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A wide range of articles describe the role of different probiotics in the prevention or treatment of various diseases. However, currently, the focus is shifting from whole microorganisms to their easier-to-define components that can confer similar or stronger benefits on the host. Here, we aimed to describe polysaccharide B.PAT, which is a surface antigen isolated from Bifidobacterium animalis ssp. animalis CCDM 218 and to understand the relationship between its structure and function. For this reason, we determined its glycerol phosphate-substituted structure, which consists of glucose, galactose, and rhamnose residues creating the following repeating unit: To fully understand the role of glycerol phosphate substitution on the B.PAT function, we prepared the dephosphorylated counterpart (B.MAT) and tested their immunomodulatory properties. The results showed that the loss of glycerol phosphate increased the production of IL-6, IL-10, IL-12, and TNF-α in bone marrow dendritic cells alone and after treatment with Lacticaseibacillus rhamnosus GG. Further studies indicated that dephosphorylation can enhance B.PAT properties to suppress IL-1β-induced inflammatory response in Caco-2 and HT-29 cells. Thus, we suggest that further investigation of B.PAT and B.MAT may reveal distinct functionalities that can be exploited in the treatment of various diseases and may constitute an alternative to probiotics., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Nutraceuticals can reduce the risk of many diseases, such as cardiovascular disease, immune deficiencies, neurodegeneration, and others. Their delivery remains a challenge because it depends on many factors, most notably the stability of the bioactive compounds. Yolkin is a peptide complex isolated from hen egg yolk with immunomodulatory and neuroprotective potential. However, yolkin remains relatively poorly characterized. We aimed to determine the origin and glycosylation level of yolkin, its storage conditions, its thermal stability, and its aggregation ability and to assess its antioxidant, antihypertensive, and antidiabetic potential. The peptide composition of yolkin was shown to be homologous to that of vitellogenin II and vitellogenin I. These results indicate the stability of yolkin in a lyophilized form, preferably at 4 °C, with nonaggregation, antioxidant, and antidiabetic activities. As a result, yolkin can be considered to have significant therapeutic potential and represents a valuable tool for the development of novel nutraceuticals.

Escherichia coli A0 34/86 (EcO83) is a probiotic strain used in newborns to prevent nosocomial infections and diarrhoea. This bacterium stimulates both pro- and anti-inflammatory cytokine production and its intranasal administration reduces allergic airway inflammation in mice. Despite its benefits, there are concerns about the use of live probiotic bacteria due to potential systemic infections and gene transfer. Extracellular vesicles (EVs) derived from EcO83 (EcO83-EVs) might offer a safer alternative to live bacteria. This study characterizes EcO83-EVs and investigates their interaction with host cells, highlighting their potential as postbiotic therapeutics. EcO83-EVs were isolated, purified, and characterised following the Minimal Information of Studies of Extracellular Vesicles (MISEV) guidelines. Ex vivo studies conducted in human nasal epithelial cells showed that EcO83-EVs increased the expression of proteins linked to oxidative stress and inflammation, indicating an effective interaction between EVs and the host cells. Further in vivo studies in mice demonstrated that EcO83-EVs interact with nasal-associated lymphoid tissue, are internalised by airway macrophages, and stimulate neutrophil recruitment in the lung. Mechanistically, EcO83-EVs activate the NF-κΒ signalling pathway, resulting in the nitric oxide production. EcO83-EVs demonstrate significant potential as a postbiotic alternative to live bacteria, offering a safer option for therapeutic applications. Further research is required to explore their clinical use, particularly in mucosal vaccination and targeted immunotherapy strategies., (© 2024 The Author(s). Journal of Extracellular Vesicles published by Wiley Periodicals LLC on behalf of International Society for Extracellular Vesicles.)

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have already infected more than 0.7 billion people and caused over 7 million deaths worldwide. At the same time, our knowledge about this virus is still incipient. In some cases, there is a pre-pandemic immunity, however its source is unknown. The analysis of patients' humoral responses might shed a light on this puzzle. In this paper, we evaluated the antibody recognition of nucleocapsid protein, one of the structural proteins of SARS-CoV-2. For this purpose, we used pre-pandemic, acute COVID-19 and convalescent patients' sera to identify and map nucleocapsid protein epitopes. We identified a common epitope KKSAAEASKKPRQKRTATKA recognized by sera antibodies from all three groups. Some motifs of this sequence are widespread among various coronaviruses, plant or human proteins indicating that there might be more sources of nucleocapsid-reactive antibodies than previous infection with seasonal coronavirus. The two sequences MSDNGPQNQRNAPRITFGGP and KADETQALPQRQKKQQTVTL were detected as specific for sera from patients in acute phase of infection and convalescents making them suitable for future development of vaccine against SARS-CoV-2. Knowledge of the humoral response to SARS-CoV-2 infection is essential for the design of appropriate diagnostic tools and vaccine antigens., (© The Author(s) 2024. Published by Oxford University Press on behalf of FEMS.)

OBJECTIVE P. AERUGINOSA: (PA), the major pathogen of lung cystic fibrosis (CF), polarizes macrophages into hyperinflammatory tissue damaging phenotype. The main aim of this study was to verify whether training of macrophages with β-glucan might improve their response to P. aeruginosa infections., Methods: To perform this task C57BL/6 mice sensitive to infections with P. aeruginosa were used. Peritoneal macrophages were trained with Saccharomyces cerevisiae β-glucan and exposed to PA57, the strong biofilm-forming bacterial strain isolated from the patient with severe lung CF. The release of cytokines and the expression of macrophage phenotypic markers were measured. A quantitative proteomic approach was used for the characterization of proteome-wide changes in macrophages. The effect of in vivo β-glucan-trained macrophages in the air pouch model of PA57 infection was investigated. In all experiments the effect of trained and naïve macrophages was compared., Results: Trained macrophages acquired a specific phenotype with mixed pro-inflammatory and pro-resolution characteristics, however they retained anti-bacterial properties. Most importantly, transfer of trained macrophages into infected air pouches markedly ameliorated the course of infection. PA57 bacterial growth and formation of biofilm were significantly suppressed. The level of serum amyloid A (SAA), a systemic inflammation biomarker, was reduced., Conclusions: Training of murine macrophages with S. cerevisiae β-glucan improved macrophage defense properties along with inhibition of secretion of some detrimental inflammatory agents. We suggest that training of macrophages with such β-glucans might be a new therapeutic strategy in P. aeruginosa biofilm infections, including CF, to promote eradication of pathogens and resolution of inflammation., (© 2024. The Author(s).)

