New evidence of the involvement of Lichtheimia corymbifera in farmer's lung disease.

Farmer's lung disease (FLD) is a form of hypersensitivity pneumonitis resulting from recurrent exposure to moldy plant materials. We investigated and compared the initial response of respiratory epithelium after exposure to extracts of Sacharopolyspora rectivirgula, Lichtheimia corymbifera (formerly Absidia corymbifera), Eurotium amstelodami and Wallemia sebi. The two criteria for selection of these species were their high prevalence in the hay handled by FLD patients and the presence of high levels of specific precipitins to these molds in FLD patients’ sera. Hydrosoluble extracts were prepared from spores and hyphae grown in culture under optimal conditions for each of the four species. Confluent A549 cells were inoculated with one of the four calibrated soluble extracts. Two mediators, one inflammatory (Interleukin (IL)-8) and one allergic (IL-13), were quantified using real-time PCR and ELISA assay, after four exposure periods (30 min, 2 h, 4 h and 8 h). S. rectivirgula and L. corymbifera extracts were the only ones which induced a marked upregulation of IL-8, as shown by both real-time PCR and ELISA assay 8 h after the initial contact. This study adds to the growing body of evidence that L. corymbifera should be recognized as an etiologic agent of FLD along with S. rectivirgula.

Th17-polarized immune response in a murine model of hypersensitivity pneumonitis and lung fibrosis.

Hypersensitivity pneumonitis is an environmental lung disease characterized by a diffuse mononuclear cell infiltrate in the lung that can progress to pulmonary fibrosis with chronic exposure to an inhaled Ag. Using a well-established murine model of hypersensitivity pneumonitis, we repeatedly exposed C57BL/6 mice to Saccharopolyspora rectivirgula to investigate whether T cells are required for lung fibrosis. In the absence of alphabeta T cells, TCRbeta(-/-) mice exposed to S. rectivirgula for 4 wk had markedly decreased mononuclear infiltrates and collagen deposition in the lung compared with wild-type C57BL/6 mice. In contrast to CD8(+) T cells, adoptive transfer of CD4(+) T cells reconstituted the S. rectivirgula-induced inflammatory and fibrotic response, suggesting that the CD4(+) T cell represents the critical alphabeta T cell subset. Cytokine analysis of lung homogenates at various time points after S. rectivirgula exposure failed to identify a predominant Th1 or Th2 phenotype. Conversely, IL-17 was found in the lung at increasing concentrations with continued exposure to S. rectivirgula. Intracellular cytokine staining revealed that 14% of CD4(+) T cells from the lung of mice treated with S. rectivirgula expressed IL-17A. In the absence of IL-17 receptor signaling, Il17ra(-/-) mice had significantly decreased lung inflammation and fibrosis compared with wild-type C57BL/6 mice. These data are the first to demonstrate an important role for Th17-polarized CD4(+) T lymphocytes in the immune response directed against S. rectivirgula in this murine model of hypersensitivity pneumonitis and pulmonary fibrosis.

Polymorphisms in the CD14 gene associated with pulmonary function in farmers.

RATIONALE AND OBJECTIVES: Farmers experience airway obstruction, which may be attributable in part to endotoxin inhalation. CD14 is a receptor for endotoxin. MATERIALS AND METHODS: Based on our findings of increased circulating CD14 associated with the CD14/-159 T allele, we hypothesized that carriers of this allele would have decreased lung function among endotoxin-exposed individuals. CD14/-159TT farmers (n = 19) had significantly lower lung function as measured by FEV1 (p = 0.028) and mean forced expiratory flow during the middle half of the FVC (FEF25-75) (p = 0.05) compared with farmers with the C allele (n = 78). Also, farmers with the CD14/-1619GG genotype (n =11) were associated with lower lung function (FEV1, p = 0.008; FEF25-75, p = 0.009) compared with farmers with the A allele (n = 86). RESULTS: No association between CD14/-550 and lung function was observed (FEV1, p = 0.32; FEF25-75, p = 0.11). Increased prevalence of wheezing was reported in farmers homozygous for CD14/-159T (p = 0.013) or CD14/-1619G (p = 0.019) compared with farmers with the CC or AA genotype, respectively. No association was found between TLR4/Asp299Gly and lung function or wheeze. CONCLUSION: We conclude that the CD14/-159 or CD14/-1619 loci may play a role in modulating lung function and wheeze among agricultural workers.

