Invariant Natural Killer T Cells in Asthma and Chronic Obstructive Pulmonary Disease

Abstract

The number of type 2 helper CD4+ T cells is increased in the airways of persons with asthma. Whether the majority of these cells are class II major-histocompatibility-complex–restricted cells or are among the recently identified CD1d-restricted invariant natural killer T cells is a matter of controversy. We studied the frequency of invariant natural killer T cells in the airways of subjects with mild or moderately severe asthma to investigate the possibility of an association between the number of invariant natural killer T cells in the airway and disease severity. We also studied whether an increased number of these cells is a feature of chronic obstructive pulmonary disease (COPD).