Immune targeting of the pleural space by intercostal approach

Georg F Weber

Infectious diseases of the airways are a major health care problem world wide. New treatment strategies focus on employing the body's immune system to enhance its protective capacities during airway disease. One source for immune-competent cells is the pleural space, however, its immune-physiological function remains poorly understood. The aim of this study was to develop an experimental technique in rodents that allows for an in vivo analysis of pleural space immune cells participating in the host defense during airway disease. I developed an easy and reliable technique that I named the "InterCostal Approach of the Pleural Space" (ICAPS) model that allows for in vivo analysis of pleural space immune cells in rodents. By injection of immune cell altering fluids into or flushing of the pleural space the immune response to airway infections can be manipulated. The results reveal that (i) the pleural space cellular environment can be altered partially or completely as well as temporarily or permanently, (ii) depletion of pleural space cells leads to increased airway inflammation during pulmonary infection, (iii) the pleural space contributes immune competent B cells during airway inflammation and (iv) inhibition of B cell function results in reduced bacterial clearance during pneumonia. As the importance for in-depth knowledge of participating immune cells during health and disease evolves, the presented technique opens new possibilities to experimentally elucidate immune cell function, trafficking and contribution of pleural space cells during airway diseases.