Cathelicidin Treatment Silences Epithelial-Mesenchymal Transition Involved in Pulmonary Fibrosis in a Murine Model of Hypersensitivity Pneumonitis.

Pulmonary fibrosis is becoming an increasingly common pathology worldwide. Unfortunately, this disorder is characterized by a bad prognosis: no treatment is known, and the survival rate is dramatically low. One of the most frequent reasons for pulmonary fibrosis is hypersensitivity pneumonitis (HP). As the main mechanism of pulmonary fibrosis is a pathology of the repair of wounded pulmonary epithelium with a pivotal role in epithelial-mesenchymal transition (EMT), we assumed that EMT silencing could prevent disease development. Because of several biological features including wound healing promotion, an ideal candidate for use in the treatment of pulmonary fibrosis seems to be cathelicidin. The aim of the studies was to understand the influence of cathelicidin on the EMT process occurring during lung fibrosis development in the course of HP. Cathelicidin's impact on EMT was examined in a murine model of HP, wherein lung fibrosis was induced by chronic exposure to extract of Pantoea agglomerans (SE-PA) by real-time PCR and Western blotting. Studies revealed that mouse exposure to cathelicidin did not cause any side changes in the expression of investigated genes/proteins. Simultaneously, cathelicidin administered together or after SE-PA decreased the elevated level of myofibroblast markers (Acta2/α-smooth muscle actin, Cdh2/N-cadherin, Fn1/Fibronectin, Vim/vimentin) and increased the lowered level of epithelial markers (Cdh1/E-cadherin, Ocln/occludin). Cathelicidin provided with SE-PA or after cessation of SE-PA inhalations reduced the expression of EMT-associated factors (Ctnnd1/ß-catenin, Nfkb1/NFκB, Snail1/Snail, Tgfb1/TGFß1 Zeb1/ZEB1, Zeb2/ZEB2) elevated by P. agglomerans. Cathelicidin's beneficial impact on the expression of genes/proteins involved in EMT was observed during and after the HP development; however, cathelicidin was not able to completely neutralize the negative changes. Nevertheless, significant EMT silencing in response to cathelicidin suggested the possibility of its use in the prevention/treatment of pulmonary fibrosis.

A Scoping Analysis of Cathelicidin in Response to Organic Dust Exposure and Related Chronic Lung Illnesses.

Over two billion people worldwide are exposed to organic dust, which can cause respiratory disorders. The discovery of the cathelicidin peptide provides novel insights into the lung's response to organic dust; however, its role in the lung's response to organic dust exposure and chronic lung diseases remains limited. We conducted a scoping review to map the current evidence on the role of cathelicidin LL-37/CRAMP in response to organic dust exposure and related chronic lung diseases: hypersensitivity pneumonitis (HP), chronic obstructive pulmonary disease (COPD) and asthma. We included a total of n = 53 peer-reviewed articles in this review, following the process of (i) a preliminary screening; (ii) a systematic MEDLINE/PubMed database search; (iii) title, abstract and full-text screening; (iv) data extraction and charting. Cathelicidin levels were shown to be altered in all clinical settings investigated; its pleiotropic function was confirmed. It was found that cathelicidin contributes to maintaining homeostasis and participates in lung injury response and repair, in addition to exerting a positive effect against microbial load and infections. In addition, LL-37 was found to sustain continuous inflammation, increase mucus formation and inhibit microorganisms and corticosteroids. In addition, studies investigated cathelicidin as a treatment modality, such as cathelicidin inhalation in experimental HP, which had positive effects. However, the primary focus of the included articles was on LL-37's antibacterial effect, leading to the conclusion that the beneficial LL-37 activity has not been adequately examined and that further research is required.

Pantoea agglomerans chronic exposure induces epithelial-mesenchymal transition in human lung epithelial cells and mice lungs.

Pantoea agglomerans is gram-negative bacteria widely distributed in nature. It predominates in inhalable dust from grain, herbs, and flax, and was identified as the most important cause of hypersensitivity pneumonitis (HP) in eastern Poland. To better understand the molecular mechanism of HP development studies focused on the interactions between P. agglomerans and alveolar epithelial cells as well as lung tissue with particular emphasis on the epithelial-mesenchymal transition (EMT). The studies were conducted on human normal lung epithelial NL20 cells and mice strain C57BL/6J. Cells and mice underwent chronic exposure to saline extract of P. agglomerans (SE-PA). Morphological changes were evaluated under light microscopy, the concentration of fibrosis markers was examined by the ELISA method, while the expression of genes involved in EMT was evaluated by RealTime PCR. During incubation with SE-PA epithelial cells underwent conversion and assumed fibroblast phenotype characterized by a decrease in epithelial cells markers (CDH1, CLDN1, JUP) and increase in mesenchymal cells markers (FN1, VIM, CDH2). Mice lungs collected after 14 days of SE-PA treatment revealed inflammation with marked lymphocytes infiltration. The intensified inflammatory process accompanied by increased proliferation of fibrous connective tissue was noted in mice lungs after 28 days of SE-PA exposure. Histological changes correlated with an increase of fibrosis markers (hydroxyproline, collagens), downregulation of epithelial markers (Cdh1, Cldn1, Jup, Ocln) and upregulation of myofibroblasts markers (Acta2, Cdh2, Fn1, Vim). Obtained results revealed SE-PA ability to induce EMT in human lung epithelial cells and mice lung tissue, with the scale of changes proportional to the time of treatment.

