Differential Effects of Chondroitin Sulfates A and B on Monocyte and
B-Cell Activation: Evidence for B-Cell Activation Via a CD44-Dependent
Pathway
Jacob Rachmilewitz and
Mark L. Tykocinski
From the Department of Pathology, Case Western Reserve University,
Cleveland, OH.
At inflammatory sites, proteoglycans are both secreted by activated
mononuclear leukocytes and released as a consequence of extracellular
matrix degradation. Chondroitin 4-sulfate proteoglycans constitute
the predominant ones produced by activated human monocytes/macrophages. In this study, we show that two chondroitin 4-sulfate forms, CSA and
CSB, can activate distinct peripheral blood mononuclear cell types.
Whereas CSA activates monocytes (to secrete monokines), CSB activates
B-cells (to proliferate). In contrast, the chondroitin 6-sulfate CSC
and heparin do not exert these functional effects. We further show that
CD44 monoclonal antibodies block CSB-induced B-cell proliferation.
These findings point to glycosaminoglycans, and specifically
chondroitin 4-sulfates, as a novel class of immunological mediators at
inflammatory sites. Furthermore, the data link CD44 to B-cell
activation, paralleling the established roles of CD44 in T-cell and
monocyte activation.
Blood, Vol. 92 No. 1 (July 1), 1998:
pp. 223-229
© 1998 by The American Society of Hematology.
