The second way microbubble CEU may be effective at identifying active inflammation is an indirect effect of new microvasculature. Neoangiogenesis is thought to contribute to pathogenesis by fostering the recruitment and activation of an increased number of leukocyte into the inflamed mucosa. It has been observed that both albumin and lipid shell MB used for echocardiographic studies are phagocytosed intact by activated leukocytes, some of which are adherent to the inflamed endothelium of small intestine or colon. These phagocytosed MB retain a percentage of their acoustic properties, enabling US to image inflammation non-invasively in an in vivo setting. Incorporation of specific lipid moieties into the microbubble shell increases retention and phagocytosis by activated leukocytes.