Middle age enhances expression of innate immunity genes in a female mouse model of pulmonary fibrosis.

The lungs are highly sensitive to tissue fibrosis, with a clear age-related component. Among the possible triggers of pulmonary fibrosis are repeated inhalations of fine organic particles. How age affects this response, is still far from being fully understood. We examined the impact of middle-age on gene expression in pulmonary fibrosis, using the novel "inhalation challenge set" mouse model. Our results demonstrate that the response of female mice to exposure of Pantoea agglomerans extract primarily involves various immune-related pathways and cell-cell/cell-extracellular matrix interactions. We found that middle-age had a strong effect on the response to the P. agglomerans-induced lung fibrosis, featured by a more rapid response and increased magnitude of expression changes. Genes belonging to innate immunity pathways (such as the TLR signaling and the NK-cell mediated cytotoxicity) were particularly up-regulated in middle-aged animals, suggesting that they may be potential targets for the treatment of pulmonary fibrosis caused by inhalations of organic particles. Our analysis also highlights the relevance of the "inhalation challenge set" mouse model to lung aging and related pathology.

The RESOLVE concept: approaching pathophysiology of fibroproliferative disease in aged individuals.

After reaching adulthood, orderly repair is probably one of the most important mechanisms throughout lifetime. Regular wound healing after an injury consists of a well-ordered sequence of overlapping phases of repair and essentially repeats the complex process of organ development. Organ failure in the ageing organism frequently represents the lost capacity to achieve an orderly reactivation of organ development, yet in varying and complex pathologic settings. One of the most aggressive manifestations of age-dependent and dysbalanced wound healing is a disease called idiopathic pulmonary fibrosis. Essentially, the disease replaces functional lung tissue with spreading scar tissue over a period of just 5 years. By a systematic comparison of wound healing conditions, the large-scale collaborative FP7-EU project RESOLVE has addressed these difficulties in a successful way. Background and outlining of the project are discussed.

Age influence on hypersensitivity pneumonitis induced in mice by exposure to Pantoea agglomerans.

Hypersensitivity pneumonitis (HP) represents the immunologically mediated lung disease induced by repeated inhalations of a wide variety of certain finely dispersed organic antigens. In susceptible subjects, these inhalations provoke a hypersensitivity reaction characterized by intense inflammation of the terminal bronchioles, the interstitium and the alveolar tree. The inflammation often organizes into granulomas and may progress to pulmonary fibrosis. Our previous work indicated that cell extract of gram-negative bacteria Pantoea agglomerans (SE-PA) causes, in young C57BL/6J mice, pulmonary changes that are very similar to the clinical manifestations of HP in men. The purpose of presented studies was to describe the response of mice immune system while exposed to SE-PA. Particular attention was paid to examine the age influence on SE-PA induced inflammation and fibrosis in lung tissue. We used 3- and 18-month-old C57BL/6J mice. Lung samples were collected from untreated mice and animals exposed to harmful agent for 7 and 28 days. HP development was monitored by histological and biochemical evaluation. Using ELISA tests, we examined concentration of pro- and anti-inflammatory cytokines in lung homogenates. Our study demonstrated again that SE-PA provokes in mice changes typical for the clinical picture of HP, and that successive stages of disease (acute, subacute and chronic) might be obtained by modulation of time exposure. Furthermore, we found that animals' age at the time of sensitization influences the nature of observed changes (cytokine expression pattern) and the final outcome (reaction intensity and scale of fibrosis).

Comprehensive Ontology of Fibroproliferative Diseases: Protocol for a Semantic Technology Study.

