normal human epidermal keratinocytes  (PromoCell)

Journal: Applied and Environmental Microbiology

Article Title: Skin Staphylococcus species differentially modulate keratinocyte cytokine secretion in response to UVB

doi: 10.1128/aem.01549-25

Figure Lengend Snippet: Dose-dependent effects on cytokine secretion. NHEKs (p3–5) cultured to 80% confluency were irradiated at 17–33 mJ/cm². Supernatants were collected 24 h post-irradiation and assessed via cytokine array ( A ) or via ELISA for IL-6 ( B ), IL-8 ( C ), CCL20 ( D ), and TNF-α ( E ). ELISA data are presented as mean ± SD. **** P < 0.0001, *** P < 0.001, ** P < 0.01, and * P < 0.05, as determined via one-way ANOVA followed by Tukey test.

Article Snippet: Pooled ( n = 3), normal human epidermal keratinocytes (NHEKs from juvenile foreskin, Promocell C-12005; passages 1–5) were routinely cultured in keratinocyte growth medium (KGM-2, Promocell).

Techniques: Cell Culture, Irradiation, Enzyme-linked Immunosorbent Assay

Journal: Applied and Environmental Microbiology

Article Title: Skin Staphylococcus species differentially modulate keratinocyte cytokine secretion in response to UVB

doi: 10.1128/aem.01549-25

Figure Lengend Snippet: Exposure to a skin PMC elevates cytokine secretion regardless of UVB exposure. NHEKs (p2–5) were treated with PBS (PBS, no UVB) or S. epidermidis, S. hominis, M. luteus, C. tuberculostearicum, and C. acnes for 30–90 min and subsequently exposed to UVB (33 mJ/cm²). Supernatants were collected 24 h post-inoculation with each organism, and the effects of the skin microbial PMC ± UVB on IL-6 ( A ), IL-8 ( B ), TNF-α ( C ), and CCL20 ( D ) secretion were assessed using ELISA. ** P < 0.01 and * P < 0.05, as determined via one-way ANOVA followed by Tukey test.

Article Snippet: Pooled ( n = 3), normal human epidermal keratinocytes (NHEKs from juvenile foreskin, Promocell C-12005; passages 1–5) were routinely cultured in keratinocyte growth medium (KGM-2, Promocell).

Techniques: Enzyme-linked Immunosorbent Assay

Journal: Applied and Environmental Microbiology

Article Title: Skin Staphylococcus species differentially modulate keratinocyte cytokine secretion in response to UVB

doi: 10.1128/aem.01549-25

Figure Lengend Snippet: UVB impacts the relative abundance of skin commensals in a polymicrobial skin community. NHEKs (p2–5) were incubated with a polymicrobial community for 90 min, media replaced, and cultures exposed to 33 mJ/cm2 UVB or left unirradiated (no UVB). Polymicrobial community composition was assessed 24 h post-treatment via qPCR, where relative proportions of each organism were calculated via species-specific standard curves and presented as collated data ( A , results for C. tuberculostearicum and M. luteus are not visible in the graph, as abundance was <1% of the total community) and UVB induced changes on individual species within the community of S. epidermidis ( B ), S. hominis ( C ), C. acnes ( D ), M. luteus ( E ), and C. tuberculostearicum ( F ). Data are presented as mean ± SD. ** P < 0.01 and * P < 0.05, as determined via unpaired t -test.

Article Snippet: Pooled ( n = 3), normal human epidermal keratinocytes (NHEKs from juvenile foreskin, Promocell C-12005; passages 1–5) were routinely cultured in keratinocyte growth medium (KGM-2, Promocell).

Techniques: Incubation

Journal: Applied and Environmental Microbiology

Article Title: Skin Staphylococcus species differentially modulate keratinocyte cytokine secretion in response to UVB

doi: 10.1128/aem.01549-25

Figure Lengend Snippet: UVB exacerbates S. epidermidis -induced cytokine secretion, while S. hominis amplified secretion of IL-8 and CCL20 regardless of UVB exposure. NHEKs (p2–5) were incubated with media alone, S. hominis, or S. epidermidis for 30–60 min, media replaced with PBS, and exposed to UVB (0–33 mJ/cm²). Adherent bacteria were then co-cultured with NHEKs for 24 h, following which supernatants were collected to assess the effects on IL-6 ( A and E ), CCL20 ( B and F ), IL-8 ( C and G ), and TNF-α ( D and H ). Significance was assessed via one-way ANOVA followed by Tukey test, where ** P < 0.01, *** P < 0.001, and **** P < 0.0001.

