In vitro effects of the nonsteroidal anti-inflammatory drug, ibuprofen, on the immune parameters of the colonial ascidian Botryllus schlosseri.

In this study, in vitro effects of ibuprofen (IBU) on the immune parameters of the colonial ascidian Botryllus schlosseri were evaluated. Haemocytes were exposed for 1 h to 0 (control), 100 and 1000 µg IBU/L and the effects on haemocyte viability and morphology (shape factor), lysosomal membrane stability (Neutral Red retention assay), phagocytic activity, apoptosis (TUNEL reaction), hydrolytic (acid phosphatase) and oxidative (phenoloxidase and peroxidase) enzyme activities were evaluated. The exposure of haemocytes to IBU did not affect significantly their viability, but increased the percentage of cells with round shape. IBU caused a significant reduction in both phagocytic activity and lysosomal membrane stability. The percentage of haemocytes positive to TUNEL reaction (indicative of DNA fragmentation) increased significantly after IBU exposure. Significant decreases in the percentage of haemocytes positive to acid phosphatase were recorded at 1000 µg/L of IBU. Conversely, no significant variations were recorded in the percentage of haemocytes positive to phenoloxidase and peroxidase. Results obtained indicate that exposure of ascidian haemocytes to IBU induces marked alterations in cell functionality. Immunomarkers measured in this study are sensitive, rapid and reproducible. However, their responsiveness and biological relevance will need to be verified for in vivo exposure.