Induction of Siglec-FhiCD101hi eosinophils in the lungs following murine hookworm Nippostrongylus brasiliensis infection

Helminth-induced eosinophils accumulate around the parasite at the site of infection, or in parasite-damaged tissues well after the helminth has left the site. The role of helminth-elicited eosinophils in mediating parasite control is complex. While they may contribute to direct parasite-killing and tissue repair, their involvement in long-term immunopathogenesis is a concern. In allergic Siglec-F^hiCD101^hi, eosinophils are associated with pathology. Research has not shown if equivalent subpopulations of eosinophils are a feature of helminth infection. In this study, we demonstrate that lung migration of rodent hookworm Nippostrongylus brasiliensis (Nb) results in a long-term expansion of distinct Siglec-F^hiCD101^hi eosinophil subpopulations. Nb-elevated eosinophil populations in the bone marrow and circulation did not present this phenotype. Siglec-F^hiCD101^hi lung eosinophils exhibited an activated morphology including nuclei hyper-segmentation and cytoplasm degranulation. Recruitment of ST2⁺ ILC2s and not CD4⁺ T cells to the lungs was associated with the expansion of Siglec-F^hiCD101^hi eosinophils. This data identifies a morphologically distinct and persistent subset of Siglec-F^hiCD101^hi lung eosinophils induced following Nb infection. These eosinophils may contribute to long-term pathology following helminth infection.

Il4ra-independent vaginal eosinophil accumulation following helminth infection exacerbates epithelial ulcerative pathology of HSV-2 infection

How helminths influence the pathogenesis of sexually transmitted viral infections is not comprehensively understood. Here, we show that an acute helminth infection (Nippostrongylus brasiliensis [Nb]) induced a type 2 immune profile in the female genital tract (FGT). This leads to heightened epithelial ulceration and pathology in subsequent herpes simplex virus (HSV)-2 infection. This was IL-5-dependent but IL-4 receptor alpha (Il4ra) independent, associated with increased FGT eosinophils, raised vaginal IL-33, and enhanced epithelial necrosis. Vaginal eosinophil accumulation was promoted by IL-33 induction following targeted vaginal epithelium damage from a papain challenge. Inhibition of IL-33 protected against Nb-exacerbated HSV-2 pathology. Eosinophil depletion reduced IL-33 release and HSV-2 ulceration in Nb-infected mice. These findings demonstrate that Nb-initiated FGT eosinophil recruitment promotes an eosinophil, IL-33, and IL-5 inflammatory circuit that enhances vaginal epithelial necrosis and pathology following HSV-2 infection. These findings identify a mechanistic framework as to how helminth infections can exacerbate viral-induced vaginal pathology.

Impact of Helminth Infections on Female Reproductive Health and Associated Diseases

A growing body of knowledge exists on the influence of helminth infections on allergies and unrelated infections in the lung and gastrointestinal (GI) mucosa. However, the bystander effects of helminth infections on the female genital mucosa and reproductive health is understudied but important considering the high prevalence of helminth exposure and sexually transmitted infections in low- and middle-income countries (LMICs). In this review, we explore current knowledge about the direct and systemic effects of helminth infections on unrelated diseases. We summarize host disease-controlling immunity of important sexually transmitted infections and introduce the limited knowledge of how helminths infections directly cause pathology to female reproductive tract (FRT), alter susceptibility to sexually transmitted infections and reproduction. We also review work by others on type 2 immunity in the FRT and hypothesize how these insights may guide future work to help understand how helminths alter FRT health.