BACKGROUND: Fibroproliferative or fibrotic diseases (FDs), which represent a significant proportion of age-related pathologies and account for over 40% of mortality in developed nations, are often underrepresented in focused research. Typically, these conditions are studied individually, such as chronic obstructive pulmonary disease or idiopathic pulmonary fibrosis (IPF), rather than as a collective entity, thereby limiting the holistic understanding and development of effective treatments. To address this, we propose creating and publicizing a comprehensive fibroproliferative disease ontology (FDO) to unify the understanding of FDs. OBJECTIVE: This paper aims to delineate the study protocol for the creation of the FDO, foster transparency and high quality standards during its development, and subsequently promote its use once it becomes publicly available. METHODS: We aim to establish an ontology encapsulating the broad spectrum of FDs, constructed in the Web Ontology Language format using the Protégé ontology editor, adhering to ontology development life cycle principles. The modeling process will leverage Protégé in accordance with a methodologically defined process, involving targeted scoping reviews of MEDLINE and PubMed information, expert knowledge, and an ontology development process. A hybrid top-down and bottom-up strategy will guide the identification of core concepts and relations, conducted by a team of domain experts based on systematic iterations of scientific literature reviews. RESULTS: The result will be an exhaustive FDO accommodating a wide variety of crucial biomedical concepts, augmented with synonyms, definitions, and references. The FDO aims to encapsulate diverse perspectives on the FD domain, including those of clinicians, health informaticians, medical researchers, and public health experts. CONCLUSIONS: The FDO is expected to stimulate broader and more in-depth FD research by enabling reasoning, inference, and the identification of relationships between concepts for application in multiple contexts, such as developing specialized software, fostering research communities, and enhancing domain comprehension. A common vocabulary and understanding of relationships among medical professionals could potentially expedite scientific progress and the discovery of innovative solutions. The publicly available FDO will form the foundation for future research, technological advancements, and public health initiatives. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): PRR1-10.2196/48645.

Beneficial impact of cathelicidin on hypersensitivity pneumonitis treatment-In vivo studies.

Cathelicidin (CRAMP) is a defence peptide with a wide range of biological responses including antimicrobial, immunomodulatory and wound healing. Due to its original properties the usefulness of CRAMP in the treatment of pulmonary fibrosis was assessed in a murine model of hypersensitivity pneumonitis (HP). The studies were conducted on mouse strain C57BL/6J exposed to a saline extract of Pantoea agglomerans cells (HP inducer). Cathelicidin was administered in the form of an aerosol during and after HP development. Changes in the composition of immune cell populations (NK cells, macrophages, lymphocytes: Tc, Th, Treg, B), were monitored in lung tissue by flow cytometry. Extracellular matrix deposition (collagens, hydroxyproline), the concentration of cytokines involved in inflammatory and the fibrosis process (IFNγ, TNFα, TGFß1, IL1ß, IL4, IL5, IL10, IL12α, IL13) were examined in lung homogenates by the ELISA method. Alterations in lung tissue morphology were examined in mouse lung sections stained with haematoxylin and eosin as well as Masson trichrome dyes. The performed studies revealed that cathelicidin did not cause any negative changes in lung morphology/structure, immune cell composition or cytokines production. At the same time, CRAMP attenuated the immune reaction induced by mice chronic exposure to P. agglomerans and inhibited hydroxyproline and collagen deposition in the lung tissue of mice treated with bacteria extract. The beneficial effect of CRAMP on HP treatment was associated with restoring the balance in quantity of immune cells, cytokines production and synthesis of extracellular matrix components. The presented study suggests the usefulness of cathelicidin in preventing lung fibrosis; however, cathelicidin was not able to reverse pathological changes completely.

Assessment of gene transcription demonstrates connection with the clinical course of idiopathic interstitial pneumonia.

BACKGROUND: Mediators of preferably mesenchymal repair such as transforming growth factor beta(1) (TGF-beta(1)) and mediators of polarized cellular immunity such as interleukin (IL)-13 are thought to be of key importance for progression of lung fibrosis. Nonetheless, a correlation between these mediators and the clinical development of fibrosis has not been performed thus far. OBJECTIVES: We correlated the transcription of TGF-beta(1), connective tissue growth factor (CTGF), IL-4, IL-13 and interferon-gamma (IFN-gamma) with lung function development in progressive fibrosis in idiopathic interstitial pneumonia. METHODS: One hundred seventy nine sets of RT-PCR measurements were analyzed in 49 patients with usual interstitial pneumonia, nonspecific interstitial pneumonia or both. Specimens were taken by surgical and transbronchial lung biopsy. Lung function was measured at the time of biopsy and 1 year later. All patients received conventional treatment. Thirteen individuals were used as controls. RESULTS: Transcription of TGF-beta(1), CTGF and IL-13 was significantly higher in pulmonary fibrosis compared to control, whereas transcription of IFN-gamma and IL-4 was virtually absent in both normal and fibrotic lungs. When comparing gene transcription with development of lung function, a significant correlation was observed between the decrease in both vital capacity and total lung capacity and increased transcription levels of TGF-beta(1) and IL-13. A reduced pulmonary diffusion capacity correlated with increased levels of TGF-beta(1) and CTGF. Transcription pattern in transbronchial and surgical samples was similar. CONCLUSIONS: We found a significant correlation between gene transcription and decrease in lung function that was more pronounced for TGF-beta(1) than for CTGF or IL-13. Our results suggest that transcription analysis may be used in clinical assessment of pulmonary fibrosis.

