scholarly journals Investigation of the interaction of keratinocytes and Candida species

2021 ◽  
Vol 3 (12) ◽  
Author(s):  
Novák Ádám ◽  
Zajta Erik ◽  
Csikós Máté ◽  
Vágvölgyi Csaba ◽  
Gácser Attila

Our skin provides immunological protection against several pathogens. Skin epithelial cells respond to microbial stimuli in various ways, such as through the production of antimicrobial peptides or secretion of cytokines, although phagocytosis of potentially evading microbes was also reported. Relatively little is known about how skin keratinocytes differentiate between the presence of pathogenic and commensal fungi. In this project, we aimed to investigate how human keratinocytes interact with different Candida species, as common colonizers of the skin. While C. albicans is a common cause of cutaneous candidiasis, C. parapsilosisis rarely associated with this disease.For the experimentshuman skin keratinocyte cell lines (HaCaT, HPV-KER)were applied andchallengedwith C. albicans (SC5314 and WO1 strains) and C. parapsilosis (GA1 and CLIB214 strains)strains.We aimedto determine the extent to which C. albicans and C. parapsilosis damage human keratinocytes, their attachment to host cells, the keratinocytes’ ability to internalize these fungi and to examinecytokine production in response to stimuli. Our results suggest that C. albicans causes significantly more damage to human keratinocytes than C. parapsilosis and the HPV-KER cell line was more susceptibleto the infection. In both HaCaT and HPV-KER cells, the production of IL-6, IL-8, and CCL5 increased primarilyafter C. albicans infection. Based on the adhesion studies, there was a low degree of association in case of C. parapsilosis GA1 and CLIB214 compared to C. albicans SC5314 and WO1.

Author(s):  
Douglas R. Keene ◽  
Gregory P. Lunstrum ◽  
Patricia Rousselle ◽  
Robert E. Burgeson

A mouse monoclonal antibody produced from collagenase digests of human amnion was used by LM and TEM to study the distribution and ultrastructural features of an antigen present in epithelial tissues and in cultured human keratinocytes, and by immunoaffinity chromatography to partially purify the antigen from keratinocyte cell culture media.By immunofluorescence microscopy, the antigen displays a tissue distribution similar to type VII collagen; positive staining of the epithelial basement membrane is seen in skin, oral mucosa, trachea, esophagus, cornea, amnion and lung. Images from rotary shadowed preparations isolated by affinity chromatography demonstrate a population of rod-like molecules 107 nm in length, having pronounced globular domains at each end. Polyacrylamide gel electrophoresis suggests that the size of this molecule is approximately 440kDa, and that it is composed of three nonidentical chains disulfide bonded together.


2013 ◽  
Vol 4 (4) ◽  
pp. 290-298
Author(s):  
Elainy Martins Oliveira ◽  
Waldesse Oliveira Junior ◽  
Jaqueline Oliveira ◽  
Henrique Guilhon De Castro

Ageratum conyzoides (Asteraceae) is known in Brazil for its medicinal properties being mainly used as painkiller and anti-inflammatory. Due to the existence of few genetic studies for this species, this work aimed to characterize the genetic diversity among nine accessions from different sites at Tocantins state, to provide information about its genetic resources. Similarity coefficients obtained varied from 48% to 80%, result of amplification of 102 fragments, of which 72 (70.5%) were polymorphic. Groupment analysis allowed the differentiation in three groups. One of them was distinguished because it presented the highest similarity among all, being composed by ANA and NAT (80% similarity). In general, these data showed there is low degree of association between the geographic location of the accessions and the genetic distances. So, the collected accession ns in Tocantins state presented considerable genetic variability and the efficiency of RAPD markers for such characterization was here proven.


2021 ◽  
Vol 12 ◽  
Author(s):  
Pasquale Filannino ◽  
Raffaella Di Cagno ◽  
Olimpia Vincentini ◽  
Daniela Pinto ◽  
Andrea Polo ◽  
...  