[Farmer's lung cases of a farmer and his son with high BAL fluid beta-D glucan levels].

A farmer and his son, who treated straw in a cowshed, were admitted to our hospital because of severe dyspnea during summer time. Their chest X-ray films revealed bilateral reticulonodular shadows in the middle to lower lung fields. Bronchoalveolar lavage (BAL) fluid analyses showed a high proportion of lymphocytes and an increased CD4/8 ratio. They were diagnosed with farmer's lung and treated with pulse therapy with methylprednisolone and tapering of steroid. Hypoxemia and interstitial shadow improved, though the farmer relapsed one day after getting home. Immune precipitation showed positive reactions against Aspergillus fumigatus, Aspergillus terreus and Nocardiopsis alba. Their beta D-glucan levels in BAL fluid were higher than those of healthy normal volunteers, whereas their beta D-glucan levels in serum were below the detection levels. Ventilation of the cowshed and wearing a mask should prevent recurrence of the disease.

Tumor necrosis factor-alpha -308 promoter gene polymorphism and increased tumor necrosis factor serum bioactivity in farmer's lung patients.

Hypersensitivity pneumonitis (HP) represents an immunologic reaction of the pulmonary parenchyma to an inhaled agent. Since tumor necrosis factor (TNF)-alpha is thought to be involved in the pathogenesis of HP, and polymorphisms in the TNF genes have been associated with variations in the production of TNF-alpha, we investigated the serum bioactivity and genotype of TNF in HP. TNF bioactivity was measured after hay dust challenge in eight patients with farmer's lung (Group A) and in 12 healthy, sensitized (antibody-positive) controls (Group B). Genotyping for the -308 TNF-alpha promoter polymorphism and the TNF-beta intron 1 gene polymorphism was performed in 20 patients with farmer's lung, 25 patients with pigeon breeder's lung, and 216 controls. TNF bioactivity increased in Group A at 4 to 10 h after hay dust challenge, but not in Group B (p < 0.05). The frequency for the TNFA2 allele, a genotype associated with high TNF-alpha production in vitro, was significantly higher in farmer's lung patients (frequency [f] = 0.43, p = 0.0012) than in controls (f = 0.19) or patients with pigeon breeder's lung (f = 0.16). Genotyping for TNF-beta revealed no significant abnormalities. Thus, increased production of TNF-alpha after hay contact, and a genetic predisposition to TNF-alpha production, are implicated in the pathogenesis of alveolitis in farmer's lung.

TNF receptor-deficient mice reveal divergent roles for p55 and p75 in several models of inflammation.

The pleiotropic activities of the potent proinflammatory cytokine TNF are mediated by two structurally related, but functionally distinct, receptors, p55 and p75, that are coexpressed on most cell types. The majority of biologic responses classically attributed to TNF are mediated by p55. In contrast, p75 has been proposed to function as both a TNF antagonist by neutralizing TNF and as a TNF agonist by facilitating the interaction between TNF and p55 at the cell surface. We have examined the roles of p55 and p75 in mediating and modulating the activity of TNF in vivo by generating and examining mice genetically deficient in these receptors. Selective deficits in several host defense and inflammatory responses are observed in mice lacking p55 or both p55 and p75, but not in mice lacking p75. In these models, the activity of p55 is not impaired by the absence of p75, arguing against a physiologic role for p75 as an essential element of p55-mediated signaling. In contrast, exacerbated pulmonary inflammation and dramatically increased endotoxin induced serum TNF levels in mice lacking p75 suggest a dominant role for p75 in suppressing TNF-mediated inflammatory responses. In summary, these data help clarify the biologic roles of p55 and p75 in mediating and modulating the biologic activity of TNF and provide genetic evidence for an antagonistic role of p75 in vivo.

[Case report of Farmer's lung disease in siblings in Kagoshima Prefecture].

