Allergens, inhalant

Wuyts A, Overbergh L, Mathieu C, Ceuppens JL Interleukin-17 orchestrates the granulocyte influx into airways after allergen inhalation in a mouse model of allergic asthma. Am J Respir Cell Mol Biol 2003 28 42-50. 

In short-term clinical trials, pretreatment with cromolyn or nedocromil blocked the bronchoconstriction caused by allergen inhalation, by exercise, by sulfur dioxide, and by a variety of causes of occupational asthma. This acute protective effect of a single treatment makes cromolyn useful for administration shortly before exercise or before unavoidable exposure to an allergen. 

Fahey JV, Fleming HE, Wong HH, Liu J, et al. 1997. The effect of an anti-IgE monoclonal antibody on the early-and late-phase responses to allergen inhalation in asthmatic subjects. Am J Respir Crit Care Med. 155 1828-1834. 

Airflow obstruction in asthma is due to bronchoconstriction resulting from contraction of bronchial smooth muscle, inflammation of the bronchial wall, and increased mucous secretion. Asthmatic attacks may be related to recent exposure to allergens, inhaled irritants leading to bronchial hyperactivity and inflammation of the airway mucosa. The symptoms of asthma may be effectively treated by several drugs, but none of the agents provide a cure for this obstructive lung disease. 

Devalia, J.L., C.Rusznak, M.I.Herdman, C.J.Trigg, H.Tarraf, and R.I.Davies. 1994. Effect of nitrogen dioxide and sulphur dioxide on airway response of mild asthmatic patients to allergen inhalation. Lancet 344(8938) 1668-1671. 

It is a mild allergen. Inhalation may produce bronchial asthma, sneezing, and eczema in sensitized persons. Moderate fire and explosion hazard when exposed to heat or flame can react with oxidizing materials. 

Bentley, A.M., Menq, Q., Robinson, D.S., Hamid, Q, Kay, A.B. and Durham, S.R, (1993). Increases in activated T lymphocytes, eosinophils and cytokine messenger RNA for IL-5 and GM-CSF in bronchial biopsies after allergen inhalation challenge in atopic asthmatics. Am. J. Respir. Cell Mol. Biol. 8, 35-42. 

Pepys, J., Hargreave, F.E., Chan, M. and McCarthy, D.S. (1968). Inhibitory effects of disodium cromoglycate on allergen inhalation tests. Lancet ii, 134-137. 

In an allergen inhalation model of asthma, subjects who develop the EAR have an initial drop in circulating eosinophil count followed by a rise at 48 h post-challenge (Cookson et al. 1989). The initial drop may reflect the recruitment of circulating eosinophils to the lung where they participate in the development of a late phase... 

Challenge of sensitized subjects with inhaled allergen has been a vital experimental approach in asthma research since the first bronchoprovocation studies were performed by Max Samter in Berlin in 1933. Allergen inhalation results in an early bronchoconstrictor ( asthmatic ) response (EAR) at 5 to 10 minutes lasting up to an hour and, in about half of subjects, a late bronchoconstrictor response (LAR) starting at 2 to 3 hours and lasting for 12 to 24 hours (Pepys, 1973). 

ROBINSON, D.S., HAMID, Q BENTLEY, A., YING, S KAY, A.B. DURHAM, S.R. (1993) Activation of CD4+ T cells, increased Th2-type cytokine mRNA expression and eosinophil recruitment in bronchoalveolar lavage after allergen inhalation challenge in patients with atopic asthma. Journal of Allergy and Clinical Immunology, 92, 313-324. 

Allergen inhalation tests are primarily a research tool. For this reason, the principles of standardization have been developed to try and assure the best possible intraindividual reproducibility. The principles of standardization outlined below are based on both scientific and empirical concepts. Standardization encompasses technical aspects (aerosol generation, inhalation, measurement of response) and nontechnical or subject-related aspects, the latter designed to assure patient stability. 

Figure 3 Allergen-induced dual asthmatic response. Legend as per Figure 1. Inhalation of grass pollen extract in this subject resulted in a 28% EAR maximal at 20 minutes with spontaneous resolution at 2 hours, followed by a late asthmatic response with a 45% fall in FEVi 6 hours post-allergen inhalation. (From Ref. 122.)...

Induced-sputum analysis was also able to demonstrate an increase in met-achromatic cells and eosinophils after allergen inhalation (48,76). The late response to allergens was associated with an increased concentration of tumor necrosis factor a (TNFa) and interleukin 5 (IL-5) in induced sputum in addition to an increased eosinophil count and in eosinophil cationic protein (ECP) and eosinophil peroxidase (EPO) (77). After aerosolized allergen challenge, ECP and histamine in induced-sputum supernatant were higher than at baseline (78). Tryp-tase was detectable in the sputum of many subjects. 

Boonsawat W, Salome CM, Woolcock AJ. Effect of allergen inhalation on the maximal response plateau of the dose-response curve to methacholine. Am Rev Respir Dis 1992 146 565-569. 

Crimi E, Violante B, Pellegrino R, Brusasco V. Effect of multiple doses of nedo-cronul sodium given after allergen inhalation in asthma. J Allergy Chn Immunol 1993 92(6) 777-783. 

Zimmermann I, Kowalshi J, Curshmann P, Ulmer WT. Reaction following allergen inhalation via the mouth and via the tracheal tube in dogs. Lung 1976 154 41-49. 

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