human normal human epidermal keratinocytes nhek  (PromoCell)

Journal: iScience

Article Title: Topical application of urolithin A activates mitophagy and enhances mitochondrial function to promote skin longevity

doi: 10.1016/j.isci.2026.117646

Figure Lengend Snippet: UA beneficial impact on human keratinocytes and reconstituted human epidermis (A) Mitochondrial respiration (basal and maximal) assessed as oxygen consumption rate (OCR) in human dermal keratinocytes after 72 h of differentiation from young donor treated with DMSO for 24 h or the indicated dose of UA. ∗ p < 0.05 and ∗∗∗ p < 0.001 after one-way ANOVA. Error bars represent mean ± SEM. (B) TOMM20 immunostaining of skin epidermis in a human full-thickness skin model from an old donor treated with or without UA 1 μM for 25 days. Data expressed as antibody staining signal over imaging field. ∗ p < 0.05 and ∗∗∗∗ p < 0.0001 after unpaired t test one-way ANOVA. Error bars represent mean ± SEM. Scale bars, 50 μm. (C) Relative gene expression of PINK1 and PARK2 in reconstructed human epidermis (RHE). RHE tissues were moisturized for 24 h with or without 1% Mitopure, and relative expression levels of PINK1 and PARK2 were quantified. Statistical analysis was performed using one-way ANOVA (∗ p < 0.05; ∗∗ p < 0.01). Error bars represent mean ± SEM. (D) Interleukin 6 levels normalized to cell viability in keratinocytes. Keratinocytes were stimulated with a pro-inflammatory cytokine mix for 24 h then treated for an additional 24 h with either DMSO or 1 μM UA. IL-6 secretion was quantified and normalized to cell viability. Statistical analysis was performed using one-way ANOVA (∗∗∗∗ p < 0.0001). Error bars represent mean ± SEM. (E) p16 immunostaining in a human full-thickness skin model from an old donor treated with or without UA 1 μM for 25 days. Data expressed as antibody staining signal over imaging field. ∗∗∗∗ p < 0.0001 after unpaired t test. Error bars represent mean ± SEM. Scale bars, 50 μm. (F) Ki67 immunostaining in a human full-thickness skin model from an old donor treated with or without UA 1 μM for 25 days. Data expressed as number of Ki67 positive cells normalized over μm of dermal epidermal junction (count/μm) ∗∗∗∗ p < 0.0001 after unpaired t test. Error bars represent mean ± SEM. Scale bars, 50 μm. (G) Keratin 10 immunostaining in a human full-thickness skin model from an old donor treated with or without UA 1 μM for 25 days. Data expressed as fluorescence intensity over epidermis area. ∗∗∗∗ p < 0.0001 after unpaired t test. Error bars represent mean ± SEM. Scale bars, 50 μm.

Article Snippet: Human: Normal Human Epidermal Keratinocytes (NHEK) , PromoCell , Cat#C-12003; Lot#479Z011.1.

Techniques: Immunostaining, Staining, Imaging, Gene Expression, Expressing, Analysis, Fluorescence

Journal: iScience

Article Title: Topical application of urolithin A activates mitophagy and enhances mitochondrial function to promote skin longevity

doi: 10.1016/j.isci.2026.117646

Figure Lengend Snippet:

Article Snippet: Human: Normal Human Epidermal Keratinocytes (NHEK) , PromoCell , Cat#C-12003; Lot#479Z011.1.

Techniques: Binding Assay, Ex Vivo, Recombinant, Metals, Enzyme-linked Immunosorbent Assay, Reverse Transcription, Cell Viability Assay, Staining, DC Protein Assay, Gene Expression, Glass, Software, Imaging, Microscopy, Real-time Polymerase Chain Reaction

