Blocking Eotaxin May Prevent Airway Narrowing
Study of guinea pigs and human cell cultures suggests new approach for treating asthma
FRIDAY, Jan. 6 (HealthDay News) -- Blocking eotaxin, a chemokine that attracts eosinophils, may prevent the excessive airway narrowing seen in asthma, according to an article in the Jan. 1 issue of the Journal of Clinical Investigation.
David B. Jacoby, M.D., of Oregon Health and Science University in Portland, and colleagues studied the effects of GW701897B, an antagonist of CCR3 (the sole receptor for eotaxin) on vagal reactivity and M2 muscarinic receptor (M2R) function in ovalbumin-challenged guinea pigs. The investigators were also able, for the first time, to isolate airway nerves from humans and maintain them in cell culture, allowing them to study how these nerves interact with eosinophils.
The researchers found that eotaxin is present in the airway nerves of both guinea pigs and humans, and demonstrated -- in vivo and in vitro -- that eosinophil recruitment to nerves is mediated by the CCR3 receptor. Their tests showed that antigen-challenged guinea pigs that received the CCR3 antagonist were not hyperresponsive to vagal stimulation and did not lose M2R function, unlike antigen-challenged animals that did not receive the antagonist.
"The data presented in this article support CCR3 as a potential drug target in the treatment of asthma," the authors conclude.