Article Snippet: Pooled ( n = 3), normal human epidermal keratinocytes (NHEKs from juvenile foreskin, Promocell C-12005; passages 1–5) were routinely cultured in keratinocyte growth medium (KGM-2, Promocell).

Techniques: Amplification, Incubation, Bacteria, Cell Culture

Journal: Applied and Environmental Microbiology

Article Title: Skin Staphylococcus species differentially modulate keratinocyte cytokine secretion in response to UVB

doi: 10.1128/aem.01549-25

Figure Lengend Snippet: S. hominis diminishes S. epidermidis- enhanced cytokine responses to UVR. NHEKs (p2–5) were incubated with media, S. hominis , S. epidermidis, or both for 30–60 min, media replaced with PBS, and subsequently exposed to UVB (0–20 mJ/cm²). Twenty-hours post-microbial inoculation, supernatants were collected and effects on cytokine secretion assessed by ELISA ( A–D ). **** P < 0.0001, *** P < 0.001, ** P < 0.01, and * P < 0.05, as determined via one-way ANOVA followed by Tukey test.

Article Snippet: Pooled ( n = 3), normal human epidermal keratinocytes (NHEKs from juvenile foreskin, Promocell C-12005; passages 1–5) were routinely cultured in keratinocyte growth medium (KGM-2, Promocell).

Techniques: Incubation, Enzyme-linked Immunosorbent Assay

Journal: Frontiers in Molecular Biosciences

Article Title: Transcriptomic profiling of chlorogenic acid and taurine treatment in human skin cells provides insights into cellular senescence mechanisms

doi: 10.3389/fmolb.2026.1748185

Figure Lengend Snippet: Inferred transcriptomic architecture of antioxidant-responsive DEGs. (A) , Number of identified antioxidant-responsive DEGs in each human skin cell type. Bar heights indicate the number of DEGs identified under each treatment condition, with values labeled above each bar. Dark-colored segments represent the subset of AR-DEGs among the antioxidant-responsive DEGs. Bar colors correspond to different treatment conditions. (B) , Regulatory network of DEGs inferred using DoRothEA. Circles represent genes with directed edges from transcription factors to their predicted targets based on the DoRothEA regulon. Nodes are colored by log 2 FC from differential expression analysis in epidermal keratinocytes (above) and melanocytes (below). Gene symbols and log 2 FC values are labeled on each node. Genes with |log 2 FC| ≤ 0.585 are shown with lighter colors and gray text. Aging-related DEGs are marked with an asterisk next to the gene names. (C) , Antioxidative and anti-inflammatory pathways associated with DEGs. Each bar represents a pathway or GO term ( y -axis) identified in this study, with the corresponding −log 10 adjusted P -values from gprofiler2 ( x -axis). The vertical dashed line indicates the significance threshold of adjusted P -value = 0.05. (D) , A selected molecular model illustrates interaction between treatment of CGA and taurine and genes related with anti-aging mechanisms. Abbreviations: CGA, chlorogenic acid; CGA + Tau, combined treatment of chlorogenic acid and taurine; log 2 FC, Bayesian shrinkage estimator for log 2 fold change.

Article Snippet: Normal Human Epidermal Keratinocytes (Cat. no. PCS-200–010; ATCC, Manassas, VA, United States) were cultured in Keratinocyte Growth Medium (Lonza, KGMTM Gold, Cat. no. 00192060; BS, Switzerland) supplemented with 10% fetal bovine serum (Gibco, Waltham, MA, United States), 100 U/mL penicillin, and 100 μg/mL streptomycin (Gibco).

