The Ennis Group

My interests span the role of infection, inflammation and inflammatory markers in asthma, bronchiectasis, chronic obstructive pulmonary disease and cystic fibrosis. In particular, I am interested in the change of cellular function with disease. My work is wholly with human samples, so all projects are collaborative.

I have a long-standing interest (>25 years) in mast cell heterogeneity and have developed methods for the isolation of mast cells from different tissues and species. In particular, our interests have concentrated on mast cells from the lung both enzymatically dispersed from lung tissue and obtained through bronchoalveolar lavage. These cells are used for the study of mediator release and its inhibition, with particular reference to neuropeptides, antiallergic compounds and the modification of responses by underlying disease states.  I have also worked on basophil activation using flow cytometric assays as well as measuring histamine release.

More recently, I have become interested in neutrophil function and apoptosis. We are investigating peripheral blood neutrophil function in diseases such as COPD and cystic fibrosis, as well as apoptosis in sputum neutrophils. Together with Dr Karim Dib, I am investigating the role of the histamine H4 receptor in human neutrophils. We are working together with industry (Rob Thurmond, Janssen) and academia (Professors Stark (Frankfurt) and Buschauer (Regensburg) to assess different agonists and antagonists. Currently this work is only on blood neutrophils from healthy subjects but we would like to extend it to samples from patients with disease especially severe asthma, COPD and cystic fibrosis. I also have preliminary data on cultured airway epithelial cell lines that indicates a difference in response to H4 receptor activation between control and CF cell lines. I would like to extend this work to primary cells and other airway diseases.

Using primary epithelial cell cultures, developed within the group, we are also examining the properties of nasal and bronchial epithelial cell cultures from subjects with COPD, smokers and non-smokers. Our recent data have shown that the nasal cells are in many ways similar to those from the bronchial tract but that there are differences especially with respect to the response to cigarette smoke extract. Thus for these studies cells must be harvested from the bronchial epithelium. Also, within the COPD research (together with Stuart Elborn and Michael Tunney), we are investigating the airway microbiome in patients with COPD.  This project investigates the presence of aerobic and anaerobic bacteria, viruses and fungi in sputum obtained from patients with COPD at the beginning and end of an exacerbation and when healthy. This will be compared to inflammatory cells and mediators in the sputum.

Our cystic fibrosis research (together with Stuart Elborn and Bettina Schock) examines the interaction of bacteria and other agents with epithelial cells, both cells lines and primary nasal cells. There are 2 main areas of research, firstly the role of anaerobic bacteria in airway inflammation. The second, investigates pathways involved in epithelial cell activation and inhibition of activation (see Bettina Schock for further details)