Safety of Bimekizumab for Plaque Psoriasis: An Expert Consensus Panel.

BACKGROUND: Plaque psoriasis is a chronic, relapsing systemic illness that has a significant effect on quality of life. Bimekizumab is the first monoclonal antibody to target both interleukin (IL)-17A and IL-17F, and recently received Food and Drug Administration (FDA) approval for moderate to severe plaque psoriasis. Guidance is necessary regarding the safety of bimekizumab. METHODS: A comprehensive literature search of PubMed, Scopus, and Google Scholar was completed for English-language original research articles on the safety of bimekizumab for moderate to severe psoriasis. A panel of 9 dermatologists and 1 rheumatologist with significant expertise in the treatment of psoriasis gathered to review the articles and create consensus statements on this new medication. A modified Delphi process was used to approve each statement, and strength of recommendation was assigned using the Strength of Recommendation Taxonomy criteria. RESULTS: The literature search produced 110 articles that met the criteria. A thorough screening of the studies for relevance to the research question resulted in 15 articles. These were distributed to all panelists for review prior to a roundtable discussion. The panel unanimously voted to adopt 5 consensus statements and recommendations, all of which were given a strength of "A". CONCLUSION: Bimekizumab has a safety profile consistent with other biologics, except for a higher risk of oral candidiasis. Its hepatic safety profile is comparable with other currently FDA-approved biologics for plaque psoriasis. In addition, the data do not support an association of bimekizumab with suicide, and the incidence of inflammatory bowel disease is not greater than the incidence of other IL-17 blockers. J Drugs Dermatol. 2024;23(8):592-599. doi:10.36849/JDD.8246.

Gut-derived memory γδ T17 cells exacerbate sepsis-induced acute lung injury in mice.

Sepsis is a critical global health concern linked to high mortality rates, often due to acute lung injury (ALI)/acute respiratory distress syndrome (ARDS). While the gut-lung axis involvement in ALI is recognized, direct migration of gut immune cells to the lung remains unclear. Our study reveals sepsis-induced migration of γδ T17 cells from the small intestine to the lung, triggering an IL-17A-dominated inflammatory response in mice. Wnt signaling activation in alveolar macrophages drives CCL1 upregulation, facilitating γδ T17 cell migration. CD44+ Ly6C- IL-7Rhigh CD8low cells are the primary migratory subtype exacerbating ALI. Esketamine attenuates ALI by inhibiting pulmonary Wnt/ß-catenin signaling-mediated migration. This work underscores the pivotal role of direct gut-to-lung memory γδ T17 cell migration in septic ALI and clarifies the importance of localized IL-17A elevation in the lung.

Rapid Remission of Plaque Psoriasis With Bimekizumab Treatment.

Bimekizumab is a novel humanized bispecific monoclonal immunoglobulin G1 (IgG1) antibody that dually inhibits both IL-17A and IL-17F. Investigation of the pivotal role of IL-17A, and more recently, IL-17F, in the pathogenesis of psoriasis has underscored the utility of biologics targeting these cytokines in the treatment of the disease. Treatments include the anti-IL-17 biologics specifically targeted against IL-17A (secukinumab and ixekizumab) or its receptor (brodalumab). Recent clinical trials proved the efficacy and safety of bimekizumab in the treatment of moderate-to-severe plaque psoriasis and even showed it to be superior to other psoriasis biologic treatments in regards to efficacy and rapidity of response. These are important factors to consider when discussing treatment options with patients as psoriasis patients commonly desire fast-acting results. In this case, we describe clearance of moderate-to-severe plaque psoriasis within 72 hours of treatment with bimekizumab, one of the fastest reported clearance times in the medical literature. J Drugs Dermatol. 2024;23(8):694-696. doi:10.36849/JDD.8381.

Role of the type 3 cytokines IL-17 and IL-22 in modulating metabolic dysfunction-associated steatotic liver disease.

