|
|
||||||||
Institute of Immunology and Allergology, Inselspital, Bern, Switzerland
Anaphylatoxin derived from the fifth complement component (C5a) in the presence of IL-3 induces continuous leukotriene C4 generation and IL-4 and IL-13 expression in human basophils for a period of 1618 h. This indicates that the G protein-coupled C5a receptor (C5aR) can induce long-lasting cellular responses. Using anti-N-terminal C5aR Abs, C-terminal C5a hexapeptide analogs, and pertussis toxin, we demonstrate that the putative activation site of the C5aR is both necessary and sufficient for these late cellular responses. Furthermore, continuous pertussis toxin-sensitive G protein-coupled receptor activation and receptor-ligand interaction is ongoing and required during the entire period of product release. However, the late basophil responses have a more stringent requirement for optimal receptor activation. Leukotriene C4 generation appears to be influenced mostly by the way the receptor is activated, because the most active hexapeptide is a superagonist for this response. By contrast, C5adesarg, lacking the C-terminal arginine, induces minimal lipid mediator formation but is fully active to induce IL-4 production and is even a superagonist for IL-13 release. Nevertheless, IL-4/IL-13 synthesis in response to C5adesarg could be blocked by both C-terminal antagonistic peptide as well as anti-N-terminal C5aR Abs, indicating only minor differences of ligand-receptor interactions between C5a and C5adesarg. Taken together, our data demonstrate that long-lasting and continuous signaling occurs through a limited activation domain of the C5aR, which can differentially promote separate basophil functions.
This article has been cited by other articles:
![]() |
A. C. Jacobson, J. J. Weis, and J. H. Weis Complement Receptors 1 and 2 Influence the Immune Environment in a B Cell Receptor-Independent Manner J. Immunol., April 1, 2008; 180(7): 5057 - 5066. [Abstract] [Full Text] [PDF] |
||||
![]() |
A.-M. Scola, A. Higginbottom, L. J. Partridge, R. C. Reid, T. Woodruff, S. M. Taylor, D. P. Fairlie, and P. N. Monk The Role of the N-terminal Domain of the Complement Fragment Receptor C5L2 in Ligand Binding J. Biol. Chem., February 9, 2007; 282(6): 3664 - 3671. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Tschopp, N. Spiegl, S. Didichenko, W. Lutmann, P. Julius, J. C. Virchow, C. E. Hack, and C. A. Dahinden Granzyme B, a novel mediator of allergic inflammation: its induction and release in blood basophils and human asthma Blood, October 1, 2006; 108(7): 2290 - 2299. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Higginbottom, S. A. Cain, T. M. Woodruff, L. M. Proctor, P. K. Madala, J. D. A. Tyndall, S. M. Taylor, D. P. Fairlie, and P. N. Monk Comparative Agonist/Antagonist Responses in Mutant Human C5a Receptors Define the Ligand Binding Site J. Biol. Chem., May 6, 2005; 280(18): 17831 - 17840. [Abstract] [Full Text] [PDF] |
||||
![]() |
R. Baelder, B. Fuchs, W. Bautsch, J. Zwirner, J. Kohl, H. G Hoymann, T. Glaab, V. Erpenbeck, N. Krug, and A. Braun Pharmacological Targeting of Anaphylatoxin Receptors during the Effector Phase of Allergic Asthma Suppresses Airway Hyperresponsiveness and Airway Inflammation J. Immunol., January 15, 2005; 174(2): 783 - 789. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Otto, H. Hawlisch, P. N. Monk, M. Muller, A. Klos, C. L. Karp, and J. Kohl C5a Mutants Are Potent Antagonists of the C5a Receptor (CD88) and of C5L2: POSITION 69 IS THE LOCUS THAT DETERMINES AGONISM OR ANTAGONISM J. Biol. Chem., January 2, 2004; 279(1): 142 - 151. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Schramm, F. H. Falcone, A. Gronow, K. Haisch, U. Mamat, M. J. Doenhoff, G. Oliveira, J. Galle, C. A. Dahinden, and H. Haas Molecular Characterization of an Interleukin-4-inducing Factor from Schistosoma mansoni Eggs J. Biol. Chem., May 9, 2003; 278(20): 18384 - 18392. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. C. La Flamme, A. S. MacDonald, C. R. Huxtable, M. Carroll, and E. J. Pearce Lack of C3 Affects Th2 Response Development and the Sequelae of Chemotherapy in Schistosomiasis J. Immunol., January 1, 2003; 170(1): 470 - 476. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Drouin, D. B. Corry, T. J. Hollman, J. Kildsgaard, and R. A. Wetsel Absence of the Complement Anaphylatoxin C3a Receptor Suppresses Th2 Effector Functions in a Murine Model of Pulmonary Allergy J. Immunol., November 15, 2002; 169(10): 5926 - 5933. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. Arock, E. Schneider, M. Boissan, V. Tricottet, and M. Dy Differentiation of human basophils: an overview of recent advances and pending questions J. Leukoc. Biol., April 1, 2002; 71(4): 557 - 564. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. A. Cain and P. N. Monk The Orphan Receptor C5L2 Has High Affinity Binding Sites for Complement Fragments C5a and C5a des-Arg74 J. Biol. Chem., February 22, 2002; 277(9): 7165 - 7169. [Abstract] [Full Text] [PDF] |
||||
![]() |
S. M. Drouin, D. B. Corry, J. Kildsgaard, and R. A. Wetsel Cutting Edge: The Absence of C3 Demonstrates a Role for Complement in Th2 Effector Functions in a Murine Model of Pulmonary Allergy J. Immunol., October 15, 2001; 167(8): 4141 - 4145. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |