Papillary carcinoma in struma ovarii: an unusual presentation.

Struma ovarii is the presence of thyroid tissue as the major cellular component in an ovarian tumour. Papillary carcinoma in struma ovarii is exceptionally rare. We report a case of papillary carcinoma in struma ovarii in a postmenopausal 51-year-old female who initially presented clinically with hyperthyroidism. Serology, however, did not confirm hyperthyroidism. During a re-admission to our hospital later that year she appeared to have had periods of postmenopausal vaginal haemorrhage. An abdominal mass was located by radiography and pathological investigation revealed a papillary carcinoma in struma ovarii. Some striking features of this unusual presentation of importance to the internal medicine physician are discussed.

Pulmonary aspergillosis.

Aspergillus species are ubiquitous in the environment and are inevitably inhaled into the airways. Inhalation of Aspergillus conidia or mycelium fragments may result in colonisation of the airways. In susceptible hosts colonisation may subsequently cause disease. Patients with pre-existent cavities may develop aspergillomas which may be quiescent or cause symptoms especially recurrent haemoptysis. Acute invasive disease is potentially lethal in patients who are vulnerable to infection due to underlying lung diseases or immunosuppression. In addition to its ability to colonise the human respiratory tract, Aspergillus has a significant potential to act as a powerful allergen resulting in Aspergillus asthma and allergic bronchopulmonary aspergillosis. The various presentations of pulmonary disease caused by Aspergillus are reviewed here, focusing primarily on clinical aspects rather than basic science.

Protease-dependent activation of epithelial cells by fungal allergens leads to morphologic changes and cytokine production.

BACKGROUND: Proteases in extracts of Aspergillus fumigatus cause epithelial cell desquamation and release of proinflammatory cytokines. OBJECTIVE: We sought to assess protease activity in Alternaria alternata, Cladosporium herbarum, and Aspergillus fumigatus extracts and study the ability of these extracts to cause desquamation and release of proinflammatory cytokines from epithelial cells. METHODS: Protease activities of the fungal extracts were quantified. Changes with respect to cell morphology, cell desquamation, and cytokine production (IL-6 and IL-8) were measured in the absence and presence of the fungal extracts in an airway-derived epithelial cell line (A549) and primary epithelial nasal cells. RESULTS: Fungal proteases differentially induced morphologic changes, cell desquamation, and production of IL-6 and IL-8 in a dose- and time-dependent fashion. Alternaria alternata extracts induced cell shrinking and cell desquamation and strongly enhanced the production of IL-6 and IL-8 at higher concentrations. Aspergillus fumigatus extracts caused cell shrinking, cell desquamation, and production of IL-6 and IL-8, even at low concentrations. The Aspergillus fumigatus-derived extract grown on collagen medium induced a strong dose-dependent decline in cytokine production at higher concentrations. Cladosporium herbarum extracts did not induce morphologic changes or cell desquamation but enhanced IL-6 and IL-8 productions at higher concentrations. The dependence of these effects on intact protease activity was shown by their abrogation by protease inhibitors. CONCLUSION: Proteases present in fungal extracts interact with epithelial cells, leading to morphologic changes, cell desquamation, and induction of proinflammatory cytokines. It is proposed that these fungal proteases may activate epithelial cells through a protease-activated receptor type 2-driven mechanism.

Putative virulence factors of Aspergillus fumigatus.

Various putative virulence factors of Aspergillus fumigatus have been studied over the past decades. A. fumigatus gliotoxin is a potent inhibitor of the mucociliary system. Several fungal metabolites interfere with phagocytosis and opsonization including toxins, 'conidial inhibitory factor', 'A. fumigatus diffusible product' and 'complement inhibitory factor'. A. fumigatus can bind specifically to different host tissues components, whereas toxins give a general and significant immunosuppressive effect on host defences. Circumstantial evidence links the production of elastinolytic proteases with the ability to cause disease. However, none of the reports demonstrates conclusively a decisive role for any of the virulence factors described thus far. It is conceivable that proteolytic enzyme activities such as those expressed by AFAlp are one of a number of factors, each with a minor effect, that combine to facilitate disease progression.

Proteases from Aspergillus fumigatus induce interleukin (IL)-6 and IL-8 production in airway epithelial cell lines by transcriptional mechanisms.