Metabolic dysfunction-associated steatotic liver disease (MASLD) comprises a spectrum of liver diseases that span simple steatosis, metabolic dysfunction-associated steatohepatitis (MASH) and fibrosis and may progress to cirrhosis and cancer. The pathogenesis of MASLD is multifactorial and is driven by environmental, genetic, metabolic and immune factors. This review will focus on the role of the type 3 cytokines IL-17 and IL-22 in MASLD pathogenesis and progression. IL-17 and IL-22 are produced by similar adaptive and innate immune cells such as Th17 and innate lymphoid cells, respectively. IL-17-related signaling is upregulated during MASLD resulting in increased chemokines and proinflammatory cytokines in the liver microenvironment, enhanced recruitment of myeloid cells and T cells leading to exacerbation of inflammation and liver disease progression. IL-17 may also act directly by activating hepatic stellate cells resulting in increased fibrosis. In contrast, IL-22 is a pleiotropic cytokine with a dominantly protective signature in MASLD and is currently being tested as a therapeutic strategy. IL-22 also exhibits beneficial metabolic effects and abrogates MASH-related inflammation and fibrosis development via inducing the production of anti-oxidants and anti-apoptotic factors. A sex-dependent effect has been attributed to both cytokines, most importantly to IL-22 in MASLD or related conditions. Altogether, IL-17 and IL-22 are key effectors in MASLD pathogenesis and progression. We will review the role of these two cytokines and cells that produce them in the development of MASLD, their interaction with host factors driving MASLD including sexual dimorphism, and their potential therapeutic benefits.

Role of Interleukin-17 cytokine family in human T-cell lymphotropic virus type 1 (HTLV-1) infection and associated diseases.

BACKGROUND: Human T-lymphotropic virus (HTLV-1) is a neglected virus with worldwide distribution of over 10 million people and is the cause of two main associated diseases Adult T cell Leukemia-Lymphoma (ATLL), and HTLV-1-associated Myelopathy/Tropical Spastic paraparesis (HAM/TSP). The IL-17 cytokine family plays a crucial role in the host immunity against HTLV-1 and the development of associated disease. A systematic review was conducted to analyze all research reporting on the levels or expression of the IL-17 HTLV-1 infection and associated diseases. METHODS: The literature search was conducted in electronic databases including PubMed/Medline and Web of Sciences until January 31st, 2024, followed by the PRISMA guidelines. RESULTS: Our search revealed 20 eligible articles to be included in our study. The total number of cases studied was 1420, of which 386 were carriers without any symptoms, and were 176 ATLL and 237 HAM/TSP. The IL-17 cytokine family production or mRNA expression was higher in HAM/TSP patients but showed a trend toward reduction in the case of ATLL. CONCLUSIONS: Our results showed that while The IL-17 cytokine family plays a significant role in the immunopathogenesis of disease and clinical status of patients with inflammatory disorders such as HAM/TSP, IL-17 production is diminished and the RORC/IL-17 signaling pathway is downregulated during ATLL. Our data suggest that boosting the RORC/IL-17 signaling pathway in ATLL and using anti-IL-17 agents in HAM/TSP and other HTLV-related inflammatory conditions might benefit patients and improve their outcomes.

High-sensitive sensory neurons exacerbate rosacea-like dermatitis in mice by activating γδ T cells directly.

Rosacea patients show facial hypersensitivity to stimulus factors (such as heat and capsaicin); however, the underlying mechanism of this hyperresponsiveness remains poorly defined. Here, we show capsaicin stimulation in mice induces exacerbated rosacea-like dermatitis but has no apparent effect on normal skin. Nociceptor ablation substantially reduces the hyperresponsiveness of rosacea-like dermatitis. Subsequently, we find that γδ T cells express Ramp1, the receptor of the neuropeptide CGRP, and are in close contact with these nociceptors in the skin. γδ T cells are significantly increased in rosacea skin lesions and can be further recruited and activated by neuron-secreted CGRP. Rosacea-like dermatitis is reduced in T cell receptor δ-deficient (Tcrd-/-) mice, and the nociceptor-mediated aggravation of rosacea-like dermatitis is also reduced in these mice. In vitro experiments show that CGRP induces IL17A secretion from γδ T cells by regulating inflammation-related and metabolism-related pathways. Finally, rimegepant, a CGRP receptor antagonist, shows efficacy in the treatment of rosacea-like dermatitis. In conclusion, our findings demonstrate a neuron-CGRP-γδT cell axis that contributes to the hyperresponsiveness of rosacea, thereby showing that targeting CGRP is a potentially effective therapeutic strategy for rosacea.

T-Cell Epitope Mapping of SARS-CoV-2 Reveals Coordinated IFN-γ Production and Clonal Expansion of T Cells Facilitates Recovery from COVID-19.