Journal: Communications Biology

Article Title: The MYB-related transcription factor MYPOP acts as a selective regulator of cancer cell growth

doi: 10.1038/s42003-026-10272-2

Figure Lengend Snippet: a MYPOP expression in normal (N) and tumor (T) cells detected by Western blotting showing endogenous protein levels of MYPOP in normal human epidermal keratinocytes (NHEK) and cervical cancer cells (HeLa). In addition, the expression of GFP and MYPOP in HeLa cells after transfection with pcDNA3.1-MYPOP (MYPOP), pEGFP-C3-MYPOP (GFP-MYPOP) or corresponding controls (pcDNA3.1, Control and pEGFP-C3, GFP-Control) is shown. MYPOP and GFP were stained using anti-MYPOP pAb and anti-GFP mAb. GAPDH staining was used as a loading control. b – i GFP-Control or GFP-MYPOP expressing HeLa cells. b , c Lower ( b ) and higher ( c ) magnification for representative fluorescence microscopy images of GFP-Control or GFP-MYPOP (green) expressing cells 24 h post transfection (p.t.). Cell nuclei were stained using Hoechst 33342 (blue). d , e Representative fluorescence microscopy images treated as in ( c ) showing cytoplasmic, nucleocytoplasmic ( d ) and nuclear ( e ) localization as well as co-localization of GFP-MYPOP (green) and DNA (blue). f Co-localization analysis between GFP or GFP-MYPOP and DNA (Hoechst) using Pearson correlation coefficient (PCC). At least 10 GFP-positive cells were analyzed for each treatment and biological replicate ( n = 3). Values are shown as mean + SD. Statistical significance was determined with p = 0.0001 comparing GFP-MYPOP and GFP-Control. g Representative fluorescence microscopy images of GFP-MYPOP (green) expressing cells showing shrunken or fragmented nuclei at 24 h p.t. Cell nuclei (blue) as above. h , i Quantification of fragmented and shrunken nuclei at 24 h p.t ( h ) and 48 h p.t ( i ). At least 100 GFP-positive cells were analyzed for each treatment, time point and biological replicate, respectively. Values ( n = 3) are shown as mean + SD. Statistical significance was determined with p (24 h p.t.) = 0.0036 and p (48 h p.t.) = 0.0428 comparing GFP-MYPOP and GFP-Control.

Article Snippet: Normal Human Epidermal Keratinocytes (NHEK) were purchased from PromoCell, Germany and were cultivated according to the manufacturer’s instructions.

Techniques: Expressing, Western Blot, Transfection, Control, Staining, Fluorescence, Microscopy

Journal: Communications Biology

Article Title: The MYB-related transcription factor MYPOP acts as a selective regulator of cancer cell growth

doi: 10.1038/s42003-026-10272-2

Figure Lengend Snippet: a Endogenous protein levels of MYPOP in untreated cancer cell lines. Normal skin cells (NHEK) and normal lung cells (181576 N, 181652 N) served as controls. GAPDH or β-actin staining was used as loading control. b Cancer cells were transfected with either a MYPOP expression plasmid or a control plasmid, selected for 6–12 days with G418, fixed, and stained with crystal violet. The cell-covered area was quantified (relative area). Values are presented as mean + SD. The mean for control-transfected cells was set to 100% (dotted line). Statistical significance was determined by comparing control and MYPOP expressing cells with p = 0.0022 for Huh7 ( n = 3), p = 0.0028 for HEK293 ( n = 5), p = 0.0064 for MCF7 ( n = 4), p = 0.0294 for HCT116 ( n = 3), p = 0.0106 for HeLa ( n = 3), p = 0.0003 for A549 ( n = 3), and p = 0.0026 for 2106 T ( n = 4).

Article Snippet: Normal Human Epidermal Keratinocytes (NHEK) were purchased from PromoCell, Germany and were cultivated according to the manufacturer’s instructions.

