A repeating fast radio burst source localized to a nearby spiral galaxy.

Fast radio bursts (FRBs) are brief, bright, extragalactic radio flashes1,2. Their physical origin remains unknown, but dozens of possible models have been postulated3. Some FRB sources exhibit repeat bursts4-7. Although over a hundred FRB sources have been discovered8, only four have been localized and associated with a host galaxy9-12, and just one of these four is known to emit repeating FRBs9. The properties of the host galaxies, and the local environments of FRBs, could provide important clues about their physical origins. The first known repeating FRB, however, was localized to a low-metallicity, irregular dwarf galaxy, and the apparently non-repeating sources were localized to higher-metallicity, massive elliptical or star-forming galaxies, suggesting that perhaps the repeating and apparently non-repeating sources could have distinct physical origins. Here we report the precise localization of a second repeating FRB source6, FRB 180916.J0158+65, to a star-forming region in a nearby (redshift 0.0337 ± 0.0002) massive spiral galaxy, whose properties and proximity distinguish it from all known hosts. The lack of both a comparably luminous persistent radio counterpart and a high Faraday rotation measure6 further distinguish the local environment of FRB 180916.J0158+65 from that of the single previously localized repeating FRB source, FRB 121102. This suggests that repeating FRBs may have a wide range of luminosities, and originate from diverse host galaxies and local environments.

A dairy-based, protein-rich breakfast enhances satiety and cognitive concentration before lunch in overweight to obese young females: A randomized controlled crossover study.

The purpose of this study was to investigate if consumption of a high-protein, low-carbohydrate breakfast (PRO) leads to a lower subsequent ad libitum energy intake at lunch and the rest of the day compared with ingestion of an isocaloric low-protein, high-carbohydrate breakfast (CHO) or no breakfast (CON). The study was designed as a randomized controlled 3-period crossover study. Thirty young (18-30 yr) females with overweight to obesity (body mass index >25 kg/m2) in random order completed 3 separate experimental days where they consumed either a PRO, CHO, or CON breakfast test meal followed by an ad libitum lunch meal 3 h after breakfast. Participants were allocated to a sequence group by their inclusion number. The PRO and CHO breakfasts were matched in dietary fiber and fat content. Energy intake at lunch was calculated and dietary records were obtained for the rest of the day to calculate the total daily energy intake and macronutrient intake. Ratings of appetite sensations between meals and palatability of the test meals were assessed using visual analog scale sheets in intervals ranging from 10 to 30 min. In addition, blood samples were obtained at multiple time points separated by 10 to 60 min intervals between breakfast and lunch and were analyzed for appetite-regulating gut hormones, insulin, and glucose. Finally, performance in a cognitive concentration test was tested 150 min after breakfast. Compared with CHO and CON, the area under the curves for satiety, fullness, and satisfaction in the 3 h after breakfast were significantly higher after PRO, whereas the areas under the curve for hunger, desire to eat, and prospective eating were significantly lower after PRO. The appetite-regulating gut hormones cholecystokinin, glucagon-like peptide-1, and ghrelin in the hours after breakfast, energy intake during the ad libitum lunch meal, and the total daily energy intake did not differ significantly between PRO, CHO, and CON. However, the cognitive concentration test score was 3.5 percentage points higher for PRO, but not CHO, versus CON. A dairy-based high-protein, low-carbohydrate breakfast increased satiety sensation in the hours after breakfast but did not reduce total daily energy intake compared with an isocaloric low-protein, high-carbohydrate breakfast or omitting breakfast. However, performance in a cognitive concentration test before lunch was enhanced after the high-protein, low-carbohydrate breakfast, but not the low-protein, high-carbohydrate breakfast, compared with omitting breakfast.

Application of 89Zr-DFO*-immuno-PET to assess improved target engagement of a bispecific anti-amyloid-ß monoclonal antibody.