Proteases secreted by Aspergillus fumigatus induce the production of cytokines by epithelial cells, including interleukin (IL)-6 and IL-8. In the present study, we focused on the mechanism(s) by which A. fumigatus-derived proteases elicit cytokine production in epithelial cells. In the epithelial cell line A549, IL-6 and IL-8 mRNA levels were enhanced by proteases as a result of transcriptional induction of the respective genes. Transcriptional induction of both genes coincided with enhanced DNA binding of nuclear factor (NF)-kappaB and NF-IL6, whereas activator protein-1 was unlikely to be involved. The enhanced transcriptional activity could be inhibited by the addition of chymostatin, showing serine protease dependency. Posttranscriptional mechanisms affecting the stability of IL-6 and IL-8 mRNAs were not involved in protease-induced IL-6 and IL-8 production. These data show that after exposure to A. fumigatus-derived proteases, IL-6 and IL-8 gene expressions are up-regulated as a result of transcriptional mechanisms.

Interactions between inhalant allergen extracts and airway epithelial cells: effect on cytokine production and cell detachment.

BACKGROUND: The factors responsible for inducing or maintaining airway inflammation are poorly understood. Various studies have focussed on the mechanisms leading to allergic airway inflammation in patients with asthma and rhinitis. The observation of local airway inflammation in nonallergic patients with asthma or rhinitis, including those with nasal polyposis, suggest that non-IgE-related mechanisms exist that may lead to airway inflammation. Various lines of evidence suggest that epithelial cells may participate in local inflammation of the airways. OBJECTIVE: This study focused on the interaction of airway epithelial cells with clinically relevant inhalant allergen extracts in vitro. METHODS: Cultures of airway epithelial cells were exposed to mite, Timothy grass pollen, and birch pollen extracts. Production of IL-8, IL-6, monocyte-chemotactic protein-1 (MCP-1), and granulocyte-macrophage colony-stimulating factor and cell detachment were monitored while protease inhibitors and chromatography techniques were applied to identify the factors responsible for these effects. RESULTS: With the mite extracts, cytokine production and cell detachment was largely dependent on protease activity. With the pollen extracts, cytokine production without cell detachment seemed to be independent of protease activity. CONCLUSION: These findings support the view that epithelial cells may contribute to the pathogenesis of airway disease by their interaction with inhalant allergen extracts. Furthermore, allergen extracts may enhance airway inflammation by means other than their IgE-binding activity through both protease-dependent and protease-independent mechanisms.

Secretory leukoprotease inhibitor: a native antimicrobial protein presenting a new therapeutic option?

Secretory leukoprotease inhibitor (SLPI) is a low molecular weight serine protease inhibitor found on various mucosal surfaces and has been ascribed an important role in maintaining the protease-anti-protease balance of the airways. Recent scientific evidence has suggested that SLPI may also have a broad spectrum antibiotic activity that includes antiretroviral, bactericidal, and antifungal activity. Given the unpropitious development of drug resistance to infectious micro-organisms in the human population, the need for therapeutic alternatives in the treatment of infectious diseases has become clear. SLPI may prove valuable in the prophylaxis and future treatment of infectious diseases, yet the clinical efficacy of SLPI remains largely to be elucidated.

Antileukoprotease: an endogenous protein in the innate mucosal defense against fungi.

Previous studies have suggested that endogenous protease inhibitors may participate in the mucosal host defense. Antileukoprotease (ALP) is an important protease inhibitor found on various mucosal surfaces, including those of the respiratory and genital tracts. This study reports on the antimicrobial activity of recombinant (r) ALP toward the human fungal pathogens Aspergillus fumigatus and Candida albicans. rALP expressed pronounced fungicidal activity toward metabolically active A. fumigatus conidia and C. albicans yeast cells; however, metabolically quiescent A. fumigatus conidia were totally resistant. In contrast with the protease inhibitory activity of rALP, the fungicidal activity was localized primarily in the NH2-terminal domain. On a molar base, the fungicidal activity of rALP was comparable with that of human defensins and lysozyme. In addition, rALP caused inhibition of C. albicans yeast cell growth. By exhibiting antifungal activity, ALP may play an important role in the innate mucosal defense against human pathogenic fungi.

Proteases from Aspergillus fumigatus induce release of proinflammatory cytokines and cell detachment in airway epithelial cell lines.

