The effect of two bisphosphonates on human neutrophil chemiluminescence and myeloperoxidase activity

In order to assess the importance of chlorine in a drug molecule as an influence on myeloperoxidase-mediated inflammatory cell functions, the effect of the chlorinated bisphosphonate, clodronate, on human neutrophil chemiluminescence and myeloperoxidase (MPO) activity was compared to the non-chlorinated structural analogue, etidronate. The results suggested that the presence of chlorine may be important to the enhancement of MPO activity. In addition both drugs manifested low toxicity and both of these observations may have relevance to host defence.