Objective: Actin is the dominating intracellular protein and is released to
the circulation after tissue injury. Gc-globulin is one of the plasma prot
eins responsible for removal of actin from the circulation. Recent studies
have shown that the level of Gc-globulin is reduced shortly after trauma. S
erial changes in Gc-globulin after severe injury have not been studied so f
ar and could provide additional information about the role of Gc-globulin i
n the pathophysiological response to trauma.
Design: Prospective, observational.
Setting: Surgical intensive care unit in a university hospital.
Patients: Thirty-eight patients were included in the study: 12 women and 26
men with a median age of 38 years (range 19-86) and a median Injury Severi
ty Score (ISS) of 18 (range 6-45). Seven patients died, on day 5, 8, 8, 10,
10, 13 and 21, respectively.
Interventions: None.
Measurements and main results: The serum concentration of Gc-globulin (Gc(t
otal)) and the percentage of Gc-globulin bound to actin (Gc(%complexed)) we
re measured daily for 1 week using rocket immunoelectrophoresis. Concentrat
ions of free Gc-globulin (Gc(free)) and Gc-globulin bound to actin (Gc(boun
d)) were calculated from these analytical results. The concentration of Gc(
total) and Gc(complexed) correlated significantly (r = -0.99, p < 0.001) th
roughout the time period. After day 3 levels of Gc(complexed) normalised, w
hereas levels of Gc(total) continued to increase above control values. The
concentrations of Gc(total) and Gc(free) were significantly lower in non-su
rvivors compared to survivors; p = 0.005 andp = 0.03, respectively. This wa
s combined with an inverse correlation of Gc(bound) between these two group
s (r = -0.73; p= 0.04).
Conclusions: Severe injury results in a prolonged load on the extracellular
actin scavenger system; more pronounced in patients who do not survive. Gc
-globulin displays characteristics of an acute phase reactant, with supra-n
ormal serum levels 1 week after severe injury, Serial measurements of Gc-gl
obulin after trauma could prove to be a method of early identification of p
atients with increased risk of mortality.