Highly stable, colloidal iron oxide nanoparticles with an oxyhydroxide-like surface were used as bacteria-capturing nano-baits. Peptidoglycan isolated from Listeria spp was used as bacteria polysaccharide model, and the nanoparticle binding was characterized showing a Langmuir isotherm constant, K L , equal to 50 ± 3 mL mg -1 . The chemical affinity was further supported by dynamic light scattering, transmission electron microscopy, and infrared and UV-Vis data, pointing at the occurrence of extended, coordinative multiple point bindings. The interaction with Gram (+) (Listeria spp) and Gram (-) (Aeromonas veronii) bacteria was shown to be effective and devoid of any toxic effect. Moreover, a real sample, containing a population of several oligotrophic bacteria strains, was incubated with 1 g L -1 of nanoparticle suspension, in the absence of agitation, showing a 100 % capture efficiency, according to plate count. A nanoparticle regeneration method was developed, despite the known irreversibility of such bacterial-nanosurface binding, restoring the bacteria capture capability. This nanomaterial represents a competitive option to eliminate microbiological contamination in water as an alternative strategy to antibiotics, aimed at reducing microbial resistance dissemination. Finally, beyond their excellent features in terms of colloidal stability, binding performances, and biocompatibility this nanoparticle synthesis is cost effective, scalable, and environmentally sustainable., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Bifidobacterium species are one of the most important probiotic microorganisms which are present in both, infants and adults. Nowadays, growing data describing their healthy properties arise, indicating they could act at the cellular and molecular level. However, still little is known about the specific mechanisms promoting their beneficial effects. Nitric oxide (NO), produced by inducible nitric oxide synthase (iNOS), is involved in the protective mechanisms in the gastrointestinal tract, where it can be provided by epithelial cells, macrophages, or bacteria. The present study explored whether induction of iNOS-dependent NO synthesis in macrophages stems from the cellular action of Bifidobacterium species. The ability of ten Bifidobacterium strains belonging to 3 different species (Bifidobacterium longum, Bifidobacterium adolescentis, and Bifidobacterium animalis) to activate MAP kinases, NF-κB factor, and iNOS expression in a murine bone-marrow-derived macrophages cell line was determined by Western blotting. Changes in NO production were determined by the Griess reaction. It was performed that the Bifidobacterium strains were able to induce NF-қB-dependent iNOS expression and NO production; however, the efficacy depends on the strain. The highest stimulatory activity was observed for Bifidobacterium animalis subsp. animals CCDM 366, whereas the lowest was noted for strains Bifidobacterium adolescentis CCDM 371 and Bifidobacterium longum subsp. longum CCDM 372. Both TLR2 and TLR4 receptors are involved in Bifidobacterium-induced macrophage activation and NO production. We showed that the impact of Bifidobacterium on the regulation of iNOS expression is determined by MAPK kinase activity. Using pharmaceutical inhibitors of ERK 1/2 and JNK, we confirmed that Bifidobacterium strains can activate these kinases to control iNOS mRNA expression. Concluding, the induction of iNOS and NO production may be involved in the protective mechanism of action observed for Bifidobacterium in the intestine, and the efficacy is strain-dependent., (© 2023. The Author(s).)

Background: The impact of probiotic strains on host health is widely known. The available studies on the interaction between bacteria and the host are focused on the changes induced by bacteria in the host mainly. The studies determining the changes that occurred in the bacteria cells are in the minority. Within this paper, we determined what happens to the selected Bifidobacterium adolescentis and Bifidobacterium longum ssp. longum in an experimental environment with the intestinal epithelial layer. For this purpose, we tested the bacteria cells' viability, redox activity, membrane potential and enzymatic activity in different environments, including CaCo-2/HT-29 co-culture, cell culture medium, presence of inflammatory inductor (TNF-α) and oxygen., Results: We indicated that the external milieu impacts the viability and vitality of bacteria. Bifidobacterium adolescentis decrease the size of the live population in the cell culture medium with and without TNF-α (p < 0.001 and p < 0.01 respectively). In contrast, Bifidobacterium longum ssp. longum significantly increased survivability in contact with the eukaryotic cells and cell culture medium (p < 0.001). Bifidobacterium adolescentis showed significant changes in membrane potential, which was decreased in the presence of eukaryotic cells (p < 0.01), eukaryotic cells in an inflammatory state (p < 0.01), cell culture medium (p < 0.01) and cell culture medium with TNF-α (p < 0.05). In contrast, Bifidobacterium longum ssp. longum did not modulate membrane potential. Instead, bacteria significantly decreased the redox activity in response to milieus such as eukaryotic cells presence, inflamed eukaryotic cells as well as the culture medium (p < 0.001). The redox activity was significantly different in the cells culture medium vs the presence of eukaryotic cells (p < 0.001). The ability to β-galactosidase production was different for selected strains: Bifidobacterium longum ssp. longum indicated 91.5% of positive cells, whereas Bifidobacterium adolescentis 4.34% only. Both strains significantly reduced the enzyme production in contact with the eukaryotic milieu but not in the cell culture media., Conclusion: The environmental-induced changes may shape the probiotic properties of bacterial strains. It seems that the knowledge of the sensitivity of bacteria to the external environment may help to select the most promising probiotic strains, reduce research costs, and contribute to greater reproducibility of the obtained probiotic effects., (© 2024. The Author(s).)

Background: Microbiome dysbiosis plays a role in the pathogenesis of many urological diseases, including bladder cancer (BC). The aim of the study was to compare the urinary and gut microbiota of patients with BC with a healthy control (HC) group., Methods: The study group included patients hospitalized in 2020 to 2021 with diagnosed BC and HC. Prior to the transurethral resection of bladder tumor, patients collected their urine and stool which was then subjected to 16S rRNA gene sequencing., Results: Overall, 25 patients were enrolled in the study: 18 in the BC group and 7 in the HC group. Analysis of the urine and stool microbiome showed no statistically significant differences between patients with BC and HC in alpha diversity, beta diversity, and difference in taxa relative abundance. Detailed analysis of urine and stool microbiome depending on patient- and tumor-related characteristics also showed no statistically significant differences in alpha diversity and beta diversity. Differences in abundance (ANCOM) were noted in both types of samples in patients with BC. In the urine test, genus Lactobacillus was more common in patients with a positive history of Bacillus Calmette-Guérin (BCG) therapy, while genus Howardella and the strain Streptococcus anginosus were more common in women. In stool samples, abundance of phylum Desulfobacterota was most abundant in Grade G1 and least in G2. Class Alphaproteobacteria , order Rhodospirillales , order Flavobacteriales , and family Flavobacteriaceae were more common in women., Conclusions: The microbiome of urine and stool of patients with BC does not differ significantly from that of HC; however, its composition in patients with BC varies according to the patient's sex., Competing Interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2023.)

