Abstract
INTRODUCTION: Bronchial thermoplasty (BT) is an effective treatment for carefully selected uncontrolled asthma patients. The treatment has significant effect on the structural cells of the airway wall and offers long-term beneficial clinical effects with minor side effects. Reports of other possible mechanisms of BT action are only scant.
AIMS: We focused on inflammatory response after BT with the aim to detect the possible changes in T cell populations in severe asthmatic airways after treatment with BT.
METHODS: We included 4 patients with uncontrolled asthma who were treated with BT at our clinic from Nov 2013 till March 2014. Bronchoalveolar lavage (BAL) samples were collected from the right lower lobe prior to, 3 and 6 weeks post initial BT. Samples were analysed by flow cytometry to determine the subsets of BAL T cells and their expression of activation and differentiation markers; CD4, CD8, CCR4, CXCR3, CCR6, CD25, CD69, HLA DR, CD27, CD28.
RESULTS: At baseline, more BAL T cells expressed CD3+8+ cytotoxic (Tc) than helper T cell markers. Most of T cells expressed early activation marker CD69 and majority of Tc expressed fully differentiated phenotype CD27-CD28-. Th17 cells presented 14%, and CD4+25+ regulatory T cells (Treg) 25% of studied lymphocyte population. At 3 and 6 weeks after treatment we detected increase in Treg population to more than 40%. Treated patients reported less severe exacerbations and less symptoms in a year following BT treatment.
CONCLUSIONS: The substantial increase of BAL immunomodulatory regulatory T cell proportion after BT treatment indicates the possible influence of BT not only on structural changes but also on inflammatory response.
- Copyright ©the authors 2016