Techniques: Labeling, Quantitative Proteomics

Journal: Frontiers in Immunology

Article Title: A skin isolate of Micrococcus luteus negates the Staphylococcus aureus- induced release of type 2 cytokines from keratinocytes

doi: 10.3389/fimmu.2026.1711723

Figure Lengend Snippet: The ability to negate S. aureus -induced cytokine secretion from keratinocytes is a strain specific effect of M. luteus CFCS. (A, B) NHEK were treated with FSA or co-treated with FSA and skin bacterial CFCS for 24 h before quantifying IL-33 and TSLP in cell culture medium using ELISA. Stimulation of NHEK with FSA caused an increase in IL-33 and TSLP release. (B) Co-treatment with skin isolated M. luteus FAML CFCS negated FSA-induced release of IL-33 and TSLP. (C) Co-treatment with the M. luteus type strain NCTC 2665 had no effect on FSA-induced IL-33 and TSLP release. Data are expressed as mean ± SEM (n≥3). P values determined by one-way ANOVA *P ≤ 0.05 **P ≤ 0.01 ***P ≤ 0.001 ****P ≤ 0.0001 compared with FSA treated NHEK; ns, non-significant.

Article Snippet: Primary Normal Human Epidermal Keratinocytes (NHEK) (PromoCell, Heidelberg, Germany) were isolated from the epidermis of juvenile foreskin from pooled donors and grown in KGM supplemented with KGM SupplementMix (Promocell) at 37 ̊C in a humidified atmosphere of 5% CO 2 .

Techniques: Cell Culture, Enzyme-linked Immunosorbent Assay, Isolation

Journal: Frontiers in Immunology

Article Title: A skin isolate of Micrococcus luteus negates the Staphylococcus aureus- induced release of type 2 cytokines from keratinocytes

doi: 10.3389/fimmu.2026.1711723

Figure Lengend Snippet: The efficacious molecule secreted by M. luteus FAML is a putative protein. M. luteus FAML was cultured for 1, 2, 4, 6 and 24 h before harvesting CFCS. NHEK were co-cultured with FSA and M. luteus FAML CFCS for 24 h before measuring (A) TSLP and (B) IL-33 in cell culture medium using ELISA. (C) M . luteus FAML CFCS collected at 24 h lost activity against FSA-induced IL-33 and TSLP release in NHEK after heat treatment (HT) to 85°C. (D) Proteins within M. luteus FAML CFCS were precipitated using acetone, then reconstituted in cell culture medium before testing for activity using the same model. Activity was retained within the protein precipitate (PP). Data are expressed as mean ± SEM (n≥4). P values determined by one-way ANOVA *P ≤ 0.05 **P ≤ 0.01 ***P ≤ 0.001 ****P ≤ 0.0001 compared with FSA treated NHEK; ns, non-significant.

Article Snippet: Primary Normal Human Epidermal Keratinocytes (NHEK) (PromoCell, Heidelberg, Germany) were isolated from the epidermis of juvenile foreskin from pooled donors and grown in KGM supplemented with KGM SupplementMix (Promocell) at 37 ̊C in a humidified atmosphere of 5% CO 2 .

Techniques: Cell Culture, Enzyme-linked Immunosorbent Assay, Activity Assay

Journal: Frontiers in Immunology

Article Title: A skin isolate of Micrococcus luteus negates the Staphylococcus aureus- induced release of type 2 cytokines from keratinocytes

doi: 10.3389/fimmu.2026.1711723

Figure Lengend Snippet: Recombinant PADP negates FSA-induced IL-33 and TSLP release from NHEK. NHEK were co-cultured with FSA and rPADP for 24 h before measuring IL-33 and TSLP in the cell culture medium using ELISA. The rPADP negated FSA-induced IL-33 and TSLP release in NHEK. Data are expressed as mean ± SEM (n≥3). P values determined by one-way ANOVA *P ≤ 0.05 **P ≤ 0.01 ****P ≤ 0.0001 compared with FSA treated NHEK.

Article Snippet: Primary Normal Human Epidermal Keratinocytes (NHEK) (PromoCell, Heidelberg, Germany) were isolated from the epidermis of juvenile foreskin from pooled donors and grown in KGM supplemented with KGM SupplementMix (Promocell) at 37 ̊C in a humidified atmosphere of 5% CO 2 .

Techniques: Recombinant, Cell Culture, Enzyme-linked Immunosorbent Assay