Paradoxical cytoskeleton and microparticle formation changes in monocytes and polymorphonuclear leukocytes in severe systemic inflammatory response syndrome patients.
BACKGROUND
Circulating monocytes and polymorphonuclear leukocytes (PMNLs) are considered as central regulators controlling systemic inflammatory response after severe insults. Recently, activated monocytes and PMNLs have been reported to produce microparticles (MPs) in vitro. The objective of this study was to evaluate production of MPs and changes of cytoskeleton in monocytes from severe systemic inflammatory response syndrome (SIRS) patients, and to compare them with those in PMNLs.


METHODS
Twenty severe SIRS patients (SIRS criteria and serum C-reactive protein > 10 mg/dL) and 15 healthy volunteers were included. MP formation and F-actin content in monocytes and PMNLs were measured by flow cytometry in the presence or absence of lipopolysaccharide or formylmethionyl-leucyl-phenylalanine (FMLP). The membrane expression of human leukocyte antigen-DR and CD64 in monocytes and O2- production in PMNLs were also measured by flow cytometry.


RESULTS
In severe SIRS patients, MP formation with and without lipopolysaccharide in monocytes significantly decreased in comparison with those in normal controls (p < 0.05), whereas those with and without FMLP in PMNLs increased (p < 0.05). F-actin content with and without FMLP in monocytes also significantly decreased in patients (p < 0.05), whereas those in PMNLs increased as compared with normal controls (p < 0.05). The expression of human leukocyte antigen-DR in monocytes significantly decreased in patients (p < 0.05), which indicated monocyte modulation. The O2- production in PMNLs increased in patients (p < 0.05), which showed PMNL activation.


CONCLUSIONS
The changes of MP formation and cytoskeleton in circulating monocytes and PMNLs were paradoxically different in severe SIRS patients.
Itakura Sumi
Yuka
Y
Department of Traumatology, Suita-shi, Osaka University Medical School, Japan. itakura@hp-emerg.med.osaka-u.ac.jp
Ogura
Hiroshi
H
Tanaka
Hiroshi
H
Koh
Taichin
T
Fujita
Kieko
K
Fujimi
Satoshi
S
Nakamori
Yasushi
Y
Shimazu
Takeshi
T
Sugimoto
Hisashi
H
D008841:Actin Cytoskeleton / Q000378:metabolism / Q000473:pathology; D000199:Actins / Q000032:analysis* / Q000378:metabolism / Q000648:ultrastructure; D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002097:C-Reactive Protein / Q000378:metabolism; D016022:Case-Control Studies; D003599:Cytoskeleton / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005434:Flow Cytometry; D006684:HLA-DR Antigens / Q000032:analysis / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D007958:Leukocyte Count; D008070:Lipopolysaccharides / Q000008:administration & dosage; D008297:Male; D008875:Middle Aged; D009000:Monocytes / Q000737:chemistry / Q000378:metabolism / Q000473:pathology*; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000008:administration & dosage; D009504:Neutrophils / Q000737:chemistry / Q000378:metabolism / Q000473:pathology*; D010084:Oxidation-Reduction; D017452:Receptors, IgG / Q000032:analysis / Q000378:metabolism; D012720:Severity of Illness Index; D018746:Systemic Inflammatory Response Syndrome / Q000097:blood* / Q000209:etiology / Q000276:immunology / Q000378:metabolism
D000199:Actins; D006684:HLA-DR Antigens; D008070:Lipopolysaccharides; D017452:Receptors, IgG; D009240:N-Formylmethionine Leucyl-Phenylalanine; D002097:C-Reactive Protein