|
|
Blood, 15 February 2005, Vol. 105, No. 4, pp. 1546-1548.
Prepublished online as a Blood First Edition Paper on October 12, 2004; DOI 10.1182/blood-2004-05-1886.
Previous Article | Table of Contents | Next Article 
HEMOSTASIS, THROMBOSIS, AND VASCULAR BIOLOGY Brief report
Monoclonal antibodies that mimic the action of anti-D in the amelioration of murine ITP act by a mechanism distinct from that of IVIg
Seng Song,
Andrew R. Crow,
Vinayakumar Siragam,
John Freedman, and
Alan H. Lazarus
From the Transfusion Medicine Research, St Michael's Hospital; The Canadian Blood Services; and The Toronto Platelet Immunobiology Group, Toronto, ON, Canada.
The mechanism of action of intravenous immunoglobulin (IVIg) and polyclonal anti-Dmediated reversal of immune thrombocytopenia (ITP) is still unclear. However, in a murine model of ITP, the therapeutic effect of IVIg appears to be wholly dependent upon the expression of the inhibitory Fc receptor, Fc RIIB. We previously demonstrated that, similar to anti-D in humans, 2 erythrocyte-reactive monoclonal antibodies (TER119 and M1/69) ameliorated murine ITP and inhibited reticuloendothelial system (RES) function at doses that protected against thrombocytopenia. The current study evaluated the involvement of the inhibitory and activating Fc receptors, Fc RIIB and Fc RIIIA, respectively, in the TER119 and M1/69-mediated inhibition of thrombocytopenia. In contrast to IVIg, in Fc RIIB-deficient mice, both monoclonal antibodies ameliorated ITP and both significantly down-regulated the level of expression of the activating Fc RIIIA in splenic macrophages. These results indicate that anti-erythrocyte antibodies that ameliorate ITP act independently of Fc RIIB expression but are dependent upon the activating Fc RIIIA.

CiteULike Connotea Del.icio.us Digg Reddit Technorati What's this?
This article has been cited by other articles:

|
 |

|
 |
 
Y. Li, M. E. Williams, J. B. Cousar, A. W. Pawluczkowycz, M. A. Lindorfer, and R. P. Taylor
Rituximab-CD20 Complexes Are Shaved from Z138 Mantle Cell Lymphoma Cells in Intravenous and Subcutaneous SCID Mouse Models
J. Immunol.,
September 15, 2007;
179(6):
4263 - 4271.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
A. R. Crow, S. Song, J. W. Semple, J. Freedman, and A. H. Lazarus
A role for IL-1 receptor antagonist or other cytokines in the acute therapeutic effects of IVIg?
Blood,
January 1, 2007;
109(1):
155 - 158.
[Abstract]
[Full Text]
[PDF]
|
 |
|

|
 |

|
 |
 
D. B. Cines and J. B. Bussel
How I treat idiopathic thrombocytopenic purpura (ITP)
Blood,
October 1, 2005;
106(7):
2244 - 2251.
[Full Text]
[PDF]
|
 |
|
|
|