Cathelicidin LL-37: LPS-neutralizing, pleiotropic peptide.

Human organism, constantly exposed to a large variety of pathogenic microorganisms and their products, such as lipopolysaccharide (LPS), developed innate immunity as a first line of defence. One of the compartments of our organism well equipped with these defence mechanisms is the respiratory system. The cells lining the airways respond to the presence of virulent microorganisms by producing natural antimicrobial peptides, including the only member of the cathelicidins family found to date in humans, peptide LL-37. LL-37 is a small peptide of 37 amino acid residues. The peptide, in addition to its bactericidal effect, plays numerous roles in inflammatory and tissue remodelling processes. It stimulates angiogenesis, induces proliferation of lung epithelial cells, accelerates wound closure of the airway epithelium, and provokes cytokine release (e.g. IL-8) and cell migration. LL-37 is also able to neutralize LPS, a heteropolymer associated with organic dust, produced by Gram-negative bacteria. LPS (commonly referred to as endotoxin) plays an important role in pathogenesis of many respiratory diseases caused by organic dust, including organic dust toxic syndrome and chronic illnesses such as chronic obstructive pulmonary disease (COPD), asthma or allergic alveolitis (hypersensitivity pneumonitis). LPS is a strong pro-inflammatory stimulus, inducing in respiratory airways expression of antimicrobial peptides, including LL-37, which is in turn a potent LPS-neutralizing factor. The article discusses the complex interplay between endotoxin and the LPS-neutralizing, pleiotropic peptide LL-37 in pathogenic mechanisms of lung diseases, with regard to closer perspectives of using LL-37 and its derivatives as therapeutic agents.

Health effects of exposure to organic dust in workers of a modern hatchery.

The aim of the presented study was to determine the health status of workers occupationally exposed to moderate amounts of organic dust, employed in a modern hatchery with an efficient ventilation system. A group of 32 hatchery workers was examined. As a reference group, 50 urban dwellers not exposed to any kind of organic dust were examined. All people were interviewed for the presence of work-related symptoms and subjected to physical and spirometric examinations. Blood sera were examined for the presence of precipitins against 13 antigens associated with organic dust, and for the presence of total and chicken-specific No significant differences were found between the spirometric values in the group of hatchery workers and the reference group. Positive precipitin reactions were noted mostly with the antigens of Gram-negative bacteria associated with organic dust. The frequencies of positive reactions to antigens of Escherichia coli and Acinetobacter baumannii in hatchery workers were significantly greater compared to the reference group (p<0.05). Precipitin reactions to Gram-positive non-branching bacteria, actinomycetes, fungi and birdactions to antigens of Escherichia coli and Acinetobacter baumannii in hatchery workers were significantly greater compared to the reference group (p<0.05). Precipitin reactions to Gram-positive non-branching bacteria, actinomycetes, fungi and bird protein, were rare or absent. The mean concentration of total IgE in sera of hatchery workers was nearly 3 times greater compared to the reference group, and the difference proved to be statistically significant (p<0.05). No specific IgE antibodies against chicken feathers were detected in the blood of hatchery workers and referents. In conclusion, the examined hatchery workers showed a moderate frequency of work-related symptoms, no decline in lung function and low reactivity to most microbial and bird protein allergens. These results suggest that the effects of exposure to organic dust in workers of modern hatcheries with an efficient ventilation system are less compared to the workers of poultry farms, such as broiler or egg laying houses.

[Interstitial lung diseases--problem of ageing societies]. / Sródmiazszowe choroby pluc i zwlóknienie pluc--problem starzejacych sie spoleczenstw.

Chronic lung diseases are on increase mainly in developed countries that are characteristic by ageing societies. Despite this, interstitial lung diseases, together with lung fibrosis, seemed to be forgotten by researchers and clinicians till last years. Sufficient epidemiological data are lacking (especially little is known on the environmental and occupational causative factors). No effective treatment is available so far - diagnostic and therapeutic options available nowadays are characterized by high costs (e.g. lung transplantation) and low effectiveness. The average age of patients first diagnosed with lung fibrosis is 61 +/- 0,7 years, which poses a rising public health problem of ageing societies, especially those in Europe, USA and Japan. The average duration of life after the diagnosis is only 3 years. Facing these facts, a new approach to this group of diseases is urgently needed. A first step should include thorough epidemiological studies aimed at identification of causes and risk factors of these diseases. Results of such research should be subsequently transferred into health policy. Especially needed are sensitive screening programs and development of effective treatment that would substantially improve life expectancy and quality of life of the affected people.