Bifidobacteria are among the most common bacteria used for their probiotic properties and their impact on the maturation and function of the immune system has been well-described. Recently, scientific interest is shifting from live bacteria to defined bacteria-derived biologically active molecules. Their greatest advantage over probiotics is the defined structure and the effect independent of the viability status of the bacteria. Here, we aim to characterize Bifidobacterium adolescentis CCDM 368 surface antigens that include polysaccharides (PSs), lipoteichoic acids (LTAs), and peptidoglycan (PG). Among them, Bad368.1 PS was observed to modulate OVA-induced cytokine production in cells isolated from OVA-sensitized mice by increasing the production of Th1-related IFN-γ and inhibition of Th2-related IL-5 and IL-13 cytokines (in vitro). Moreover, Bad368.1 PS (BAP1) is efficiently engulfed and transferred between epithelial and dendritic cells. Therefore, we propose that the Bad368.1 PS (BAP1) can be used for the modulation of allergic diseases in humans. Structural studies revealed that Bad368.1 PS has an average molecular mass of approximately 9,99 × 10 6  Da and it consists of glucose, galactose, and rhamnose residues that are creating the following repeating unit: →2)-β-D-Glcp-1→3-β-L-Rhap-1→4-β-D-Glcp-1→3-α-L-Rhap-1→4-β-D-Glcp-1→3-α-D-Galp-(1→ n ., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Objective: Lung cystic fibrosis (CF) is characterized by chronic infections and hyperinflammatory response of neutrophils and macrophages. P. aeruginosa (PA) and S. aureus (MSSA, MRSA) are major pathogens of advanced CF. The main goal of this study was to compare the inflammatory phenotype of murine C57BL/6 macrophages exposed to PA57 with that exposed to MSSA60, both strains isolated from the same patient with severe CF. In the present study, we used C57BL/6 mice sensitive to lung infection with P. aeruginosa., Methods: We measured the release of cytokines and the expression of phenotypic markers of murine neutrophils and macrophages exposed to bacterial cells and biofilm components (i.e., EPS) of the selected bacteria. In addition, a quantitative proteomic approach was used for the characterization of proteome-wide changes in macrophages., Results: Neutrophils stimulated with PA57 and MSSA60 strains produced hyperinflammatory pattern of cytokines. The pro-inflammatory impact of PA57 was significantly higher than that of MSSA60 (IL-6/IL-10 ratio: PA57 = 9.3 vs. MSSA60 = 1.7). Macrophages produced significantly lower amount of cytokines, but showed classical pattern of M1 markers (iNOS-High; arginase-1 and mannose receptor MRC1-Low). Importantly, as evidenced by proteomic analysis, PA57 and PA57-EPS were stronger inducers of M1 macrophage polarization than the MSSA60 counterparts., Conclusions: Our study demonstrated that strong biofilm P. aeruginosa strains, CF isolates, are dominant inducers of M1 macrophages, termed biofilm-associated macrophages (BAMs). We suggest that repolarization of detrimental BAMs might be a new therapeutic strategy to ameliorate the airway damage in CF., (© 2023. The Author(s).)

Clostridioides difficile (CD) is a Gram-positive, anaerobic bacterium that infects mainly hospitalized and elderly people who have been treated with long-term antibiotic therapy leading to dysbiosis. The deteriorating demographic structure and the increase in the number of antibiotics used indicate that the problem of CD infections (CDI) will continue to increase. Thus far, there is no vaccine against CD on the market. Unfortunately, clinical trials conducted using the CD toxin-based antigens did not show sufficiently high efficacy, because they did not prevent colonization and transmission between patients. It seems that the vaccine should also include antigens found in the bacterium itself or its spores in order not only to fight the effects of toxins but also to prevent the colonization of the patient. This literature review summarizes the latest advances in research into vaccine antigens that do not contain CD toxins.

Background and Objectives: Global policy emphasizes the need to promote healthy aging through supporting inclusivity, safety, and functional independence. Research indicates that efforts to enhance resilience can contribute to meeting these objectives. We employed a meta-analytical approach to examine evidence on resilience in community-living older adults., Research Design and Methods: We searched electronic databases until January 13, 2020 for observational studies investigating factors associated with resilience in this population. Articles had to provide quantitative data based on standardized assessment and include samples where mean participants' age and lower 95% confidence interval were more than 55 years. We included 49 studies reported in 43 articles and completed 38 independent meta-analyses, 27 for personal and 11 for contextual factors associated with resilience., Results: A range of personal and contextual factors were significantly associated with resilience, with effects sizes predominantly small to moderate (0.1 < r < 0.49). Factors reflecting psychological and physical well-being and access to/quality of social support were associated with higher resilience. Factors indicative of poorer psychological well-being and social challenges were associated with lower resilience. Longitudinal evidence was limited. The level of between-study heterogeneity was substantial to considerable. Where relevant analysis was possible, the identified publication bias was also considerable., Discussion and Implications: The quality of the available evidence, as well as issues related to measurement of resilience, indicates the need for further work relative to its conceptualization and assessment. The presented findings have important clinical implications, particularly within the context of the coronavirus disease 2019 impact on resilience in older adults., (© The Author(s) 2021. Published by Oxford University Press on behalf of The Gerontological Society of America.)

In recent years a continuous increase in new cases of respiratory disorders, such as rhinitis, asthma, and chronic obstructive pulmonary disease (COPD), has been observed. The exact pathomechanism of these diseases is still blurry, resulting in the lack of targeted and effective therapy. The conventional use of treatment strategies, such as antihistamine drugs and/or glucocorticosteroids act mainly symptomatically and have significant side effects. Specific allergen immunotherapy is only useful in the management of specific allergies and selected patients. Therefore, new therapeutic solutions are constantly being sought. The novelty of recent years has been the association between NLRP3 inflammasome activation and the development of airway inflammatory diseases. This seems to be an interesting therapeutic target that may support or even replace traditional therapies in the future. The review presented, discusses the contribution of NLRP3 inflammasome to the development of allergic rhinitis, allergic asthma, and COPD. Moreover, the modulatory properties of probiotics as potential inhibitors of NLRP3 inflammasome are emphasised., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Leszczyńska, Jakubczyk and Górska.)

Most pathogens enter the body through the surfaces of the mucous membranes, e.g. the nose or the intestines. The mucosal immune response is essential for the effective elimination of invading pathogens. Unfortunately, most vaccines which are administered intramuscularly by injection do not induce an adequate protective immune response on mucous membranes. For example, after intramuscular injection, the level of secretory IgA antibodies is low and often insufficient to successfully combat the pathogen. On the other hand, mucosal-induced immunity produces a long-lasting effect in the form of a local and systemic response to the pathogen. Moreover, the administration of such vaccines does not generate hazardous medical waste and their application does not require the presence of qualified medical personnel. Therefore, intensive research into vaccines administered via the mucosal route is ongoing. An obstacle in the development of mucosal vaccines is the natural defense mechanisms of the mucosa, the overcoming of which requires the use of specialized adjuvants. Currently, there are no such formulations on the market.

