Psoriatic lesions are characterized by higher bacterial load and imbalance between Cutibacterium and Corynebacterium.

BACKGROUND: Several studies have found that the microbiota of psoriatic lesions is different from that of healthy skin. OBJECTIVE: To characterize the microbiota of lesional and unaffected skin in patients with psoriasis and controls and investigate the correlation between cutaneous microbiota and clinical features of psoriasis. METHODS: Using quantitative polymerase chain reaction and 16S rRNA sequencing, we assayed the profiles of cutaneous microbiota in controls, unaffected skin, and psoriatic lesions. We also investigated the correlation of psoriasis-associated taxa with clinical characteristics. RESULTS: High bacterial load was identified in the psoriatic lesions compared with unaffected skin and controls. There was an imbalance between Cutibacterium (also known as Propionibacterium) and Corynebacterium in psoriatic skin. Lesions showed a higher proportion of Corynebacterium and a lower proportion of Cutibacterium compared with unaffected skin and controls. Corynebacterium was correlated with the severity of local lesions, whereas Cutibacterium showed correlation with the abnormity of skin capacitance. LIMITATIONS: We did not conduct a longitudinal study. CONCLUSIONS: Psoriatic lesions are characterized by higher bacterial load and imbalance between Cutibacterium and Corynebacterium.

Cytokine Levels in the In Vitro Response of T Cells to Planktonic and Biofilm Corynebacterium amycolatum.

Unravelling of the interplay between the immune system and non-diphtheria corynebacteria would contribute to understanding their increasing role as medically important microorganisms. We aimed at the analysis of pro- (TNF, IL-1ß, IL-6, IL-8, and IL-12p70) and anti-inflammatory (IL-10) cytokines produced by Jurkat T cells in response to planktonic and biofilm Corynebacterium amycolatum. Two reference strains: C. amycolatum ATCC 700207 (R-CA), Staphylococcus aureus ATCC 25923 (R-SA), and ten clinical strains of C. amycolatum (C-CA) were used in the study. Jurkat T cells were stimulated in vitro by the planktonic-conditioned medium (PCM) and biofilm-conditioned medium (BCM) derived from the relevant cultures of the strains tested. The cytokine concentrations were determined in the cell culture supernatants using the flow cytometry. The levels of the cytokines analyzed were lower after stimulation with the BCM when compared to the PCM derived from the cultures of C-CA; statistical significance (p < 0.05) was observed for IL-1ß, IL-12 p70, and IL-10. Similarly, planktonic R-CA and R-SA stimulated a higher cytokine production than their biofilm counterparts. The highest levels of pro-inflammatory IL-8, IL-1ß, and IL-12p70 were observed after stimulation with planktonic R-SA whereas the strongest stimulation of anti-inflammatory IL-10 was noted for the BCM derived from the mixed culture of both reference species. Our results are indicative of weaker immunostimulatory properties of the biofilm C. amycolatum compared to its planktonic form. It may play a role in the persistence of biofilm-related infections. The extent of the cytokine response can be dependent on the inherent virulence of the infecting microorganism.Unravelling of the interplay between the immune system and non-diphtheria corynebacteria would contribute to understanding their increasing role as medically important microorganisms. We aimed at the analysis of pro- (TNF, IL-1ß, IL-6, IL-8, and IL-12p70) and anti-inflammatory (IL-10) cytokines produced by Jurkat T cells in response to planktonic and biofilm Corynebacterium amycolatum. Two reference strains: C. amycolatum ATCC 700207 (R-CA), Staphylococcus aureus ATCC 25923 (R-SA), and ten clinical strains of C. amycolatum (C-CA) were used in the study. Jurkat T cells were stimulated in vitro by the planktonic-conditioned medium (PCM) and biofilm-conditioned medium (BCM) derived from the relevant cultures of the strains tested. The cytokine concentrations were determined in the cell culture supernatants using the flow cytometry. The levels of the cytokines analyzed were lower after stimulation with the BCM when compared to the PCM derived from the cultures of C-CA; statistical significance (p < 0.05) was observed for IL-1ß, IL-12 p70, and IL-10. Similarly, planktonic R-CA and R-SA stimulated a higher cytokine production than their biofilm counterparts. The highest levels of pro-inflammatory IL-8, IL-1ß, and IL-12p70 were observed after stimulation with planktonic R-SA whereas the strongest stimulation of anti-inflammatory IL-10 was noted for the BCM derived from the mixed culture of both reference species. Our results are indicative of weaker immunostimulatory properties of the biofilm C. amycolatum compared to its planktonic form. It may play a role in the persistence of biofilm-related infections. The extent of the cytokine response can be dependent on the inherent virulence of the infecting microorganism.