Pre-conception maternal helminth infection transfers via nursing long-lasting cellular immunity against helminths to offspring

Maternal immune transfer is the most significant source of protection from early-life infection, but whether maternal transfer of immunity by nursing permanently alters offspring immunity is poorly understood. Here, we identify maternal immune imprinting of offspring nursed by mothers who had a pre-conception helminth infection. Nursing of pups by helminth-exposed mothers transferred protective cellular immunity to these offspring against helminth infection. Enhanced control of infection was not dependent on maternal antibody. Protection associated with systemic development of protective type 2 immunity in T helper 2 (T_H2) impaired IL-4Rα^-/- offspring. This maternally acquired immunity was maintained into maturity and required transfer (via nursing) to the offspring of maternally derived T_H2-competent CD4 T cells. Our data therefore reveal that maternal exposure to a globally prevalent source of infection before pregnancy provides long-term nursing-acquired immune benefits to offspring mediated by maternally derived pathogen-experienced lymphocytes.

Surfactant Protein-D Is Essential for Immunity to Helminth Infection

Pulmonary epithelial cell responses can enhance type 2 immunity and contribute to control of nematode infections. An important epithelial product is the collectin Surfactant Protein D (SP-D). We found that SP-D concentrations increased in the lung following Nippostrongylus brasiliensis infection; this increase was dependent on key components of the type 2 immune response. We carried out loss and gain of function studies of SP-D to establish if SP-D was required for optimal immunity to the parasite. N. brasiliensis infection of SP-D-/- mice resulted in profound impairment of host innate immunity and ability to resolve infection. Raising pulmonary SP-D levels prior to infection enhanced parasite expulsion and type 2 immune responses, including increased numbers of IL-13 producing type 2 innate lymphoid cells (ILC2), elevated expression of markers of alternative activation by alveolar macrophages (alvM) and increased production of the type 2 cytokines IL-4 and IL-13. Adoptive transfer of alvM from SP-D-treated parasite infected mice into naïve recipients enhanced immunity to N. brasiliensis. Protection was associated with selective binding by the SP-D carbohydrate recognition domain (CRD) to L4 parasites to enhance their killing by alvM. These findings are the first demonstration that the collectin SP-D is an essential component of host innate immunity to helminths.

Infections by parasitic worms are very common, and controlling them is a major medical and veterinary challenge. Very few drugs exist to treat them, and the parasites can develop resistance to these. In order to find new ways to control worm infections, understanding how our immune system responds to them is essential. Many important parasitic worm infections move through the host lung. In this study we show that a major secreted protein in the lung, Surfactant Protein D (SP-D), is essential for immunity to a parasitic worm infection. We found that this protein binds to worm larvae in the lung to help the immune system kill them. Infecting mice that do not express SP-D with worms demonstrates SP-D is important in this immune response. These mice are unable to launch an effective anti-worm immune response and have many more worms in their intestine compared to mice that do express SP-D. We also show that if we increase SP-D levels in the lung the mouse has better immunity to worms. Together this shows for the first time that SP-D is very important for immunity to worm infections.

Development of bioconjugated dye-doped poly(styrene-co-maleimide) nanoparticles as a new bioprobe

Fluorescent dye-doped poly(styrene-co-maleimide) nanoparticles were synthesised and functionalized with amine groups and avidin and the dye-loading was varied.

Operational competency development in E and F grade nursing staff: preparation for management

There is limited literature for operational management competency development in E and F grade nursing staff. These grades of nursing staff have to take over from G grade nurses ward managers on a regular basis. With human resources doing less of the operational management and taking more of an advisory role, nursing staff are now required to deal with disciplinary procedures and other management issues in a more consistent manner. Therefore, this development programme in a Scottish primary care NHS psychiatric service was designed to enable E and F grade nurses to take over from ward managers and to enable ward managers to 'succession plan' for times when they will be absent. The literature is reviewed, the background to the development programme described and the design of the development programme is explained. The results from both the pilot study (n=13) and first group (n=8) through the course are presented, evaluated discussed.