Group B streptococcus (GBS) is one of the uropathogens that causes urinary tract infections (UTIs). The aims of this article were molecular characterization, an analysis of antimicrobial susceptibility profiles, adherence to bladder endothelial cells, and the detection of immunoreactive proteins of 94 clinical strains of GBS isolated from adult Polish patients with UTI. Antibiotic susceptibilities were determined by disk diffusion. Serotyping and Alp family genes detection were studied using multiplex PCR. Genetic profiles were determined by pulsed-field gel electrophoresis. The adherence ability of the studied strains was estimated by incubation on human bladder microvascular endothelial cell line. Immunoreactive proteins were studied by immunoblotting. Antibiotic susceptibility investigation revealed that 22% of GBS strains were resistant to erythromycin, whereas 18% demonstrated resistance to clindamycin. cMLS B was present in 76% of the resistant strains, M phenotype was detected in 14%, whereas iMLS B was present for 10%. The most common serotype was serotype III (31%), followed by serotype V (27%), and serotype Ia (17%). The genes that dominated among other Alp genes were: epsilon (29%), alp 2 (27%), and rib (23%). The most common co-occurring serotypes and Alp genes were: Ia and epsilon , III and rib , III and alp 2, V and alp 2, and V and alp 3 ( p < 0.001). The PFGE method showed high clonality for serotype V and cMLS B ( p < 001). The PFGE method showed high clonality for serotype V. Furthermore, this serotype was significantly associated with the cMLS B phenotype ( p < 0.001). The most common immunoreactive proteins demonstrated masses of 50 kDa and 45-47 kDa. Although examined GBS isolates showed high genetic diversity, immunoreactive proteins were common for most of the studied GBS isolates, which may indicate their conservation, and allows to consider them as potential immunodiagnostic markers. Although the examined GBS isolates showed high genetic diversity, immunoreactive proteins were shared by most of the studied GBS isolates. It may indicate their conservation, thus allowing to consider them as potential immunodiagnostic markers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Dobrut, Ochońska, Brzozowska, Górska, Kaszuba-Zwoinska, Gołda-Cępa, Gamian and Brzychczy-Wloch.)

Ageing is accompanied by the inevitable changes in the function of the immune system. It provides increased susceptibility to chronic infections that have a negative impact on the quality of life of older people. Therefore, rejuvenating the aged immunity has become an important research and therapeutic goal. Yolkin, a polypeptide complex isolated from hen egg yolks, possesses immunoregulatory and neuroprotective activity. Considering that macrophages play a key role in pathogen recognition and antigen presentation, we evaluated the impact of yolkin on the phenotype and function of mouse bone marrow-derived macrophages of the BMDM cell line. We determined yolkin bioavailability and the surface co-expression of CD80/CD86 using flow cytometry and IL-6, IL-10, TGF-β and iNOS mRNA expression via real-time PCR. Additionally, the impact of yolkin on the regulation of cytokine expression by MAPK and PI3K/Akt kinases was determined. The stimulation of cells with yolkin induced significant changes in cell morphology and an increase in CD80/CD86 expression. Using pharmaceutical inhibitors of ERK, JNK and PI3K/Akt, we have shown that yolkin is able to activate these kinases to control cytokine mRNA expression. Our results suggest that yolkin is a good regulator of macrophage activity, priming mainly the M1 phenotype. Therefore, it is believed that yolkin possesses significant therapeutic potential and represents a promising possibility for the development of novel immunomodulatory medicine.

In continuation of our research on the influence of selenium incorporation on the biosynthesis, structure, and immunomodulatory and antioxidant activities of polysaccharides of fungal origin, we have isolated from a post-culture medium of Lentinula edodes a selenium (Se)-containing exopolysaccharide fraction composed mainly of a highly branched 1-6-α-mannoprotein of molecular weight 4.5 × 10 6 Da, with 15% protein component. The structure of this fraction resembled mannoproteins isolated from yeast and other mushroom cultures, but it was characterized by a significantly higher molecular weight. X-ray absorption fine structure spectral analysis in the near edge region (XANES) suggested that selenium in the Se-exopolysaccharide structure was present mainly at the IV oxidation state. The simulation analysis in the EXAFS region suggested the presence of two oxygen atoms in the region surrounding the selenium. On the grounds of our previous studies, we hypothesized that selenium-enriched exopolysaccharides would possess higher biological activity than the non-Se-enriched reference fraction. To perform structure-activity studies, we conducted the same tests of biological activity as for previously obtained mycelial Se-polyglucans. The Se-enriched exopolysaccharide fraction significantly enhanced cell viability when incubated with normal (human umbilical vein endothelial cells (HUVEC)) cells (but this effect was absent for malignant human cervical HeLa cells) and this fraction also protected the cells from oxidative stress conditions. The results of tests on the proliferation of human peripheral blood mononuclear cells suggested a selective immunosuppressive activity, like previously tested Se-polyglucans isolated from L. edodes mycelium. The Se-exopolysaccharide fraction, in concentrations of 10-100 µg/mL, inhibited human T lymphocyte proliferation induced by mitogens, without significant effects on B lymphocytes. As with previously obtained Se-polyglucans, in the currently tested Se-polymannans, the selenium content increased the biological activity. However, the activity of selenium exopolysaccharides in all tests was significantly lower than that of previously tested mycelial isolates, most likely due to a different mode of selenium binding and its higher degree of oxidation.

The chemical structure of the lipopolysaccharide O-polysaccharide repeating unit of Edwardsiella tarda strain PCM 1155 was studied for the first time. The complete structure of repeating unit was investigated by chemical methods, 1 H and 13 C nuclear magnetic resonance (NMR) spectroscopy, and matrix-assisted laser-desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS). The rarely occurring monosaccharide, 2,3-diacetamido-2,3,6-trideoxy-l-mannose (L-RhapNAc3NAc) was identified. The following structure was established., (Copyright © 2021 The Author(s). Published by Elsevier Ltd.. All rights reserved.)

We previously described the biosynthesis, isolation, and immunosuppressive activity of the selenium-containing polysaccharide fraction isolated from the mycelial culture of Lentinula edodes . Structural studies have shown that the fraction was a protein-containing mixture of high molar mass polysaccharides α- and β-glucans. However, which of the components of the complex fraction is responsible for the immunosuppressive activity non-typical for polysaccharides of fungal origin has not been explained. In the current study, we defined four-polysaccharide components of the Se-containing polysaccharide fraction determined their primary structure and examined the effect on T- and B-cell proliferation. The isolated Se-polysaccharides, α-1,4-glucan (M w 2.25 × 10 6 g/mol), unbranched β-1,6-d-glucan, unbranched β-1,3-d-glucan and β-1,3-branched β-1,6-d-glucan (M w 1.10 × 10 5 g/mol), are not typical as components of the cell wall of L. edodes . All are biologically active, but the inhibitory effect of the isolated polysaccharides on lymphocyte proliferation was weaker, though more selective than that of the crude fraction.