Corynebacterium kroppenstedtii in granulomatous mastitis: Analysis of formalin-fixed, paraffin-embedded biopsy specimens by immunostaining using low-specificity bacterial antisera and real-time polymerase chain reaction.

Granulomatous mastitis (GM) is a rare inflammatory disease of the post-lactation breast, clinically mimicking breast cancer. GM is microscopically characterized by formation of epithelioid granulomas and abscess (suppurative granulomas) with lipid droplet-centered inflammation. Corynebacterium kroppenstedtii (Ck) is known as a causative bacterium of GM, and identification of Ck infection within the lesion should thus be essential for confirming the diagnosis. In the present study, we analyzed formalin-fixed, paraffin-embedded (FFPE) biopsy specimens of a total of 18 GM lesions with immunostaining and real-time PCR for Ck genome. Widely cross-reactive rabbit antisera against Bacillus Calmette-Guerin (BCG), Bacillus cereus, Treponema pallidum and Escherichia coli were chosen. With real-time PCR, Ck genome was demonstrated in 7 of 18 GM lesions. Immunohistochemically, the low-specificity antisera reacted with the cytoplasm of phagocytes and/or granuloma-engulfed lipid droplets in 12 of 18 GM lesions. Antigenic positivity was observed in the following order: BCG > B. cereus > T. pallidum > E. coli. Real-time PCR using DNA extracted from FFPE sections was useful but not consistent for identifying the Ck genome in GM, while immunostaining using cross-reactive antisera against four kinds of bacteria was not Ck-specific but was applicable to visualizing bacterial infection within the GM lesions.

Contemporary microbiology and identification of Corynebacteria spp. causing infections in human.

The Corynebacterium is a genus of bacteria of growing clinical importance. Progress in medicine results in growing population of immunocompromised patients and growing number of infections caused by opportunistic pathogens. A new infections caused by new Corynebacterium species and species previously regarded as commensal micro-organisms have been described. Parallel with changes in Corynebacteria infections, the microbiological laboratory diagnostic possibilities are changing. But identification of this group of bacteria to the species level remains difficult. In the paper, we present various manual, semi-automated and automated assays used in clinical laboratories for Corynebacterium identification, such as API Coryne, RapID CB Plus, BBL Crystal Gram Positive ID System, MICRONAUT-RPO, VITEK 2, BD Phoenix System, Sherlock Microbial ID System, MicroSeq Microbial Identification System, Biolog Microbial Identification Systems, MALDI-TOF MS systems, polymerase chain reaction (PCR)-based and sequencing-based assays. The presented assays are based on various properties, like biochemical tests, specific DNA sequences, composition of cellular fatty acids, protein profiles and have specific limitations. SIGNIFICANCE AND IMPACT OF THE STUDY: The number of opportunistic infections caused by Corynebacteria is increasing due to increase in number of immunocompromised patients. New Corynebacterium species and new human infections, caused by this group of bacteria, has been described recently. However, identification of Corynebacteria is still a challenge despite application of sophisticated laboratory methods. In the study we present possibilities and limitations of various commercial systems for identification of Corynebacteria.

Characterization of Demodex musculi Infestation, Associated Comorbidities, and Topographic Distribution in a Mouse Strain with Defective Adaptive Immunity.