BACKGROUND: T-cell responses can be protective or detrimental during severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection; however, the underlying mechanism is poorly understood. METHODS: In this study, we screened 144 15-mer peptides spanning the SARS-CoV-2 spike, nucleocapsid (NP), M, ORF8, ORF10, and ORF3a proteins and 39 reported SARS-CoV-1 peptides in peripheral blood mononuclear cells (PBMCs) from nine laboratory-confirmed coronavirus disease 2019 (COVID-19) patients (five moderate and four severe cases) and nine healthy donors (HDs) collected before the COVID-19 pandemic. T-cell responses were monitored by IFN-γ and IL-17A production using ELISA, and the positive samples were sequenced for the T cell receptor (TCR) ß chain. The positive T-cell responses to individual SARS-CoV-2 peptides were validated by flow cytometry. RESULTS: COVID-19 patients with moderate disease produced more IFN-γ than HDs and patients with severe disease (moderate vs. HDs, p < 0.0001; moderate vs. severe, p < 0.0001) but less IL-17A than those with severe disease (p < 0.0001). A positive correlation was observed between IFN-γ production and T-cell clonal expansion in patients with moderate COVID-19 (r = 0.3370, p = 0.0214) but not in those with severe COVID-19 (r = -0.1700, p = 0.2480). Using flow cytometry, we identified that a conserved peptide of the M protein (Peptide-120, P120) was a dominant epitope recognized by CD8+ T cells in patients with moderate disease. CONCLUSION: Coordinated IFN-γ production and clonal expansion of SARS-CoV-2-specific T cells are associated with disease resolution in COVID-19. Our findings contribute to a better understanding of T-cell-mediated immunity in COVID-19 and may inform future strategies for managing and preventing severe outcomes of SARS-CoV-2 infection.

Activation of Antiviral Host Responses against Avian Influenza Virus and Remodeling of Gut Microbiota by rLAB Vector Expressing rIL-17A in Chickens.

Low-pathogenic avian influenza virus (LPAIV) remains the most common subtype of type-A influenza virus that causes moderate to severe infection in poultry with significant zoonotic and pandemic potential. Due to high mutability, increasing drug resistance, and limited vaccine availability, the conventional means to prevent intra- or interspecies transmission of AIV is highly challenging. As an alternative to control AIV infections, cytokine-based approaches to augment antiviral host defense have gained significant attention. However, the selective application of cytokines is critical since unregulated expression of cytokines, particularly proinflammatory ones, can cause substantial tissue damage during acute phases of immune responses. Moreover, depending on the type of cytokine and its impact on intestinal microbiota, outcomes of cytokine-gut microflora interaction can have a critical effect on overall host defense against AIV infections. Our recent study demonstrated some prominent roles of chicken IL-17A (ChIL-17A) in regulating antiviral host responses against AIV infection, however, in an in vitro model. For more detailed insights into ChIL-17A function, in the present study, we investigated whether ChIL-17A-meditated elevated antiviral host responses can translate into effective immune protection against AIV infection in an in vivo system. Moreover, considering the role of gut health in fostering innate or local host responses, we further studied the contributory relationships between gut microbiota and host immunity against AIV infection in chickens. For this, we employed a recombinant lactic acid-producing bacterial (LAB) vector, Lactococcus lactis, expressing ChIL-17A and analyzed the in vivo functionality in chickens against an LPAIV (A/H9N2) infection. Our study delineates that mucosal delivery of rL. lactis expressing ChIL-17A triggers proinflammatory signaling cascades and can drive a positive shift in phylum Firmicutes, along with a marked decline in phylum Actinobacteriota and Proteobacteria, favoring effective antiviral host responses against AIV infection in chickens. We propose that ChIL-17A-mediated selective expansion of beneficial gut microbiota might form a healthy microbial community that augments the effective immune protection against AIV infections in chickens.

Dysfunctional host cellular immune responses are associated with mortality in melioidosis.

Melioidosis is a tropical infection caused by the intracellular pathogen Burkholderia pseudomallei, an underreported and emerging global threat. As melioidosis-associated mortality is frequently high despite antibiotics, novel management strategies are critically needed. Therefore, we sought to determine whether functional changes in the host innate and adaptive immune responses are induced during acute melioidosis and are associated with outcome. Using a unique whole blood stimulation assay developed for use in resource-limited settings, we examined induced cellular functional and phenotypic changes in a cohort of patients with bacteremic melioidosis prospectively enrolled within 24 h of positive blood culture and followed for 28 days. Compared to healthy controls, melioidosis survivors generated an IL-17 response mediated by Th17 cells and terminally-differentiated effector memory CD8+ T cells (P < .05, both), persisting to 28 days after enrolment. Furthermore, melioidosis survivors developed polyfunctional cytokine production in CD8+ T cells (P < .01). Conversely, a reduction in CCR6+ CD4+ T cells was associated with higher mortality, even after adjustments for severity of illness (P = 0.004). Acute melioidosis was also associated with a profound acute impairment in monocyte function as stimulated cytokine responses were reduced in classical, intermediate and non-classical monocytes. Impaired monocyte cytokine function improved by 28-days after enrolment. These data suggest that IL-17 mediated cellular responses may be contributors to host defense during acute melioidosis, and that innate immune function may be impaired. These insights could provide novel targets for the development of therapies and vaccine targets in this frequently lethal disease.