PURPOSE: The recent conditional FDA approval of Aducanumab (Adu) for treating Alzheimer's disease (AD) and the continued discussions around that decision have increased interest in immunotherapy for AD and other brain diseases. Reliable techniques for brain imaging of antibodies may guide decision-making in the future but needs further development. In this study, we used 89Zr-immuno-PET to evaluate the targeting and distribution of a bispecific brain-shuttle IgG based on Adu with transferrin receptor protein-1 (TfR1) shuttling mechanism, mAbAdu-scFab8D3, designated Adu-8D3, as a candidate theranostic for AD. We also validated the 89Zr-immuno-PET platform as an enabling technology for developing new antibody-based theranostics for brain disorders. METHODS: Adu, Adu-8D3, and the non-binding control construct B12-8D3 were modified with DFO*-NCS and radiolabeled with 89Zr. APP/PS1 mice were injected with 89Zr-labeled mAbs and imaged on days 3 and 7 by positron emission tomography (PET). Ex vivo biodistribution was performed on day 7, and ex vivo autoradiography and immunofluorescence staining were done on brain tissue to validate the PET imaging results and target engagement with amyloid-ß plaques. Additionally, [89Zr]Zr-DFO*-Adu-8D3 was evaluated in 3, 7, and 10-month-old APP/PS1 mice to test its potential in early stage disease. RESULTS: A 7-fold higher brain uptake was observed for [89Zr]Zr-DFO*-Adu-8D3 compared to [89Zr]Zr-DFO*-Adu and a 2.7-fold higher uptake compared to [89Zr]Zr-DFO*-B12-8D3 on day 7. Autoradiography and immunofluorescence of [89Zr]Zr-DFO*-Adu-8D3 showed co-localization with amyloid plaques, which was not the case with the Adu and B12-8D3 conjugates. [89Zr]Zr-DFO*-Adu-8D3 was able to detect low plaque load in 3-month-old APP/PS1 mice. CONCLUSION: 89Zr-DFO*-immuno-PET revealed high and specific uptake of the bispecific Adu-8D3 in the brain and can be used for the early detection of Aß plaque pathology. Here, we demonstrate that 89Zr-DFO*-immuno-PET can be used to visualize and quantify brain uptake of mAbs and contribute to the evaluation of biological therapeutics for brain diseases.

Visualization of Local Magnetic Moments Emerging from Impurities in Hund's Metal States of FeSe.

Understanding the origin of the magnetism of high temperature superconductors is crucial for establishing their unconventional pairing mechanism. Recently, theory predicts that FeSe is close to a magnetic quantum critical point, and thus weak perturbations such as impurities could induce local magnetic moments. To elucidate such quantum instability, we have employed scanning tunneling microscopy and spectroscopy. In particular, we have grown FeSe film on superconducting Pb(111) using molecular beam epitaxy and investigated magnetic excitation caused by impurities in the proximity-induced superconducting gap of FeSe. Our study provides deep insight into the origin of the magnetic ordering of FeSe by showing the way local magnetic moments develop in response to impurities near the magnetic quantum critical point.

Validity and reliability of State-Trait Anxiety Inventory in Danish women aged 45 years and older with abnormal cervical screening results.

BACKGROUND: State Trait Anxiety Inventory (STAI) scale was developed in the 1980's and has been widely used both in clinical settings and in research. However the Danish version of STAI has not been validated. The aim of this study was to assess the validity and reliability of STAI - state anxiety scale in Danish women aged 45 years and older with abnormal cervical cancer screening results. METHODS: Women ≥45 years referred with an abnormal cervical cytology and healthy volunteers (n = 12) underwent cognitive interview after completing STAI. Further, STAI was sent out in an electronic questionnaire to women (n = 109) seen at the gynecological department with abnormal cervical cancer screening test during 2018. Validity and reliability of STAI was evaluated according to the Consensus-based Standards for the selection of health Measurement Instruments (COSMIN) checklist by examining internal consistency, test-retest reliability, measurement error, floor and ceiling, construct validity and content validity. RESULTS: In the cognitive interviews the content validity was evaluated to be very good. The internal consistency of the scale was excellent with Cronbach's α = 0.93. Test-retest reliability was good with an intra-class correlation coefficient of 0.80 and the systematic difference between test-retest results was negligible. The construct validity was good. CONCLUSION: To our best knowledge, this is the first validation study of the Danish translation of STAI-state anxiety scale. This version of STAI demonstrates an acceptable reliability and validity when used in a gynecological setting.