A colony of B6.Cg-Rag1tm1Mom Tyrp1B-w Tg(Tcra,Tcrb)9Rest (TRP1/TCR) mice presented with ocular lesions and ulcerative dermatitis. Histopathology, skin scrapes, and fur plucks confirmed the presence of Demodex spp. in all clinically affected and subclinical TRP1/TCR mice examined (n = 48). Pasteurella pneumotropica and Corynebacterium bovis, both opportunistic pathogens, were cultured from the ocular lesions and skin, respectively, and bacteria were observed microscopically in abscesses at various anatomic locations (including retroorbital sites, tympanic bullae, lymph nodes, and reproductive organs) as well as the affected epidermis. The mites were identified as Demodex musculi using the skin fragment digestion technique. Topographic analysis of the skin revealed mites in almost all areas of densely haired skin, indicating a generalized demodecosis. The percentage of infested follicles in 8- to 10-wk-old mice ranged from 0% to 21%, and the number of mites per millimeter of skin ranged from 0 to 3.7. The head, interscapular region, and middorsum had the highest proportions of infested follicles, ranging from 2.3% to 21.1% (median, 4.9%), 2.0% to 16.6% (8.1%), and 0% to 17% (7.6%), respectively. The pinnae and tail skin had few or no mites, with the proportion of follicles infested ranging from 0% to 3.3% (0%) and 0% to 1.4% (0%), respectively. The number of mites per millimeter was strongly correlated with the percentage of infested follicles. After administration of amoxicillin-impregnated feed (0.12%), suppurative infections were eliminated, and the incidence of ulcerative dermatitis was dramatically reduced. We hypothesize that the Rag1-null component of the genotype makes TRP1/TCR mice susceptible to various opportunistic infestations and infections, including Demodex mites, P. pneumotropica, and C. bovis. Therefore, Rag1-null mice may serve as a useful model to study human and canine demodecosis. D. musculi should be ruled out as a contributing factor in immunocompromised mouse strains with dermatologic manifestations.

An Ocular Commensal Protects against Corneal Infection by Driving an Interleukin-17 Response from Mucosal γδ T Cells.

Mucosal sites such as the intestine, oral cavity, nasopharynx, and vagina all have associated commensal flora. The surface of the eye is also a mucosal site, but proof of a living, resident ocular microbiome remains elusive. Here, we used a mouse model of ocular surface disease to reveal that commensals were present in the ocular mucosa and had functional immunological consequences. We isolated one such candidate commensal, Corynebacterium mastitidis, and showed that this organism elicited a commensal-specific interleukin-17 response from γδ T cells in the ocular mucosa that was central to local immunity. The commensal-specific response drove neutrophil recruitment and the release of antimicrobials into the tears and protected the eye from pathogenic Candida albicans or Pseudomonas aeruginosa infection. Our findings provide direct evidence that a resident commensal microbiome exists on the ocular surface and identify the cellular mechanisms underlying its effects on ocular immune homeostasis and host defense.

Toll-Like Receptor 2 and Mincle Cooperatively Sense Corynebacterial Cell Wall Glycolipids.

Nontoxigenic Corynebacterium diphtheriae and Corynebacterium ulcerans cause invasive disease in humans and animals. Host sensing of corynebacteria is largely uncharacterized, albeit the recognition of lipoglycans by Toll-like receptor 2 (TLR2) appears to be important for macrophage activation by corynebacteria. The members of the order Corynebacterineae (e.g., mycobacteria, nocardia, and rhodococci) share a glycolipid-rich cell wall dominated by mycolic acids (termed corynomycolic acids in corynebacteria). The mycolic acid-containing cord factor of mycobacteria, trehalose dimycolate, activates the C-type lectin receptor (CLR) Mincle. Here, we show that glycolipid extracts from the cell walls of several pathogenic and nonpathogenic Corynebacterium strains directly bound to recombinant Mincle in vitro Macrophages deficient in Mincle or its adapter protein Fc receptor gamma chain (FcRγ) produced severely reduced amounts of granulocyte colony-stimulating factor (G-CSF) and of nitric oxide (NO) upon challenge with corynebacterial glycolipids. Consistently, cell wall extracts of a particular C. diphtheriae strain (DSM43989) lacking mycolic acid esters neither bound Mincle nor activated macrophages. Furthermore, TLR2 but not TLR4 was critical for sensing of cell wall extracts and whole corynebacteria. The upregulation of Mincle expression upon encountering corynebacteria required TLR2. Thus, macrophage activation by the corynebacterial cell wall relies on TLR2-driven robust Mincle expression and the cooperative action of both receptors.

