Abstract
Asthma with complete airflow reversibility (ACR) represents the majority of asthma cases, however recent attention has focussed increasingly on a small subset of asthmatics that display incomplete airflow reversibility despite optimal treatment (AIR), also a feature of COPD. A growing amount of literature has linked the three main types of killer cells, namely CD8 T cells, Natural Killer (NK) and NKT cells, to both ACR and COPD due to their cytotoxic and immunoregulatory functions. We aimed to study the role of these cells in AIR. Absolute cell counting, cytotoxic mediator and receptor profiling, activation time course assays as well as functional cytotoxic experiments were performed to compare the number and function of killer cell subsets in the peripheral blood of AIR and ACR patients and healthy controls. Our data suggest both the number and cytotoxic function of these killer cells are reduced in the peripheral blood of AIR patients compared to ACR patients, as quantified by perforin/granzyme B expression and functional cytotoxic assays. This indicates killer cells may be recruited to the AIR lung and have a subsequent role in the disease pathogenesis, as has been shown in COPD.
- © 2011 ERS