Secretory leukocyte protease inhibitor, an inhibitor of neutrophil activation, is elevated in serum in human sepsis and experimental endotoxemia.
OBJECTIVE
To document changes in serum secretory leukocyte protease inhibitor (SLPI) in human sepsis and in experimental endotoxemia in vivo. To compare changes in serum SLPI in human sepsis with changes in interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-alpha. To determine whether or not changes in SLPI correlate with the severity of multiple organ dysfunction syndrome as measured by the maximal multiple organ dysfunction score. Finally, because neutrophils have been implicated in tissue injury associated with organ dysfunction, to determine whether recombinant human SLPI blocks activation of isolated human neutrophils.


METHODS
Case-control study and ex-vivo cellular assay.


METHODS
Surgical intensive care unit and clinical research center of university hospitals; laboratory of a medical school.


METHODS
None.


RESULTS
There was a significant dose-dependent elevation (50.2+/-4.0 ng/mL, p = .01) in plasma SLPI 12 hrs after administration of lipopolysaccharide to seven healthy adults (36.4+/-2.3 ng/mL). Further, serum concentrations of SLPI (132+/-15 ng/mL) were elevated in septic surgical patients compared with healthy controls (43+/-2 ng/mL, p < .01) and nonseptic surgical controls (69+/-10 ng/mL, p = .01). Serum SLPI concentrations correlated (r2 = .71, p < .01) better with organ dysfunction as measured by maximal multiple organ dysfunction score than did serum IL-6 (r2 = .49, p < .01), IL-10 (r2 = .05, p = .22), or TNF-alpha (r2 = .02, p = .44). We found that recombinant human SLPI in vitro inhibits TNF-alpha-induced hydrogen peroxide production by human neutrophils (ID50 = 1-2 microg/mL).


CONCLUSIONS
Serum SLPI is elevated in human sepsis and experimental endotoxemia. Maximal concentrations of serum SLPI correlate significantly with maximal multiple organ dysfunction scores in patients with sepsis. Secretory leukocyte protease inhibitor may function to limit ongoing neutrophil-mediated tissue injury associated with organ dysfunction.
Grobmyer
S R
SR
Department of Surgery, The Joan and Sanford I. Weill Medical College of Cornell University, New York, NY 10021, USA.
Barie
P S
PS
Nathan
C F
CF
Fuortes
M
M
Lin
E
E
Lowry
S F
SF
Wright
C D
CD
Weyant
M J
MJ
Hydo
L
L
Reeves
F
F
Shiloh
M U
MU
Ding
A
A
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D016022:Case-Control Studies; D016207:Cytokines / Q000097:blood; D019446:Endotoxemia / Q000097:blood*; D004926:Escherichia coli / Q000276:immunology; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008070:Lipopolysaccharides / Q000276:immunology; D008297:Male; D008875:Middle Aged; D018375:Neutrophil Activation / Q000276:immunology*; D053491:Proteinase Inhibitory Proteins, Secretory; D011506:Proteins / Q000378:metabolism*; D016897:Respiratory Burst / Q000276:immunology; D053481:Secretory Leukocyte Peptidase Inhibitor; D012772:Shock, Septic / Q000276:immunology*; D018746:Systemic Inflammatory Response Syndrome / Q000276:immunology*
D016207:Cytokines; D008070:Lipopolysaccharides; D053491:Proteinase Inhibitory Proteins, Secretory; D011506:Proteins; C506814:SLPI protein, human; D053481:Secretory Leukocyte Peptidase Inhibitor