Risk factors for work-related eczema and urticaria among vocational students of agriculture.

INTRODUCTION AND OBJECTIVE: Farmers are at high risk of occupational skin diseases which may start already during vocational training. This study was aimed at identification of risk factors for work-related skin diseases among vocational students of agriculture. MATERIAL AND METHODS: The study involved 440 students (245 males, 195 females aged 17-21 years) in 11 vocational schools which were at least 100 km from each other. The protocol included a physician-managed questionnaire and medical examination, skin prick tests, patch tests, total IgE and Phadiatop. Logistic regression model was used for the identification of relevant risk factors. RESULTS: Work-related dermatoses were diagnosed in 29 study participants (6.6%, 95%CI: 4.3-8.9%): eczema in 22, urticaria in 14, and co-existence of both in 7 students. Significant risk factors for work-related eczema were: history of respiratory allergy (OR=10.10; p<0.001), history of eczema (itchy rash) provoked by wet work and detergents before entering the school (OR=5.85; p<0.001), as well as history of contact dermatitis to metals, rubber or cosmetics prior to inscription (OR=2.84; p=0.016), and family history of any skin disease (OR=2.99; p=0.013). Significant risk factors for work-related urticaria were: history of allergic rhinitis and asthma prior to inscription (OR=7.29; p=0.006), positive skin prick tests to work place allergens (OR=4.65; p=0.002) and to environmental allergens (OR=3.79; p=0.009), and positive Phadiatop test (OR=3.61; p=0.013). CONCLUSIONS: Work-related skin diseases are common among vocational students of agriculture. Atopy, past history of asthma, allergic rhinitis, and eczema (either atopic, allergic or irritant) are relevant risk factors for work-related eczema and urticaria in young farmers, along with family history of any skin disease. Positive skin prick tests seem relevant, especially in the case of urticaria. Asking simple, aimed questions during health checks while enrolling students into agricultural schools would suffice to identify students at risk for work-related eczema and urticaria, giving them the chance for selecting a safer profession, and hopefully avoiding an occupational disease in the future.

Pantoea agglomerans: a mysterious bacterium of evil and good. Part III. Deleterious effects: infections of humans, animals and plants.

Pantoea agglomerans, a bacterium associated with plants, is not an obligate infectious agent in humans. However, it could be a cause of opportunistic human infections, mostly by wound infection with plant material, or as a hospital-acquired infection, mostly in immunocompromised individuals. Wound infection with P. agglomerans usually follow piercing or laceration of skin with a plant thorn, wooden splinter or other plant material and subsequent inoculation of the plant-residing bacteria, mostly during performing of agricultural occupations and gardening, or children playing. Septic arthritis or synovitis appears as a common clinical outcome of exogenous infection with P. agglomerans, others include endophthalmitis, periostitis, endocarditis and osteomyelitis. Another major reason for clinical infection with P. agglomerans is exposure of hospitalized, often immunodeficient individuals to medical equipment or fluids contaminated with this bacterium. Epidemics of nosocomial septicemia with fatal cases have been described in several countries, both in adult and paediatric patients. In most cases, however, the clinical course of the hospital-acquired disease was mild and application of the proper antibiotic treatment led to full recovery. Compared to humans, there are only few reports on infectious diseases caused by Pantoea agglomerans in vertebrate animals. This species has been identified as a possible cause of equine abortion and placentitis and a haemorrhagic disease in dolphin fish (Coryphaena hippurus). P. agglomerans strains occur commonly, usually as symbionts, in insects and other arthropods. Pantoea agglomerans usually occurs in plants as an epi- or endophytic symbiont, often as mutualist. Nevertheless, this species has also also been identified as a cause of diseases in a range of cultivable plants, such as cotton, sweet onion, rice, maize, sorghum, bamboo, walnut, an ornamental plant called Chinese taro (Alocasia cucullata), and a grass called onion couch (Arrhenatherum elatius). Some plant-pathogenic strains of P. agglomerans are tumourigenic, inducing gall formation on table beet, an ornamental plant gypsophila (Gypsophila paniculata), wisteria, Douglas-fir and cranberry. Recently, a Pantoea species closely related to P. agglomerans has been identified as a cause of bacterial blight disease in the edible mushroom Pleurotus eryngii cultivated in China. The genetically governed determinants of plant pathogenicity in Pantoea agglomerans include such mechanisms as the hypersensitive response and pathogenicity (hrp) system, phytohormones, the quorum-sensing (QS) feedback system and type III secretion system (T3SS) injecting the effector proteins into the cytosol of a plant cell.

