Importantly, we provide ex vivo evidence for the refractoriness of M(IL-4/IL-13) macrophages to become foamy by finding a negative correlation between the expression of CD209, a bona fide marker in human M(IL-4)-associated, and the numbers of LBs-containing CD14+ cells isolated directly from the pleural cavity of TB patients, thus providing physiological relevance to our in vitro findings. The gene discussed is CD14; the disease is tuberculosis.