Background and Objectives: Previous efforts to develop a resilience measure for older adults have largely failed to consider the environmental influences on their resilience, and have primarily concentrated on the resilience of community-dwelling older adults. Our objective was to validate a new multidimensional measure of resilience, the Making it CLEAR (MiC) questionnaire, for use with older adults at the point of discharge from hospital., Research Design and Methods: This study tested the structure, validity, and reliability of the MiC questionnaire. The questionnaire consists of 34 items, which assess the "individual determinants of resilience" (IDoR) and the "environmental determinants of resilience" (EDoR) across 2 subscales. 416 adults aged 66-102 years participated. Exploratory factor analysis, item analysis, and linear regression were undertaken., Results: The IDoR subscale contained six factors which were labeled "Self-efficacy," "Values," "Interpersonal skills," "Life orientation," "Self-care ability," and "Process skills." The EDoR subscale contained five factors related to "Person-environment fit," "Friends," "Material assets," "Habits," and "Family." Both subscales demonstrated acceptable convergent validity and internal consistency, while individual items showed acceptable levels of discrimination and difficulty., Discussion and Implications: The study provides evidence supporting the validity and quality of the MiC questionnaire. The results suggest that the MiC questionnaire could be used to identify the resilience needs of older adults at the point of hospital discharge. However, future research should identify which items of the MiC questionnaire are associated with hospital readmission, in order to develop an easily applicable screening tool for clinical practice., (© The Author(s) 2021. Published by Oxford University Press on behalf of The Gerontological Society of America.)

Background and Objectives: General self-efficacy (GSE) encourages health-promoting behaviors in older adults. It is unsurprising then that older adults receiving health care services are reported to have a greater risk of low GSE than older adults who are not. Despite this, there is currently limited evidence investigating whether the effect differs based on the environment in which care is received. This review aims to determine whether the GSE of older adults is affected by the receipt of health care services and whether GSE varies based on the setting in which care is received., Research Design and Methods: In accordance with PRISMA guidelines (PROSPERO registration number CRD42018092191), a systematic search was undertaken across 7 databases. Standardized mean differences (SMD) and mean General Self-Efficacy Scale scores, with 95% confidence intervals (CI), were pooled for meta-analysis., Results: A total of 40 studies were identified, they consisted of 33 population cohorts that were included in the meta-analysis. Older adults receiving health care services were found to be at greater risk of having lower GSE than those who do not (SMD = -0.62; 95% CI: -0.96 to -0.27, p < .0001). Following identification of sources of heterogeneity, older adults receiving acute inpatient care were more likely to have lower GSE than those receiving care in other health care settings., Discussion and Implications: Older adults receiving inpatient care have a greater risk of lower GSE, and consequently, poorer health-promoting behaviors. Further research is recommended that focuses on the GSE of older adults and health outcomes following discharge from inpatient care., (© The Author(s) 2020. Published by Oxford University Press on behalf of The Gerontological Society of America.)

The classical definition of probiotics states that bacteria must be alive to be beneficial for human organism. However, recent reports show that inactivated bacteria or their effector molecules can also possess such properties. In this study, we investigated the physical and immunomodulatory properties of four Bifidobacterium strains in the heat-treated (HT) and untreated (UN) forms. We showed that temperature treatment of bacteria changes their size and charge, which affects their interaction with epithelial and immune cells. Based on the in vitro assays, we observed that all tested strains reduced the level of OVA-induced IL-4, IL-5, and IL-13 in the spleen culture of OVA-sensitized mice. We selected Bifidobacterium longum ssp. longum CCM 7952 (Bl 7952) for further analysis. In vivo experiments confirmed that untreated Bl 7952 exhibited allergy-reducing properties when administered intranasally to OVA-sensitized mice, which manifested in significant suppression of airway inflammation. Untreated Bl 7952 decreased local and systemic levels of Th2 related cytokines, OVA-specific IgE antibodies and simultaneously inhibited airway eosinophilia. In contrast, heat-treated Bl 7952 was only able to reduce IL-4 levels in the lungs and eosinophils in bronchoalveolar lavage, but increased neutrophil and macrophage numbers. We demonstrated that the viability status of Bl 7952 is a prerequisite for the beneficial effects of bacteria, and that heat treatment reduces but does not completely abolish these properties. Further research on bacterial effector molecules to elucidate the beneficial effects of probiotics in the prevention of allergic diseases is warranted., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Pyclik, Srutkova, Razim, Hermanova, Svabova, Pacyga, Schwarzer and Górska.)

Respiratory allergy is a common disease with an increased prevalence worldwide. The effective remedy is still unknown, and a new therapeutic approach is highly desirable. The review elaborates the influence of probiotic bacteria on respiratory allergy prevention and treatment with particular emphasis on the impact of the current methods of their administration - oral and intranasal. The background of the respiratory allergy is complex thus, we focused on the usefulness of probiotics in the alleviation of different allergy factors, in particular involved in pathomechanism, local hypersensitive evidence and the importance of epithelial barrier. In this review, we have shown that (1) probiotic strains may vary in modulatory potential in respiratory allergy, (2) probiotic bacteria are beneficial in oral and intranasal administration, (3) recombinant probiotic bacteria can modulate the course of respiratory allergy., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Jakubczyk and Górska.)

Many conventional vaccines are administered via a needle injection, while most pathogens primarily invade the host via mucosal surfaces. Moreover, protective IgA antibodies are insufficiently induced by parenteral vaccines. Mucosal immunity induces both local and systemic response to pathogens and typically lasts for long periods of time. Therefore, vaccination via mucosal routes has been increasingly explored. However, mucosal vaccines require potent adjuvants to become efficacious. Despite many efforts to develop safe and robust adjuvants for mucosal vaccines, only a few have been approved for use in human formulations. The aim of our study was to design, develop and characterize new silicone oil-based nanoadjuvant candidates for intranasal vaccines with potential to become mucosal adjuvants. We have developed an array of nanoadjuvant candidates (NACs), based on well-defined ingredients. NAC1, 2 and 3 are based on silicone oil, but differ in the used detergents and organic solvents, which results in variations in their droplet size and zeta potential. NACs' cytotoxicity, Tumor Necrosis Factor α (TNF-α) induction and their effect on antigen engulfment by immune cells were tested in vitro. Adjuvant properties of NACs were verified by intranasal vaccination of mice together with ovalbumin (OVA). NACs show remarkable stability and do not require any special storage conditions. They exhibit bio-adhesiveness and influence the degree of model protein engulfment by epithelial cells. Moreover, they induce high specific anti-OVA IgG antibody titers after two intranasal administrations. Nanoadjuvant candidates composed of silicone oil and cationic detergents are stable, exhibit remarkable adjuvant properties and can be used as adjuvants for intranasal immunization.