Pantoea agglomerans: a mysterious bacterium of evil and good. Part IV. Beneficial effects.

Pantoea agglomerans, a gammaproteobacterium of plant origin, possesses many beneficial traits that could be used for the prevention and/or treatment of human and animal diseases, combating plant pathogens, promotion of plant growth and bioremediation of the environment. It produces a number of antibiotics (herbicolin, pantocins, microcin, agglomerins, andrimid, phenazine, among others) which could be used for combating plant, animal and human pathogens or for food preservation. Japanese researchers have demonstrated that the low-molecular-mass lipopolysaccharide of P. agglomerans isolated by them and described as 'Immunopotentiator from Pantoea agglomerans 1 (IP-PA1)' reveals the extremely wide spectrum of healing properties, mainly due to its ability for the maintenance of homeostasis by macrophage activation. IP-PA1 was proved to be effective in the prevention and treatment of a broad range of human and animal disorders, such as tumours, hyperlipidaemia, diabetes, ulcer, various infectious diseases, atopic allergy and stress-induced immunosuppression; it also showed a strong analgesic effect. It is important that most of these effects could be achieved by the safe oral administration of IP-PA1. Taking into account that P. agglomerans occurs commonly as a symbiont of many species of insects, including mosquitoes transmitting the Plasmodium parasites causing malaria, successful attempts were made to apply the strategy of paratransgenesis, in which bacterial symbionts are genetically engineered to express and secrete anti-Plasmodium effector proteins. This strategy shows prospects for a successful eradication of malaria, a deadly disease killing annually over one million people, as well as of other vector-borne diseases of humans, animals and plants. Pantoea agglomerans has been identified as an antagonist of many plant pathogens belonging to bacteria and fungi, as a result of antibiotic production, competition mechanisms or induction of plant resistance. Its use as a biocontrol agent permits the decrease of pesticide doses, being a healthy and environmental-friendly procedure. The application of the preparations of this bacterium efficiently protects the stored pome, stone and citrus fruits against invasion of moulds. P. agglomerans strains associated with both rhizosphere and plant tissues (as endophytes) efficiently promote the growth of many plants, including rice and wheat, which are the staple food for the majority of mankind. The promotion mechanisms are diverse and include fixation of atmospheric nitrogen, production of phytohormones, as well as degradation of phytate and phosphate solubilizing which makes the soil phosphorus available for plants. Accordingly, P. agglomerans is regarded as an ideal candidate for an environmental-friendly bioinoculant replacing chemical fertilizers. It has been documented that the Pantoea strains show biodegradation activity on various chemical pollutants of soil and water, including petroleum hydrocarbons and toxic metals. P. agglomerans prevents the penetration of harmful industrial contaminants into deeper parts of soil by biofilm formation, and has an ability to produce hydrogen from waste. Thus, this bacterium appears as a valuable bioremediator which, in some cases, may be acquired as a cheap form of energy. In conclusion, in spite of the proven pathologic role of P. agglomerans in causing occupational diseases of allergic and/or immunotoxic background and accidental infections, the beneficial traits of this species, and of related species of Pantoea genus, are of great value for potential use in many areas of biotechnology. Hence, any restrictions on the use of these organisms and their products should be declined, providing safety precautions at work with the Pantoea biopreparations are maintained.

Pantoea agglomerans: a mysterious bacterium of evil and good. Part II--Deleterious effects: Dust-borne endotoxins and allergens--focus on grain dust, other agricultural dusts and wood dust.

