In vitro 3D full-thickness reconstituted human skin has high physiological relevance due to the presence of differentiation features often lacking in 2D cell cultures. Here, we present a protocol to reconstruct a 3D skin model using human fibroblasts, keratinocytes, and rat-tail collagen I. We describe steps for cell expansion, the casting of cellular and acellular layers, seeding keratinocytes, the air lifting of culture, and incubation.
View Article and Find Full Text PDFIn 2020-2021, a "mysterious illness" struck Senegalese fishermen, causing severe acute dermatitis in over one thousand individuals following exposure through drift-net fishing activity. Here, by performing deep analysis of the environmental samples we reveal the presence of the marine dinoflagellate Vulcanodinium rugosum and its associated cyclic imine toxins. Specifically, we show that the toxin PortimineA, strongly enriched in environmental samples, impedes ribosome function in human keratinocytes, which subsequently activates the stress kinases ZAKα and P38 and promotes the nucleation of the human NLRP1 inflammasome, leading to the release of IL-1β/IL-18 pro-inflammatory cytokines and cell death.
View Article and Find Full Text PDFBackground: Loss-of-function FLG mutation (FLGmut) carriers are at an increased risk of developing atopic dermatitis (AD), characterized by earlier onset and more severe disease. AD is driven by a complex interplay between skin barrier function, T2 and T2-dominant immune dysregulation, and dysbiosis. Results from the Short-Term Topical Application for Prevention of Atopic Dermatitis study suggest 2 early initiating AD pathogenetic pathways: an FLGmut-related skin barrier deficiency pathway and an immune function-related inflammatory pathway.
View Article and Find Full Text PDFNPJ Biofilms Microbiomes
January 2025
Honey bee viruses are serious pathogens that can cause poor colony health and productivity. We analyzed a multi-year longitudinal dataset of abundances of nine honey bee viruses (deformed wing virus A, deformed wing virus B, black queen cell virus, sacbrood virus, Lake Sinai virus, Kashmir bee virus, acute bee paralysis virus, chronic bee paralysis virus, and Israeli acute paralysis virus) in colonies located across Canada to describe broad trends in virus intensity and occurrence among regions and years. We also tested climatic variables (temperature, wind speed, and precipitation) as predictors in an effort to understand possible drivers underlying seasonal patterns in viral prevalence.
View Article and Find Full Text PDFSolar UVB light causes damage to the outermost layer of skin. This insult induces rapid local responses, such as dermal inflammation, keratinocyte cell death, and epidermal thickening, all of which have traditionally been associated with DNA damage response signaling. Another stress response that is activated by UVB light is the ribotoxic stress response (RSR), which depends on the ribosome-associated mitogen-activated protein 3 kinases (MAP3K) ZAKα and culminates in p38 and JNK activation.
View Article and Find Full Text PDFRecent declines in the health of honey bee colonies used for crop pollination pose a considerable threat to global food security. Foraging by honey bee workers represents the primary route of exposure to a plethora of toxins and pathogens known to affect bee health, but it remains unclear how foraging preferences impact colony-level patterns of stressor exposure. Resolving this knowledge gap is crucial for enhancing the health of honey bees and the agricultural systems that rely on them for pollination.
View Article and Find Full Text PDFHighbush blueberry pollination depends on managed honey bees (Apis mellifera) L. for adequate fruit sets; however, beekeepers have raised concerns about the poor health of colonies after pollinating this crop. Postulated causes include agrochemical exposure, nutritional deficits, and interactions with parasites and pathogens, particularly Melisococcus plutonius [(ex.
View Article and Find Full Text PDFHoney bees play a major role in crop pollination but have experienced declining health throughout most of the globe. Despite decades of research on key honey bee stressors (e.g.
View Article and Find Full Text PDFThe skin microbiome is an extensive community of bacteria, fungi, mites, viruses and archaea colonizing the skin. Fluctuations in the composition of the skin microbiome have been observed in atopic dermatitis (AD) and food allergy (FA), particularly in early life, established disease, and associated with therapeutics. However, AD is a multifactorial disease characterized by skin barrier aberrations modulated by genetics, immunology, and environmental influences, thus the skin microbiome is not the sole feature of this disease.
