Allergy.  1994 Dec;14(4):658-673.

Comparative study on the activation status of neutrophils in exercise -and allergen- induced asthma

• Choi JH
• Kim H
• Kim HJ
• Koh YY
• Yoon KA

Abstract

Asthma is considered today to be an inflammatory disease. The chronic asthmatic disease characterized by a bronchial hyperreactivity is assumed to be the result of an ongoing inflam matory process. The mechanism responsible for the inflammatory events are not entirely under stood, but recent investigations point to a crucial role for the granulocytes such as neutrophils or eosinophils. Some studies suggest that circulating neutrophils from asthmatic subjects are activated after challenge with allergen. Exercise is one of the most ubiquitous triggets of acute bouts of asthma. LARs have been described following strenuous exercise in several studies, although the prevalence is low. However, most authors reported that airway respon siveness is not increased after exercise, even in the subjects with LAR to exercise. We have frequently seen asthmatic children whose complaint is that symptoms are exacerbated at night after strenuous daytime exercise. There fore, it is crucial to know whether exercise can induce airway inflammation, as in allergen-induced asthma. However, it is very difficult to pursue this, especially in children, because bronchoalveolar lavage or endotracheal biopsy is not feasible both technically and ethically. Therefore, as an indirect measure to investigate whether exercise can induce airway inflammation, as in allergen-induced asthma, we measured the activation status of neutrophil granu locyte in the early and late phase of allergen- or exercise- induced asthma. Eight subjects who showed EAR and LAR (group 1), or EAR only (group 2) to allergen(Dermatophagoides pteronyssinus) challenge were selected. Similarly eight subjects who showed EAR and LAR (group 3), or EAR only (group 4) to exercise challenge were selected. Neutrophil granulocytes were separated from the venous blood at baseline, the early phase, the late phase, and 24 hours after each stimuli. Complement receptors(CR1 and CR3) were enumerated with monoclonal antibodies against the receptors and flow cytometry. Then migratory responses of neutrophils to LTB4(10- 6M/L) were measured, and superoxide anjou generations stimulated by PMA(10-7M/L) were also measured. In the dual responders(Group 1 and 3), there was a significantly increased expression of CR1 and CR3, at EAR and LAR after allergen or exercise challenge. In the single responders (Group 2 and 4), CR1 expression was increased at EAR and late phase after allergen or exercise challenge, but CR3 expression was increased only at EAR. Neutrophil chemotaxis to LTB4 did not show a significant change in the time course after allergen or exercise challenge in any group. Superoxide anion generation stimulated by PMA did not show any change, either. These results indicate that not only allergen but also exercise can activate neutrophils in accordance with the airway response to the stimuli. The present findings suggest that exercise can also have the potential to induce airway inflammation. Therefore exercise should be understood not only as a triggering factor of broncho-constriction but also as one that incites or deteriorates airway inflammation.

MeSH Terms

Antibodies, Monoclonal
Asthma*
Biopsy
Bronchial Hyperreactivity
Bronchoalveolar Lavage
Chemotaxis
Child
Complement System Proteins
Ear
Eosinophils
Family Characteristics
Flow Cytometry
Granulocytes
Humans
Inflammation
Leukotriene B4
Neutrophils*
Prevalence
Superoxides
Antibodies, Monoclonal
Complement System Proteins
Leukotriene B4
Superoxides