W. Elliott Horner

Exposure and Health Effects of Fungi on Humans

Fungi are ubiquitous microorganisms that are present in outdoor and indoor environments. Previous research has found relationships between environmental fungal exposures and human health effects. We reviewed recent articles focused on fungal exposure and dampness as risk factors for respiratory disease development, symptoms, and hypersensitivity. In particular, we reviewed the evidence suggesting that early exposure to dampness or fungi is associated with the development of asthma and increased asthma morbidity. Although outdoor exposure to high concentrations of spores can cause health effects such as asthma attacks in association with thunderstorms, most people appear to be relatively unaffected unless they are sensitized to specific genera. Indoor exposure and dampness, however, appears to be associated with an increased risk of developing asthma in young children and asthma morbidity in individuals who have asthma. These are important issues because they provide a rationale for interventions that might be considered for homes and buildings in which there is increased fungal exposure. In addition to rhinitis and asthma, fungus exposure is associated with a number of other illnesses including allergic bronchopulmonary mycoses, allergic fungal sinusitis, and hypersensitivity pneumonitis. Additional research is necessary to establish causality and evaluate interventions for fungal- and dampness-related health effects.

Guide for interpreting reports from inspections/investigations of indoor mold

Inspections and testing of indoor environments for mold growth increased dramatically in the past decade. Allergists can now be presented copies of reports and laboratory data and asked to provide an interpretation, although allergists are seldom trained to review environmental data. There is no single sampling method that is both specific for mold growth and robust enough to reliably detect mold growth. There is no standard method for these inspections or testing and no widely recognized credential for investigators, and therefore reports also vary in quality, objectives, and thoroughness. Despite these issues, observations from informed inspections coupled with results from qualified analyses of samples that are collected with a useful strategy can usually indicate whether mold growth is present in a building, but the nature of the report should be assessed before any interpretation of the results and data are attempted. This rostrum discusses objectives of inspections, describes qualifications for investigators, outlines the limitations of various sampling methods applicable to mold and to some degree endotoxin, and provides guidance for data interpretation.

Evidence for cross-reactive allergens among basidiomycetes: immunoprint-inhibition studies.

Allergenic cross-reactivity among six basidiomycete species (Calvatia cyathiformis, Coprinus quadrifidus, Psilocybe cubensis, Pleurotus ostreatus, Ganoderma meredithae, and Pisolithus tinctorius) was determined by immunoprint inhibition. Extensive cross-reactivity was demonstrated among Coprinus quadrifidus, Psilocybe cubensis, and Pleurotus ostreatus of the order Agaricales, and Calvatia cyathiformis of the order Lycoperdales. However, G. meredithae (order Aphyllophorales) and Pisolithus tinctorius (order Sclerodermatales) did not demonstrate significant cross-reactivity with the other basidiomycete species. Generally, the two most potent inhibitors were Psilocybe cubensis and Pleurotus ostreatus. Inhibitory dose-response curves of a major allergenic band (isoelectric point, 9.3) were obtained by densitometry. Significant cross-reactivity was demonstrated for the 9.3 band among the species of the order Agaricales and with Calvatia cyathiformis. The most potent inhibitors were again Psilocybe cubensis and Pleurotus ostreatus. Thus, there is substantial allergenic cross-reactivity among the species of the order Agaricales tested and with Calvatia cyathiformis but not between these four species and G. meredithae or Pisolithus tinctorius. These studies support earlier RAST-inhibition observations of shared allergenic epitopes among basidiomycetes, especially epitopes within the Agaricales. The presence of shared epitopes suggests the possibility of devising a panel of skin test reagents representative of a large group of basidiomycetes.

Innate and Adaptive Immune Response to Fungal Products and Allergens

Exposure to fungi and their products is practically ubiquitous, yet most of this is of little consequence to most healthy individuals. This is because there are a number of elaborate mechanisms to deal with these exposures. Most of these mechanisms are designed to recognize and neutralize such exposures. However, in understanding these mechanisms it has become clear that many of them overlap with our ability to respond to disruptions in tissue function caused by trauma or deterioration. These responses involve the innate and adaptive immune systems usually through the activation of nuclear factor kappa B and the production of cytokines that are considered inflammatory accompanied by other factors that can moderate these reactivities. Depending on different genetic backgrounds and the extent of activation of these mechanisms, various pathologies with resulting symptoms can ensue. Complicating this is the fact that these mechanisms can bias toward type 2 innate and adaptive immune responses. Thus, to understand what we refer to as allergens from fungal sources, we must first understand how they influence these innate mechanisms. In doing so it has become clear that many of the proteins that are described as fungal allergens are essentially homologues of our own proteins that signal or cause tissue disruptions.

Procedures to Assist Health Care Providers to Determine When Home Assessments for Potential Mold Exposure Are Warranted.

Drawing evidence from epidemiology and exposure assessment studies and recommendations from expert practice, we describe a process to guide health care providers helping their patients who present with symptoms that might be associated with living in damp housing. We present the procedures in the form of a guided 2-part interview. The first part has 5 questions that triage the patient toward a more detailed questionnaire that reflects features of housing conditions known to be reliably associated with exposures to mold and dampness contaminants. We chose the questions based on the conditions associated with moisture problems in homes across the United States and Canada. The goal is to facilitate the clinicians effort to help patients reduce exposure to environmental triggers that elicit symptoms to better manage their disease.