Techniques: Staining, Control, Transfection, Expressing, Plasmid Preparation

Journal: Communications Biology

Article Title: The MYB-related transcription factor MYPOP acts as a selective regulator of cancer cell growth

doi: 10.1038/s42003-026-10272-2

Figure Lengend Snippet: a Protein expression of untreated, control mRNA and MYPOP mRNA-transfected HeLa cells and NHEK cells, as indicated at different time points post transfection (6 h–54 h) was analyzed by western blotting using anti-MYPOP and anti-GAPDH antibodies. Under conditions of low protein loading and short exposure times, endogenous MYPOP is not detected in NHEK, as these parameters are optimized to prevent oversaturation of overexpressed MYPOP at 6 h p.t. Detection of endogenous MYPOP increases at later time points, reflecting cell growth and higher total protein content. Lower panel: optical microscope overview images of untreated, control mRNA and MYPOP mRNA-transfected HeLa cells (left panel) and NHEK cells (right panel) at 6 h and 54 h after mRNA transfection. b Growth curves (object counts per image, measurement every 2 h) of untreated, control mRNA and MYPOP mRNA-transfected HeLa, NHEK, CaSki, HaCaT, HCT116, and 2106 T cells at the indicated time points. Statistical significance ( n = 4 for HeLa, n = 3 for all others) was determined between Control and MYPOP cell counts at 70 h or 72 h p.t. as indicated with p = 0.0203 for HeLa, p = 0.0441 for CaSki, p = 0.4720 for HCT116, p = 0.2424 for NHEK, p < 0.0001 for HaCaT, and p = 0.0152 for 2106 T. c Left: MYPOP and GAPDH protein expression in Hela wild-type (WT) and MYPOP knockout (KO) cells. Statistical significance ( n = 3) between WT and KO cells was determined with p = 0.0014 for MYPOP band intensities. Center: optical microscope overview images of HeLa WT and KO cells. Right: growth curve of HeLa WT and KO cells. Statistical significance ( n = 4) was determined with p = 0.6099 at 72 h t.p.

Article Snippet: Normal Human Epidermal Keratinocytes (NHEK) were purchased from PromoCell, Germany and were cultivated according to the manufacturer’s instructions.

Techniques: Expressing, Control, Transfection, Western Blot, Microscopy, Knock-Out

Journal: Communications Biology

Article Title: The MYB-related transcription factor MYPOP acts as a selective regulator of cancer cell growth

doi: 10.1038/s42003-026-10272-2

Figure Lengend Snippet: Volcano plots depicting gene expression changes of control and MYPOP mRNA-transfected HeLa and NHEK cells at 6 h and 24 h p.t. as indicated. The labels display the overlapping DEGs, which were selected from the initial RNA-Seq experiment shown in Fig. , comprising the 30 top DEGs (15 up, 15 downregulated) and the 27 ‘cell cycle’ genes. Significantly downregulated candidates with adjusted p ≤ 0.05 are shown in blue, and upregulated candidates with adjusted p ≤ 0.05 are shown in red.

Article Snippet: Normal Human Epidermal Keratinocytes (NHEK) were purchased from PromoCell, Germany and were cultivated according to the manufacturer’s instructions.

Techniques: Gene Expression, Control, Transfection, RNA Sequencing

Journal: Frontiers in Immunology

Article Title: Staphylococcus epidermidis prevents UV-induced skin aging by suppressing TLR3-mediated senescence

doi: 10.3389/fimmu.2026.1796085

Figure Lengend Snippet: Staphylococcus epidermidis inhibits UVB-induced senescence in keratinocytes. (A) Neonatal human epidermal keratinocytes (NHEKs) at 90% confluence were irradiated with 10 mJ/cm 2 UVB, followed by treatment with 75 μg/mL ≤10kDa S. epi . β-gal staining was performed 24 hours post-treatment. The proportion of senescent cells was quantified using Image (J, B) After UVB irradiation, different concentrations of ≤10kDa S. epi were added to NHEKs. RNA was isolated 24 hours later, and P16 expression was measured by quantitative RT-PCR with β-actin as the internal control. (C) NHEKs at 90% confluence were irradiated with 10mJ/cm 2 UVB, followed by treatment with 75μg/mL ≤10kDa S. epi . Six hours later, intracellular ROS were labeled with DCFH-DA and visualized using fluorescence microscope (excitation: 488 nm; emission: 525 nm), and fluorescence intensity was quantified using Image (J, D) NHEKs were treated with different concentrations of ≤10kDa S. epi . Six hours later, proteins were extracted for γH2Ax analysis, and densitometric analysis of protein bands were quantified by Image (J) Immunoblotting results are representative of three independent experiments performed with independent cultured keratinocytes. (E) NHEKs were irradiated with 10mJ/cm 2 UVB and treated with 75μg/mL ≤10kDa S. epi . Six hours post-treatment, γH2Ax expression was visualized by immunofluorescence, and fluorescence intensity was quantified using Image (J, F) After UVB exposure (10mJ/cm 2 ), NHEKs were treated with different concentrations of ≤10kDa S. epi . RNA was isolated 24 hours later, and the expressions of IL-6 , TNFα and IL-1β was analyzed by quantitative RT-PCR using β-actin as internal control. (G) Following UVB irradiation (10mJ/cm 2 ), NHEKs were treated with different concentrations of ≤10kDa S. epi . 24 hours later, cell culture supernatants were collected, and IL-6 and IL-1β secretion was measured by ELISA. Data represent mean ± SEM from independent biological replicates ( n = 3). All the experiments have been repeated three times. Statistical significances were evaluated by One-way ANOVA. * p < 0.05, ** p < 0.01, *** p < 0.001, **** p < 0.0001, n.s., no significance.