Imaging orbital-selective quasiparticles in the Hund's metal state of FeSe.

Strong electronic correlations, emerging from the parent Mott insulator phase, are key to copper-based high-temperature superconductivity. By contrast, the parent phase of an iron-based high-temperature superconductor is never a correlated insulator. However, this distinction may be deceptive because Fe has five actived d orbitals while Cu has only one. In theory, such orbital multiplicity can generate a Hund's metal state, in which alignment of the Fe spins suppresses inter-orbital fluctuations, producing orbitally selective strong correlations. The spectral weights Zm of quasiparticles associated with different Fe orbitals m should then be radically different. Here we use quasiparticle scattering interference resolved by orbital content to explore these predictions in FeSe. Signatures of strong, orbitally selective differences of quasiparticle Zm appear on all detectable bands over a wide energy range. Further, the quasiparticle interference amplitudes reveal that [Formula: see text], consistent with earlier orbital-selective Cooper pairing studies. Thus, orbital-selective strong correlations dominate the parent state of iron-based high-temperature superconductivity in FeSe.

Knight Shift and Leading Superconducting Instability from Spin Fluctuations in Sr_{2}RuO_{4}.

Recent nuclear magnetic resonance studies [A. Pustogow et al., Nature 574, 72 (2019)] have challenged the prevalent chiral triplet pairing scenario proposed for Sr_{2}RuO_{4}. To provide guidance from microscopic theory as to which other pair states might be compatible with the new data, we perform a detailed theoretical study of spin fluctuation mediated pairing for this compound. We map out the phase diagram as a function of spin-orbit coupling, interaction parameters, and band structure properties over physically reasonable ranges, comparing when possible with photoemission and inelastic neutron scattering data information. We find that even-parity pseudospin singlet solutions dominate large regions of the phase diagram, but in certain regimes spin-orbit coupling favors a near-nodal odd-parity triplet superconducting state, which is either helical or chiral depending on the proximity of the γ band to the van Hove points. A surprising near degeneracy of the nodal s^{'} and d_{x^{2}-y^{2}} wave solutions leads to the possibility of a near-nodal time-reversal symmetry broken s^{'}+id_{x^{2}-y^{2}} pair state. Predictions for the temperature dependence of the Knight shift for fields in and out of plane are presented for all states.

Cladosporium species in indoor environments.

As part of a worldwide survey of the indoor mycobiota about 520 new Cladosporium isolates from indoor environments mainly collected in China, Europe, New Zealand, North America and South Africa were investigated by using a polyphasic approach to determine their species identity. All Cladosporium species occurring in indoor environments are fully described and illustrated. Fourty-six Cladosporium species are treated of which 16 species are introduced as new. A key for the most common Cladosporium species isolated from indoor environments is provided. Cladosporium halotolerans proved to be the most frequently isolated Cladosporium species indoors.

Increased glucose-stimulated FGF21 response to oral glucose in obese nondiabetic subjects after Roux-en-Y gastric bypass.

