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

Journal: bioRxiv

Article Title: Epidermal Stem Cells Control Periderm Injury Repair via Matrix-Driven Specialization of Intercellular Junctions

doi: 10.1101/2025.07.02.662640

Figure Lengend Snippet: ( A ) Representative immunofluorescence images of P63, F-actin, and DAPI in both layers of the bilayer normal human epidermal keratinocytes (NHEK) cell culture system. DAPI image is z-depth color-coded. ( B ) Quantification of P63 intensity in Basal and Suprabasal cells (two-tailed unpaired t-test, p<0.0001, n=15 fields of view (FOV) containing 5-20 cells per FOV; 1 independent experiment). ( C ) Schematic of the two different gel constructs containing 100% collagen (Collagen) and 100% collagen gel coated with laminin (Col (LM-coated)). ( D ) Representative immunofluorescence z-stack cross sections of NHEKs cultured on each of the two gel systems. Cells were stained with F-actin and DAPI. ( E ) Representative immunofluorescence images of β-Catenin (CTNNB1) in culture on each gel type. Images are shown of the Suprabasal, Interlayer (between the Suprabasal and Basal), and the Basal cells. Immunofluorescence intensity is displayed using a 16-color scale. ( F ) Quantification of CTNNB1 intensity at Suprabasal junctions, Interlayer (between the Suprabasal and Basal), and Basal junctions in NHEKs cultured on the two gel systems. For each graph, intensity was normalized to the Collagen Gel Group (two-tailed unpaired t test (Suprabasal and Basal) and two-tailed Mann-Whitney test (Interlayer), p = 0.0046 (Suprabasal), 0.2213 (Interlayer), and p<0.0001 (Basal), n = 41-53 cells; 1 independent experiment). ( G ) Representative immunofluorescence images of Desmoplakin (DSP) in culture on each gel type. Images are shown of the Suprabasal, Interlayer (between the Suprabasal and Basal), and the Basal cells. Immunofluorescence intensity is represented as 16 colors. ( H ) Quantification of Desmoplakin intensity at Suprabasal junctions, Interlayer (between the Suprabasal and Basal), and Basal junctions in NHEKs cultured on the two gel systems. For each graph, intensity was normalized to the Collagen Gel Group (two-tailed unpaired t test (Suprabasal and Interlayer) and two-tailed Mann-Whitney test (Basal), p = 0.0042 (Suprabasal) and p<0.0001 (Interlayer and Basal), n = 40-50 cells; 1 independent experiment).

Article Snippet: Normal human epidermal keratinocytes (NHEKs) were purchased from Promo Cell (C-12001) from a 4-year-old Caucasian male donor (Lot #: 494Z030.1).

Techniques: Immunofluorescence, Cell Culture, Two Tailed Test, Construct, Staining, MANN-WHITNEY

Journal: bioRxiv

Article Title: Epidermal Stem Cells Control Periderm Injury Repair via Matrix-Driven Specialization of Intercellular Junctions

doi: 10.1101/2025.07.02.662640

Figure Lengend Snippet: ( A ) Representative images of immunofluorescence staining specific to Human ECM proteins (rows), produced by the NHEKs when cultured on different animal-derived ECM scaffolds (columns). ( B-D ) Quantification of respective Human ECM proteins produced by NHEKs cultured on each of the gel systems (see ). (two-tailed Welch’s t test, p = 0.5393 (Collagen I), 0.2503 (Collagen IV), and 0.2227 (Laminin), n = 30-32 Field of views; 1 independent experiment). ( E ) Threshold images of interlayer Desmoplakin plaques in NHEKs cultured on each of the gel systems. ( F ) Quantification of Desmoplakin area between cell layers normalized to the collagen gel condition (Mann-Whitney test, p<0.0001, n= 936-1211 plaques; 1 independent experiment).

Article Snippet: Normal human epidermal keratinocytes (NHEKs) were purchased from Promo Cell (C-12001) from a 4-year-old Caucasian male donor (Lot #: 494Z030.1).

Techniques: Immunofluorescence, Staining, Produced, Cell Culture, Derivative Assay, Two Tailed Test, MANN-WHITNEY