Home Assessment and Remediation

Awareness of the relationship of fungi to asthma in indoor air is very old and well documented. There is substantial evidence that mold and dampness exacerbate asthma in sensitized individuals. Many governmental and nongovernmental organizations around the world have issued guidelines to the effect that the elimination of moisture intrusion and the removal of moldy items from living space can improve respiratory health. The process of home assessment for moisture and mold presence is discussed along with factors that can be used to guide fungal exposure reduction efforts. An approach to the assessment process itself is outlined, and common causes of moisture and mold damage are described. Points that should be included in a report resulting from a home assessment and rudimentary elements of report interpretation are discussed. Emphasis is that interpretation of sampling for moisture and fungal presence should be provided by the person performing the assessment. We conclude that multifaceted remediation contributes to fungal allergen avoidance. The use of an indoor environmental professional to generate evaluation reports and remediation activities can be a valuable contribution to an overall allergen avoidance strategy.

Cockroach allergenic activity: Analysis of commercial cockroach and dust extracts

Previous investigations demonstrated that cockroach whole bodies and feces are important sources of allergens in the induction/exacerbation of bronchial asthma. The current study investigated different cockroach source materials, commercial extracts, and house dust extracts for cockroach allergenic activity. In general, extracts from four different sources of either American or German cockroaches contained similar amounts of allergenic activity by RAST inhibition. Three commercial American cockroach extracts compared by RAST inhibition had similar allergenic activity on an equal protein basis. Skin test results correlated house dust reactivity to both commercial and inhouse cockroach wholebody extracts and to fecal extracts. Six different samples of house dust obtained from vacuum cleaners in the New Orleans area and three commercially obtained house dust extracts contained varying quantities of cockroach allergenic activity by RAST inhibition. These studies demonstrate that commercial cockroach extracts vary in allergenic activity and that all house dust extracts tested contain cockroach allergens.

MORPHOLOGY AND ALLERGENIC PROPERTIES OF BASIDIOSPORES FROM FOUR CALVATIA SPECIES

Basidiospores of Calvatia cyathiformis have been identified in aerobiological studies, and spore extracts have demonstrated significant skin and radioallergosorbent test reactivity in sensitive patients. Although fruiting bodies of Calvatia craniiformis, C. rubroflava, and C. gigantea are also relatively common, basidiospores of these species cannot be specifically identified from the atmosphere. The present study compared the morphology and antigenic properties of basidiospores from these four Calvatia species. Electron microscopy showed that they all have globose spores 3-5 ,tm in diameter but each species has unique spore ornamentation. Only C. cyathiformis spores were sufficiently distinctive by light microscopy to be identifiable on air sampler slides. These spores occurred in the Tulsa atmosphere on 68% of the days during September and October. The allergenic properties were compared using radioallergosorbent and radioallergosorbent test inhibition. Results indicate that C. rubroflava and C. craniiformis are potentially important aeroallergens. Protein patterns in these species differed from one another and from C. cyathiformis; however, common proteins were also present. Spore extracts of C. cyathiformis from two states were similar by isoelectric focusing but differed in allergenic activity. C. gigantea gave indiscernible protein patterns. These studies indicate that although Calvatia species demonstrate a number of similarities, there are distinctive structural and allergenic properties.

Quantitation of specific igg, iga, and igm antibodies directed against four species of basidiomycetes

Abstract Specific IgG, IgA, and IgM antibodies to aqueous extracts of Coprinus quadrifidus, Pleurotus ostreatus, Calvatia cyathiformis, and Psilocybe cubensis were assessed using an enzyme linked immunosorbent assay (ELISA) in basidiomycete radioallergosorbent test (RAST) positive atopics (Gr 1), RAST negative atopics (Gr 2), and RAST negative, non-atopics (Gr 3). ELISA values are presented as mean optical density ± sem. For C. quadrifidus, elevated specific IgA levels (0.33 ± 0.08, p=0.02) were shown in Gr 1, as compared with Gr 2 (0.129 ± 0.04) and Gr 3 (0.163 ± 0.02). For P. ostreatus, specific IgA levels (0.534 ± 0.15) were also elevated (p=0.003) in Gr 1, when compared with Gr 2 (0.389 ± 0.01) and Gr 3 (0.121 ± 0.03). For C. cyathiformis and P. cubensis, specific IgA levels in Gr 1 were higher than those in Gr 2 and Gr 3, however, these were not significantly elevated. For P. cubensis, specific IgM levels were elevated (p=0.03) in Gr 2 (0.666 ± 0.081) when compared with Gr 1 (0.505 ± 0.056) and Gr 3 ...

Landscape Plant Selection Criteria for the Allergic Patient

Patients with pollen-related allergies are concerned about the species within their landscape that provoke their symptoms. Allergists are often asked for guidance but few information sources are available to aid patients in the recognition of allergenic plants and strategies to avoid personal exposure to them. Landscaping and horticultural workers also have few reliable guidance references, and what is available usually extols the virtues of the plants rather than their negative features. The aim of this article was to provide the results of the Landscape Allergen Working Group that was formed by the AAAAI Aerobiology Committee, which aimed to fill these existing knowledge gaps and develop guidance on producing a low-allergenic landscape. Within the context that complete pollen avoidance is unrealistic, the workgroup introduces selection criteria, avoidance strategies, and guidance on low-allergenic plants that could be selected by patients to reduce the overall pollen burden in their landscape environment. Specific focus is placed on entomophilous plants, which require insects as dispersal vectors and generally produce lower quantities of pollen, compared with anemophilous (wind-pollinated) species. Other biological hazards that can be encountered while performing landscaping activities are additionally reviewed and avoidance methods presented with the aim of protecting gardeners, and workers in the landscape and horticulture industries. The guidance presented in this article will ultimately be a helpful resource for the allergist and assist in engaging patients who are seeking to reduce the burden of allergen in their landscape environment.