 We will ask you to undergo a challenge with endotoxin, which is a bacterial component of air pollution. From other studies we have done, we know that if you inhale 20,000 EUs endotoxin units we will see an increase in the number of neutrophils a type of white blood cell that your body produces to fight infection in your lung cells without causing you to have flu-like symptoms. We will investigate if there is a change in your lung inflammatory cells after the endotoxin challenge when you take the gT versus when you take a placebo. 