OBJECTIVE: The positive metabolic outcome of Roux-en-Y gastric bypass (RYGB) surgery may involve fibroblast growth factor 21 (FGF21), in both the fasting state and postprandially. We measured the fasting levels of FGF21 before and after bariatric surgery as well as the postprandial FGF21 responses after a glucose load and after a mixed meal. DESIGN: Observational intervention trial. PATIENTS AND MEASUREMENTS: Eight obese, nondiabetic patients underwent RYGB. Plasma FGF21 was measured both before and after surgery on three different days during oral glucose loads (25 g or 50 g glucose) or a mixed meal. Blood samples were taken right before the meal and at 15-min intervals until 90 min and at 150 min and 210 min relative to the start of the meal. RESULTS: Overall, fasting plasma FGF21 did not change significantly before and after surgery (262 ± 71 vs 411 ± 119 pg/ml), but for three subjects, fasting plasma FGF21 increased significantly after surgery. Furthermore, FGF21 levels increased significantly at t = 90 and t = 150 min in response to 50 g glucose, but not after a mixed meal. CONCLUSIONS: In conclusion, the observed increase in postprandial plasma FGF21 in response to glucose and the lack of FGF21 response to a mixed meal may have important implications for the physiologic role of FGF21. The increase in postprandial FGF21 in response to glucose in the early postoperative period may contribute to the metabolic improvements observed after gastric bypass.

Potentially harmful secondary metabolites produced by indoor Chaetomium species on artificially and naturally contaminated building materials.

The presence of the fungal genus Chaetomium and its secondary metabolites in indoor environments is suspected to have a negative impact on human health and well-being. About 200 metabolites have been currently described from Chaetomium spp., but only the bioactive compound group, chaetoglobosins, have been screened for and thus detected in buildings. In this study, we used a liquid chromatography high-resolution mass spectrometry approach to screen both artificially and naturally infected building materials for all the Chaetomium metabolites described in the literature. Pure agar cultures were also investigated to establish differences between metabolite production in vitro and on building materials as well as in comparison with non-indoor reference strains. On building materials, six different chaetoglobosins were detected in total concentrations of up to 950 mg/m2 from Chaetomium globosum along with three different chaetoviridins/chaetomugilins in concentrations up to 200 mg/m2 . Indoor Chaetomium spp. preferred wood-based materials over gypsum, both in terms of growth rate and metabolite production. Cochliodones were detected for the first time on all building materials infected by both C. globosum and Chaetomium elatum and are thus candidates as Chaetomium biomarkers. No sterigmatocystin was produced by Chaetomium spp. from indoor environment.

Pre-contamination of new gypsum wallboard with potentially harmful fungal species.

Gypsum wallboard is a popular building material, but is also very frequently overgrown by Stachybotrys chartarum after severe and/or undetected water damage. The purpose of this study was to determine whether Stachybotrys and other fungi frequently isolated from wet gypsum wallboard are already present in the panels directly from the factory. Surface-disinfected gypsum disks were wetted with sterile water, sealed, and incubated for 70 days. The results showed that Neosartorya hiratsukae (≡ Aspergillus hiratsukae) was the most dominant fungus on the gypsum wallboard followed by Chaetomium globosum and Stachybotrys chartarum. Our results suggest that these three fungal species are already embedded in the materials, presumably in the paper/carton layer surrounding the gypsum core, before the panels reach the retailers/building site.

Diversity and taxonomy of Chaetomium and chaetomium-like fungi from indoor environments.

