Limits...
VAMP8-dependent fusion of recycling endosomes with the plasma membrane facilitates T lymphocyte cytotoxicity.

Marshall MR, Pattu V, Halimani M, Maier-Peuschel M, Müller ML, Becherer U, Hong W, Hoth M, Tschernig T, Bryceson YT, Rettig J - J. Cell Biol. (2015)

Bottom Line: Although multiple SNARE proteins have been implicated in cytotoxic granule exocytosis, the role of vesicular SNARE proteins, i.e., vesicle-associated membrane proteins (VAMPs), remains enigmatic.In primary human CTLs, however, VAMP8 colocalized with Rab11a-positive recycling endosomes.Our findings imply that secretory granule exocytosis pathways in other cell types may also be more complex than previously appreciated.

View Article: PubMed Central - HTML - PubMed

Affiliation: Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany Department of Medicine, Center For Infectious Medicine, 14186 Stockholm, Sweden.

Show MeSH

Related in: MedlinePlus

VAMP8 does not colocalize with cytotoxic granule constituents in human CTLs. (A and B) SIM images depicting VAMP8 localization in unconjugated (A) or SEA-target cell-conjugated (B) human CTLs stained with anti-VAMP8 and anti–granzyme B (GzmB). (C and D) SIM images depicting VAMP8 localization in unconjugated (C) or SEA-target cell-conjugated (D) CTLs stained with anti-VAMP8 and anti-perforin. (C) SIM images of resting human CTL stained with anti-VAMP8 and anti-perforin. For SEA-target cell-conjugated CTLs, the Pearson’s coefficient for VAMP8 versus perforin was r = 0.28 (n = 10). Bars, 2.5 µm.
© Copyright Policy - openaccess
Related In: Results  -  Collection

License 1 - License 2
getmorefigures.php?uid=PMC4493996&req=5

fig2: VAMP8 does not colocalize with cytotoxic granule constituents in human CTLs. (A and B) SIM images depicting VAMP8 localization in unconjugated (A) or SEA-target cell-conjugated (B) human CTLs stained with anti-VAMP8 and anti–granzyme B (GzmB). (C and D) SIM images depicting VAMP8 localization in unconjugated (C) or SEA-target cell-conjugated (D) CTLs stained with anti-VAMP8 and anti-perforin. (C) SIM images of resting human CTL stained with anti-VAMP8 and anti-perforin. For SEA-target cell-conjugated CTLs, the Pearson’s coefficient for VAMP8 versus perforin was r = 0.28 (n = 10). Bars, 2.5 µm.

Mentions: We set out to decipher how VAMP8 may facilitate cytotoxic granule exocytosis. In contrast to studies of mouse CTL (Loo et al., 2009), we found VAMP8 localization to be distinct from that of granzyme B in unconjugated, fixed human primary CTLs using SIM (Fig. 2 A). Of note, VAMP8-carrying compartments were more numerous than those with granzyme B. Upon conjugation with SEA-pulsed target cells, VAMP8-carrying vesicles did not start to colocalize with those containing granzyme B (Fig. 2 B). Similarly, VAMP8-carrying vesicles did not colocalize with perforin-containing vesicles in unconjugated or conjugated CTLs (Fig. 2, C and D). Unexpectedly, we conclude that VAMP8 localized to a compartment distinct from cytotoxic granules in human CTLs.


VAMP8-dependent fusion of recycling endosomes with the plasma membrane facilitates T lymphocyte cytotoxicity.

Marshall MR, Pattu V, Halimani M, Maier-Peuschel M, Müller ML, Becherer U, Hong W, Hoth M, Tschernig T, Bryceson YT, Rettig J - J. Cell Biol. (2015)

VAMP8 does not colocalize with cytotoxic granule constituents in human CTLs. (A and B) SIM images depicting VAMP8 localization in unconjugated (A) or SEA-target cell-conjugated (B) human CTLs stained with anti-VAMP8 and anti–granzyme B (GzmB). (C and D) SIM images depicting VAMP8 localization in unconjugated (C) or SEA-target cell-conjugated (D) CTLs stained with anti-VAMP8 and anti-perforin. (C) SIM images of resting human CTL stained with anti-VAMP8 and anti-perforin. For SEA-target cell-conjugated CTLs, the Pearson’s coefficient for VAMP8 versus perforin was r = 0.28 (n = 10). Bars, 2.5 µm.
© Copyright Policy - openaccess
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4493996&req=5

fig2: VAMP8 does not colocalize with cytotoxic granule constituents in human CTLs. (A and B) SIM images depicting VAMP8 localization in unconjugated (A) or SEA-target cell-conjugated (B) human CTLs stained with anti-VAMP8 and anti–granzyme B (GzmB). (C and D) SIM images depicting VAMP8 localization in unconjugated (C) or SEA-target cell-conjugated (D) CTLs stained with anti-VAMP8 and anti-perforin. (C) SIM images of resting human CTL stained with anti-VAMP8 and anti-perforin. For SEA-target cell-conjugated CTLs, the Pearson’s coefficient for VAMP8 versus perforin was r = 0.28 (n = 10). Bars, 2.5 µm.
Mentions: We set out to decipher how VAMP8 may facilitate cytotoxic granule exocytosis. In contrast to studies of mouse CTL (Loo et al., 2009), we found VAMP8 localization to be distinct from that of granzyme B in unconjugated, fixed human primary CTLs using SIM (Fig. 2 A). Of note, VAMP8-carrying compartments were more numerous than those with granzyme B. Upon conjugation with SEA-pulsed target cells, VAMP8-carrying vesicles did not start to colocalize with those containing granzyme B (Fig. 2 B). Similarly, VAMP8-carrying vesicles did not colocalize with perforin-containing vesicles in unconjugated or conjugated CTLs (Fig. 2, C and D). Unexpectedly, we conclude that VAMP8 localized to a compartment distinct from cytotoxic granules in human CTLs.

Bottom Line: Although multiple SNARE proteins have been implicated in cytotoxic granule exocytosis, the role of vesicular SNARE proteins, i.e., vesicle-associated membrane proteins (VAMPs), remains enigmatic.In primary human CTLs, however, VAMP8 colocalized with Rab11a-positive recycling endosomes.Our findings imply that secretory granule exocytosis pathways in other cell types may also be more complex than previously appreciated.

View Article: PubMed Central - HTML - PubMed

Affiliation: Cellular Neurophysiology, Center for Integrative Physiology and Molecular Medicine, Saarland University, 66421 Homburg, Germany Department of Medicine, Center For Infectious Medicine, 14186 Stockholm, Sweden.

Show MeSH
Related in: MedlinePlus