Abstract:
:This article demonstrates that a simple chemical model system, built by using a modular approach, may be used to predict the spatiotemporal dynamics of initiation of blood clotting in the complex network of hemostasis. Microfluidics was used to create in vitro environments that expose both the complex network and the model system to surfaces patterned with patches presenting clotting stimuli. Both systems displayed a threshold response, with clotting initiating only on isolated patches larger than a threshold size. The magnitude of the threshold patch size for both systems was described by the Damköhler number, measuring competition of reaction and diffusion. Reaction produces activators at the patch, and diffusion removes activators from the patch. The chemical model made additional predictions that were validated experimentally with human blood plasma. These experiments show that blood can be exposed to significant amounts of clot-inducing stimuli, such as tissue factor, without initiating clotting. Overall, these results demonstrate that such chemical model systems, implemented with microfluidics, may be used to predict spatiotemporal dynamics of complex biochemical networks.
journal_name
Proc Natl Acad Sci U S Aauthors
Kastrup CJ,Runyon MK,Shen F,Ismagilov RFdoi
10.1073/pnas.0605560103subject
Has Abstractpub_date
2006-10-24 00:00:00pages
15747-52issue
43eissn
0027-8424issn
1091-6490pii
0605560103journal_volume
103pub_type
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