Effect of IL-17A on the immune response to pulmonary tuberculosis induced by high- and low-virulence strains of Mycobacterium bovis.

Tuberculosis (TB) is an infectious, chronic, and progressive disease occurring globally. Human TB is caused mainly by Mycobacterium tuberculosis (M. tuberculosis), while the main causative agent of bovine TB is Mycobacterium bovis (M. bovis). The latter is one of the most important cattle pathogens and is considered the main cause of zoonotic TB worldwide. The mechanisms responsible for tissue damage (necrosis) during post-primary TB remain elusive. Recently, IL-17A was reported to be important for protection against M. tuberculosis infection, but it is also related to the production of an intense inflammatory response associated with necrosis. We used two M. bovis isolates with different levels of virulence and high IL-17A production to study this important cytokine's contrasting functions in a BALB/c mouse model of pulmonary TB. In the first part of the study, the gene expression kinetics and cellular sources of IL-17A were determined by real time PCR and immunohistochemistry respectively. Non-infected lungs showed low production of IL-17A, particularly by the bronchial epithelium, while lungs infected with the low-virulence 534 strain showed high IL-17A expression on Day 3 post-infection, followed by a decrease in expression in the early stage of the infection and another increase during late infection, on Day 60, when very low bacillary burdens were found. In contrast, infection with the highly virulent strain 04-303 induced a peak of IL-17A expression on Day 14 of infection, 1 week before extensive pulmonary necrosis was seen, being lymphocytes and macrophages the most important sources. In the second part of the study, the contribution of IL-17A to immune protection and pulmonary necrosis was evaluated by suppressing IL-17A via the administration of specific blocking antibodies. Infection with M. bovis strain 534 and treatment with IL-17A neutralizing antibodies did not affect mouse survival but produced a significant increase in bacillary load and a non-significant decrease in inflammatory infiltrate and granuloma area. In contrast, mice infected with the highly virulent 04-303 strain and treated with IL-17A blocking antibodies showed a significant decrease in survival, an increase in bacillary loads on Day 24 post-infection, and significantly more and earlier necrosis. Our results suggest that high expression of IL-17A is more related to protection than necrosis in a mouse model of pulmonary TB induced by M. bovis strains.

IL-17A/F double producing T cells, unstable Tregs and quiescent TRMs in clinically healed lesions are potential cellular candidates for recurrence of psoriasis.

Biological antibodies targeting key cytokines such as IL-17 and IL-23 have revolutionized psoriasis outcome. However, the recurrence remains an urgent challenge to be addressed. Currently, most of the descriptions of skin T-cell characteristics in psoriasis are derived from lesional and non-lesional skin, and their characteristics in resolved lesions (clinically healed lesions) remain vague. In order to further elucidate the cellular mechanism of recurrence, we performed single-cell sequencing and multiplexed immunohistochemical staining of T-cell subsets in autologous resolved lesion (RL), on-site recurrent psoriatic lesion (PL), and adjacent normal-appearing skin (NS) of psoriasis. By comparing with PL and NS tissues, we identified three potential cellular candidates for recurrence in clinically healed lesions: IL-17A/F double producing T cells, unstable Tregs and quiescent TRMs. Our results provide research clues for elucidating the immunological recurrence mechanism of psoriasis, and further work is needed to deepen our findings.

Prevalence of antiphospholipid autoantibodies associated with biologics treatment for psoriasis.

