The interaction of sperm with the oocyte is pivotal during the process of mammalian fertilization. The limited numbers of sperm that reach the fallopian tube as well as anatomic restrictions indicate ...that human sperm–oocyte encounter is not a matter of chance but a directed process. Chemotaxis is the proposed mechanism for re-orientating sperm toward the source of a chemoattractant and hence to the oocyte. Chemokines represent a superfamily of small (8–11 kDa), cytokine-like proteins that have been shown to mediate chemotaxis and tissue-specific homing of leukocytes through binding to specific chemokine receptors such as CCRs. Here we show that CCR6 is abundantly expressed on human sperms and in human testes. Furthermore, radioligand-binding experiments showed that CCL20 bound human sperm in a specific manner. Conversely, granulosa cells of the oocyte-surrounding cumulus complex as well as human oocytes represent an abundant source of the CCR6-specific ligand CCL20. In human ovaries, CCL20 shows a cycle-dependent expression pattern with peak expression in the preovulatory phase and CCL20 protein induces chemotactic responses of human sperm. Neutralization of CCL20 in ovarian follicular fluid significantly impairs sperm migratory responses. Conversely, analyses in infertile men with inflammatory conditions of the reproductive organs demonstrate a significant increase of CCL20/CCR6 expression in testis and ejaculate. Taken together, findings of the present study suggest that CCR6-CCL20 interaction may represent an important factor in directing sperm–oocyte interaction. Graphical Abstract Summary Sentence The chemokine CCL20 is produced by human oocytes as well as surrounding cumulus granulosa cells and induces chemotaxis of CCR6+ sperm. Infertile male donors demonstrate increased levels of CCL20 in testis and seminal fluid, which may negatively influence sperm–oocyte interaction.
Aims: To determine the incidence of antimicrobial‐resistant Salmonella spp. on processed poultry (turkey) at Midwestern poultry plants.
Methods and Results: Two participating plants were visited at ...monthly intervals for a period of 1 year. Surface swabs were obtained from carcasses at two selected points on the production line, pre‐ and post‐chill. In addition, samples of the chill water from chill tanks were also examined. Isolation and detection of Salmonella spp. from carcass swabs and chill water was carried out using standard enrichment techniques. Immunomagnetic separation was used to enhance the recovery of the pathogen. Salmonella isolates recovered were identified, serotyped and their antimicrobial resistance profiles determined using the National Antimicrobial Resistance Monitoring System. Results from the study indicated that the overall incidence of Salmonella was approx. 16·7%, with a greater incidence of the pathogen observed on pre‐chill than post‐chill carcasses. Salmonella isolates recovered displayed resistance to an average of four different antimicrobials. Approximately 15 different serotypes of Salmonella spp. were recovered, with Salmonella serotype Agona, Salmonella serotype Hadar, Salmonella serotype Heidelberg and Salmonella serotype Senftenberg being the most common.
Conclusions: The incidence of Salmonella spp. was relatively low and isolates recovered showed significant degrees of antimicrobial resistance. Factors such as the processing plant examined, the season and farms that were presenting animals for processing influenced the incidence of the pathogen.
Significance and Impact of the Study: Differences were observed in the serotypes of Salmonella recovered and the types of antimicrobial resistance found at the two plants. The study suggests that the use of antimicrobials at the farm level influences the creation of an environment that promotes the selection of antimicrobial‐resistant Salmonella spp. The incidence, isolation and detection of Salmonella spp. on processed poultry are discussed.
Aim: The primary aim of this study was to determine the incidence of Campylobacter spp. on turkey, presented for processing at participating production plants located in the midwest region of the ...United States.
Methods and Results: The two participating plants were visited on a monthly basis for a period of 1 year. Sampling of carcasses was carried out using a surface swab technique. Swabs were obtained from carcasses at two points on the production line – prechill and postchill. In addition, samples of chill water were also obtained for examination. Isolation and detection of Campylobacter was carried out using enrichment in Preston broth with recovery of the organism on blood free Campylobacter selective agar (CCDA). Isolates recovered were screened and identified using the API Campy® identification system. The study found that 34·9% of all samples tested were positive for Campylobacter spp. The overall, contamination rates observed for both plants were relatively similar (39·2% for plant A and 30·6% for plant B). Differences were observed in the incidence of Campylobacter spp. on prechill vs postchill carcasses (i.e. 40·8% prechill vs 37·6% postchill for plant A and 41·8% prechill vs 19·8% postchill for plant B). Campylobacter species most often isolated included Camp. jejuni and Camp. coli. Other species recovered were Camp. fetus fetus, Camp. upsaliensis and Camp. lari.
Conclusions: The incidence of Campylobacter spp. on processed poultry was relatively common. Factors such as the processing plant examined, season and the farms presenting birds for processing influenced the incidence of the pathogen.
Significance and Impact of the Study: Differences were observed in the prevalence of Campylobacter spp. isolated from the two plants examined. The study suggests a seasonal prevalence of Campylobacter in the cooler months with processing conditions also influencing the overall occurrence of the organism. The incidence, isolation and detection of Campylobacter spp. from processed poultry are discussed.