During a study of indoor fungi, 145 isolates belonging to Chaetomiaceae were cultured from air, swab and dust samples from 19 countries. Based on the phylogenetic analyses of DNA-directed RNA polymerase II second largest subunit (rpb2), ß-tubulin (tub2), ITS and 28S large subunit (LSU) nrDNA sequences, together with morphological comparisons with related genera and species, 30 indoor taxa are recognised, of which 22 represent known species, seven are described as new, and one remains to be identified to species level. In our collection, 69 % of the indoor isolates with six species cluster with members of the Chaetomium globosum species complex, representing Chaetomium sensu stricto. The other indoor species fall into nine lineages that are separated from each other with several known chaetomiaceous genera occurring among them. No generic names are available for five of those lineages, and the following new genera are introduced here: Amesia with three indoor species, Arcopilus with one indoor species, Collariella with four indoor species, Dichotomopilus with seven indoor species and Ovatospora with two indoor species. The generic concept of Botryotrichum is expanded to include Emilmuelleria and the chaetomium-like species B. muromum (= Ch. murorum) in which two indoor species are included. The generic concept of Subramaniula is expanded to include several chaetomium-like taxa as well as one indoor species. Humicola is recognised as a distinct genus including two indoor taxa. According to this study, Ch. globosum is the most abundant Chaetomiaceae indoor species (74/145), followed by Ch. cochliodes (17/145), Ch. elatum (6/145) and B. piluliferum (5/145). The morphological diversity of indoor Chaetomiaceae as well as the morphological characteristics of the new genera are described and illustrated. This taxonomic study redefines the generic concept of Chaetomium and provides new insight into the phylogenetic relationships among different genera within Chaetomiaceae.

Human Atopic Dermatitis Skin-derived T Cells can Induce a Reaction in Mouse Keratinocytes in vivo.

In atopic dermatitis (AD), the inflammatory response between skin-infiltrating T cells and keratinocytes is fundamental to the development of chronic lesional eczema. The aim of this study was to investigate whether skin-derived T cells from AD patients could induce an inflammatory response in mice through keratinocyte activation and consequently cause the development of eczematous lesions. Punch biopsies of the lesional skin from AD patients were used to establish skin-derived T cell cultures, which were transferred to NOD.Cg-Prkd(scid) Il2rg(tm1Sug) /JicTac (NOG) mice. We found that the subcutaneous injection of the human AD skin-derived T cells resulted in the migration of the human T cells from subcutis to the papillary dermis followed by the development of erythema and oedema in the mouse skin. Furthermore, the human T cells induced a transient proliferative response in the mouse keratinocytes shown as increased numbers of Ki-67(+) keratinocytes and increased epidermal thickness. Out of six established AD skin-derived T cell cultures, two were superior at inducing a skin reaction in the mice, and these cultures were found to contain >10% CCR10(+) T cells compared to <2% for the other cultures. In comparison, blood-derived in vitro-differentiated Th2 cells only induced a weak response in a few of the mice. Thus, we conclude that human AD skin-derived T cells can induce a reaction in the mouse skin through the induction of a proliferative response in the mouse keratinocytes.

The Vitamin D Analogue Calcipotriol Reduces the Frequency of CD8+ IL-17+ T Cells in Psoriasis Lesions.

The vitamin D analogue calcipotriol is an immunomodulatory drug widely used to treat psoriasis; however, how calcipotriol affects the immune cells in psoriasis lesions is not fully understood. The aim of this study was to investigate the effect of calcipotriol on the frequency of CD4(+) and CD8(+) T cells and innate lymphoid cells (ILC) and their production of IL-17A, IFN-γ and IL-22 in psoriasis lesions in patients with chronic plaque psoriasis. Eighteen patients with psoriasis were included, and two similar psoriasis lesions were chosen for each patient. One lesion was treated with calcipotriol (50 µg/g) and the other with vehicle twice a day for 14 days. The clinical effect was measured by degree of erythema, scaling and induration in each lesion (SUM score). Skin biopsies were collected for histological and immunohistochemical analyses. Skin-derived cells were isolated and analysed by flow cytometry. After 14 days of treatment with calcipotriol, a significant clinical and histological effect was seen; however, we found no differences in the frequency of CD4(+) and CD8(+) T cells or ILC between calcipotriol- and vehicle-treated skin. The main finding was a significant decrease in CD8(+) IL-17(+) T cells in skin-derived cells from calcipotriol-treated skin, which was further supported by the absence of CD8(+) IL-17(+) T cells in immunohistochemical staining of calcipotriol-treated skin. No changes in the frequency of IL-22(+) or IFN-γ(+) cells were observed. Our findings show that the vitamin D analogue calcipotriol reduces the frequency of CD8(+) IL-17(+) T cells in psoriasis lesions concomitant with clinical improvement.