Objectives: To provide prevalence estimates of needs of people with dementia living at home, and to determine sources of variation associated with needs for this population., Method: A systematic review and meta-analysis was performed searching CINAHL, MEDLINE, PsycINFO and ASSIA databases. Following quality checks, random effects meta-analysis produced prevalence estimates for needs reported by people with dementia and by their informal caregivers. Fixed effects models were undertaken to compare caregiver and person with dementia reported needs. Heterogeneity was explored through sensitivity analysis. The study protocol was registered with Prospero #CRD42017074119., Results: Six retrieved studies published between 2005 and 2017 including 1011 people with dementia and 1188 caregivers were included in the analysis. All data were collected using Camberwell Assessment of Need for the Elderly. Prevalence estimates are provided for 24 needs reported by participants in The Netherlands, United Kingdom, Poland, Ireland, Germany, Norway, Portugal, Italy and Sweden. Most prevalent needs reported by people with dementia were Memory 0.713 [95% CI 0.627, 0.791]; Food 0.706 [95% CI 0.547, 0.842]; Household activities 0.677 [95% CI 0.613, 0.738]; and Money 0.566 [95% CI 0.416, 0.711]. Caregivers reported greater prevalence than people with dementia did for 22 of 24 needs, although the priority ranking of needs was similar. Exploration of heterogeneity revealed that people with young onset dementia were the major source of variation for 24 out of 48 analyses., Conclusion: Increased understanding of prevalence of needs of people with dementia and associated heterogeneity can assist in planning services to meet those needs.

Activation of TLR7 by small imidazoquinoline molecules such as R848 or R837 initiates signaling cascades leading to the activation of transcription factors, such as AP-1, NF-κB, and interferon regulatory factors (IRFs) and afterward to the induction of cytokines and anti-viral Type I IFNs. In general, TLRs mediate these effects by utilizing different intracellular signaling molecules, one of them is Mal. Mal is a protein closely related to the antibacterial response, and its role in the TLR7 pathways remains poorly understood. In this study, we show that Mal determines the expression and secretion of IFNβ following activation of TLR7, a receptor that recognizes ssRNA and imidazoquinolines. Moreover, we observed that R848 induces Mal-dependent IFNβ production via ERK1/2 activation as well as the transcription factor IRF7 activation. Although activation of TLR7 leads to NF-κB-dependent expression of IRF7, this process is independent of Mal. We also demonstrate that secretion of IFNβ regulated by TLR7 and Mal in macrophages and dendritic cells leads to the IP-10 chemokine expression. In conclusion, our data demonstrate that Mal is a critical regulator of the imidazoquinolinones-dependent IFNβ production via ERK1/2/IRF7 signaling cascade which brings us closer to understanding the molecular mechanism's regulation of innate immune response.

Inflammatory bowel disease (IBD), which affects millions of people worldwide, includes two separate diseases: Crohn's disease (CD) and ulcerative colitis (UC). Although the background (chronic inflammatory state) and some of the symptoms of CD and UC are similar, both diseases differ from each other. It is becoming clear that a combination of many factors, in particular genetic background, host immune response and microbial reduced diversity status are associated with IBD. One potential strategy to prevent/treat IBD is gut modulation by probiotics. Over the last twenty years, many publications have focused on the role of probiotics in the course of IBD. The review discusses the utility of different strains of probiotics, especially Bifidobacterium spp., in all factors potentially involved in the etiology of IBD. The probiotic modulatory properties among different study models (cell lines, animal models of colitis, clinical study) are discussed and probiotic usefulness is assessed in relation to the treatment, prevention, and remission of diseases.

Vaccination has been well recognised as a critically important tool in preventing infectious disease, yet incomplete immunisation coverage remains a major obstacle to achieving disease control and eradication. As medical products for global access, vaccines need to be safe, effective and inexpensive. In line with these goals, continuous improvements of vaccine delivery strategies are necessary to achieve the full potential of immunisation. Novel technologies related to vaccine delivery and route of administration, use of advanced adjuvants and controlled antigen release (single-dose immunisation) approaches are expected to contribute to improved coverage and patient compliance. This review discusses the application of micro- and nano-technologies in the alternative routes of vaccine administration (mucosal and cutaneous vaccination), oral vaccine delivery as well as vaccine encapsulation with the aim of controlled antigen release for single-dose vaccination.

Exopolysaccharides (EPSs), major components of the bacterial biofilm, display strong strain-specific immunomodulatory properties. Previously, we have shown that crude EPS derived from Lactobacillus rhamnosus KL37 depresses the production of arthritogenic anti-collagen IgG and ameliorates collagen-induced arthritis (CIA) in DBA/1 mice, when lipopolysaccharide (LPS) was used as adjuvant. In this study, we used highly purified EPS from L. rhamnosus KL37 (EPS-37) to verify its anti-inflammatory properties and the ability to suppress T cell-dependent humoral response. We have employed the model of active CIA, in which mice immunized with type II collagen (CII) along with LPS were treated with pure EPS-37. Intravenous administration of purified EPS-37 markedly ameliorated arthritis and reduced CII-specific antibody production. EPS-37 injected subcutaneously reduced the clinical symptoms of CIA but without the reduction of arthritogenic antibodies. In addition, the effect of EPS-37 on T-cell functions was tested ex vivo and in vitro. EPS-37 inhibited the in vitro proliferation of T cells activated both in vivo (CII immunization) and in vitro (antigen/mitogen), and markedly reduced the production of interferon (IFN)-γ. These results together with other reports suggest that anti-inflammatory potential of EPS-37 depends on its ability to inhibit either one or the other or both possible inflammatory signaling pathways. Namely, Th1 → IFN-γ → M1 inflammatory macrophages → arthritis and/or Th1 → IFN-γ → B cells → arthritogenic antibodies → arthritis. We suggest that L. rhamnosus KL37 EPS might be utilized to control T cell-dependent immune responses in various inflammatory diseases. However, the most effective route of EPS-37 administration needs to be tailored for a given disorder.

Clostridioides difficile (CD) is a Gram-positive pathogen responsible for CD-associated disease (CDAD), which is characterized by symptoms ranging from mild diarrhea to pseudomembranous colitis. This work is an attempt to respond to the need of novel methods for CD infection (CDI) prevention, since the number of CDI cases is still rising. A bioinformatics approach was applied to design twenty-one peptides consisting of in silico predicted linear B-cell and T-cell epitopes of aminopeptidase M24 from CD. These peptides were mapped for epitopes exploiting PEPSCAN procedure and using sera obtained from CD infected patients, umbilical cord blood, and healthy volunteers. Two new CD epitopes, 131 KKGIK 135 and 184 KGTSTHVIT 192 , were identified and characterized. Immunoreactivity of the synthetic biotinylated 131 KKGIK 135 epitope was significantly higher compared to 184 KGTSTHVIT 192 epitope in Enzyme-Linked Immunosorbent Assay (ELISA) with umbilical cord blood and CDI patients' sera. Hereafter, the conjugate of bovine serum albumin and epitope 131 KKGIK 135 was evaluated in vitro on lung epithelial cell line. In vitro, a significant induction of IL-6 by conjugate was observed, thereby we postulate that this new 131 KKGIK 135 epitope possesses immunostimulating properties suggesting possibility of its use in a vaccine against Clostridioides difficile .

