|
|
 Previous Article | Table of Contents | Next Article 
B-cell homotypic adhesion through exon-A restricted epitopes of CD45
involves LFA-1/ICAM-1, ICAM-3 interactions, and induces coclustering of
CD45 and LFA-1
JM Zapata, MR Campanero, M Marazuela, F Sanchez-Madrid and MO de Landazuri
Servicio de Inmunologia, Hospital de la Princesa, Universidad Autonoma de
Madrid, Spain.
Lymphocyte interactions with other leukocytes and other cell types, as well
as with components of the extracellular matrix, are one of the key steps in
the immune response. Three novel monoclonal antibodies (MoAbs) have been
produced and selected for their ability to induce intercellular adhesion in
B cells. These three MoAbs immunoprecipitated a polypeptide of 220 kD,
displaying specific phosphotyrosine phosphatase activity that has been
identified as CD45. These MoAbs recognize epitopes located on the
alternative spliced exon-A-encoded region of CD45. These epitopes are of
polypeptidic nature, but they can be masked by addition of carbohydrate
during CD45 biosynthesis. Interestingly enough, CD45 epitopes recognized by
these MoAbs appeared to be selectively expressed on both peripheral blood
and tonsillar B lymphocytes as well as on peripheral blood natural killer
(NK) cells. CD45-mediated intercellular adhesion was abrogated upon
incubation with anti-leukocyte function-associated antigen 1 (anti-LFA-1),
intercellular cell adhesion molecule 1 (ICAM-1), and ICAM-3 MoAbs, thus
indicating that this phenomenon involved both LFA-1/ICAM-1 and LFA-
1/ICAM-3 cell adhesion pathways. Moreover, CD45-mediated cell aggregation
was also inhibited by preincubation with some conventional anti-CD45 MoAbs.
Interestingly, the triggering of cell aggregation through CD45 induced
membrane surface relocation of CD45 and LFA-1 molecules, with both of them
colocalizing at cell-cell contact areas of B-cell aggregates. Studies with
inhibitors of both phosphotyrosine phosphatase and tyrosine kinase
activities suggest that CD45 phosphotyrosine phosphatase activity could be
involved in CD45-mediated cell aggregation. Taken together, these results
support the notion that CD45 is a key molecule in the regulation of
LFA-1-mediated cell-cell interactions.
Volume 86,
Issue 5,
pp. 1861-1872,
09/01/1995
Copyright © 1995 by The American Society of Hematology
 CiteULike  Connotea  Del.icio.us  Digg  Reddit  Technorati What's this?
This article has been cited by other articles:
|
|
|
|
 
S. A. Johnson, S. J. Rozzo, and J. C. Cambier
Aging-Dependent Exclusion of Antigen-Inexperienced Cells from the Peripheral B Cell Repertoire
J. Immunol.,
May 15, 2002;
168(10):
5014 - 5023.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
L. B. Dustin, D. R. Plas, J. Wong, Y. T. Hu, C. Soto, A. C. Chan, and M. L. Thomas
Expression of Dominant-Negative Src-Homology Domain 2-Containing Protein Tyrosine Phosphatase-1 Results in Increased Syk Tyrosine Kinase Activity and B Cell Activation
J. Immunol.,
March 1, 1999;
162(5):
2717 - 2724.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
S. Sembries, H. Pahl, S. Stilgenbauer, H. Dohner, and F. Schriever
Reduced Expression of Adhesion Molecules and Cell Signaling Receptors by Chronic Lymphocytic Leukemia Cells With 11q Deletion
Blood,
January 15, 1999;
93(2):
624 - 631.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
|
|
R. S. Larson, D. C. Brown, and L. A. Sklar
Retinoic Acid Induces Aggregation of the Acute Promyelocytic Leukemia Cell Line NB-4 by Utilization of LFA-1 and ICAM-2
Blood,
October 1, 1997;
90(7):
2747 - 2756.
[Abstract]
[Full Text]
[PDF]
|
|
|
|
|
