In:
Blood, American Society of Hematology, Vol. 92, No. 11 ( 1998-12-01), p. 4446-4452
Abstract:
P-selectin is an adhesion receptor for leukocytes expressed by activated platelets and endothelial cells. To assess a possible role of P-selectin in platelet clearance, we adapted an in vivo biotinylation technique in mice. Wild-type and P-selectin–deficient mice were infused with N-hydroxysuccinimido biotin. The survival of biotinylated platelets was followed by flow cytometry after labeling with fluorescent streptavidin. Both wild-type and P-selectin–deficient platelets presented identical life spans of about 4.7 days, suggesting that P-selectin does not play a role in platelet turnover. When biotinylated platelets were isolated, activated with thrombin, and reinjected into mice, the rate of platelet clearance was unchanged. In contrast, storage of platelets at 4°C caused a significant reduction in their life span in vivo but again no significant differences were observed between the two genotypes. The infused thrombin-activated platelets rapidly lost their surface P-selectin in circulation, and this loss was accompanied by the simultaneous appearance of a 100-kD P-selectin fragment in the plasma. This observation suggests that the platelet membrane P-selectin was shed by cleavage. In conclusion, this study shows that P-selectin, despite its binding to leukocytes, does not mediate platelet clearance. However, the generation of a soluble form of P-selectin on platelet activation may have biological implications in modulating leukocyte recruitment or thrombus growth.
Type of Medium:
Online Resource
ISSN:
1528-0020
,
0006-4971
DOI:
10.1182/blood.V92.11.4446
Language:
English
Publisher:
American Society of Hematology
Publication Date:
1998
detail.hit.zdb_id:
1468538-3
detail.hit.zdb_id:
80069-7
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