Two cases of farmer's lung disease in siblings are reported. A 54-year-old male farmer, who had been engaged in stock work for 20 years, presented to our clinic for the second episode of fever, productive cough and shortness of breath. Chest roentgenogram revealed diffuse micronodular pattern, and mild hypoxemia was recognized on arterial blood gas analysis. Cytology obtained from BALF showed lymphocytosis, with especially increased OKT3, OKT4 positive cells and OKT4/8 ratio. The diagnosis was confirmed by highly positive reaction of precipitins to Thermoactinomyces vulgaris and granulomatous interstitial pneumonitis on histopathological examination. The second case was a 51-year-old female patient, the sister of the first case, who also worked as a stock farmer of another farm for 20 years. She presented with an episode of similar symptoms to the first case, one and a half years after the onset of her brother's symptoms. The findings of roentgenogram, BALF analysis, precipitins to T. Vulgaris and pathology were similar to those of the first case. The finding of high OKT4/8 ratio on BALF analysis in both cases is characteristic of formers lung disease, in contrast to the summer-type hypersensitivity pneumonitis which usually shows low OKT4/8 ratio in BALF. To our knowledge, this is the first report of farmer's lung disease in an area other than the northern part of Japan. Thus we conclude that farmer's lung disease may occur in Japan under any environmental conditions, and that some genetic factor may take part in the onset of this disease.

Immunologic response to Faenia rectivirgula (Micropolyspora faeni) in a dairy farm family.

In the present study, cellular and humoral responses to Faenia rectivirgula antigens were evaluated in seven subjects, members of a family who lived and worked on a dairy farm. Four subjects had clinical features of hypersensitivity pneumonitis after exposure to moldy hay. The other three subjects had no clinical disease in spite of similar exposure. Although serum precipitins were found in most subjects, a biotin-avidin-linked immunosorbent assay revealed high levels of F. rectivirgula-specific antibodies only in the symptomatic subjects. In addition, numerous precipitin arcs were present in the sera of the symptomatic but not the asymptomatic subjects by antigen-antibody crossed immunoelectrophoresis. No clear distinction between symptomatic and asymptomatic subjects could be made on the basis of lymphocyte phenotype studies, and antigen-induced lymphocyte transformation was not detected in any subjects. The results indicate that F. rectivirgula-specific antibody levels as detected by biotin-avidin-linked immunosorbent assay and by the presence of precipitin arcs in crossed immunoelectrophoresis may differentiate symptomatic and asymptomatic farmers.

[Simultaneous illness in siblings with exogenous allergic alveolitis of the farmer's lung type--report of a 3-year course, familial sensitization and HLA markers]. / Synchrone Geschwistererkrankung an exogen allergischer Alveolitis vom Typ der Farmerlunge--Bericht über 3jährigen Verlauf, familiäre Sensibilisierung und HLA-Merkmale.

Two sisters (6 and 8 years old) fell ill with coughing, fever and dyspnea after playing in the rotten straw in the barn of their parents' farm. Within 2 weeks symptoms changed to the insidious form of Exogen Allergic Alveolitis. In the broad spectrum of antibodies detected, the Thermophile Actinomycetes were probably the relevant antigens. In spite of efforts to avoid contact with the antigens, there was a relapse of the disease, the most probable sources of the antigens being a mattress in the bed-room and a fodderroom. Since consequent avoidance of antigens is practiced, no signs of relapse have been seen. The other three members of the family were exposed too. The mother and the youngest daughter showed neither symptoms nor specific antibodies. The father turned out to be sensibilitized too. By more attentive self-observation he discovered signs of illness. The distribution of the HLA-markers in the family was not concordant with the pattern of disease nor of antibodies. Some HLA-markers have been described as being associated with Exogen Allergic Alveolitis. Among the markers of our family there are none of these.

Familial aggregation of IgG antibody response to antigens associated with farmer's lung.

The levels of circulating IgG antibodies to Aspergillus umbrosus, Aspergillus fumigatus, Thermoactinomyces vulgaris, and Micropolyspora faeni were determined by enzyme immunoassay in 197 subjects selected for a study of farmer's lung (FL). The material consisted of five study groups: 37 patients with clinically confirmed FL, 31 spouses of the patients, 44 immediate relatives of the patients, 35 immediate relatives of the patients' spouses, and 50 unrelated people who were spouses of the 79 people in both relative groups. The mean titres of IgG antibodies to all four microbes were highest in patients with clinically established FL. In the other groups the mean titre of Aspergillus umbrosus, a mould found much more frequently in Finnish farm environments than other moulds under study, was significantly higher (p less than 0.01) in the relatives of FL patients than in other people. This finding remained irrespective of whether the subjects had suffered from FL symptoms or not or whether they worked or lived on the same farm as the patient or on a different one. The difference in the mean titre was not due to the differences between the study groups in age, sex, smoking habits, atopic background, frequency of handling of plant materials, or time interval from the most recent handling of visibly mouldy hay. The results imply that genetic factors may be important in the IgG antibody response to microbial antigens associated with FL.

