Regulation of macrophage and monocyte immune responses by water extract from the inner bark of Tabebuia avellanedae

Tabebuia sp. (Bignoniaceae) is representative traditional herbal plants, found in tropical rain forest areas throughout Central and South America. These plants have been mostly used as a folk medicine to treat bacterial infection, blood coagulation, cancer and inflammatory diseases. In this study, we aimed to demonstrate the modulatory role of Tabebuia avellanedae in various macrophage-or monocyte-mediated immune responses using its water extract (Ta-WE). Ta-WE was able to up-regulate cell-cell interaction by decreasing the migration of cells and by enhancing CD29-mediated cell-cell adhesion, and the surface levels of adhesion molecules (CD18, CD29, and CD82) and costimulatory molecules (CD80 and CD86) linked to macrophage stimulation as seen in up-regulation of ROS release. In addition, this fraction also suppressed an alteration in the membrane levels of macrophages such as phagocytic uptake and morphological changes. Therefore, these results suggest that the water extract of T. avellanedae can strongly modulate an ability of macrophages and monocytes to manage immune cell-cell interaction in host defence system.