A variety of health benefits has been documented to be associated with the consumption of probiotic bacteria, namely bifidobacteria and lactobacilli. Thanks to the scientific advances in recent years we are beginning to understand the molecular mechanisms by which bacteria in general and probiotic bacteria in particular act as host physiology and immune system modulators. More recently, the focus has shifted from live bacteria towards bacteria-derived defined molecules, so called postbiotics. These molecules may represent safer alternative compared to the live bacteria while retaining the desired effects on the host. The excellent source of effector macromolecules is the bacterial envelope. It contains compounds that are pivotal in the adhesion phenomenon, provide direct bacteria-to-host signaling capacity and the associated physiological impact and immunomodulatory properties of bacteria. Here we comprehensively review the structure and biological role of Bifidobacterium surface and cell wall molecules: exopolysaccharides, cell wall polysaccharides, lipoteichoic acids, polar lipids, peptidoglycans and proteins. We discuss their involvement in direct signaling to the host cells and their described immunomodulatory effects., (Copyright © 2020 Elsevier B.V. All rights reserved.)

This paper presents a microwave sensor designed as a capacitive matrix for label-free Escherichia coli detection. The mean value of capacitances' change in the capacitive matrix sensor is an indicator of the bacteria detection. The theoretical analysis was confirmed by the realization of an exemplary sensor chip manufactured using the United Monolithic Semiconductor (UMS) PH25 process on a 100 μm thick GaAs substrate and measurements of various concentrations of Escherichia coli in the frequency range 1-3 GHz. The matrix topology of the sensor together with biofunctionalization of the sensor surface with polyclonal anti-Escherichia coli antibody allow to obtain high detection sensitivity on various concentrations of Escherichia coli reaching 10 3  CFU/ml. The obtained results are promising for future biomedical applications, in terms of specific bacteria presence detection., (Copyright © 2019 Elsevier B.V. All rights reserved.)

Clostridioides difficile (CD) cause a severe diarrhea which can lead to pseudomembranous colitis and even patient death. CD infection (CDI) is connected mainly with changes in intestinal microbiota as a consequence of antibiotic treatment. The growing resistance to antibiotics, justifies the search for new methods of combating CD. Despite of ongoing research on the immunity against the pathogen, there is still lack of any reliable vaccine. Most recently, Cwp22, that is a cross-linking enzyme involved in the production of CD peptidoglycan, seems to be a promising target to prevent CDI in high-risk patients. In this paper, the Cwp22 protein polypeptide-specific epitopes were mapped in silico and using PEPSCAN procedure. They were recognized not only by antibodies from CDI patients' but also by umbilical cord blood sera. We identified three epitopes 54 EFRVAT 59 , 201 KVNGKM 20 6 and 268 WQEKNGKKYY 277 of Cwp22 protein. Since Cwp22 protein has key functionality and the described above epitopes are also recognized by umbilical cord blood serum, we postulate that they could have important protective properties. In this paper, we propose Cwp22 protein as a good antigen candidate for CDI preventive vaccine. Our results open the possibility to use 54 EFRVAT 59 , 201 KVNGKM 20 6 and 268 WQEKNGKKYY 277 , epitopes as suitable anti-CD vaccine antigens., Competing Interests: The authors declare no conflict of interest.

We hypothesized that selenium(Se)-enriched polysaccharides would possess superior biological activity when compared to those non-enriched. To verify this hypothesis, we obtained by biotechnological methods a Se-enriched analog of Japanese anticancer drug lentinan and, as a reference, the non-Se-enriched fraction. We tested the effects of the obtained fractions on the proliferation of human peripheral blood mononuclear cells. The results suggested a selective immunosuppressive activity, non-typical for mushroom derived polysaccharides. Both fractions caused significant inhibition of human T lymphocyte proliferation induced by mitogens, without significant effects on B lymphocytes. The inhibitory effect was not due to the toxicity of the examined polysaccharides. In normal (HUVEC) or malignant (HeLa) cells tested fractions significantly enhanced cell viability and protected the cells from oxidative stress conditions. However, we observed no effect of the polysaccharide fractions on the production of reactive oxygen species by granulocytes in vitro. The selenium content increased the biological activity of the tested polysaccharide fractions., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Pseudomonas aeruginosa is an opportunistic pathogen with a capacity to develop antibiotic resistance, which underlies a larger proportion of hospital-acquired infections and higher morbidity and mortality, compared to other bacterial infections. Effective novel approaches for treatment of infections induced by this pathogen are therefore necessary. Phage therapy represents a promising alternative solution to eradicate antibiotic-resistant pathogens. Here, we investigated phage protein efficacy against multi-drug resistant (MDR) P. aeruginosa PAR21 and PAR50 strains isolated from diabetic foot ulcer patients. The results obtained using spot assay, zymography, spectrophotometry and scanning electron microscopy at low voltage (SEM-LV) indicate that the phage protein, PA-PP, exerts activity against P. aeruginosa PAR50 while having no impact on the PAR21 strain. Using LC-MS-MS/MS and comparative analysis of the peptide molecular mass with the protein sequence database, PA-PP was identified as a member of the serine protease family, a result corroborated by its ability to digest casein. We additionally showed a capacity of PA-PP to digest porin protein on the bacterial outer membrane (OM). Moreover, synergistic activity between PA-PP protein and piperacillin led to higher sensitivity of bacterial cells to this antibiotic. Our collective findings suggest that PA-PP targets porin protein on PAR50 OM, thereby increasing its sensitivity to specific antibiotics. The adverse effects observed on bacterial cells using SEM-LV suggest further roles of this protein that remain to be established.

Objective: Pseudomonas aeruginosa effectively facilitate resistance to phagocyte killing by biofilm formation. However, the cross talk between biofilm components and phagocytes is still unclear. We hypothesize that a biofilm provides a concentrated extracellular source of LPS, DNA and exopolysaccharides (EPS), which polarize neighbouring phagocytes into an adverse hyperinflammatory state of activation., Methods: We measured the release of a panel of mediators produced in vitro by murine neutrophils and macrophages exposed to various biofilm components of P. aeruginosa cultures., Results: We found that conditioned media from a high biofilm-producing strain of P. aeruginosa, PAR5, accumulated high concentrations of extracellular bacterial LPS, DNA and EPS by 72 h. These conditioned media induced phagocytes to release a hyperinflammatory pattern of mediators, with enhanced levels of TNF-α, IL-6, IL12p40, PGE 2 and NO. Moreover, the phagocytes also upregulated COX-2 and iNOS with no influence on the expression of arginase-1., Conclusions: Phagocytes exposed to biofilm microenvironment, called by us biofilm-associated neutrophils/macrophages (BANs/BAMs), display secretory properties similar to that of N1/M1-type phagocytes. These results suggest that in vivo high concentrations of LPS and DNA, trapped in biofilm by EPS, might convert infiltrating phagocytes into cells responsible for tissue injury without direct contact with bacteria and phagocytosis.

