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Anaphylatoxin-like molecules generated during complement activation induce a dramatic enhancement of particle uptake in rainbow trout phagocytes.

J Li·R Peters·S Lapatra·M Vazzana·J O Sunyer
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Abstract

Here we have identified a serum fraction containing approximately 8-kDa molecules with an unexpected capacity to greatly enhance particle uptake in trout head kidney leukocytes (HKLs). This approximately 8-kDa particle-uptake enhancing fraction (PUEF-8) was purified from complement-activated serum by gel filtration chromatography. Mass spectrometric analysis and reactivity of anti-trout C3-1 and C4 antibodies, indicated the presence of C3a, C4a and C5a molecules in PUEF-8. Using a newly developed flow cytometric assay that measures the capacity of cells to ingest fluorescent beads, we showed that PUEF-8 induced a striking enhancement (344+/-50% higher than the PBS control value) in the number of HKLs ingesting three or more beads. In contrast, the effect of PUEF-8 on peripheral blood leukocytes (PBLs) was almost negligible. Interestingly, PUEF-8 acted as a strong chemoattractant for both HKLs and PBLs. These findings suggest a novel role for the anaphylatoxins generated during complement activation in teleost fish.

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AnaphylatoxinsAnimalsCell MovementComplement System ProteinsFlow CytometryLeukocytesOncorhynchus mykissPhagocytesPhagocytosisTime FactorsJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.

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J Li, R Peters, S Lapatra, M Vazzana, J O Sunyer. 2004. Anaphylatoxin-like molecules generated during complement activation induce a dramatic enhancement of particle uptake in rainbow trout phagocytes.. https://doi.org/10.1016/j.dci.2004.03.004

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