Eosinophil major basic protein enhances the expression of neutrophil CR3 and p150,95.
BACKGROUND
We examined the effect of major basic protein (MBP) stimulation on the expression of the neutrophil B2-integrins: LFA-1 (CD11a/CD18), CR3 (CD11b/CD18), and p150,95 (CD11c/CD18).


METHODS
Incubation of neutrophils with 0.75 to 3.0 mumol/L MBP for 30 minutes at 37 degrees C resulted in concentration-dependent increases in CR3 expression as detected by staining with the CD11b-specific monoclonal antibody, Leu-15.


RESULTS
The expression of CR3 was significantly (p < 0.001) higher when neutrophils were stimulated with 1.5 mumol/L (53% +/- 9% increase) or 3.0 mumol/L (100% +/- 17% increase) MBP as compared with unstimulated neutrophils. The kinetics of MBP-stimulated CR3 expression were rapid and were similar to those of 100 nmol/L. N-formyl-methionyl-leucyl-phenylalanine-stimulated enhancement of CR3 expression. Incubation of neutrophils with reduced and alkylated MBP resulted in significantly lower (p < 0.05) increases in CR3 expression as compared with stimulation with native MBP. In addition, neither eosinophil cationic protein nor eosinophil-derived neurotoxin altered neutrophil CR3 expression. MBP stimulated minimal increases in LFA-1 expression. However, staining with the monoclonal antibody Leu-M5 (anti-CD11c) revealed that MBP stimulated significant increases in the expression of p150,95.


CONCLUSIONS
These results indicate that MBP stimulates the increased expression of neutrophil adhesion molecules, which in turn may enhance the inflammatory role of neutrophils in the late-phase events of allergic diseases.
Moy
J N
JN
Department of Immunology/Microbiology, Rush Medical College, Chicago, IL 60612-3864.
Thomas
L L
LL
Whisler
L C
LC
D001798:Blood Proteins / Q000276:immunology*; D002448:Cell Adhesion; D047091:Eosinophil Granule Proteins; D005434:Flow Cytometry; D006801:Humans; D016167:Integrin alphaXbeta2 / Q000096:biosynthesis*; D016169:Lymphocyte Function-Associated Antigen-1 / Q000096:biosynthesis*; D016177:Macrophage-1 Antigen / Q000096:biosynthesis*; D009240:N-Formylmethionine Leucyl-Phenylalanine / Q000494:pharmacology; D009504:Neutrophils / Q000276:immunology*; D012260:Ribonucleases
D001798:Blood Proteins; D047091:Eosinophil Granule Proteins; D016167:Integrin alphaXbeta2; D016169:Lymphocyte Function-Associated Antigen-1; D016177:Macrophage-1 Antigen; D009240:N-Formylmethionine Leucyl-Phenylalanine; D012260:Ribonucleases