Epithelial-mesenchymal interaction and insulin-like growth factors in hyperoxic lung injury

To investigate the role of epithelial-mesenchymal interaction on oxygen-induced lung injury, we used a coculture model with lung fibroblasts (FB) embedded between 2 layers of collagen gel with and without human tracheobronchial epithelial cells (HTBE), and studied the effect of hyperoxia on the directed migration of FB towards epithelial cells and proliferation of fetal lung FB. The expression of insulin-like growth factor (IGF)-I, -II, and -IIR mRNAs and proteins was studied in FB and HTBE cells cultured separately in 95% oxygen and 5% CO2 for 48 hours. There was a significant increase in directional migration of FB in coculture with epithelial cells when exposed to 95% oxygen and 5% CO2 (P = .04 compared to cocultures without oxygen exposure). Hyperoxia stimulated the proliferation of fibroblasts cocultured with HTBE cells (0.75 +/- 0.05 x 10(6) cells per well) as compared to control (0.47 +/- 0.03 x 10(6) cells per well; P = .01). This was inhibited by anti-IGF-I antibody (69 +/- 2% of hyperoxia alone; P = .002). Western blot showed a significant increase in IGF-I protein in epithelial cells (P = .02). IGF-I mRNA was increased in HTBE cells after hyperoxia (P = .003). In conclusion, HTBE cells modulate lung FB migration and proliferation in response to hyperoxia exposure. This is mediated in part by IGF-I produced by epithelial cells.

Effect of elastase on the directional migration of lung fibroblasts within a three-dimensional collagen matrix

Interactions between airway epithelial cells and bronchial fibroblasts often require close proximity between these cells. Previous studies have demonstrated that airway epithelial cells direct the migration of lung fibroblasts, but the factors that regulate this process during airway injury are not clear. We hypothesized that exposure of culture substrates to proteolytic enzymes, like those present in the inflamed airway, would increase fibroblast recruitment. We also postulated that elastase might affect the epithelium's ability to attract fibroblasts. We used an in vitro model with fibroblasts embedded between two layers of collagen gel to investigate their migration. Embedded fibroblasts exposed to culture medium alone (baseline) had a slight downward migration (migration directed to the upper gel layer expressed as a percentage of total migration was -2.8 +/- 1.4), but medium supplemented with porcine pancreatic elastase (PPE) resulted in a slight upward migration (2.0 +/- 1.4). When airway epithelial cells were cultured on the upper gel surface, the index of directed migration toward them was 15.9 +/- 1.3. Addition of PPE to the culture medium resulted in a significant increase to 22.3 +/- 1.5 (p < .05). Human neutrophil elastase (HNE) produced similar results, and these effects were inhibited by alpha 1-proteinase inhibitor. Similarly, total fibroblasts per 20 high-powered fields were counted in all conditions, suggesting that mitogenic interactions were not important in this system. The percentage of the total fibroblasts migrating at least 5 microns in any direction was also similar in all groups, suggesting chemokinetic mechanisms were not involved. These data suggest that elastase exposure in a model of the human airway increases directed fibroblast migration through the extracellular matrix. This phenomenon may play a role in the development of subepithelial fibrosis seen in inflammatory airway diseases like asthma.

Hyperoxic exposure of developing rat lung decreases tropoelastin mRNA levels that rebound postexposure

These studies were undertaken to determine whether tropoelastin message expression in lung parenchymal tissue is altered in rats reared in an hyperoxic environment during the period of time that alveolar septation normally occurs. Rat pups were exposed to > 95% oxygen from days 4 to 14 and killed during the exposure and recovery periods. Results of in situ hybridizations indicated a delay in peak tropoelastin (TE) message levels in oxygen-exposed rats vs. controls, day 16 vs. day 11, respectively. In addition, lung parenchymal TE mRNA levels in the oxygen-exposed pups remained elevated through day 23, 1 wk after TE mRNA levels had decreased in controls. These observations suggest that the regulatory control of elastin synthesis during lung alveolar septation is altered by hyperoxic exposure. In a separate experiment, rat pups were exposed to > 95% oxygen during the period of alveolarization and followed for 4 wk postexposure. Pulmonary function measurements were conducted to determine whether lung function was altered postexposure and, if so, whether recovery occurred. We also used stereological techniques to quantitate the total length of lung parenchymal elastic fibers to determine whether elastic fiber content in the oxygen-exposed pups was restored to normal levels during the month postexposure. Although the total length of elastic fibers in lung parenchyma was found to be greater in oxygen-exposed than control pups from postnatal days 22 to 41, pressure-volume curves indicated that lungs of the oxygen-exposed pups tended to be more compliant than controls, suggesting that abnormal elastic fiber assembly might have been a contributing factor.

