Dustborne Alternaria alternata antigens in US homes: results from the National Survey of Lead and Allergens in Housing.

National Institute of Environmental Health Sciences, National Institutes of Health, Research Triangle Park, NC 27709, USA.
Journal of Allergy and Clinical Immunology (Impact Factor: 11.25). 10/2005; 116(3):623-9. DOI: 10.1016/j.jaci.2005.05.030
Source: PubMed

ABSTRACT Alternaria alternata is one of the most common fungi associated with allergic disease. However, Alternaria exposure in indoor environments is not well characterized.
The primary goals of this study were to examine the prevalence of Alternaria exposure and identify independent predictors of Alternaria antigen concentrations in US homes.
Data for this cross-sectional study were obtained from the National Survey of Lead and Allergens in Housing. A nationally representative sample of 831 housing units in 75 different locations throughout the United States completed the survey. Information on housing and household characteristics was obtained by questionnaire and environmental assessments. Concentrations of A alternata antigens in dust collected from various indoor sites were assessed with a polyclonal anti-Alternaria antibody assay.
Alternaria antigens were detected in most (95% to 99%) of the dust samples. The geometric mean concentration, reflecting the average Alternaria concentration in homes, was 4.88 microg/g (SEM, 0.13 microg/g). In the multivariable linear regression analysis, the age of the housing unit, geographic region, urbanization, poverty, family race, observed mold and moisture problems, use of de-humidifier, and presence of cats and dogs were independent predictors of Alternaria antigen concentrations. Less frequent cleaning and smoking indoors also contributed to higher Alternaria antigen levels in homes.
Exposure to A alternata antigens in US homes is common. Antigen levels in homes are influenced not only by regional factors but also by residential characteristics. Preventing mold and moisture problems, avoiding smoking indoors, and regular household cleaning may help reduce exposure to Alternaria antigens indoors.

Download full-text


Available from: Richard D Cohn, Apr 08, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Allergies affect almost 25% of the population in industrialized countries. Alternaria alternata is known to be a significant source of aeroallergens and sensitization to this mold is a risk factor for the development of wheezing, asthma, and atopic dermatitis. Diagnosis and treatment of allergies requires the production of large amounts of pure and well defined protein. Yarrowia lipolytica, a non-pathogenic ascomycete able to secrete high levels of enzymes that can grow in inexpensive substrates, has been considered a useful host for heterologous gene expression. In the present work, we have developed two vectors for expressing Alt a 1, the most relevant A. alternata allergen, in Y. lipolytica. One vector is autosomal and one is integrative. With both systems, rAlt a 1 was secreted into the culture medium. The immunological characteristics of the purified recombinant allergen were determined by IgE-blot using sera from 42 A. alternata-allergic patients. We have carried out ELISA-inhibition experiments using sera from four patients to compare the IgE-binding capacity of natural and recombinant allergens. Our results show that Y. lipolytica is able to produce a recombinant Alt a 1 which is immunochemically equivalent to the natural counterpart and could be used for immunotherapy and diagnostics.
    FEMS Microbiology Letters 05/2012; 333(2):121-8. DOI:10.1111/j.1574-6968.2012.02606.x · 2.72 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Assessment of the health effects of indoor moulds is complicated by the diversity of mould species found in homes and the limitations of current methods to determine exposure. Thus it is difficult to establish whether there is a relationship between mould exposure and disease. Allergic respiratory diseases are commonly caused by Alternaria, Aspergillus, Cladosporium and Penicillium spp. IgE-mediated sensitization to these moulds is a strong risk factor for asthma: IgG and IgE antibody responses to Aspergillus fumigatus are common in patients with other respiratory diseases, including allergic bronchopulmonary aspergillosis and cystic fibrosis. Several important mould allergens have been cloned with different biologic functions. These allergens can also serve as immunologic markers which may be associated with disease activity. Evidence for health effects associated with exposure to mould toxins e.g. from Stachybotrys spp. is less compelling. Recently, several new technolgies have been introduced which could be applied to mould exposure assessment. Ion-charging devices can silently sample air within homes and have been successfully used to monitor animal allergens. Fluorescent multiplex array technology is being used to make quantitative measurements of five to ten allergens simultaneously on dust samples. The development of monospecific (monoclonal or polyclonal) antibodies to specific fungal antigens or allergens will facilitate more accurate assessments of the mould burden in homes, schools and commercial buildings. The application of these techniques in well-designed clinical studies will enable better understanding of the health effects of moulds
  • Source