The relationship of retinoid and carotenoid metabolism with caecotrophy was studied in adult female New Zealand White rabbits kept in individual metabolic cages. Caecotrophy was prevented by the use ...of plastic collars. The dry matter, crude protein, fibre, fat and ash contents of hard and soft faecal samples were determined. The retinoid (retinol and retinyl palmitate) and carotenoid (canthaxanthin, β-carotene, β-cryptoxanthin, lutein and zeaxanthin) levels of the blood, liver, kidney, caecal content and faeces were also measured by high-performance liquid chromatography (HPLC). The prevention of caecotrophy resulted in a significant decrease of blood retinol (P < 0.001) and retinyl palmitate (P < 0.01) concentration but it did not cause any significant change in the retinol and retinyl palmitate contents of the liver and kidney. The caecal content (25.78 ± 6.87 µg/g) and the soft faeces (34.52 ± 10.48 µg/g) contained the retinoids in similar amounts. Various carotenoids were found in considerable amounts in different types of faeces, while in the tissues (blood, liver and kidney) these pigments did not occur in substantial amounts. Total carotenoid concentration was similar in the caecal content (11.23 μg/g) and in the caecotroph (13.85 μg/g). On the basis of the results it can be assumed that the retinoid content of rabbit feed could be lowered in the presence of adequate caecal function and caecotrophy.
The activation of the EGFR/Ras-signalling pathway in tumour cells induces a distinct chemokine repertoire, which in turn modulates the tumour microenvironment.
The effects of EGFR/Ras on the ...expression and translation of CCL20 were analysed in a large set of epithelial cancer cell lines and tumour tissues by RT-qPCR and ELISA in vitro. CCL20 production was verified by immunohistochemistry in different tumour tissues and correlated with clinical data. The effects of CCL20 on endothelial cell migration and tumour-associated vascularisation were comprehensively analysed with chemotaxis assays in vitro and in CCR6-deficient mice in vivo.
Tumours facilitate progression by the EGFR/Ras-induced production of CCL20. Expression of the chemokine CCL20 in tumours correlates with advanced tumour stage, increased lymph node metastasis and decreased survival in patients. Microvascular endothelial cells abundantly express the specific CCL20 receptor CCR6. CCR6 signalling in endothelial cells induces angiogenesis. CCR6-deficient mice show significantly decreased tumour growth and tumour-associated vascularisation. The observed phenotype is dependent on CCR6 deficiency in stromal cells but not within the immune system.
We propose that the chemokine axis CCL20-CCR6 represents a novel and promising target to interfere with the tumour microenvironment, and opens an innovative multimodal strategy for cancer therapy.
Despite recent advances in understanding microbial diversity in skin homeostasis, the relevance of microbial dysbiosis in inflammatory disease is poorly understood. Here we perform a comparative ...analysis of skin microbial communities coupled to global patterns of cutaneous gene expression in patients with atopic dermatitis or psoriasis. The skin microbiota is analysed by 16S amplicon or whole genome sequencing and the skin transcriptome by microarrays, followed by integration of the data layers. We find that atopic dermatitis and psoriasis can be classified by distinct microbes, which differ from healthy volunteers microbiome composition. Atopic dermatitis is dominated by a single microbe (Staphylococcus aureus), and associated with a disease relevant host transcriptomic signature enriched for skin barrier function, tryptophan metabolism and immune activation. In contrast, psoriasis is characterized by co-occurring communities of microbes with weak associations with disease related gene expression. Our work provides a basis for biomarker discovery and targeted therapies in skin dysbiosis.
Background
Atopic dermatitis (AD) is a frequent and heterogeneous inflammatory skin disease, for which personalized medicine remains a challenge. High‐throughput approaches have improved ...understanding of the complex pathophysiology of AD. However, a purely data‐driven AD classification is still lacking.
Methods
To address this question, we applied an original unsupervised approach on the largest available transcriptome dataset of AD lesional (n = 82) and healthy (n = 213) skin biopsies.
Results
Taking into account pathological and physiological state, a variance‐based filtering revealed 222 AD‐specific hyper‐variable genes that efficiently classified the AD samples into 4 clusters that turned out to be clinically and biologically distinct. Comparison of gene expressions between clusters identified 3 sets of upregulated genes used to derive metagenes (MGs): MG‐I (19 genes) was associated with IL‐1 family signaling (including IL‐36A and 36G) and skin remodeling, MG‐II (23 genes) with negative immune regulation (including IL‐34 and 37) and skin architecture, and MG‐III (17 genes) with B lymphocyte immunity. Sample clusters differed in terms of disease severity (p = .02) and S. aureus (SA) colonization (p = .02). Cluster 1 contained the most severe AD, highest SA colonization, and overexpressed MG‐I. Cluster 2 was characterized by less severe AD, low SA colonization, and high MG‐II expression. Cluster 3 included mild AD, mild SA colonization, and mild expression of all MGs. Cluster 4 had the same clinical features as cluster 3 but had hyper‐expression of MG‐III. Last, we successfully validated our method and results in an independent cohort.
Conclusion
Our study revealed unrecognized AD endotypes with specific underlying biological pathways, highlighting novel pathophysiological mechanisms. These data could provide new insights into personalized treatment strategies.
We used the largest skin transcriptome cohort including 82 AD patients and 213 healthy control biopsies. We applied a variance‐based gene selection of AD‐specific hypervariable genes to reveal disease heterogeneity. These genes were used for the unsupervised clustering into 4 AD endotypes characterized by distinct biological and clinical features, revealing the duality between pro‐ and anti‐inflammatory mechanisms. Abbreviations: AD, atopic dermatitis; S. aureus, Staphylococcus aureus; SCORAD, scoring atopic dermatitis.
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