Naslov
Altered Plasma Granzyme K Levels in Patients with Early Symptoms of Sepsis and Severe Sepsis

Autori
M. Ručević, L.D. Fast, G. Jay, S.M. Opal and Y.P. Lim.

Vrsta, podvrsta i kategorija rada
Sažeci sa skupova, sažetak, znanstveni

Skup
3rd Annual COBRE CCRD Research Symposium

Mjesto i datum
Providence (RI), Sjedinjene Američke Države, 24.06.2005

Vrsta sudjelovanja
Poster

Vrsta recenzije
Nije recenziran

Ključne riječi
Granzym K levels; Early Sepsis; Severe Sepsis

Sažetak
Granzymes (Grs) belong to the family of granule associated serine proteases that are expressed by cytotoxic T lymphocytes (CTL) and Natural killer (NK) cells and play important role in target cell apoptosis. Recently, a number of additional functions have been postulated for Grs. They can cleave a number of extracellular matrix proteins, and thus may facilitate migration of CTL and NK cells through extracellular tissues. Grs can also induce cytokine secretion and directly activate various cytokines suggesting their involvement in inflammation responses. Although the pro-inflammatory properties of Grs have been described, the exact physiological substrate of granzymes remains uncertain. Our previous studies have demonstrated that a significant decrease of plasma level of natural serine proteases inhibitors (inter-alpha inhibitor proteins, IaIp) is found in septic patients. Recently, IaIp have been identified as the physiological inhibitor of granzyme K (GrK). This has prompted us to hypothesize that GrK, as a protease, may also play a role in pathogenesis of sepis. We have successfully generated and characterized rabbit anti-GrK polyclonal antibodies against a peptide sequence unique for GrK and developed an immunoassay for detection of GrK levels in plasma. The developed assay was highly sensitive and reproducible with a detection range of 15-1000 U/mL. GrK levels were evaluated in healthy controls and in patients with sepsis. Plasma from two patient groups were collected: patients enrolled in the septic clinical trial (CT) and septic patients admitted in the Emergency Department (ED). The latter group represents patients with the early stage of sepsis when the diagnosis was established at the time of admission. While we confirmed that IaIp level in all septic patients were significantly lower than in healthy controls, GrK levels were found significantly higher in ED patients (mean &plusmn ; SD = 1378 &plusmn ; 189 U/mL, n=15) and significantly lower in CT patients (157 &plusmn ; 19 U/mL, n=10) compared to healthy controls (747 &plusmn ; 75 U/mL, n=15). The differences between the septic groups (p<0.0001) and ED to healthy controls (p<0.0015) or CT to healthy controls (p<0.0001) were significant. Western blot analysis confirmed the detection of GrK and revealed a reactive band in human plasma corresponding to ca. 28 kDa. Taken together, the results suggest that GrK level in plasma might be useful as an early marker in patients developing sepsis.

Izvorni jezik
Engleski

Znanstvena područja
Kliničke medicinske znanosti, Biotehnologija

POVEZANOST RADA