Pantoea agglomerans, a Gram-negative bacterium developing in a variety of plants as epiphyte or endophyte is particularly common in grain and grain dust, and has been identified by an interdisciplinary group from Lublin, eastern Poland, as a causative agent of work-related diseases associated with exposure to grain dust and other agricultural dusts. The concentration of P. agglomerans in grain as well as in the settled grain and flour dust was found to be high, ranging from 10(4)-10(8) CFU/g, while in the air polluted with grain or flour dust it ranged from 10(3)-10(5) CFU/m(3) and formed 73.2-96% of the total airborne Gram-negative bacteria. The concentration of P. agglomerans was also relatively high in the air of the facilities processing herbs and other plant materials, while it was lower in animal farms and in wood processing facilities. Pantoea agglomerans produces a biologically-potent endotoxin (cell wall lipopolysaccharide, LPS). The significant part of this endotoxin occurs in dusts in the form of virus-sized globular nanoparticles measuring 10-50 nm that could be described as the 'endotoxin super-macromolecules'. A highly significant relationship was found (R=0.804, P=0.000927) between the concentration of the viable P. agglomerans in the air of various agricultural and wood industry settings and the concentration of bacterial endotoxin in the air, as assessed by the Limulus test. Although this result may be interfered by the presence of endotoxin produced by other Gram-negative species, it unequivocally suggests the primary role of the P. agglomerans endotoxin as an adverse agent in the agricultural working environment, causing toxic pneumonitis (ODTS). Numerous experiments by the inhalation exposure of animals to various extracts of P. agglomerans strains isolated from grain dust, including endotoxin isolated with trichloroacetic acid (LPS-TCA), endotoxin nanoparticles isolated in sucrose gradient (VECN), and mixture of proteins and endotoxin obtained by extraction of bacterial mass in saline (CA-S), showed the ability of these extracts to evoke inflammatory and fibrotic changes in the lungs, to stimulate alveolar macrophages to produce superoxide anion (O2(-)), interleukin-1 (IL-1) and chemotactic factors for other macrophages and neutrophils, and to increase the pulmonary concentrations of toll-like receptors and chemokines. The most potent properties showed the CA-S which may be attributed to the allergenic properties of P. agglomerans proteins enhanced by the presence of the autologous endotoxin. The results of these experiments are in accord with the clinical studies which revealed a high reactivity of the agricultural and grain industry workers to allergenic extracts of P. agglomerans, and the presence in these populations of hypersensitivity pneumonitis and asthma cases caused by this bacterium. P. agglomerans has been also identified as a potential causative agent of allergic dermatitis in farmers and of allergic pulmonary disorders in cattle. In conclusion, similar to the cotton industry, also in the grain industry and in agriculture, Pantoea agglomerans should be regarded as one of the major causative agents of work-related diseases, caused by the adverse effects of protein allergens and endotoxin produced by this bacterium.

Health effects of exposure to herb dust in valerian growing farmers.

The aim of the present study was to determine the health status of farmers cultivating valerian (Valeriana officinalis L.) and occupationally exposed to dust from this plant. A group of 75 valerian growing farmers were examined. As a reference group, 50 urban dwellers, not exposed to any kind of organic dust were examined. All people were interviewed for the presence of work-related symptoms and subjected to physical and spirometric examinations. Skin prick tests were conducted with 4 microbial antigens associated with organic dust and 3 herbal extracts, precipitin tests with 12 microbial antigens and 4 herbal extracts and tests for specific inhibition of leukocyte migration with 4 microbial antigens. 30.7 % of the valerian farmers reported occurrence of work-related symptoms. No significant differences were found between the spirometric values in the group of valerian farmers and the reference group. Valerian farmers showed a low frequency of positive skin reactions to all tested antigens (0-4.0 %), not significantly greater compared to reference group. The frequency of positive precipitin reactions to the antigen of Gram-negative bacterium Pantoea agglomerans was very high in valerian farmers (45.5 %) with 3-fold concentrated sera and significantly greater compared to the reference group (p < 0.001). The positive precipitin response of valerian farmers to other microbial and herbal antigens was much lower or absent and did not show any difference compared to reference group. In the test for specific inhibition of leukocyte migration, the highest frequencies of positive reactions in valerian farmers were noted with Pantoea agglomerans and Saccharopolyspora rectivirgula (15.0 % each), in both cases significantly greater compared to reference group (p < 0.05). In conclusion, the farmers growing valerian showed a moderate frequency of work-related symptoms and low reactivity to most microbial and herbal allergens. They exhibited an increased immunologic response to Gram-negative bacterium Pantoea agglomerans which appears to be the most important risk factor associated with valerian dust.

Respiratory effects of exposure to dust from herbs.

A group of 150 people occupationally exposed to dust from herbs were examined. As a reference group, 50 urban dwellers, not exposed to any kind of organic dust were examined. People were subjected to routine physical examination and to lung function examinations with the LUNGTEST 500 spirometer (MES, Kraków, Poland). The spirometric values of the forced expiratory volume in one second (FEV (1)), vital capacity (VC) and FEV(1)/VC were recorded before and after work. Physical chest examination revealed pathological crepitations in 10 people (6.7 %). The mean baseline spirometric values in the study and reference groups did not show significant differences compared to the normal values. In the herb workers exposed to organic dust the post-shift decrease of all analysed spirometric values was noted. The post-shift decrease of some spirometric values (VC, VC % of normal values) was highly significant (p < 0.01). There was evidenced of a significant positive correlation between the age of examined people and decrease of VC and FEV(1) values. In 12 exposed workers the decrease of FEV(1) or FEV(1) % of normal values higher than 15 % was noted. 50 % of these workers cultivated thyme (Thymus vulgaris L.). This may suggest that dust from herbs, especially thyme dust, may cause acute airway obstruction. In the group showing significant decrease of FEV(1)/FEV(1) % of normal values ( > 15 %) the frequency of reported respiratory work-related symptoms (83.3 %) was higher than in the rest of exposed group (61.5 %). In conclusion, occupational exposure to dust from herbs may cause harmful effects on the respiratory system among herb processing workers. This indicates the need for use of prophylactic measures in this professional group, the more so as number of people occupationally exposed to dust from herbs is growing.