Article Snippet: Neonatal human epidermal keratinocytes (NHEKs) and neonatal human fibroblasts were purchased from Lifeline Cell Technology.

Techniques: Irradiation, Staining, Isolation, Expressing, Quantitative RT-PCR, Control, Labeling, Fluorescence, Microscopy, Western Blot, Cell Culture, Immunofluorescence, Enzyme-linked Immunosorbent Assay

Journal: Frontiers in Immunology

Article Title: Staphylococcus epidermidis prevents UV-induced skin aging by suppressing TLR3-mediated senescence

doi: 10.3389/fimmu.2026.1796085

Figure Lengend Snippet: Staphylococcus epidermidis inhibits fibroblast senescence by inhibiting SASP secretion from UVB-irradiated keratinocytes. (A) Schematic representation of the experimental design. NHEKs were cultured to 90% confluence and then exposed to 10 mJ/cm 2 UVB for induction. Subsequently, 75μg/mL of ≤10kDa S. epi was added to coculture for 48 hours. The conditioned medium containing SASP factors was collected by centrifugation at 2, 000 rpm for 20 minutes, mixed with fresh DMEM at a 1:2 ratio, and the final serum concentration was adjusted to 10%. The mixed medium was used to culture primary human fibroblasts for 48 hours. (B) Fibroblasts were stained with senescence-associated β-gal, and the percentage of senescent cells was quantified by Image (J, C) Protein levels of P16 and P21 in fibroblasts were analyzed by western blotting. Densitometric analysis of protein bands were quantified by Image (J, D) RT-PCR analysis of RNA isolated from fibroblasts was performed to assess the expression of P16, P21 , P53 , TNFα , IL-6 , IL-1β , and MMP1 , with β-actin as the internal control. Con-SASP, SASP collected from control NHEKs; S.epi -SASP, SASP collected from NHEKs treated with 75μg/mL of ≤10kDa S.epi ; UVB-SASP, SASP collected from NHEKs treated with UVB; UVB+ S.epi -SASP, SASP collected from NHEKs treated with UVB and 75μg/mL of ≤10kDa S.epi . Data represent mean ± SEM with n = 3. All the experiments have been repeated three times. Statistical significances were analyzed by One-way ANOVA. ** p < 0.01, *** p < 0.001, **** p < 0.0001.

Article Snippet: Neonatal human epidermal keratinocytes (NHEKs) and neonatal human fibroblasts were purchased from Lifeline Cell Technology.