Toxigenic Corynebacterium ulcerans isolated from a hunting dog and its diphtheria toxin antibody titer.

Toxigenic Corynebacterium ulcerans is a zoonotic pathogen that produces diphtheria toxin and causes a diphtheria-like illness in humans. The organism is known to infect and circulate among dogs, which can then transmit it to humans. Furthermore, previous studies have found that C. ulcerans is carried by wild animals, including game animals. In the present study, we tested hunting and companion dogs for the presence of toxigenic C. ulcerans and succeeded in isolating the bacterium from a hunting dog. Moreover, several hunting dogs had serum diphtheria antitoxin titers that were higher than the titers required for protection in humans, suggesting a history of exposure to toxigenic Corynebacterium strains. Notably, ribotyping, pulsed-field gel electrophoresis and tox gene sequencing demonstrated that the isolate from the hunting dog clustered with previously characterized C. ulcerans strains isolated from wild animals, as opposed to groups of isolates from humans and companion dogs. Interestingly, the wild animal cluster also contains an isolate from an outdoor breeding dog, which could have formed a bridge between isolates from wild animals and those from companion dogs. The results presented herein provide insight into the mechanism by which the zoonotic pathogen C. ulcerans circulates among wild animals, hunting and companion dogs, and humans.

A novel experimental platform for toxigenic and non-toxigenic Corynebacterium ulcerans infection in mice.

Corynebacterium ulcerans is a zoonotic pathogen that can produce diphtheria toxin and causes an illness categorized as diphtheria in the European Union because its clinical appearance is similar to that of diphtheria caused by Corynebacterium diphtheriae. Despite the importance of the pathogen in public health, the organism's mechanism of infection has not been extensively studied, especially in experimental animal models. Therefore in the present study we constructed an intranasal infection system for mice. Mice are insensitive to diphtheria toxin and this has the advantage of excluding the cytotoxic effect of the toxin that might interfere with the analysis of the early stage of infection. Both the toxigenic and non-toxigenic C. ulcerans strains were capable of killing mice within 3 days after inoculation at 10(7) colony-forming units per mouse. In experimentally infected animals, C. ulcerans was detected in the respiratory tract but not in the intestinal tract. The bacterium was also detected in peripheral blood and it disseminated into the lung, kidney and spleen to produce a systemic infection. This experimental infection system provides a platform for analyzing the virulence of C. ulcerans in future studies.

The killing of macrophages by Corynebacterium ulcerans.

Corynebacterium ulcerans is an emerging pathogen transmitted by a zoonotic pathway with a very broad host spectrum to humans. Despite rising numbers of infections and potentially fatal outcomes, data on the molecular basis of pathogenicity are scarce. In this study, the interaction of 2 C. ulcerans isolates - one from an asymptomatic dog, one from a fatal case of human infection - with human macrophages was investigated. C. ulcerans strains were able to survive in macrophages for at least 20 hours. Uptake led to delay of phagolysosome maturation and detrimental effects on the macrophages as deduced from cytotoxicity measurements and FACS analyses. The data presented here indicate a high infectious potential of this emerging pathogen.

Recognition of Corynebacterium pseudodiphtheriticum by Toll-like receptors and up-regulation of antimicrobial peptides in human corneal epithelial cells.

Bacterial keratitis is a major cause of corneal ulcers in developing and industrialized nations. In this study, we examined the host innate immune responses to Corynebacterium pseudodiphtheriticum, often overlooked as commensal, in human corneal epithelial cells. The expressions of innate immune mediators were determined by quantitative PCR from corneal ulcers of patients and immortalized human corneal epithelial cells (HCEC). We have found an elevated expression of Toll like receptors (TLRs) along with IL-6 and IL-1ß from both ulcers and epithelial cells infected with C. pseudodiphtheriticum. Activation of NF-κB and MAPK signaling pathways were also observed in HCEC in response to C. pseudodiphtheriticum. In addition, we found a significant increase in the expression of antimicrobial peptides S100A8, S100A9 and human ß-defensin 1 from both corneal ulcers and HCEC.

Dysbiosis and Staphylococcus aureus Colonization Drives Inflammation in Atopic Dermatitis.