Psoriasis is a chronic inflammatory disease that sometimes necessitates therapeutic intervention with biologics. Autoantibody production during treatment with tumor necrosis factor (TNF) inhibitors is a recognized phenomenon, however, the production of autoantibodies associated with antiphospholipid syndrome (APS) has not been comprehensively evaluated in patients with psoriasis. This study was conducted to assess the prevalence of APS-associated autoantibodies in patients with psoriasis treated with different biologics and to investigate the potential associations between autoantibody production and clinical or serological parameters. Patients with psoriasis undergoing biologics treatments were enrolled in this study, and were categorized based on the type of biologics administered, TNF, interleukin (IL)-17, or IL-23 inhibitors. Clinical and serological data were collected and analyzed in conjunction with data on APS autoantibodies. TNF inhibitors were associated with a higher frequency of APS autoantibodies compared to IL-17 and IL-23 inhibitors. Notably, the presence of APS autoantibodies correlated with concurrent arthritis and higher disease severity at treatment initiation in patients treated with TNF inhibitors. Elevated Psoriasis Area and Severity Index scores and anti-nuclear antibody titers higher than × 320 were predictors of APS autoantibody production. Despite the higher autoantibody rates, clinical symptoms of APS were absent in these patients. This study provides the first comprehensive evidence of an increased frequency of APS autoantibodies associated with TNF inhibitor treatment in patients with psoriasis. The observed association between APS autoantibody positivity and TNF inhibitor treatment or clinical parameters suggests a potential immunomodulatory interplay between autoimmunity and inflammation in the pathogenesis of psoriasis.

Aryl hydrocarbon receptor (AhR)-mediated immune responses to degeneration of the retinal pigment epithelium.

Injuries to the retinal pigment epithelium (RPE) trigger immune responses, orchestrating interactions within the innate and adaptive immune systems in the outer retina and choroid. We previously reported that interleukin 17 (IL-17) is a pivotal signaling molecule originating from choroidal γδ T cells, exerting protective effects by mediating functional connections between the RPE and subretinal microglia. In this current study, we generated mice with aryl hydrocarbon receptor (AhR) knockout specifically in IL-17-producing cells. These animals had deficiency in IL-17 production from γδ T cells, and exhibited increased sensitivity to both acute and chronic insults targeting the RPE. These findings imply that IL-17 plays a crucial role as a signaling cytokine in preserving the homeostasis of the outer retina and choroid.

An intestinal TH17 cell-derived subset can initiate cancer.

Approximately 25% of cancers are preceded by chronic inflammation that occurs at the site of tumor development. However, whether this multifactorial oncogenic process, which commonly occurs in the intestines, can be initiated by a specific immune cell population is unclear. Here, we show that an intestinal T cell subset, derived from interleukin-17 (IL-17)-producing helper T (TH17) cells, induces the spontaneous transformation of the intestinal epithelium. This subset produces inflammatory cytokines, and its tumorigenic potential is not dependent on IL-17 production but on the transcription factors KLF6 and T-BET and interferon-γ. The development of this cell type is inhibited by transforming growth factor-ß1 (TGFß1) produced by intestinal epithelial cells. TGFß signaling acts on the pretumorigenic TH17 cell subset, preventing its progression to the tumorigenic stage by inhibiting KLF6-dependent T-BET expression. This study therefore identifies an intestinal T cell subset initiating cancer.

Combinatorial actions of IL-22 and IL-17 drive optimal immunity to oral candidiasis through SPRRs.

Oropharyngeal candidiasis (OPC) is the most common human fungal infection, arising typically from T cell immune impairments. IL-17 and IL-22 contribute individually to OPC responses, but here we demonstrate that the combined actions of both cytokines are essential for resistance to OPC. Mice lacking IL-17RA and IL-22RA1 exhibited high fungal loads in esophagus- and intestinal tract, severe weight loss, and symptoms of colitis. Ultimately, mice succumbed to infection. Dual loss of IL-17RA and IL-22RA impaired expression of small proline rich proteins (SPRRs), a class of antimicrobial effectors not previously linked to fungal immunity. Sprr2a1 exhibited direct candidacidal activity in vitro, and Sprr1-3a-/- mice were susceptible to OPC. Thus, cooperative actions of Type 17 cytokines mediate oral mucosal anti-Candida defenses and reveal a role for SPRRs.

Targeting cytokines in psoriatic arthritis.