Interpretation of scanning tunneling quasiparticle interference and impurity states in cuprates.

We apply a recently developed method combining first principles based Wannier functions with solutions to the Bogoliubov-de Gennes equations to the problem of interpreting STM data in cuprate superconductors. We show that the observed images of Zn on the surface of Bi_{2}Sr_{2}CaCu_{2}O_{8} can only be understood by accounting for the tails of the Cu Wannier functions, which include significant weight on apical O sites in neighboring unit cells. This calculation thus puts earlier crude "filter" theories on a microscopic foundation and solves a long-standing puzzle. We then study quasiparticle interference phenomena induced by out-of-plane weak potential scatterers, and show how patterns long observed in cuprates can be understood in terms of the interference of Wannier functions above the surface. Our results show excellent agreement with experiment and enable a better understanding of novel phenomena in the cuprates via STM imaging.

Non-participation in breast cancer screening for women with chronic diseases and multimorbidity: a population-based cohort study.

BACKGROUND: Chronic diseases and multimorbidity are common in western countries and associated with increased breast cancer mortality. This study aims to investigate non-participation in breast cancer screening among women with chronic diseases and multimorbidity and the role of time in this association. METHOD: This population-based cohort study used regional and national registries. Women who were invited to the first breast cancer screening round in the Central Denmark Region in 2008-09 were included (n = 149,234). Selected chronic diseases and multimorbidity were assessed up to 10 years before the screening date. Prevalence ratios (PR) were used as an association measure. RESULTS: The results indicated that women with at least one chronic condition were significantly more likely not to participate in breast cancer screening. In adjusted analysis, a significantly higher likelihood of non-participation was found for women with cancer (PR = 1.50, 95% CI: 1.40-1.60), mental illness (PR = 1.51, 95% CI: 1.42-1.60), chronic obstructive pulmonary disease (PR = 1.51, 95% CI: 1.42-1.62), neurological disorders (PR = 1.24, 95% CI: 1.12-1.37) and kidney disease (PR = 1.70, 95% CI 1.49-1.94), whereas women with chronic bowel disease (PR = 0.75, 95% CI 0.65-0.88) were more likely to participate than women without these disease. Multimorbidity was associated with increased non-participation likelihood. E.g. having 3 or more diseases was associated with 58% increased non-participation likelihood (95% CI: 27-96%). Higher non-participation was also observed for women with severe multimorbidity (PR = 1.53, 95% CI: 1.23-1.90) and mental-physical multimorbidity (PR = 1.54, 95% CI: 1.36-1.75). CONCLUSION: In conclusion, we found a strong association between non-participation in breast cancer screening for some chronic diseases and for multimorbidity. The highest propensity not to participate was observed for women with hospital contacts related to the chronic disease in the period closest to the screening date.

Design, implementation, and evaluation of a mobile application for patient empowerment and management of long-term follow-up after childhood cancer.

In Germany, about 1,800 new cases of childhood cancer are diagnosed every year. The chances of survival have increased significantly over the last 40 years due to the continuous improvement of treatment strategies. The number of childhood cancer survivors in Germany thus ranges around 30,000 nowadays. But their treatment with surgery, chemotherapy, and radiation has certain side-effects. In addition to the acute effects during the treatment phase, the disease- and treatment-related late effects can occur even decades after the end of therapy. These late effects draw attention as the survival rate constantly increases. Two-thirds of the former patients retain long-term consequences, nearly a fifth with a resulting diminished quality of life. Early detection of these late effects can help to reduce or even to prevent serious health damage. Therefore, the study group LESS supplies long-term follow-up recommendations for former patients. The project described in this paper was to design and implement a mobile application to increase the compliance for this aftercare program. This application provides information about the patient's individual aftercare plan and supports appointment management as well as a reminding functionality. A prototype for former osteosarcoma patients was tested and evaluated in two university hospitals. First results show the application's very high potential for patient empowerment.

