Entomologia Experimentalis et Applicata (2007) 124, 285-292

Hyeog Sun Kwon, David W. Stanley and Jon S. Miller (2007)
Bacterial challenge and eicosanoids act in plasmatocyte spreading
Entomologia Experimentalis et Applicata 124 (3), 285-292
Abstract: We report on experiments designed to more thoroughly document the roles of eicosanoids as crucial elements in cell spreading and on experiments designed to test the hypothesis that in vivo bacterial infections influence cell spreading on glass surfaces. We used hemocytes prepared from tobacco hornworms, Manduca sexta (L.) (Lepidoptera: Sphingidae) and four species of bacteria (Serratia marcescens, Escherichia coli, Bacillus subtilis, and Micrococcus luteus) in each experiment. Our protocols yielded several important points: (i) hemocytes prepared from hornworms at 15 and 60 min following infection with, separately, each of the four bacterial species were fundamentally altered in size (all less than the 15-µm counting cut-off) and none of the hemocytes exhibited cell-spreading behavior; (ii) the influence of bacterial challenge on cell spreading declined with incubation time post-challenge; (iii) conditioned medium (CM) prepared by exposing hemocytes to bacterial cells in vitro exerted a strong dose-dependent influence on cell spreading. Specifically, plasmatocytes increased in length from about 38 µm with 2.5% CM to a maximum of about 54 µm at 100% CM; and (iv) the retarding influence of dexamethasone (an eicosanoid biosynthesis inhibitor) on cell spreading was reversed by arachidonic acid, prostaglandin H₂, and CM. Taken together, these findings indicate that both bacterial infection and eicosanoids influence hemocyte-spreading processes.
(The abstract is excluded from the Creative Commons licence and has been copied with permission by the publisher.)
Link to article at publishers website
Database assignments for author(s): David W. Stanley

Research topic(s) for pests/diseases/weeds:
general biology - morphology - evolution

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Pest and/or beneficial records:

Beneficial	Pest/Disease/Weed	Crop/Product	Country	Quarant.
	Manduca sexta