effects inhibited local and systemic CD and prevented its relapses. Using the Cre-Lox P system, we demonstrate that specific deletion of the NK1R in keratinocytes but not in leukocytes inhibited the sensitization phase of CD by blocking the release of IL-1β and IL-6. Whereas deletion of the receptor in keratinocytes or in dendritic cells was necessary to abrogate the adaptive cellular immunity. Our data demonstrate the possibility of preventing the development of cellular immunity by engineering the skin microenvironment to restrain the effects of neuroinflammatory peptides accounting for the onset of chronic skin inflammatory diseases.

Background Coronaviruses pose a serious threat to global health as evidenced by Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and COVID-19. SARS Coronavirus (SARS-CoV), MERS Coronavirus (MERS-CoV), and the novel coronavirus, previously dubbed 2019-nCoV, and now officially named SARS-CoV-2, are the causative agents of the SARS, MERS, and COVID-19 disease outbreaks, respectively. Safe vaccines that rapidly induce potent and long-lasting virus-specific immune responses against these infectious agents are urgently needed. The coronavirus spike (S) protein, a characteristic structural component of the viral envelope, is considered a key target for vaccines for the prevention of coronavirus infection. Methods We first generated codon optimized MERS-S1 subunit vaccines fused with a foldon trimerization domain to mimic the native viral structure. In variant constructs, we engineered immune stimulants (RS09 or flagellin, as TLR4 or TLR5 agonists, respectively) into this trimeric design. We comprehensively tested the pre-clinical immunogenicity of MERS-CoV vaccines in mice when delivered subcutaneously by traditional needle injection, or intracutaneously by dissolving microneedle arrays (MNAs) by evaluating virus specific IgG antibodies in the serum of vaccinated mice by ELISA and using virus neutralization assays. Driven by the urgent need for COVID-19 vaccines, we utilized this strategy to rapidly develop MNA SARS-CoV-2 subunit vaccines and tested their pre-clinical immunogenicity in vivo by exploiting our substantial experience with MNA MERS-CoV vaccines. Findings Here we describe the development of MNA delivered MERS-CoV vaccines and their pre-clinical immunogenicity. Specifically, MNA delivered MERS-S1 subunit vaccines elicited strong and long-lasting antigen-specific antibody responses. Building on our ongoing efforts to develop MERS-CoV vaccines, promising immunogenicity of MNA-delivered MERS-CoV vaccines, and our experience with MNA fabrication and delivery, including clinical trials, we rapidly designed and produced clinically-translatable MNA SARS-CoV-2 subunit vaccines within 4 weeks of the identification of the SARS-CoV-2 S1 sequence. Most importantly, these MNA delivered SARS-CoV-2 S1 subunit vaccines elicited potent antigen-specific antibody responses that were evident beginning 2 weeks after immunization. Interpretation MNA delivery of coronaviruses-S1 subunit vaccines is a promising immunization strategy against coronavirus infection. Progressive scientific and technological efforts enable quicker responses to emerging pandemics. Our ongoing efforts to develop MNA-MERS-S1 subunit vaccines enabled us to rapidly design and produce MNA SARS-CoV-2 subunit vaccines capable of inducing potent virus-specific antibody responses. Collectively, our results support the clinical development of MNA delivered recombinant protein subunit vaccines against SARS, MERS, COVID-19, and other emerging infectious diseases.

Despite the remarkable treatment benefits associated with interventional checkpoint PD1 blockade in cancer, most patients ultimately progress on therapy. Revealing mechanisms underlying tumors responsive to PD1 blockade is critical to identifying biomarkers for predicting responses to PD1 therapy and developing novel PD1 combined therapeutic regimens for their broad use in clinic. In a clinically reflective mouse model of spontaneous metastatic breast carcinoma, effective and durable PD1 therapy is dependent on systemic immunity including Type 1 conventional dendritic cells (cDC1: CD8α+DC/CD103+DC), B cells, CD4 T cells, and CD8 T cells. Increased circulating and/or tumor-infiltrating IL12+CD103+DC and IL2+CD4/CD8 T cells are associated with tumors responsive to PD1 therapy. PD1 blockade results in tumor-primed CD44+IL2+CD4 T cells in the periphery regardless of cDC1. Adoptive transfer of PD1 blockade-driven CD44+CD4 T cells ignites protective immunity against new tumors. Neutralization of IL2 post the adoptive transfer abrogates the antitumor immunity. These data suggest the prominent role of PD1 blockade on tumor-primed CD4 T cells in newly induced T cells via cDC1 in response to PD1 therapy. Citation Format: Xingxing Hao, Louis D. Falo III, Guo Chen, Cara D. Carey, Louis D. Falo Jr., Zhaoyang You. Blockading PD1 on tumor-primed CD4 T cells instigates antitumor immunity [abstract]. In: Proceedings of the AACR Special Conference on Tumor Immunology and Immunotherapy; 2019 Nov 17-20; Boston, MA. Philadelphia (PA): AACR; Cancer Immunol Res 2020;8(3 Suppl):Abstract nr A37.