Increased fibroblast growth factor 21 expression in high-fat diet-sensitive non-human primates (Macaca mulatta).

OBJECTIVE: Fibroblast growth factor 21 (FGF21) is a metabolic regulator of glucose and lipid metabolism. The physiological role of FGF21 is not yet fully elucidated, however, administration of FGF21 lowers blood glucose in diabetic animals. Moreover, increased levels of FGF21 are found in obese and diabetic rodents and humans compared with lean/non-diabetic controls. METHODS: Adult male rhesus macaque monkeys were chronically maintained on a high-fat diet (HFD) or a standard diet (control, CTR). Plasma levels of FGF21, triglycerides and cholesterol were measured and body weight was record. Glucose-stimulated insulin secretion (GSIS) and glucose clearance was determined during an intravenous glucose tolerance test. Furthermore, expression of FGF21 and its receptors were determined in liver, pancreas, three white adipose tissues (WATs) and two skeletal muscles. RESULTS: A cohort of the high-fat fed monkeys responded to the HFD with increasing body weight, plasma lipids, total cholesterol, GSIS and decreased glucose tolerance. These monkeys were termed HFD sensitive. Another cohort of monkeys did not become obese and maintained normal insulin sensitivity. These animals were defined as HFD resistant. Plasma FGF21 levels were significantly increased in all HFD fed monkeys compared with the CTR group. The HFD-sensitive monkeys showed a significant increase in FGF21 mRNA expression in all examined tissues compared with CTR, whereas FGF21 expression in the HFD-resistant group was only increased in the liver, pancreas and the retroperitoneal WAT. In the WAT, the co-receptor ß-klotho was downregulated in the HFD-sensitive monkeys compared with the HFD-resistant group. CONCLUSION: This study demonstrates that HFD changes FGF21 and FGF21 receptor expression in a tissue-specific manner in rhesus monkeys; differential regulation is moreover observed between HFD-sensitive and -resistant monkeys. Monkeys that maintain normal levels of the FGF21 co-receptor ß-klotho in the WAT on HFD were protected toward development of dyslipidemia and hyperglycemia.

Increased number and frequency of group 3 innate lymphoid cells in nonlesional psoriatic skin.

BACKGROUND: Psoriasis is a common immune-mediated inflammatory disease that affects the skin and joints. The interleukin (IL)-23/IL-17A axis and IL-22 play key roles in the pathogenesis of psoriasis. IL-23-responsive innate lymphoid cells (ILCs) with a high capacity to produce IL-17 and/or IL-22 have recently been identified and associated with inflammatory bowel diseases. The occurrence and role of ILCs in human skin are poorly understood. OBJECTIVES: To describe the prevalence of the different ILC subpopulations in skin from healthy controls and patients with psoriasis or allergy to nickel. METHODS: Skin biopsies were taken from healthy skin, nonlesional and lesional psoriatic skin, and nickel- and petrolatum-exposed skin from patients with contact allergy to nickel, and lymphocytes were isolated. The cells were stained and characterized by flow cytometry. Cytokine and ligand mRNA expression were measured by quantitative polymerase chain reaction. RESULTS: We found that members of the three groups of ILCs were present in human skin. Remarkably, the number and frequency of RORγt(+) CD56(+) ILC3s, which are known to produce IL-22, were elevated in both nonlesional and lesional skin from patients with psoriasis compared with healthy skin and skin from patients with contact allergy to nickel. Furthermore, skin ILCs expressed high levels of the natural killer receptor NKG2D. NKG2D binds to stress-induced ligands, including major histocompatibility complex class I-related chain A, which we found to be strongly upregulated in lesional skin from patients with psoriasis. CONCLUSION: These results show that ILCs are present in human skin and indicate that RORγt(+) CD56(+) ILC3 may be involved in the pathogenesis of psoriasis.