Permeability alteration of microvascular endothelia is a factor in the plasma leakage produced by dengue virus (DV) infection, and beta 3 integrin plays central roles in maintaining capillary integrity and regulating vascular permeability. In this study, interaction between beta 3 integrin and DV serotype 2 (DV2) was investigated using human dermal microvascular endothelial cell line-1 (HMEC-1). We reported that DV2 infection could induce high expression level of beta 3 integrin, and the high fluorescence intensity of beta 3 integrin antigen observed in HMEC-1 after infection showed high co-localization with DV antigen. Pre-incubation of the virus with soluble alpha v beta 3 integrin could strongly inhibit DV2 entry. And about 90% of virus entry was inhibited when beta 3 integrin expression level was down-regulated by RNA interference. Our data indicated that DV2 infection could induce up-regulating expression of beta 3 integrin, and P3 integrin was required for DV2 entry into HMEC-1. (c) 2007 Elsevier Inc. All rights reserved.