Familial aggregation of symptoms of farmer's lung.

Not all farmers exposed to moldy plant materials develop farmer's lung. With the use of a postal questionnaire the occurrence of symptoms suggestive of farmer's lung was studied among the immediate relatives of 37 patients with clinically established farmer's lung, among 36 immediate relatives of the patients' spouses, and among 50 unrelated persons (spouses of relatives). Symptoms of farmer's lung had occurred about twice as frequently among the relatives of farmer's lung patients as among the subjects in the other study groups. The results, supported by findings from earlier studies, imply that genetic factors may be involved in the pathogenesis of farmer's lung.

Serologically detectable HLA-A, B, and C loci antigens in farmer's lung disease.

The frequency of serologically detectable (SD) HLA-A, B, and C loci antigens in subjects with farmer's lung disease (N = 100) was compared with that of age- and sex-matched normal normal farmers with no precipitating antibodies to extracts of thermophilic actinomycetes. A subset of the farming population with antibodies to the thermophilic actinomycetes and no evidence of clinical disease (N = 55) was also agae- and sex-matched to the farmer's lung disease population. No significant associations between any of the SD HLA antigens tested and farmer's lung disease were found in the study. The data demonstrated that there was no association between SD HLA antigens and farmer's lung disease in random populations.

Pigeon breeders disease. III. A study of a family exposed to doves.

A family of five individuals exposed to doves in their home were studied to evaluate possible factors leading to sympotmatic hypersensitivity pneumonitis documented in one member of the family, while the other exposed members remained asymptomatic. Antbodies against pigeon serum were domenstrated by radioimmunoassay in all subjects, and significant lymphocyte reactivity against pigeon antigens was demonstrable in three of the five members. The presence of serum antibody activity or lymphocyte reactivity against avian antigens or both did not differentiate the sick from the well family subjects. However, the possibility that increased exposure to antigen may correlate with higher degrees of antibody and lymphocyte reactivity as well as clinical disease is suggested from observation made in this family. No correlation was found between HL-A type and either symptomatic disease or immunological reactivity in these subjects.

Familial hypersensitivity pneumonitis.

Two families are described in which seven members of a total of 19 were found to have hypersensitivity pneumonitis due to exposure to avian antigens. Diagnosis was made on the basis of characteristic roentgenologic changes together with respiratory function and immunologic studies. The latter included screening for precipitins, macrophage migration inhibition (MMI) to specific antigens in avian serum and droppings, quantitation of immunoglobulin and alpha1 antitrypsin (AAT) levels and assessment of the complement system. Specific precipitins to pigeon and/or budgerigar serum were found in the serum of only four of the seven patients. Six of these seven patients, however, had a positive MMI. Thus, the MMI test, at least in this group of patients appeared to be a more sensitive indicator of active disease. The finding of seven members of two families with disease led to a search for predisposing factors, either genetic or environmental. Evidence for a genetic predisposition came from tissue typing studies. In the first family, both paternal haplotypes were associated with disease; the maternal haplotype HLA3,7 was not inherited by any child with disease. In the second family, the disease developed in three of four members with the haplotype HL-A2,W15, who were significantly exposed to avian antigen. In the light of recent studies showing an association between immune response (Ir) genes, histocompatibility antigens and disease susceptibility, these findings were interpreted as possible evidence for a subtle genetically linked immune defect in hypersensitivity pneumonitis. Evidence for an environmental predisposition was less clear cut, but it is interesting that members of both families used a gamma isomer of hexachlorobenzene (Nickoff) to eradicate mite infestations in their birds which might have damaged the bronchial mucosa or acted as an immunologic adjuvant in a person with underlying susceptibility to disease. The presence of subclinical respiratory disease in two family members is reported, and the importance of performing a range of investigations of respiratory function in order to detect disease and monitor its progress is emphasized.