Interferon-Lambda 1 Inhibits Staphylococcus aureus Colonization in Human Primary Keratinocytes

Atopic dermatitis (AD) is a common inflammatory skin disease. Staphylococcus aureus (S. aureus) colonization in skin lesions occurs in approximately 70% of AD patients. It has been found that IFN-λ1 can inhibit the colonization of S. aureus in normal human nasal mucosa. IFN-λ1 can increase IL-28RA in infected human keratinocytes. In this study, we found that IFN-λ1 can increase mRNA expression of FLG and antimicrobial peptides (AMPs) and inhibit TSLP mRNA expression in infected human keratinocytes. IFN-λ1 can increase intracellular ROS level, decrease STAT1 phosphorylation, and inhibit the colonization of S. aureus in human primary keratinocytes. These effects were attenuated by knocking-down IL-28R and NADPH oxidase inhibitor, suggesting that this function was mediated by JAK-STAT1 signaling pathway. These results suggest that IFN-λ1 might have an inhibitory effect on S. aureus colonization in AD lesions. Our findings might have potential value in the treatment for AD.

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Effect of silver nanoparticles on human primary keratinocytes

Biological Chemistry ◽

10.1515/hsz-2012-0202 ◽

2013 ◽

Vol 394 (1) ◽

pp. 113-123 ◽

Cited By ~ 15

Author(s):

Radoslaw Szmyd ◽

Anna Grazyna Goralczyk ◽

Lukasz Skalniak ◽

Agnieszka Cierniak ◽

Barbara Lipert ◽

...

Keyword(s):

Silver Nanoparticles ◽

Chemical Properties ◽

Wound Dressings ◽

Epidermal Keratinocytes ◽

Primary Keratinocytes ◽

Human Epidermal Keratinocytes ◽

Normal Human ◽

Physical And Chemical ◽

First Time ◽

Human Primary Keratinocytes

Abstract Silver nanoparticles (AgNPs) have many biological applications in biomedicine, biotechnology and other life sciences. Depending on the size, shape and the type of carrier, AgNPs demonstrate different physical and chemical properties. AgNPs have strong antimicrobial, antiviral and antifungal activity, thus they are used extensively in a range of medical settings, particularly in wound dressings but also in cosmetics. This study was undertaken to examine the potential toxic effects of 15 nm polyvinylpyrrolidone-coated AgNPs on primary normal human epidermal keratinocytes (NHEK). Cells were treated with different concentrations of AgNPs and then cell viability, metabolic activity and other biological and biochemical aspects of keratinocytes functioning were studied. We observed that AgNPs decrease keratinocyte viability, metabolism and also proliferatory and migratory potential of these cells. Moreover, longer exposure resulted in activation of caspase 3/7 and DNA damage. Our studies show for the first time, that AgNPs may present possible danger for primary keratinocytes, concerning activation of genotoxic and cytotoxic processes depending on the concentration.

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Apoptosis is not required for acantholysis in pemphigus vulgaris

AJP Cell Physiology ◽

10.1152/ajpcell.00161.2008 ◽

2009 ◽

Vol 296 (1) ◽

pp. C162-C172 ◽

Cited By ~ 32

Author(s):

Enno Schmidt ◽

Judith Gutberlet ◽

Daniela Siegmund ◽

Daniela Berg ◽

Harald Wajant ◽

...

Keyword(s):

Caspase 3 ◽

Pemphigus Vulgaris ◽

Human Keratinocytes ◽

Skin Lesions ◽

Terminal Deoxynucleotidyl Transferase ◽

Epidermal Keratinocytes ◽

Death Domain ◽

Human Epidermal Keratinocytes ◽

Desmosomal Cadherins ◽

Normal Human

The autoimmune blistering skin disease pemphigus vulgaris (PV) is caused primarily by autoantibodies against desmosomal cadherins. It was reported that apoptosis can be detected in pemphigus skin lesions and that apoptosis can be induced by PV-IgG in cultured keratinocytes. However, the role of apoptosis in PV pathogenesis is unclear at present. In this study, we provide evidence that apoptosis is not required for acantholysis in PV. In skin lesions from two PV patients, terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) positivity, but not cleaved caspase-3, was detected in single keratinocytes in some lesions but was completely absent in other lesions from the same patients. In cultures of human keratinocytes (HaCaT and normal human epidermal keratinocytes), PV-IgG from three different PV patients caused acantholysis, fragmented staining of Dsg 3 staining, and cytokeratin retraction in the absence of nuclear fragmentation, TUNEL positivity, and caspase-3 cleavage and hence in the absence of detectable apoptosis. To further rule out the contribution of apoptotic mechanisms, we used two different approaches that are effective to block apoptosis induced by various stimuli. Inhibition of caspases by z-VAD-fmk as well as overexpression of Fas-associated death domain-like interleukin-1β-converting enzyme (FLICE)-like inhibitory proteins FLIPL and FLIPS to inhibit receptor-mediated apoptosis did not block PV-IgG-induced effects, indicating that apoptosis was not required. Taken together, we conclude that apoptosis is not a prerequisite for skin blistering in PV but may occur secondary to acantholysis.