The main objective of our research was to analyze the structure of the Se-containing polysaccharides and to examine how the selenium is bound to the polysaccharide molecule. During investigation of the biosynthesis of new immunomodulators, we isolated a selenium (Se)-containing polysaccharide-protein fraction containing proteoglycans of molecular weights of 3.9 × 10 6 Da and 2.6 × 10 5 Da, composed of glucose or mannose, nearly 8% of protein and 190 μg Se/g dry weight. X-ray absorption spectroscopy (XAS) data analysis in the near edge region (XANES) confirmed that selenium in the Se-polysaccharides structure is present at the -II oxidation state and that Se is organically bound. The simulation analysis in the EXAFS (extended X-ray absorption fine structure) region suggested that selenium is most likely bound by a glycosidic-link in a β-1,3 or α-1,4-glycosidic bond or substituted for oxygen in a pyranosidic ring. Calculations performed with Gaussian 03 software predicted deformations in the polysaccharide structure caused by the incorporation of the selenium atom including change in bond lengths and torsion angles and, as a result, disappearance of hydrogen bonds in the vicinity of the selenium atoms., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Three Streptococcus agalactiae (group B streptococci, GBS) immunoreactive proteins: enolase (47.4 kDa), inosine 5'-monophosphate dehydrogenase (IMPDH) (53 kDa) and molecular chaperone GroEL (57 kDa) were subjected to investigation. Enolase protein was described in our previous paper, whereas IMPDH and GroEL were presented for the first time. The aim of our paper was to provide mapping of specific epitopes, highly reactive with umbilical cord blood serum. Bioinformatic analyses allowed to select 32 most likely epitopes for enolase, 36 peptides for IMPDH and 41 immunoreactive peptides for molecular chaperone GroEL, which were synthesized by PEPSCAN. Ten peptides: two in enolase, one in IMPDH and seven in molecular chaperone GroEL have been identified as potentially highly selective epitopes that can be used as markers in rapid immunological diagnostic tests or constitute a component of an innovative vaccine against GBS infections.

Clostridium difficile (CD) infections are a growing threat due to the strain resistance to antibiotic treatment and the emergence of hypervirulent strains. One solution to this problem is the search for new vaccine antigens, preferably surface-localized that will be recognized by antibodies at an early stage of colonization. The purpose of the study was to assess the usefulness of novel immunoreactive surface proteins (epitopes) as potential vaccine antigens. Such approach might be tough to pursue since pathogens have acquired strategies to subvert adaptive immune response to produce humoral response against non-essential proteins for their survival. In this study CD surface proteins were isolated, immunoreactive proteins identified and mapped to select potential epitopes. The results of the study exclude the use of CD glyceraldehyde 3-phosphate dehydrogenase as a vaccine antigen, especially as a whole protein. Sequences P9 ( 201 AAGNIVPNTTGAAKAI 218 ) and P10 ( 224 KGKLDGAAQRVPVVTG 241 ) recognized by patients sera are conserved and widespread among CD strains. They show cross-reactivity with sera of people suffering from other bacterial infections and are recognized by sera of autoimmune disease patients. Our study documents that special care in analyzing the sequence of new epitope should be taken to avoid side effects prior to consider it as a vaccine antigen.

In designing a bacteria biosensor, various issues must be addressed: the specificity of bacteria recognition, the immobilization of biomolecules that act as the bacteria receptor, and the selectivity of sensor surface. The aim of this paper was to examine how the biofunctionalized surface of Ti, Au, and Ru metals reacts in contact with strains of Escherichia coli ( E . coli ) . The focus on metal surfaces results from their future use as electrodes in high frequency biosensors, e.g., resonant circuits or transmission-line sections. First, the surfaces of different metals were chemically functionalized with 3-aminopropyltriethoxysilane (APTES) and glutaraldehyde or with 3-glycidylooxypropyltrimethoxysilane (GPTMS) followed by N -(5-amino-1-carboxypentyl) iminodiacetic acid (AB-NTA) and NiCl₂. Secondly, the lipopolysaccharide binding protein (LBP), polyclonal anti- Escherichia coli antibody and bacteriophage protein gp37 were tested as bacteria receptors. The selectivity and specificity have been confirmed by the Enzyme-Linked Immunosorbent Assay (ELISA) and visualized by scanning electron microscopy at low landing energies. We noticed that LBP, polyclonal antibody, and gp37 were successfully immobilized on all studied metals and recognized the E . coli bacteria selectively. However, for the antibody, the highest reactivity was observed when Ti surface was modified, whereas the bacteria binding was comparable between LBP and gp37 on the functionalized Ru surfaces, independent from modification. Thus, all surfaces were biocompatible within the scope of biosensor functionality, with titanium functionalization showing the best performance.

Tsukamurella pulmonis is an opportunistic actinomycetal pathogen associated with a variety of rarely diagnosed human infections. In clinical cases of infection, T. pulmonis usually accompanies other bacterial pathogens. Because of these mixed infections, a robust diagnostic assay is important. The bacteria cell surface polysaccharides are considered not only useful targets for diagnostics but also intriguing subjects for analysis of the interactions that regulate the host response in general. Here, the structure of the polysaccharide component of the T. pulmonis cell wall was established. Sugar and methylation analysis and 2D-NMR techniques revealed that its polysaccharide belongs to the class of arabinomannan composed of branched tetrasaccharide repeating units, with addition of linear →6)-α-D-Manp-(1→ mannan. Rabbit polyclonal sera against T. pulmonis and T. paurometabola bacterial cells revealed cross reactivity between their antigens. Tissue samples from mice infected with T. pulmonis revealed liver abscesses and pathologic granules located intracellularly when immunohistochemically stained with monoclonal antibodies raised against T. pulmonis polysaccharide. Ultrastructural studies revealed that these granules contain T. pulmonis cells. These observations indicate that T. pulmonis is a pathogenic species capable of spreading within the organism, presumably through the blood.

The interaction between the T4 bacteriophage gp37 adhesin and the bacterial lipopolysaccharide (LPS) is a well-studied system, however, the affinity and strength of the interaction haven't been analyzed so far. Here, we use atomic force microscopy to determine the strength of the interaction between the adhesin and its receptor, namely LPS taken from a wild strain of E. coli B. As negative controls we used LPSs of E. coli O111:B and Hafnia alvei. To study the interaction an AFM tip modified with the gp37 adhesin was used to scan surfaces of mica covered with one of the three different LPSs. Using the correlation between the surface topography images and the tip-surface interaction we could verify the binding between the specific LPS and the tip in contrast to the very weak interaction between the tip and the non-binding LPSs. Using force spectroscopy we could then measure the binding strength by pulling on the AFM tip until it lifted off from the surface. The force necessary to break the interaction between gp37 and LPS from E. coli B, LPS from E. coli O111:B and LPS from H. alvei were measured to be 70 ± 29 pN, 46 ± 13 pN and 45 ± 14 pN, respectively. The latter values are likely partially due to non-specific interaction between the gp37 and the solid surface, as LPS from E. coli O111:B and LPS from H. alvei have been shown to not bind to gp37, which is confirmed by the low correlation between binding and topography for these samples.