Aspergillus fumigatus is a pathogen causing diverse respiratory disorders. Several studies have suggested that fungal proteases may play a role in the pathogenicity of fungi. Since the airways are the most common route for entry of A. fumigatus, this study focused on the ability of fungal proteases to induce the release of proinflammatory cytokines and to cause cell detachment in human pulmonary epithelial cell lines. It was shown that fungal serine protease activity induced the production of interleukin (IL)-8 and IL-6 and monocyte chemotactic protein-1 and caused cell detachment in a dose-dependent fashion. Chymostatin, antipain, phenylmethylsulfonyl fluoride, and heat treatment completely inhibited fungal protease activity, cytokine production and cell detachment; antileukoprotease partially inhibited these activities. By causing cell detachment, fungal proteases may decrease the physical barrier function of the epithelium; however, by eliciting a cytokine response, the epithelium may signal the mucosal inflammatory response against A. fumigatus.

Serodiagnosis and monitoring of Aspergillus infections after lung transplantation.

OBJECTIVE: To determine whether quantification of specific antifungal antibody responses in serum can provide supplemental information for the diagnosis of Aspergillus fumigatus infections and the monitoring of antifungal treatment in patients after lung transplantation. DESIGN: Retrospective study. SETTING: Center for lung transplantation, University Hospital Groningen, the Netherlands. PATIENTS: 4 patients with proven A. fumigatus infections after lung transplantation and fatal outcome. MEASUREMENTS: The IgG antibody response specific for A. fumigatus antigens was measured by enzyme-linked immunosorbent assay and was compared with radiographic features, cytologic findings, microbiological cultures, and clinical diagnosis. RESULTS: Increasing IgG antibody responses specific for A. fumigatus antigens closely paralleled cytologic or microbiological identification of A. fumigatus from bronchoalveolar lavage fluid and decrease of lung function. Increasing specific IgG antibody responses were found to precede radiographic identification of lung cavitation by 1 to 2 weeks, precede the diagnosis of aspergillosis by 2 to 20 weeks, and detect fungal reinfection. In most cases, successful antifungal treatment decreased specific IgG antibody response. A decrease in specific IgG antibody response correlated with the inability to culture or identify A. fumigatus in bronchoalveolar lavage fluid and with radiographic and clinical improvement. CONCLUSIONS: Specific IgG antibody responses in serum correlate with radiographic, cytologic, and microbiological findings and with the clinical diagnosis of A. fumigatus infections in patients who have had lung transplantation. Increased IgG antibody responses in serum may provide important information that is helpful in the diagnosis and early treatment of pulmonary fungal infections and in monitoring antifungal treatment.

Specific IgG4 responses during chronic and transient antigen exposure in aspergillosis.

The factors that lead to increased production of specific IgG subclasses are still largely unknown. Recent studies suggest that increased IgG4 responses may be related to prolonged antigen exposure. We present data showing that increased IgG4 responses are found under conditions of chronic exposure to Aspergillus fumigatus (Af) antigen. IgG(total), IgG subclass, and IgE responses were studied using ELISA, CAP-FEIA, and immunoblotting techniques in patients with pulmonary aspergilloma (PA), which is a model for chronic antigen exposure, and allergic bronchopulmonary aspergillosis (ABPA), characterized by transient antigen exposure. Af-IgG1 was increased in patients with PA compared with those with ABPA. Patients with PA and IgE responses to Af and/or other inhalant allergens showed significantly higher Af-IgG4 responses than did patients with PA and negative IgE responses or patients with ABPA. Surveillance studies over time in individual patients showed concordance in Af-IgG1 and Af-IgG4 responses. Both Af-IgG1 and Af-IgG4 levels followed the course of disease progression and treatment. Immunoblotting revealed correlations between Af-IgG1 and Af-IgG4 binding to most, but not all, antigenic Af components. This study documents for the first time increased IgG4 levels under conditions of chronic exposure to fungal antigen in PA. Furthermore, a significantly higher IgG4 response was found in those patients with PA who produced IgE. The transient exposure to Af antigen during exacerbation of ABPA gives rise to transient elevations in IgG4 levels.

Liposomes as an immunoadjuvant system for stimulation of mucosal and systemic antibody responses against inactivated measles virus administered intranasally to mice.

This paper reports on the immune-stimulatory activity of liposomes in an inactivated whole measles virus vaccine preparation administered intranasally to mice. Liposomes, simply mixed with inactivated whole measles virus, significantly stimulated the serum IgG response relative to the response to the virus alone. In addition, the liposomal vaccine, but not the free virus, induced a secretory IgA (s-IgA) response in the lungs and nasal cavity. Serum IgG and s-IgA responses persisted up to at least 24 weeks post-immunization. The liposomes induced a moderate increase in the serum IgG response, but no s-IgA response, following intramuscular immunization. It is concluded that liposomes provide a promising adjuvant system for induction of high systemic as well as mucosal antibody responses against inactivated measles virus in an intranasal or inhalation vaccine formulation.