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Internalization of Staphylococcus aureus by Human Keratinocytes

Infection and Immunity ◽

10.1128/iai.72.10.5668-5675.2004 ◽

2004 ◽

Vol 72 (10) ◽

pp. 5668-5675 ◽

Cited By ~ 75

Author(s):

Sompid Kintarak ◽

Simon A. Whawell ◽

Paul M. Speight ◽

Samantha Packer ◽

Sean P. Nair

Keyword(s):

Staphylococcus Aureus ◽

Human Keratinocytes ◽

Host Cells ◽

Human Pathogens ◽

Chronic Infections ◽

Primary Keratinocytes ◽

Bacterial Uptake ◽

Fibronectin Binding ◽

Isogenic Mutants ◽

Systemic Infections

ABSTRACT Staphylococcus aureus is among the most important human pathogens and causes various superficial and systemic infections. The ability of S. aureus to be internalized by, and survive within, host cells, such as keratinocytes, may contribute to the development of persistent or chronic infections and may finally lead to deeper tissue infections or dissemination. To examine the mechanisms of internalization of S. aureus by keratinocytes, isogenic mutants lacking fibronectin-binding proteins (FnBPs), a recombinant protein consisting of the fibronectin-binding domain of S. aureus FnBPs, and an anti-α5β1 antibody were used in cocultures with immortalized keratinocytes and primary keratinocytes. We found that internalization of S. aureus by immortalized keratinocytes requires bacterial FnBPs and is mediated by the major fibronectin-binding integrin α5β1. In contrast to internalization by immortalized keratinocytes, internalization of S. aureus by primary keratinocytes could occur through FnBP-dependent and -independent pathways. S. aureus clumping factor B (ClfB), which was recently determined to bind to epithelial cells, was not involved in the uptake of this bacterium by keratinocytes. The identification of an alternate uptake pathway, which is independent of S. aureus FnBPs and host cell α5β1, has important implications for the design of therapies targeted to bacterial uptake by host cells.

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Plasma exosomal miR-375-3p regulates mitochondria-dependent keratinocyte apoptosis by targeting XIAP in severe drug-induced skin reactions

Science Translational Medicine ◽

10.1126/scitranslmed.aaw6142 ◽

2020 ◽

Vol 12 (574) ◽

pp. eaaw6142

Author(s):

Chen Zhang ◽

ZhenLai Zhu ◽

JiXin Gao ◽

LuTing Yang ◽

ErLe Dang ◽

...

Keyword(s):

Human Keratinocytes ◽

Clinical Severity ◽

Stevens Johnson Syndrome ◽

Primary Keratinocytes ◽

Primary Human Keratinocytes ◽

Drug Induced ◽

Skin Reactions ◽

Apoptosis Protein ◽

Human Primary Keratinocytes

Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe drug-induced cutaneous reactions characterized by keratinocyte apoptosis. Exosomes are nanometer-sized membranous vesicles in body fluids. They contain functional proteins, mRNAs, and miRNAs, which induce immune dysfunction and influence disease progression. However, their roles and mechanisms in SJS/TEN remain unknown. Our results demonstrate that exosomes isolated from the plasma of patients with SJS/TEN were 30 to 200 nm in diameter and expressed CD9, CD63, CD81, and TSG101 exosome marker proteins. miR-375-3p was markedly up-regulated in 35 patients with SJS/TEN and correlated with clinical severity. Plasma exosomes were internalized by human primary keratinocytes and promoted keratinocyte apoptosis in vitro. Furthermore, miR-375-3p overexpression promoted intrinsic (mitochondria-dependent) apoptosis of human primary keratinocytes via down-regulation of the X-linked inhibitor of apoptosis protein (XIAP), a key apoptosis regulator in primary human keratinocytes. In sum, our study indicates that the circulating exosomal miR-375-3p enters keratinocytes, down-regulates XIAP, and induces keratinocyte apoptosis in patients with SJS/TEN.

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