We compared raw bee-collected pollen (Raw-BCP), spontaneously fermented BCP (Unstarted-BCP), and BCP fermented with selected microbial starters (Started-BCP) to deepen whether fermentation may favorably affect the nutrients bioaccessibility and functional features of BCP. Under in vitro gastrointestinal batches, the highest serum-availability of phenolic compounds was found in Started-BCP, highlighting the positive effect exerted by selected microbial starters. The same effect was not found in spontaneously fermented BCP. In colon adenocarcinoma cell line-2 (Caco-2) cells stressed by a pro-inflammatory stimulus, the treatment with Started-BCP halted the increase of pro-inflammatory mediator’s level. Started-BCP counteracted efficiently the deleterious effects of inflammatory stimuli on the integrity of the Caco-2 cells monolayer and its barrier function. Started-BCP successfully counteracted the H2O2-induced intracellular accumulation of reactive oxygen species (ROS) in Caco-2 cells. A protective role against lipopolysaccharide (LPS)-induced inflammation was exerted by Started-BCP in human keratinocytes. The same protective effects on Caco-2 and keratinocyte cell lines were negligible after treatments with Raw-BCP or Unstarted-BCP.


2016 ◽  
Vol 10 (2) ◽  
Author(s):  
Zeinab Ghasemi ◽  
Seyed Jamale Hashemi ◽  
Sassan Rezaei ◽  
Parivash Kordbache ◽  
Mojtaba Khosravi ◽  
...  

Author(s):  
Golnar Sadeghi ◽  
Mina Ebrahimi-Rad ◽  
Masoomeh Shams-Ghahfarokhi ◽  
Zahra Jahanshiri ◽  
Esmat Mirabzadeh Ardakani ◽  
...  

Background and Objectives: Cutaneous candidiasis is a multipicture fungal infection caused by members of the genus Candida which is considered as a public health problem all over the world with urgency of effective treatment and control. This study was performed to analyze the clinical epidemiology and molecular aspects of cutaneous candidiasis in Tehran-Iran in relation to antifungal susceptibility and virulence factors of etiologic Candida species. Materials and Methods: Candida species were isolated from skin (27.3%) and nail scrapings (72.7%) of suspected patients and identified by ITS sequencing. Phylogeny of the isolates was evaluated using multilocus sequence typing (MLST) and antifungal susceptibility and virulence factors of the isolates were determined in relation to clinical presentation. Results: Candida albicans was the most prevalent species (39.8%), followed by C. parapsilosis (32.9%), C. orthopsilosis (10.4%), C. tropicalis (7.9%), C. glabrata and C. guilliermondii, each (4.5%). Molecular typing of 35 C. albicans isolates by MLST revealed 28 novel sequence types with 11 singletons with 80.0% new diploid sequence types (DSTs). Majority of the isolates were susceptible to amphotericin B (91.5%), followed by posaconazole (90.3%), fluconazole (84.3%), itraconazole (74.1%), caspofungin (53.6%), and voriconazole (26.8%). Biofilm formation, yeast-to-hyphae transformation and phospho- lipase activity were reported species-dependent. Conclusion: Our results demonstrated clinical epidemiology of various Candida species from cutaneous candidiasis dis- tributed in new molecular types with increasing importance of drug resistant of non-albicans Candida species. Our results showed that drug susceptibility and genetic variability of Candida species may be attributed to their clinical features and source of isolation.


2004 ◽  
Vol 72 (10) ◽  
pp. 5668-5675 ◽  
Author(s):  
Sompid Kintarak ◽  
Simon A. Whawell ◽  
Paul M. Speight ◽  
Samantha Packer ◽  
Sean P. Nair

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.


2018 ◽  
Vol 39 (1) ◽  
Author(s):  
Sachini U. Siriwardena ◽  
Madusha L. W. Perera ◽  
Vimukthi Senevirathne ◽  
Jessica Stewart ◽  
Ashok S. Bhagwat

ABSTRACTPhorbol 12-myristate 13-acetate (PMA) promotes skin cancer in rodents. The mutations found in murine tumors are similar to those found in human skin cancers, and PMA promotes proliferation of human skin cells. PMA treatment of human keratinocytes increases the synthesis of APOBEC3A, an enzyme that converts cytosines in single-stranded DNA to uracil, and mutations in a variety of human cancers are attributed to APOBEC3A or APOBEC3B expression. We tested here the possibility that induction of APOBEC3A by PMA causes genomic accumulation of uracils that may lead to such mutations. When a human keratinocyte cell line was treated with PMA, both APOBEC3A and APOBEC3B gene expression increased, anti-APOBEC3A/APOBEC3B antibody bound a protein(s) in the nucleus, and nuclear extracts displayed cytosine deamination activity. Surprisingly, there was little increase in genomic uracils in PMA-treated wild-type or uracil repair-defective cells. In contrast, cells transfected with a plasmid expressing APOBEC3A acquired more genomic uracils. Unexpectedly, PMA treatment, but not APOBEC3A plasmid transfection, caused a cessation in cell growth. Hence, a reduction in single-stranded DNA at replication forks may explain the inability of PMA-induced APOBEC3A/APOBEC3B to increase genomic uracils. These results suggest that the proinflammatory PMA is unlikely to promote extensive APOBEC3A/APOBEC3B-mediated cytosine deaminations in human keratinocytes.


