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Eosinophil granulocyte interaction with serum-opsonized particles: binding and degranulation are enhanced by tumor necrosis factor alpha

Egesten, Arne LU ; Blom, M; Calafat, J; Janssen, H and Knol, E F (1998) In International Archives of Allergy and Immunology 115(2). p.121-128
Abstract
Eosinophils participate in the inflammatory response seen in allergy and helminthic infestation. Their release of granule-bound cationic proteins may play a role in these diseases. Therefore, we investigated mechanisms involved in the release of eosinophil cationic protein (ECP). Serum-opsonized zymosan was phagocytosed by eosinophils, and ECP was released into the phagosomes as judged by immunoelectron microscopy. Degranulation to the external milieu was induced by serum-opsonized, non-phagocytosable Sephadex beads (SOS), and ECP release was determined by use of an enzyme-linked immunosorbent assay. CD11b, CD18, and CD32 monoclonal antibodies inhibited degranulation, demonstrating dependence on complement receptor type 3 (CR3), and the... (More)
Eosinophils participate in the inflammatory response seen in allergy and helminthic infestation. Their release of granule-bound cationic proteins may play a role in these diseases. Therefore, we investigated mechanisms involved in the release of eosinophil cationic protein (ECP). Serum-opsonized zymosan was phagocytosed by eosinophils, and ECP was released into the phagosomes as judged by immunoelectron microscopy. Degranulation to the external milieu was induced by serum-opsonized, non-phagocytosable Sephadex beads (SOS), and ECP release was determined by use of an enzyme-linked immunosorbent assay. CD11b, CD18, and CD32 monoclonal antibodies inhibited degranulation, demonstrating dependence on complement receptor type 3 (CR3), and the low-affinity Fc receptor for IgG. Tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL)-5 both rapidly enhanced the binding of eosinophils to serum-opsonized zymosan, and also the release of ECP upon interaction with SOS. The cytokine-induced increase in ECP release was inhibited by the phospholipase A2 (PLA2) inhibitor mepacrine, indicating an involvement of PLA2 in the enhanced response but not in baseline degranulation. Autocrine stimulation by the platelet-activating factor (PAF) is unlikely since the PAF receptor antagonist WEB 2086 did not inhibit the enhanced response. In conclusion, the main signals for eosinophil degranulation on serum-opsonized particles are mediated by CR3 and receptors for immunoglobulins. As for IL-5, TNF-alpha changes eosinophil phenotype from a resting to an activated state. (Less)
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author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
International Archives of Allergy and Immunology
volume
115
issue
2
pages
121 - 128
publisher
Karger
external identifiers
  • Scopus:0031963722
ISSN
1423-0097
DOI
10.1159/000023891
language
English
LU publication?
yes
id
f7bf721f-6854-4a32-b80c-0f911cecd00e (old id 1296504)
date added to LUP
2009-07-30 15:41:08
date last changed
2017-01-01 07:57:13
@article{f7bf721f-6854-4a32-b80c-0f911cecd00e,
  abstract     = {Eosinophils participate in the inflammatory response seen in allergy and helminthic infestation. Their release of granule-bound cationic proteins may play a role in these diseases. Therefore, we investigated mechanisms involved in the release of eosinophil cationic protein (ECP). Serum-opsonized zymosan was phagocytosed by eosinophils, and ECP was released into the phagosomes as judged by immunoelectron microscopy. Degranulation to the external milieu was induced by serum-opsonized, non-phagocytosable Sephadex beads (SOS), and ECP release was determined by use of an enzyme-linked immunosorbent assay. CD11b, CD18, and CD32 monoclonal antibodies inhibited degranulation, demonstrating dependence on complement receptor type 3 (CR3), and the low-affinity Fc receptor for IgG. Tumor necrosis factor-alpha (TNF-alpha) and interleukin (IL)-5 both rapidly enhanced the binding of eosinophils to serum-opsonized zymosan, and also the release of ECP upon interaction with SOS. The cytokine-induced increase in ECP release was inhibited by the phospholipase A2 (PLA2) inhibitor mepacrine, indicating an involvement of PLA2 in the enhanced response but not in baseline degranulation. Autocrine stimulation by the platelet-activating factor (PAF) is unlikely since the PAF receptor antagonist WEB 2086 did not inhibit the enhanced response. In conclusion, the main signals for eosinophil degranulation on serum-opsonized particles are mediated by CR3 and receptors for immunoglobulins. As for IL-5, TNF-alpha changes eosinophil phenotype from a resting to an activated state.},
  author       = {Egesten, Arne and Blom, M and Calafat, J and Janssen, H and Knol, E F},
  issn         = {1423-0097},
  language     = {eng},
  number       = {2},
  pages        = {121--128},
  publisher    = {Karger},
  series       = {International Archives of Allergy and Immunology},
  title        = {Eosinophil granulocyte interaction with serum-opsonized particles: binding and degranulation are enhanced by tumor necrosis factor alpha},
  url          = {http://dx.doi.org/10.1159/000023891},
  volume       = {115},
  year         = {1998},
}