Techniques: Irradiation, Cell Culture, Centrifugation, Concentration Assay, Staining, Western Blot, Reverse Transcription Polymerase Chain Reaction, Isolation, Expressing, Control

Journal: Frontiers in Immunology

Article Title: Staphylococcus epidermidis prevents UV-induced skin aging by suppressing TLR3-mediated senescence

doi: 10.3389/fimmu.2026.1796085

Figure Lengend Snippet: LP78 inhibits UVB-induced keratinocyte senescence. (A) NHEK at 90% confluency were irradiated with 10mJ/cm 2 UVB, followed by treatment with different concentrations of LP78. RNA was extracted 24 hours later, and P16 expression was detected by RT-PCR, with β-actin as the internal control. (B) NHEKs at 90% confluency were irradiated with 10mJ/cm 2 UVB and treated with different concentrations of LP78. Cell lysates were collected after 24 hours, and P16 and γH2Ax levels were analyzed by western blotting. Densitometric analysis of protein bands were quantified by Image (J, C) NHEKs at 90% confluency were irradiated with 10mJ/cm 2 UVB and treated with 10μg/mL LP78. Six hours post-treatment, intracellular ROS were visualized using fluorescence microscope and the intensity was quantified using Image (J, D) NHEK at 90% confluency were irradiated with 10mJ/cm 2 UVB and treated with different concentrations of LP78. RNA was extracted 24 hours later, and the expression of IL-6 , TNFα and IL-1β was measured by RT-PCR, with β-actin as the internal control. (E) NHEKs at 90% confluency were irradiated with 10mJ/cm 2 UVB and treated with different concentrations of LP78. After 24 hours, culture supernatants were collected, and the secretion of IL-6 and IL-1β was quantified by ELISA. Data represent mean ± SEM with n = 3. All the experiments have been repeated three times. Statistical significances were analyzed by One-way ANOVA. *** p < 0.001, **** p < 0.0001, n.s., no significance.

Article Snippet: Neonatal human epidermal keratinocytes (NHEKs) and neonatal human fibroblasts were purchased from Lifeline Cell Technology.

Techniques: Irradiation, Expressing, Reverse Transcription Polymerase Chain Reaction, Control, Western Blot, Fluorescence, Microscopy, Enzyme-linked Immunosorbent Assay

Journal: Frontiers in Immunology

Article Title: Staphylococcus epidermidis prevents UV-induced skin aging by suppressing TLR3-mediated senescence

doi: 10.3389/fimmu.2026.1796085

Figure Lengend Snippet: UV-induced skin photoaging is dependent on TLR3 activation, and Staphylococcus epidermidis and LP78 inhibit TLR3-mediated SASP factors. (A) A long-term photoaging model was established using WT and Tlr3 −/− C57BL/6 mice ( n = 5-7). The dorsal skin of each mouse was divided into upper (shield with tin foil) and lower (exposed) regions. The lower region was irradiated with UV as shown in Figure 1A . Representative photographs of dorsal skin were taken at the end of the experiment for HE staining. (B) Epidermal thickness of dorsal skin from mice treated as (A) was quantified using Image J software. (C) Masson’s trichrome staining of dorsal skin from mice treated as (A) was performed to evaluate dermal collagen content. (D) Western blot analysis of P16, P21 and γH2Ax protein expression in dorsal skin tissues from mice treated as (A) . Densitometric analysis of protein bands were quantified by Image (J, E) ELISA measurement of Il-6 and Il-1β in dorsal skin tissues from mice treated as (A) . (F) RT-PCR analysis of Il-6 , Tnfα , Il-1β and Mmp1 , with β-actin as an internal control. (G) NHEKs with or without TLR3 silencing were irradiated with 10mJ/cm 2 UVB at 90% confluence. Following UVB exposure, cells were treated with 75μg/mL of ≤10kDa S. epi or 10μg/mL of LP78. RNA was extracted 12h hours post-treatment, and IL-6 , TNFα and IL-1β mRNA expression was assessed by RT-PCR, with β-Actin as a reference gene. (I) Supernatants were collected from the same cultures in (G) , and the secretion of IL-6 and IL-1β was measured by ELISA. Data represent mean ± SEM with n = 3-7. All the experiments have been repeated twice or three times. Statistical significances were analyzed by Two-way ANOVA. ** p < 0.01, **** p < 0.0001.

Article Snippet: Neonatal human epidermal keratinocytes (NHEKs) and neonatal human fibroblasts were purchased from Lifeline Cell Technology.

