Time-dependent expression of annexin 1 in a model of chronic granulomatous inflammation.
OBJECTIVE
To determine the expression pattern and distribution of the glucocorticoid-inducible protein annexin 1 (ANXA1) in a murine model of chronic granulomatous inflammation.


METHODS
TO Mouse.


METHODS
Chronic granulomatous inflammation was induced by injecting into dorsal sub-cutaneous air-pouches in mice, a mixture of croton oil and Freund's complete adjuvant (CO/FCA).


METHODS
Western and northern analysis, corticosterone assay, and immunohistochemistry. Statistical analysis was performed using ANOVA followed by Tukey's pair-wise comparisons or Dunnett's multiple comparisons.


RESULTS
ANXA1 protein levels changed significantly throughout the 4-week time course, with an initial peak at day 7 and a later elevation at 28 days. ANXA1 mRNA levels peaked at days 1 and 3, with a significant decline at day 7 followed by an upward trend to day 28. Plasma corticosterone measurements taken throughout the time course revealed an increase from 14 days onward, suggesting that corticosterone does not influence ANXA1 expression during the initial stages of the model. Immunogold staining revealed that ANXA1 expression in the inflamed tissue was mainly in extravasated neutrophils, with intact protein (37 kDa) being predominantly observed on the cell membrane.


CONCLUSIONS
The pattern of ANXA1 expression indicates that infiltrated neutrophils are responsible for the majority of ANXA1 present both at early and later stages of this model of granulomatous inflammation.
Gibbs
L
L
Department of Biochemical Pharmacology, The William Harvey Research Institute, London, UK. lindagibbs@bigfoot.com
Carollo
M G
MG
Damazo
A S
AS
Oliani
S M
SM
Perretti
M
M
D000818:Animals; D017305:Annexin A1 / Q000032:analysis* / Q000235:genetics; D002908:Chronic Disease; D003345:Corticosterone / Q000097:blood; D005260:Female; D006099:Granuloma / Q000378:metabolism*; D007150:Immunohistochemistry; D007249:Inflammation / Q000378:metabolism*; D051379:Mice; D009504:Neutrophils / Q000502:physiology; D012333:RNA, Messenger / Q000032:analysis; D013997:Time Factors
D017305:Annexin A1; D012333:RNA, Messenger; D003345:Corticosterone