Latent antithrombin levels in children and adults

摘要

Antithrombin (AT), a key anticoagulation protein, has been shown to exist in various isoforms; native AT (NAT), cleaved AT, pre-latent AT (pre-LAT) and latent AT (LAT). Approximately 3% of the total AT circulating in adults exists in the latent conformation [1]. The conversion of NAT to LAT has been shown to be caused by an irreversible conforma-tional change. This conversion is an essential function of AT which allows senescence to be maintained in the healthy individual [2]. LAT has been associated with the onset of severe and sudden thrombosis in seriously ill patients [2-6]. In addition, LAT has potent anti-angiogenic activity that is comparable to that of other naturally produced angiogenesis inhibitors such as endostatin [4,7,8]. The anti-angiogenic properties of LAT are particularly important in the setting of AT supplementation, especially in seriously ill paediatric patients that regularly receive this product [9].