Techniques: Activation Assay, Irradiation, Staining, Software, Western Blot, Expressing, Enzyme-linked Immunosorbent Assay, Reverse Transcription Polymerase Chain Reaction, Control

Journal: Frontiers in Immunology

Article Title: Staphylococcus epidermidis prevents UV-induced skin aging by suppressing TLR3-mediated senescence

doi: 10.3389/fimmu.2026.1796085

Figure Lengend Snippet: Staphylococcus epidermidis and LP78 inhibit SASP factor expression through TRAF1 induction. (A) NHEKs were treated with 75μg/mL of ≤10kDa S. epi or 10μg/mL of LP78. RNA was extracted at different time points, and TRAF1 expression was assessed by RT-PCR, with β-actin as the internal control. (B) Western blot analysis of TRAF1 in NHEKs treated as in (A) . Densitometric analysis of protein bands were quantified by Image (J, C) NHEKs were transfected with siTRAF1 using jetPRIME at 60% confluency. After 24 hours, the cells were exposed to 10mJ/cm 2 UVB and treated with 75μg/mL of ≤10kDa S. epi or 10μg/mL of LP78. RNA was extracted after 12 hours post-treatment, and the expression of IL-6 , TNFα and IL-1β was analyzed by RT-PCR, with β-actin as the internal reference. (C) The supernatant from the same culture in (B) was analyzed by ELISA to measure IL-6 and IL-1β secretion. Data represent mean ± SEM with n = 3. All the experiments have been repeated three times. Statistical significances were analyzed by Two-way ANOVA. * p < 0.05, **** p < 0.0001, n.s., no significance.

Article Snippet: Neonatal human epidermal keratinocytes (NHEKs) and neonatal human fibroblasts were purchased from Lifeline Cell Technology.

Techniques: Expressing, Reverse Transcription Polymerase Chain Reaction, Control, Western Blot, Transfection, Enzyme-linked Immunosorbent Assay

Journal: Frontiers in Immunology

Article Title: Staphylococcus epidermidis prevents UV-induced skin aging by suppressing TLR3-mediated senescence

doi: 10.3389/fimmu.2026.1796085

Figure Lengend Snippet: Staphylococcus epidermidis and LP78 induce TRAF1 dependent on TLR2. (A) NHEKs were transfected with siTLR2 using jetPRIME at 60% confluency. After 24 hours, the cells were treated with 75μg/mL of ≤10kDa S. epi or 10μg/mL of LP78. Cell lysates was extracted after 12 hours post-treatment, and the expression of TRAF1 was analyzed Western blotting. Densitometric analysis of protein bands were quantified by Image (J, B) NHEKs were transfected with siTLR2 using jetPRIME at 60% confluency. After 24 hours, the cells were exposed to 10mJ/cm 2 UVB and treated with 75μg/mL of ≤10kDa S. epi or 10μg/mL of LP78. RNA was extracted after 12 hours post-treatment, and the expression of IL-6 , TNFα and IL-1β was analyzed by RT-PCR, with β-actin as the internal reference. (C) The supernatant from the same culture in (B) was analyzed by ELISA to measure IL-6 and IL-1β secretion. Data represent mean ± SEM with n = 3. All the experiments have been repeated three times. Statistical significances were analyzed by Two-way ANOVA. **** p < 0.0001, n.s., no significance.

Article Snippet: Neonatal human epidermal keratinocytes (NHEKs) and neonatal human fibroblasts were purchased from Lifeline Cell Technology.

Techniques: Transfection, Expressing, Western Blot, Reverse Transcription Polymerase Chain Reaction, 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: 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: Biomolecules

Article Title: Mandelamide Isolated from Prunus persica Flowers Attenuates TNF-α–Driven Oxidative and Inflammatory Responses in Human Skin Cells

