CD66b overexpression and homotypic aggregation of human peripheral blood neutrophils after activation by a gram-positive stimulus.
Neutrophils represent the main component of innate immunity in the clearance of bacterial infections. To pass the tissue and to localize and reach the site of infection, the peripheral blood neutrophils have to pass through a complex receptor-mediated interaction with the endothelial layer. Under pathophysiological conditions, such as severe sepsis, this process is impaired and often characterized by neutrophil aggregation. In this study, we examined the impact of three different Staphylococcus aureus strains on the activation status of human peripheral blood neutrophils by coincubation of bacterial culture supernatant with whole blood. This complex interaction of a gram-positive stimulus with blood components leads to a special neutrophil activation phenotype, which is characterized by an overexpression of the cell-surface molecule CD66b. The process is accompanied by a strong increase of homotypic aggregates and seems to be initialized by a massive activation impulse caused by the interplay of plasma components. This maximum activation of neutrophils prior to the complex and highly regulated activation required for transmigration might play a key role in the neutrophil dysfunction in gram-positive sepsis.
Federal Institute for Drugs and Medical Devices, L2-Biosafety Laboratory, Bonn, Germany.
Thomas
T
Schmidt
Josef
J
Zündorf
Thomas
T
Grüger
Kerstin
K
Brandenburg
Ana-Lena
AL
Reiners
Jörg
J
Zinserling
Norbert
N
Schnitzler
D000328:Adult; D000818:Animals; D015703:Antigens, CD / Q000378:metabolism*; D015153:Blotting, Western; D002448:Cell Adhesion / Q000502:physiology*; D015815:Cell Adhesion Molecules / Q000378:metabolism*; D002478:Cells, Cultured; D004797:Enzyme-Linked Immunosorbent Assay; D005434:Flow Cytometry; D058851:GPI-Linked Proteins / Q000378:metabolism; D006801:Humans; D008875:Middle Aged; D018375:Neutrophil Activation; D009504:Neutrophils / Q000276:immunology* / Q000378:metabolism* / Q000382:microbiology; D013203:Staphylococcal Infections / Q000276:immunology* / Q000378:metabolism / Q000382:microbiology; D013211:Staphylococcus aureus / Q000276:immunology* / Q000302:isolation & purification; D013552:Swine; D055815:Young Adult
D015703:Antigens, CD; C504120:CEACAM8 protein, human; D015815:Cell Adhesion Molecules; D058851:GPI-Linked Proteins