Radionuclide detection of gastroesophageal reflux in children suffering from recurrent lower respiratory tract infection

Radionuclide gastro-esophageal scintigraphy was performed on 25 control and 183 children suffering from recurrent lower respiratory tract infection. Gastro-esophageal reflux (GER) of varying grades was observed in 135 patients. The severity of clinical symptoms in the patients was found to be directly related to the severity of reflux observed in the radionuclide study. In some patients an attempt was also made to quantitate GER by calculating the Gastro-esophageal reflux index. The results of the scintigraphic study were correlated with the results of the other commonly used and more conventional Barium swallow and fluoroscopy study. Gastro-esophageal scintigraphy was found to be much superior in terms of sensitivity, specificity and accuracy in detecting GER. It was also possible to objectively evaluate and monitor response to treatment following conservative or corrective surgical therapy using the radionuclide technique. The results of the study demonstrated a remarkably high incidence of GER in the patients. Whether GER is the cause of recurrent lower respiratory tract infection or not is difficult to establish firmly. But within the preview of the study the association seems to be very strong and cannot be easily ignored.

Identification and partial characterization of diagnostically relevant antigens of Aspergillus fumigatus

Metabolic antigens of Aspergillus fumigatus, soil strain 2605 and sputum isolate, were evaluated for their diagnostic applicability using hyperimmune sera and sera of adults and pediatric patients of allergic bronchopulmonary aspergillosis. An indirect ELISA was standardised by using 2-10 micrograms/ml of coating antigen for detection of specific IgG and IgE antibodies in the sera of patients. The ratios of absorbance for specific IgE and IgG antibodies by ELISA (normal to patients) were observed to be in the range of 1:2 to 1:3 to 1:8 respectively. These antigenic preparations were further analyzed to identify and characterize the individual components by immunoblotting. This analysis indicated the presence of allergenic and antigenic determinants in the antigens of molecular weights 70, 34, and 28 Kd. The utility of the antigens of soil strain for diagnostic purpose is suggested.

Cryptogenic fibrosing alveolitis in children

Cryptogenic fibrosing alveolitis (CFA) in children is supposedly a rare diffuse lung disease characterized clinically by tachypnoea, cough, poor weight gain, and cyanosis. Histologically, it is characterized by thickening of alveolar walls and infiltration of the alveolar septae with mononuclear cells and fibrous tissue. The condition is more acute in children, with fulminant course. Ten children were diagnosed as having CFA out of three hundred children seen over a period of 3 years. Diagnosis was established by characteristic clinical findings and laboratory evaluation. All the children had tachypnoea at rest and bilateral crepitations in the absence of fever. Diffuse bilateral persistent irregular shadows were noted on the chest X-ray of these children. Pulmonary function studies revealed a restrictive type of abnormality with low transfer factor for carbon monoxide in six children. Open lung biopsy was done in eight children. The biopsy material was graded according to nine morphologic variables. Administration of steroids early in the course of illness resulted in amelioration of symptoms in 60% of the patients.

Allergic bronchopulmonary aspergillosis in Indian children with bronchial asthma

Out of 243 children with bronchial asthma, 107 children (44%) were found to have perennial asthma. These children were studied to determine the incidence of allergic bronchopulmonary aspergillosis (ABPA) in Indian children. Clinical and radiologic evaluations, skin testing, and precipitin studies with Aspergillus fumigatus antigen, and total IgE level estimations were done. Fifteen percent of children had four or more of the criteria, and were considered to have ABPA.