doi: 10.3390/biom16050672

Figure Lengend Snippet: Effects of mandelamide ( 4 ) on pro-inflammatory mediator secretion in TNF-α–stimulated human epidermal keratinocytes (HEKs). Cells were pretreated with mandelamide at the indicated concentrations (12.5, 25, 50, and 100 μM) for 1 h, followed by stimulation with TNF-α for 12 or 24 h. The secretion levels of IL-6, IL-8, and IL-1β ( A ), as well as COX-2, PGE 2 , and nitric oxide (NO) ( B ), were quantified using ELISA, while NO production was additionally measured using the Griess assay. All experiments were performed according to the manufacturers’ protocols. Data are presented as mean ± SEM ( n = 3). Statistical significance was determined using one-way ANOVA followed by Tukey’s multiple comparisons test; # p < 0.05, ## p < 0.01, and ### p < 0.001 vs. control; * p < 0.05, ** p < 0.01, and *** p < 0.001 vs. TNF-α–treated group. Dexamethasone (Dexa) was used as a positive control in the IL-6 and IL-8 ELISAs.

Article Snippet: Human dermal fibroblasts (HDFs; CAT No. C-12302, adult donor) and human epidermal keratinocytes (HEKs; CAT No. C-12006, pooled adult donor) were purchased from PromoCell GmbH (Heidelberg, Germany).

Techniques: Enzyme-linked Immunosorbent Assay, Griess Assay, Control, Positive Control

Journal: Biomolecules

Article Title: Mandelamide Isolated from Prunus persica Flowers Attenuates TNF-α–Driven Oxidative and Inflammatory Responses in Human Skin Cells

doi: 10.3390/biom16050672

Figure Lengend Snippet: Effects of mandelamide ( 4 ) on the mRNA expression of MMPs and collagen-related genes in TNF-α/IFN-γ–stimulated human epidermal keratinocytes (HEKs). Cells were pretreated with mandelamide at the indicated concentrations (12.5, 25, 50, and 100 μM) for 1 h, followed by stimulation with TNF-α/IFN-γ for 24 h. The mRNA expression levels of MMP-1, MMP-2, MMP-9 ( A ), as well as COL1A1, COL1A2, COL3A1, and COL4A1 ( B ) were quantified by quantitative real-time PCR (qRT-PCR). All experiments were performed according to the manufacturers’ protocols. Data are presented as mean ± SEM ( n = 3). Statistical significance was determined using one-way ANOVA followed by Tukey’s multiple comparisons test; ## p < 0.05 and ### p < 0.001 vs. control; *, **, and *** p < 0.05, p < 0.01, and p < 0.001 vs. TNF-α/IFN-γ–treated group.

Article Snippet: Human dermal fibroblasts (HDFs; CAT No. C-12302, adult donor) and human epidermal keratinocytes (HEKs; CAT No. C-12006, pooled adult donor) were purchased from PromoCell GmbH (Heidelberg, Germany).

Techniques: Expressing, Real-time Polymerase Chain Reaction, Quantitative RT-PCR, Control

Journal: Biomolecules

Article Title: Mandelamide Isolated from Prunus persica Flowers Attenuates TNF-α–Driven Oxidative and Inflammatory Responses in Human Skin Cells

doi: 10.3390/biom16050672

Figure Lengend Snippet: Effects of mandelamide ( 4 ) on hyaluronan synthase (HAS) gene expression in TNF-α/IFN-γ–stimulated human epidermal keratinocytes (HEKs). Cells were pretreated with mandelamide at the indicated concentrations (12.5, 25, 50, and 100 μM) for 1 h, followed by stimulation with TNF-α/IFN-γ for 24 h. The mRNA expression levels of HAS-1, HAS-2, and HAS-3 were quantified by quantitative real-time PCR (qRT-PCR). All experiments were performed according to the manufacturers’ protocols. Data are presented as mean ± SEM ( n = 3). Statistical significance was determined using one-way ANOVA followed by Tukey’s multiple comparisons test; ## p < 0.05 and ### p < 0.001 vs. control; *, **, and *** p < 0.05, p < 0.01, and p < 0.001 vs. TNF-α/IFN-γ–treated group.

Article Snippet: Human dermal fibroblasts (HDFs; CAT No. C-12302, adult donor) and human epidermal keratinocytes (HEKs; CAT No. C-12006, pooled adult donor) were purchased from PromoCell GmbH (Heidelberg, Germany).

Techniques: Gene Expression, Expressing, Real-time Polymerase Chain Reaction, Quantitative RT-PCR, Control