Psoriatic arthritis (PsA) is part of the psoriatic disease spectrum and is characterized by a chronic inflammatory process that affects entheses, tendons and joints. Cytokines produced by immune and non-immune cells play a central role in the pathogenesis of PsA by orchestrating key aspects of the inflammatory response. Pro-inflammatory cytokines such as TNF, IL-23 and IL-17 have been shown to regulate the initiation and progression of PsA, ultimately leading to the destruction of the architecture of the local tissues such as soft tissue, cartilage and bone. The important role of cytokines in PsA has been underscored by the clinical success of antibodies that neutralize their function. In addition to biologic agents targeting individual pro-inflammatory cytokines, signaling inhibitors that block multiple cytokines simultaneously such as JAK inhibitors have been approved for PsA therapy. In this review, we will focus on our current understanding of the role of cytokines in the disease process of PsA and discuss potential new treatment options based on modulation of cytokine function.

Risk of neutropenia in psoriasis patients prescribed anti-IL-23 antibody in comparison with anti-IL-17 antibody or adalimumab based on real-world data from the MID-NET® in Japan.

BACKGROUND: To evaluate the risk of neutropenia during treatment with anti-IL-23 antibodies in patients with psoriasis. METHOD: We conducted an observational study with cohort design using MID-NET® in Japan. We identified patients with psoriasis who were newly prescribed anti-IL-23 antibodies, anti-IL-17-antibodies, adalimumab, or apremilast between January 1, 2009, and March 31, 2021. We estimated the adjusted hazard ratio (aHR) of anti-IL-23 antibodies compared to that of anti-IL-17 antibodies, adalimumab, or apremilast, for the risk of grade 2 (neutrophil count < 1,500/µL) or grade 3 (neutrophil count < 1,000/µL) neutropenia. RESULTS: Overall, 287 patients on anti-IL-23 antibodies, 189 patients on anti-IL-17 antibodies, 293 patients on adalimumab, and 540 patients on apremilast were included. Compared with anti-IL-17 antibodies, the aHR (95% confidence interval (CI)) of anti-IL-23 antibodies was 0.83 (0.27-2.51) for grade 2 and 0.40 (0.02-7.60) for grade 3 neutropenia; that when compared with adalimumab was 0.76 (0.28-2.06) for grade 2 but was not calculated for grade 3 as no cases were found; and that compared with apremilast was 3.88 (0.62-24.48) for grade 2 and 0.43 (0.02-11.63) for grade 3 neutropenia. CONCLUSION: No clear increase in the risk of neutropenia with anti-IL-23 antibodies was observed.

Yeast and filamentous Candida auris stimulate distinct immune responses in the skin.

Candida auris, an emerging multidrug-resistant fungal pathogen, predominately colonizes the human skin long term leading to subsequent life-threatening invasive infections. Fungal morphology is believed to play a critical role in modulating mucocutaneous antifungal immunity. In this study, we used an intradermal mouse model of C. auris infection to examine fungal colonization and the associated innate and adaptive immune response to yeast and filamentous C. auris strains. Our results indicate that mice infected with a filamentous C. auris had significantly decreased fungal load compared to mice infected with the yeast form. Mice infected with yeast and filamentous forms of C. auris stimulated distinct innate immune responses. Phagocytic cells (CD11b+Ly6G+ neutrophils, CD11b+Ly6Chi inflammatory monocytes, and CD11b+MHCII+CD64+ macrophages) were differentially recruited to mouse skin tissue infected with yeast and filamentous C. auris. The percentage and absolute number of interleukin 17 (IL-17) producing innate lymphoid cells, TCRγδ+, and CD4+ T cells in the skin tissue of mice infected with filamentous C. auris were significantly increased compared to the wild-type of yeast strain. Furthermore, complementation of filamentous mutant strain of C. auris (Δelm1 + ELM1) strain exhibited wild-type yeast morphology in vivo and induced comparable level of skin immune responses similar to mice infected with yeast strain. Collectively, our findings indicate that yeast and filamentous C. auris induce distinct local immune responses in the skin. The decreased fungal load observed in mouse skin infected with filamentous C. auris is associated with a potent IL-17 immune response induced by this morphotype.IMPORTANCECandida auris is a globally emerging fungal pathogen that transmits among individuals in hospitals and nursing home residents. Unlike other Candida species, C. auris predominantly colonizes and persists in skin tissue resulting in outbreaks of systemic infections. Understanding the factors that regulate C. auris skin colonization and host immune response is critical to develop novel preventive and therapeutic approaches against this emerging pathogen. We identified that yeast and filamentous forms of C. auris induce distinct skin immune responses in the skin. These findings may help explain the differential colonization and persistence of C. auris morphotypes in skin tissue. Understanding the skin immune responses induced by yeast and filamentous C. auris is important to develop novel vaccine strategies to combat this emerging fungal pathogen.