Staphylococcus aureus skin colonization is universal in atopic dermatitis and common in cancer patients treated with epidermal growth factor receptor inhibitors. However, the causal relationship of dysbiosis and eczema has yet to be clarified. Herein, we demonstrate that Adam17(fl/fl)Sox9-(Cre) mice, generated to model ADAM17-deficiency in human, developed eczematous dermatitis with naturally occurring dysbiosis, similar to that observed in atopic dermatitis. Corynebacterium mastitidis, S. aureus, and Corynebacterium bovis sequentially emerged during the onset of eczematous dermatitis, and antibiotics specific for these bacterial species almost completely reversed dysbiosis and eliminated skin inflammation. Whereas S. aureus prominently drove eczema formation, C. bovis induced robust T helper 2 cell responses. Langerhans cells were required for eliciting immune responses against S. aureus inoculation. These results characterize differential contributions of dysbiotic flora during eczema formation, and highlight the microbiota-host immunity axis as a possible target for future therapeutics in eczematous dermatitis.

Influence of Pluronic F127 on the distribution and functionality of inkjet-printed biomolecules in porous nitrocellulose substrates.

The distribution of inkjet-printed biomolecules in porous nitrocellulose substrates often results in a non-homogeneous spot morphology commonly referred to as 'doughnut-shaped' spots. We have studied the influence of Pluronic F127 (an amphiphilic surfactant) on the functionality of inkjet-printed primary antibody molecules and on the final assay result by performing a one-step antibody binding assay in the nitrocellulose substrate. The primary antibody was printed with and without Pluronic, followed by the addition of double-labelled amplicons as antigen molecules and a fluorophore-labelled streptavidin as detection conjugate. The distribution of the fluorescence intensity down into the nitrocellulose substrate was investigated by confocal laser scanning microscopy in 'Z' stacking mode. Each horizontal slice was further analysed by applying a concentric ring format and the fluorescence intensity in each slice was represented in a colour-coded way. The mean and total fluorescence intensity of the antibody binding assay (fluorescent streptavidin) showed a peak at 0.2% (w/v) Pluronic F127. In addition, an improved spot morphology was observed also peaking at the same Pluronic concentration. Subsequently, we investigated the direct influence of Pluronic F127 on the location of the primary antibody molecules by labelling these molecules with the fluorophore Alexa-488. Our results show that upon increasing the concentration of Pluronic F127 in the printing buffer, the spot diameter increased and the number of primary antibody molecules bound in the spot area gradually decreased. This was confirmed by analysing the distribution of fluorescently labelled primary antibody molecules down into the membrane layers. We conclude that a particular ratio between primary antibody and Pluronic F127 molecules in combination with available substrate binding capacity results in an optimal orientation, that is Fab-UP, of the primary antibody molecules. Consequently, an increased number of antigen molecules (in our case the labelled amplicons) and of the fluorescent detection conjugate (streptavidin) will give an optimal signal. Moreover, distribution of the primary antibody molecules was more homogeneous at the optimal Pluronic F127 concentration, contributing to the better spot morphology observed.

Skin microbiome imbalance in patients with STAT1/STAT3 defects impairs innate host defense responses.

BACKGROUND: Chronic mucocutaneous candidiasis (CMC) and hyper-IgE syndrome (HIES) are primary immunodeficiencies mainly caused by mutations in STAT1 and STAT3, respectively. CMC and HIES patients have an increased risk for skin and mucosal infections with fungal pathogens and Staphylococcus aureus. However, it is unknown whether the genetic defects in these patients also affect the skin and mucosal microbiome, which in turn may influence host defense mechanisms. METHODS: The skin and oral microbiome of CMC and HIES patients was compared to that of healthy controls at five body sites using 16S rRNA sequencing. The influence of skin colonizers on the immune response was investigated using in vitro experiments. RESULTS: The microbiome of CMC and HIES patients contained more Gram-negative bacteria, especially Acinetobacter spp., and less of the normal Corynebacterium spp. compared to healthy controls. Exposure of human primary leukocytes to Acinetobacter suppressed the cytokine response to Candida albicans and S. aureus, while the normal corynebacteria did not suppress cytokine responses. DISCUSSION: These results demonstrate that central mediators of immune responses like STAT1 and STAT3 not only directly influence immune responses, but also result in changes in the skin microbiome that in turn can amplify the defective immune response against fungal and microbial pathogens.

