Detection of a similar to 100 kD protein with strong immunoreactivity to antibodies specific for inducible nitric oxide synthase (iNOS) but without NOS activity in neutrophils of patients suffering from sepsis: Results of a preliminary study
N. Richter et al., Detection of a similar to 100 kD protein with strong immunoreactivity to antibodies specific for inducible nitric oxide synthase (iNOS) but without NOS activity in neutrophils of patients suffering from sepsis: Results of a preliminary study, INFLAMM RES, 48(12), 1999, pp. 651-656
Objective: The study was designed to evaluate the expression of inducible n
itric oxide synthase (iNOS) in activated human neutrophils.
Subjects and Methods: By Western blotting and immunocytochemical staining,
iNOS expression was analyzed in neutrophils from patients with sepsis who w
e classified by high plasma nitrate as subjects with activated NO metabolis
m. For comparison, rats treated with Zymosan documented to induce iNOS were
analyzed.
Results: Strong immunoreactivity to antibodies for iNOS was detected in leu
kocytes of Zymosan treated rats and in neutrophils of septic patients. Such
immunoreactivity was absent in untreated rats and healthy subjects. In rat
s, the immunoreactivity was associated to the 130 kD protein as expected fo
r iNOS. In contrast, the intense iNOS staining in neutrophils of septic pat
ients was associated to a similar to 100 kD protein. Despite the iNOS stain
ing, no increased NOS activity could be demonstrated in the neutrophils of
septic patients.
Conclusions: The detection of a similar to 100 kD protein with immunoreacti
vity to antibodies recognizing human iNOS but without NOS activity in neutr
ophils of patients with sepsis should initiate studies to elucidate the ori
gin and function of this protein.