CXCR2- and E-selectin-induced neutrophil arrest during inflammation in vivo - PubMed (original) (raw)

Comparative Study

CXCR2- and E-selectin-induced neutrophil arrest during inflammation in vivo

Michael L Smith et al. J Exp Med. 2004.

Abstract

The signaling events leading to the activation of integrins and firm arrest of rolling neutrophils in inflamed venules have yet to be elucidated. In vitro assays suggest that both E-selectin and chemokines can trigger arrest of rolling neutrophils, but E-selectin(-/-) mice have normal levels of adherent neutrophils in inflamed venules. To test whether chemokine-induced neutrophil arrest in vivo can be unmasked by blocking E-selectin, we investigated neutrophil adhesion in inflamed cremaster muscle venules in tumor necrosis factor (TNF)-alpha-treated CXCR2(-/-) or wild-type (WT) mice injected with E-selectin blocking monoclonal antibody (mAb) 9A9. To block chemokine receptor signaling, we investigated E-selectin(-/-) or WT mice treated with pertussis toxin (PTx) intravenously. Neutrophil adhesion was unchanged in CXCR2(-/-), E-selectin(-/-), PTx-treated WT, or mAb 9A9-treated WT mice. However, TNF-alpha-induced neutrophil adhesion was almost completely abrogated in E-selectin(-/-) mice treated with PTx and significantly reduced in CXCR2(-/-) mice treated with the E-selectin blocking mAb. In thioglycollate-induced peritonitis, PTx treatment blocked neutrophil recruitment into the peritoneum of E-selectin(-/-) mice, but had only a partial effect in WT animals. These data show that E-selectin- and chemokine-mediated arrest mechanisms are overlapping in this model and identify CXCR2 as an important neutrophil arrest chemokine in vivo.

PubMed Disclaimer

Figures

Figure 1.

Figure 1.

Adherent leukocytes per 200-μm length of vessel (increase above background; A) and percent reduction in leukocyte rolling flux (B) due to injection of 600 ng KC into the carotid artery cannula. Data was acquired 1 min before and after injection into WT (7 venules in 3 mice; white bars), WT plus 4 μg PTx 3 h before cremaster exteriorization (10 venules in 4 mice; light gray bars), E-selectin−/− (6 venules in 2 mice; dark gray bars), and E-selectin−/− plus PTx (5 venules in 2 mice; black bars). *, P < 0.05 versus WT control (A) or rolling flux before KC injection (B).

Figure 2.

Figure 2.

Numbers of adherent cells per mm2 in murine cremaster muscle venules. Cremaster muscle exteriorized 3 h after intrascrotal injection of 500 ng TNF-α in WT (11 venules in 3 mice), WT plus 4 μg PTx 5 min before TNF-α injection (12 venules in 3 mice), E-selectin−/− (13 venules in 3 mice), E-selectin−/− plus PTx (17 venules in 3 mice), and WT plus PTx plus 60 μg α–E-selectin mAb 9A9 5 min before TNF-α injection (10 venules in 2 mice) using mice on a C57Bl/6 background (A), and WT (11 venules in 2 mice), CXCR2−/− (13 venules in 3 mice), and CXCR2−/− plus mAb 9A9 (11 venules in 2 mice) using mice on a BALB/c background (B). *, P < 0.05 versus all other groups.

Figure 3.

Figure 3.

Peritoneal neutrophil influx 4 h after 1 ml injection of 4% thioglycollate into WT (five mice; open circles), WT plus 4 μg PTx 3 h before thioglycollate injection (four mice; light gray circles), E-selectin−/− (four mice; dark gray bars), and E-selectin−/− plus PTx (five mice; closed diamonds). Data expressed as numbers of neutrophils (×103) per ml peritoneal lavage fluid counted using Kimura-stained samples. *, P < 0.05.

Similar articles

Cited by

References

    1. Springer, T.A. 1995. Traffic signals on endothelium for lymphocyte recirculation and leukocyte emigration. Annu. Rev. Physiol. 57:827–872. - PubMed
    1. Kunkel, E.J., J.L. Dunne, and K. Ley. 2000. Leukocyte arrest during cytokine-dependent inflammation in vivo. J. Immunol. 164:3301–3308. - PubMed
    1. Constantin, G., M. Majeed, C. Giagulli, L. Piccio, J.Y. Kim, E.C. Butcher, and C. Laudanna. 2000. Chemokines trigger immediate β2 integrin affinity and mobility changes: differential regulation and roles in lymphocyte arrest under flow. Immunity. 13:759–769. - PubMed
    1. Rainger, G.E., A.C. Fisher, and G.B. Nash. 1997. Endothelial-borne platelet-activating factor and interleukin-8 rapidly immobilize rolling neutrophils. Am. J. Physiol. 272:H114–H122. - PubMed
    1. Simon, S.I., Y. Hu, D. Vestweber, and C.W. Smith. 2000. Neutrophil tethering on E-selectin activates β2 integrin binding to ICAM-1 through a mitogen-activated protein kinase signal transduction pathway. J. Immunol. 164:4348–4358. - PubMed

Publication types

MeSH terms

Substances

Grants and funding

LinkOut - more resources