Mini-plasminogen like molecule in septic patients.

Plasma from 7 septic patients with positive blood cultures were studied. None of them presented either clinical or laboratory evidence of Disseminated Intravascular Coagulation. The white cells count varied between 5 and 45 X 10(9)/l. In plasma functional plasminogen levels varied between 25 and 45%, while those of alpha 2-antiplasmin were normal (80-105%). The levels of elastase ranged between 250 and 750 micrograms/ml. Leukocyte elastase digests plasminogen "in vitro" and is able to produce several fragments; one of them called mini-plasminogen lacking lysine binding sites; therefore it does not bind to lysine-Sepharose 4B. Two different behaviors were observed in the plasmatic plasminogen of these patients with respect to their binding capacity to lysine-Sepharose 4 B. 3 patients had plasminogen which did not bind to lysine-Sepharose 4 B; the other 4 had two different components, one of which bound to lysine-Sepharose 4 B and another one which did not bind. Previous studies "in vitro" have shown that leukocyte elastase modifies alpha 2-antiplasmin, initially producing a non-plasminogen binding form. A free alpha 2-antiplasmin (non-plasminogen binding form) was detected in the plasma of these patients with sepsis by crossed immunoelectrophoresis with plasminogen in the first dimension. It seems tenable that high levels of leukocyte elastase could be responsible for these findings although, the possible relationships to leukocyte elastase still remain to be proven but could possibly explain this effect.