The altered landscape of the human skin microbiome in patients with primary immunodeficiencies.

While landmark studies have shown that microbiota activate and educate host immunity, how immune systems shape microbiomes and contribute to disease is incompletely characterized. Primary immunodeficiency (PID) patients suffer recurrent microbial infections, providing a unique opportunity to address this issue. To investigate the potential influence of host immunity on the skin microbiome, we examined skin microbiomes in patients with rare monogenic PIDs: hyper-IgE (STAT3-deficient), Wiskott-Aldrich, and dedicator of cytokinesis 8 syndromes. While specific immunologic defects differ, a shared hallmark is atopic dermatitis (AD)-like eczema. We compared bacterial and fungal skin microbiomes (41 PID, 13 AD, 49 healthy controls) at four clinically relevant sites representing the major skin microenvironments. PID skin displayed increased ecological permissiveness with altered population structures, decreased site specificity and temporal stability, and colonization with microbial species not observed in controls, including Clostridium species and Serratia marcescens. Elevated fungal diversity and increased representation of opportunistic fungi (Candida, Aspergillus) supported increased PID skin permissiveness, suggesting that skin may serve as a reservoir for the recurrent fungal infections observed in these patients. The overarching theme of increased ecological permissiveness in PID skin was counterbalanced by the maintenance of a phylum barrier in which colonization remained restricted to typical human-associated phyla. Clinical parameters, including markers of disease severity, were positively correlated with prevalence of Staphylococcus, Corynebacterium, and other less abundant taxa. This study examines differences in microbial colonization and community stability in PID skin and informs our understanding of host-microbiome interactions, suggesting a bidirectional dialogue between skin commensals and the host organism.

Function of milk polymorphonuclear neutrophil leukocytes in bovine mammary glands infected with Corynebacterium bovis.

Corynebacterium bovis is one of the most commonly isolated bacteria from aseptically collected bovine milk samples. The objective of the current study was to characterize the bovine innate immune response by evaluating milk polymorphonuclear neutrophilic leukocytes (PMNL) in mammary glands infected with C. bovis. Twenty quarters infected with C. bovis and 28 culture-negative quarters (with milk somatic cell count <1×10(5) cells/mL) were used. The percentages of milk PMNL and the PMNL expression of L-selectin (CD62L), ß2-integrin (CD11b), and one of the endothelial-selectin ligands (CD44), as well as the levels of intracellular reactive oxygen species (ROS) and the phagocytosis of Staphylococcus aureus, were evaluated by flow cytometry. The apoptosis and necrosis rates of the PMNL were quantified using dual-color flow cytometry with fluorescein-labeled annexin and propidium iodide. The present study revealed a higher percentage of PMNL in the milk from C. bovis-infected quarters, although no significant differences were found in levels of CD44, CD62L, or CD11b expression among the PMNL. A lower percentage of apoptotic PMNL was observed in C. bovis-infected quarters, as well as higher percentages of viable PMNL and of PMNL that produced intracellular ROS. However, no alterations were observed in phagocytosis of Staph. aureus by the PMNL or in intensity of intracellular ROS production by PMNL. Thus, results from this investigation of the PMNL function support, at least in part, the fact that intramammary infections by C. bovis may offer protection against intramammary infections by other bacteria.

Corynebacterium pyruviciproducens, as an immune modulator, can promote the activity of macrophages and up-regulate antibody response to particulate antigen.

Corynebacterium pyruviciproducens is a newly discovered Corynebacterium species with no known pathogenic components such as diphtheria toxin and tuberculostearic acid, and it has similar biological properties to Propionibacterium acnes, but its role of immunoregulation is drawing people's attention. In this work, based on the role of macrophages in removal of pathogenic bacteria as a primary scavenger and particulate antigen-presenting cell, the stimulation of macrophages by C. pyruviciproducens was analyzed through detecting the levels of cytokine secretion and expression of membrane molecules, and the effect of C. pyruviciproducens in promoting antibody response to sheep red blood cells (SRBC) in vivo was detected. In vitro, C. pyruviciproducens led to a sharp release of interleukin-6 and tumour necrosis factor-α and encouraged the activation of macrophages including enhanced expressions of MHC-II, CD40, CD80 and CD86. In vivo, it enhanced the humoral immune response against SRBC, a particulate antigen. These observations suggest that C. pyruviciproducens, as an immunoregulator, can promote the host humoral immune response to pathogenic microorganisms by regulating macrophage function.

