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Actin-based phagosome motility.

Fangliang Zhang·Frederick S Southwick·Daniel L Purich
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Abstract

Despite abundant evidence of actin's involvement at the particle internalization stage of phagocytosis, little is known about whether phagosomes undergo the same type of actin-based motility as observed with endocytic vesicles or such intracellular pathogens as Listeria and Shigella. By employing video microscopy to follow the fate of latex bead-containing phagosomes within the cytoplasm of bone marrow macrophages, we have made the novel observation of actin-based phagosome motility. Immunofluorescence microscopy confirmed that phagosomes containing IgG-opsonized, bovine serum albumin (or BSA) -coated or uncoated latex beads all formed actin-rich rocket tails that persisted only during a brief, 1-2 min period of actin-based motility. Average speeds of actin-based phagosome motility were 0.13 +/- 0.06 microm/s for IgG-coated beads, 0.14 +/- 0.04 microm/s for BSA-coated beads, and 0.11+/- 0.03 microm/s for uncoated beads. Moreover, the speeds and motile-phase duration of each type of phagosome were comparable to the behavior of pinosomes [Merrifield et al., 1999: Nat. Cell Biol. 1:72-74.]. Determination of optimal conditions for observing and analyzing actin-based phagosome motility should facilitate future investigations of phagocytosis and phagosome maturation.

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ActinsAnimalsBone Marrow CellsCattleCells, CulturedFemaleFluorescent DyesImmunoglobulin GMacrophagesMiceMice, Inbred C57BLMicroscopy, FluorescenceMicroscopy, VideoMicrospheresMovementPhagocytosisPhagosomesSerum Albumin, BovineJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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Fangliang Zhang, Frederick S Southwick, Daniel L Purich. 2002. Actin-based phagosome motility.. https://doi.org/10.1002/cm.10058

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