Review of fungus-induced asthmatic reactions.

Fungus-induced obstructive airway disease in atopic individuals can be differentiated into two categories: first, uncomplicated asthmatic reactions due to high but transient exposure to fungal spores (fungal asthma), resulting in a TH2-type response with immunoglobulin E-mediated reactions and eosinophilic inflammation; and second, a more complex asthmatic reaction due to colonization of the mucus-epithelial surface by virulent protease-producing fungi. The latter condition stimulates as exaggerated immunological response including all subclasses of antibodies directed against the microorganism and an intense eosinophilic infiltrate of the airways. The authors propose that the exaggerated inflammatory response in allergic bronchopulmonary fungosis damages epithelial cells and underlying tissue cells, resulting in inefficient elimination of the microorganisms and damage to matrix proteins of the lung tissue by proteases released by both the fungi and degranulating eosinophils. The positive effects of corticosteroids in the treatment of allergic bronchopulmonary aspergillosis probably results from the dampening of the inflammatory response and an increase of the efficiency of killing the fungi. Sensitization to fungi is high in childhood and declines rapidly with age, suggesting that younger children may be less proficient in clearing fungi from the airways. We propose that insufficient treatment of fungal asthma may result in damage to the bronchial mucosa and formation of bronchiectasis.

Serologic monitoring of disease and treatment in a patient with pulmonary aspergilloma.

Disease progression and efficacy of fungistatic treatment in pulmonary aspergilloma (PA) are difficult to monitor. The usefulness of chest tomography, IgG-ELISA serology, double immunodiffusion, and IgG-immunoblotting was assessed in monitoring disease progression and efficacy of itraconazole treatment during a 9-yr follow-up of a patient with two exacerbations of PA. A rise in IgG-ELISA titer coincided with a recrudescence of clinical symptoms, whereas a decrease after treatment paralleled clinical improvement. IgG-binding to a 32-kD serine protease and to 60- and 94-kD proteins produced with collagen-containing culture medium closely corresponded with IgG-ELISA titers. IgG-binding to a 40-kD metalloprotease remained at very low levels until symptoms and fungal growth became well advanced, when a sharp rise was seen. Responses to all antigens rapidly diminished after the start of successful treatment with itraconazole. Serology may be a useful adjunct in the monitoring of disease progression and the efficacy of itraconazole treatment in patients with PA. IgG-binding to individual fungal proteins shows subtle differences in kinetics. Immunologic responses to fungal proteases raised with collagen-containing culture media may reflect fungal proteolytic involvement during disease progression and treatment more closely than responses to proteins raised with conventional media.

Immunologic significance of a collagen-derived culture filtrate containing proteolytic activity in Aspergillus-related diseases.

BACKGROUND: Despite increasing evidence implicating fungal proteases in the virulence of pulmonary fungal diseases, routine fungal culture media do not favor protease production. Hence, filtrates that serve as the source of antigen for serologic determinations are poor in proteases, and consequently, the immunologic significance of these enzymes is unknown. METHODS: A clinical isolate of Aspergillus fumigatus was cultured on collagen medium, resulting in excretion of high levels of fungal proteases in the culture filtrate. This was compared with standard culture filtrates by diverse analytic techniques including immunoblotting with sera of patients with pulmonary aspergilloma (PA) and allergic bronchopulmonary aspergillosis (ABPA). RESULTS: Protein profiles of collagen medium filtrate showed several (glyco)proteins not found in conventional culture filtrates, including a prominent 32 kd glycoprotein, which coisolated in gel filtration and ion-exchange chromatography with elastase activity, as well as 67 kd and 94 kd (glyco)proteins. Intense IgG binding was seen with the 32 kd glycoprotein when ABPA and PA sera were used. The 94 kd protein showed intense binding with PA sera but not with ABPA sera, whereas for the 67 kd glycoprotein the reverse tended to be the case. CONCLUSION: Fungal culture on collagen media results in the production of filtrates with high protease activity, containing unique (glyco)proteins of which at least one (32 kd) is closely associated with fungal elastase activity. These constituents are immunologically relevant, eliciting IgG production in patients with PA and ABPA, suggesting production of these (glyco)proteins during disease in vivo. The use of collagen media filtrates may enhance our serodiagnostic capacity in patients with fungal pulmonary diseases.