[Production of cytokines by vaginal epitheliocytes in the process of interaction with dominant and associative microsymbionts].

AIM: Study the expression of cytokines by vaginal epitheliocytes in the process of interaction with dominant and associative microsymbionts. MATERIALS AND METHODS: IL-8, IL-6, IL-1beta and TNFalpha expression in response to interaction with heat inactivated Lactobacillus spp., Staphylococcus aureus, Escherichia coli, Corynebacterium spp. or their secretory products in comparison with basal expression of cytokines by vaginal epitheliocytes was studied. Results. Lactobacilli secretory products were shown not to influence the expression of IL-8 and IL-1beta and moderately stimulated IL-6 and TNFalpha expression. Contact of epitheliocytes with heat inactivated lactobacilli increased secretion of IL-8, IL-6 and IL-1beta and reduced TNFalpha production. Secretory products of S. aureus and E. coli caused stimulation of IL-6, IL-1beta production and practically did not change the expression of IL-8 and TNFalpha. Contact of epitheliocytes with heat inactivated S. aureus sup pressed TNFalpha production and had no influence on IL-8, IL-6 and IL-1beta expression, contact with E. colistimulated TNFalpha and IL-1beta expression and suppressed IL-6 expression. Changes in cytokine expression during interaction of epitheliocytes with corynebacteria were largely similar to the results of interaction with lactobacilli except IL-6 production that was markedly stimulated by corynebacteria secretory products. Conclusion. In epithelial-bacterial interactions dominant and associative microorganisms have a differential effect on functional status of mucosal epitheliocytes manifesting in production of cytokines that could be the basis of mucosal immunity regulation.

Targeting IL-23 by employing a p40 peptide-based vaccine ameliorates murine allergic skin and airway inflammation.

BACKGROUND: Studies have found that the IL-23/Th17 pathway plays an important role in the pathogenesis of atopic dermatitis (AD) and severe and steroid-resistant asthma. Targeting IL-23/Th17 pathway with monoclonal antibodies (mAb) has been successful in the reduction of skin and airway inflammation in animal models. However, the mAb has a short half-life, requiring repeated administrations. For the long-term suppression of IL-23/Th17 pathway, we have previously developed an IL-23p40 peptide-based virus-like particle vaccine, which induces long-lasting autoantibodies to IL-23. OBJECTIVE: We sought to evaluate the effects of this IL-23p40 peptide-based vaccine on the down-regulation of allergic skin and airway inflammation in mice. METHODS: Mice were subcutaneously injected three times with the IL-23p40 vaccine, or the vaccine carrier protein or saline as controls. Two weeks later, mice were epicutaneously sensitized with ovalbumin four times at a 2-week interval. One week after the final sensitization, mice were nasally administrated with ovalbumin daily for 3 days. One day later, bronchoalveolar lavage fluids (BALF), sera, lung and skin tissues were obtained and analysed. RESULTS: Mice immunized with the vaccine produced high levels of IgG antibodies to IL-23, p40 and IL-12 that in vitro inhibited IL-23-dependent IL-17 production. The numbers of total cells, neutrophils, and eosinophils in BALF were significantly reduced in the vaccine group, compared with controls. The levels of IL-13, IL-5, IL-23 and, IL-17 in BALF and levels of serum ovalbumin-specific IgE, IgG1, and total IgE were also significantly decreased. Histological analysis showed less inflammation of the lung and skin tissues in the vaccine group, compared with controls. CONCLUSION AND CLINICAL RELEVANCE: Administration of an IL-23p40 peptide-based vaccine down-regulates allergic skin and airway inflammation, suggesting that this strategy may be a potential therapeutic approach in the treatment of AD and asthma.