2015 ◽  
Vol 36 (5) ◽  
pp. 1890-1902 ◽  
Author(s):  
Yanfei Zhang ◽  
Chen Tu ◽  
Dingwei Zhang ◽  
Yan Zheng ◽  
Zhenhui Peng ◽  
...  

Background/Aims: Wnt5a is overexpressed in psoriasis lesions, however the mechanism by which Wnt5a is involved in the pathogenesis of psoriasis is not clear. To address this, the expression of Wnt5a in psoriatic lesions and its effect on keratinocyte cell proliferation and apoptosis was examined in vitro. Methods: The expression levels of WNT5A, and genes encoding its receptors frizzled2 (FZD2) and frizzled5 (FZD5) were examined in samples obtained from individuals with psoriasis and healthy controls. Knockdown of Wnt5a with short interfering (si)RNAs was performed in cultured HaCaT keratinocytes and normal human keratinocytes (NHK), and the expression of Wnt5a, protein kinase C (PKC), and β-catenin were determined, and cell cycle activity, proliferation and apoptosis were assessed. Results: The expression of WNT5A, FZD2 and FZD5 mRNA and protein were increased in psoriatic lesions. Wnt5a knockdown suppressed proliferation and induced apoptosis in HaCaT and NHK cells. Additionally, expression of PCNA, MKI67, CCND1, BCL2, CTNNB1, and genes encoding PKC and survivin were downregulated, whereas CASP3 was upregulated. The mRNA levels of the Wnt pathway inhibitors DKK1 and SFRP1 were upregulated, Western blotting analyses demonstrated reduction in β-catenin and PKC protein levels. Conclusion: Knockdown of Wnt5a suppresses the proliferation of keratinocytes and induces apoptosis by inhibiting the Wnt/β-catenin or Wnt5a/Ca2+ pathways.


2017 ◽  
Vol 4 (suppl_1) ◽  
pp. S87-S87
Author(s):  
Celestine Ishiekwene ◽  
Maxine Seales Kasangana ◽  
Monica Ghitan ◽  
Margaret Kuhn-Basti ◽  
Edward Chapnick ◽  
...  

Abstract Background Candida remains the most common cause of invasive fungal infections, with an attributable morality of 15–35%. Although five Candida species (C. albicans, C. tropicalis, C. parapsilosis, C. glabrata, and C. krusei) account for 92% of cases of candidemia, Candida albicans remains the most common cause of candidemia. However, recent studies report that the frequency of non albicans species are increasing globally and the distribution of Candida spp. varies significantly among different geographic regions and hospitals units. Objective We determine the distribution of Candida species causing candidemia at an adult level 1 Trauma Center in Brooklyn, New York and compared the trends of Candida species between 2005 and 2014. The results were compared with trends of US data collected in 2004 and 2012. Knowledge of the frequency of causative species would facilitate appropriate selection of empiric antifungal therapy. Methods We performed a retrospective chart review of patients with candidemia who were admitted in 2005 and 2014. We determined the frequency of Candida species and compared 2005 data with those in 2014. Results In total, 226 and 109 patients with candidemia were admitted to our hospital in 2005 and 2014, respectively. Although, C. albicans was the most common species (43% of candidemia in 2005), its frequency decreased to 33% in 2014. The frequencies of C. glabrata and C. parapsilosis increased in 2014 compared with those in 2005 (24% vs. 16% and 33% vs. 26%, respectively). Figure 1 compared the proportion of Candida species in Maimonides Medical Center to National data. Conclusion Our finding of an increase in non-albicans spp. causing candidemia is consistent with published reports. We saw more cases of C. parapsilosis compared with published data. Our results may be used to inform empiric antifungal therapy. Disclosures All authors: No reported disclosures.


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