Pantoea agglomerans: a marvelous bacterium of evil and good.Part I. Deleterious effects: Dust-borne endotoxins and allergens - focus on cotton dust.

The ubiquitous Gram-negative bacterium Pantoea agglomerans (synonyms: Enterobacter agglomerans, Erwinia herbicola) is known both as an epiphytic microbe developing on the surface of plants and as an endophytic organism living inside the plants. The bacterium occurs also abundantly in plant and animal products, in the body of arthropods and other animals, in water, soil, dust and air, and occasionally in humans. From the human viewpoint, the role of this organism is ambiguous, both deleterious and beneficial: on one side it causes disorders in people exposed to inhalation of organic dusts and diseases of crops, and on the other side it produces substances effective in the treatment of cancer and other diseases of humans and animals, suppresses the development of various plant pathogens, promotes plant growth, and appears as a potentially efficient biofertilizer and bioremediator. P. agglomerans was identified as a predominant bacterium on cotton plant grown all over the world, usually as an epiphyte, rarely as pathogen. It is particularly numerous on cotton bract after senescence. During processing of cotton in mills, bacteria and their products are released with cotton dust into air and are inhaled by workers, causing respiratory and general disorders, usually defined as byssinosis. The most adverse substance is endotoxin, a heteropolymer macromolecule present in the outermost part of the cell wall, consisting of lipopolysaccharide (LPS) as a major constituent, phospholipids and protein. The numerous experiments carried out in last quarter of XXth century on laboratory animals and human volunteers supported a convincing evidence that the inhaled endotoxin produced by P. agglomerans causes numerous pathologic effects similar to those elicited by cotton dust, such as influx of free lung cells into airways and activation of alveolar macrophages which secrete mediators (prostaglandins, platelet-activating factor, interleukin-1, tumor necrosis factor) that cause accumulation of platelets in pulmonary capillaries initiating an acute and chronic inflammation resulting in endothelial cell damage and extravasation of cells and fluids into the lung interstitium. These changes cause bronchoconstriction, the decrement of lung function expressed as reduction of forced expiratory volume in one second (FEV1) and/or diffusion capacity, increase in the airway hyperreactivity and subjective symptoms such as fever, airway irritation and chest tightness. The conclusions from these experiments, performed mostly 2-3 decades ago, did not loose their actuality until recently as so far no other cotton dust component was identified as a more important work-related hazard than bacterial endotoxin. Though also other microbial and plant constituents are considered as potential causative agents of byssinosis, the endotoxin produced by Pantoea agglomerans and other Gram-negative bacteria present in cotton dust is still regarded as a major cause of this mysterious disease.

Age influence on mice lung tissue response to Aspergillus fumigatus chronic exposure.

INTRODUCTION AND OBJECTIVE: Exposure to conidia of Aspergillus fumigatus was described as a causative factor of a number of the respiratory system diseases, including asthma, chronic eosinophilic pneumonia, hypersensitivity pneumonitis and bronchopulmonary aspergillosis. The study investigates the effects of the repeated exposure to A. fumigatus in mice pulmonary compartment. Our work tackles two, so far insufficiently addressed, important aspects of interaction between affected organism and A. fumigatus: 1) recurrent character of exposure (characteristic for pathomechanism of the abovementioned disease states) and 2) impact of aging, potentially important for the differentiation response to an antigen. MATERIALS AND METHODS: In order to dissect alterations of the immune system involved with both aging and chronic exposure to A. fumigatus, we used 3- and 18-month-old C57BL/6J mice exposed to repeated A. fumigatus inhalations for 7 and 28 days. Changes in lung tissue were monitored by histological and biochemical evaluation. Concentration of pro- and anti-inflammatory cytokines in lung homogenates was assessed by ELISA tests. RESULTS AND CONCLUSIONS: Our study demonstrated that chronic inflammation in pulmonary compartment, characterized by the significant increase of proinflammatory cytokines (IL1, IL6, IL10) levels, was the dominant feature of mice response to repeated A. fumigatus inhalations. The pattern of cytokines' profile in the course of exposure was similar in both age groups, however in old mice the growth of the cytokines' levels was more pronounced (especially in case of IL1).