View Article and Find Full Text PDFMalassezia globosa is abundant and prevalent on sebaceous areas of the human skin. Genome annotation reveals that M. globosa possesses a repertoire of secreted hydrolytic enzymes relevant for lipid and protein metabolism.
View Article and Find Full Text PDFThe ZAKα-driven ribotoxic stress response (RSR) is activated by ribosome stalling and/or collisions. Recent work demonstrates that RSR also plays a role in innate immunity by activating the human NLRP1 inflammasome. Here, we report that ZAKα and NLRP1 sense bacterial exotoxins that target ribosome elongation factors.
View Article and Find Full Text PDFTo evaluate outcomes of breast lesions assessed at our institution as probably benign (Breast Imaging Reporting and Data System [BI-RADS] category 3) with an expected malignancy rate of less than or equal to 2 %. Average-risk women with a BI-RADS 3 assessment following mammographic and/or ultrasound evaluation at our institution between January 1 and December 31, 2017 were included. Cancer yield was calculated within 90 days and at 6-month intervals up to 36 months.
View Article and Find Full Text PDFBackground: Protecting the skin barrier in early infancy may prevent atopic dermatitis (AD). We investigated if daily emollient use from birth to 2 months reduced AD incidence in high-risk infants at 12 months.
Methods: This was a single-center, two-armed, investigator-blinded, randomized controlled clinical trial (NCT03871998).
Atopic dermatitis (AD) is a skin inflammatory disease in which the opportunistic pathogen is prevalent and abundant. harbors several secreted virulence factors that have well-studied functions in infection models, but it is unclear whether these extracellular microbial factors are relevant in the context of AD. To address this question, we designed a culture-independent method to detect and quantify virulence factors expressed at the skin sites.
View Article and Find Full Text PDFHuman NLRP1 (NACHT, LRR, and PYD domain-containing protein 1) is an innate immune sensor predominantly expressed in the skin and airway epithelium. Here, we report that human NLRP1 senses the ultraviolet B (UVB)- and toxin-induced ribotoxic stress response (RSR). Biochemically, RSR leads to the direct hyperphosphorylation of a human-specific disordered linker region of NLRP1 (NLRP1) by MAP3K20/ZAKα kinase and its downstream effector, p38.
View Article and Find Full Text PDFBackground: The ichthyoses are rare genetic keratinizing disorders that share the characteristics of an impaired epidermal barrier and increased risk of microbial infections. Although ichthyotic diseases share a T helper (Th) 17 cell immune signature, including increased expression of antimicrobial peptides, the skin microbiota of ichthyoses is virtually unexplored.
Objectives: To analyse the metagenome profile of skin microbiome for major congenital ichthyosis subtypes.
Background: Atopic dermatitis (AD) is a common chronic skin condition in children (15-20%) that can significantly impair their quality of life. As a result of its relapsing nature and enrichment of Staphylococcus aureus during flares, clinical management can include eradicating S aureus from the skin of children; however, this does not extend to their healthy caregivers, who are potential reservoirs.
Objective: Our aim was to understand skin microbiome sharing and microbial features in children with AD and their healthy adult caregivers.
Background: Observational studies suggest an increased risk of eczema in children living in hard versus soft water areas, and there is, therefore, an interest in knowing whether softening water may prevent eczema. We evaluated the feasibility of a parallel-group assessor-blinded pilot randomized controlled trial to test whether installing a domestic ion-exchange water softener before birth in hard water areas reduces the risk of eczema in infants with a family history of atopy.
Methods: Pregnant women living in hard water areas (>250 mg/L calcium carbonate) in and around London UK, were randomized 1:1 antenatally to either have an ion-exchange water softener installed in their home or not (ie to continue to receive usual domestic hard water).