A number of studies have implicated a role for the cell surface
glycoprotein CD44 in several biologic events, such as lymphopoiesis,
homing, lymphocyte activation, and apoptosis. We have earlier
reported that signaling via CD44 on naive B cells in addition
to B-cell receptor (BCR) and CD40 engagement generated a germinal
center-like phenotype. To further characterize the global role
of CD44 in B differentiation, we examined the expression profile
of human B cells cultured in vitro in the presence or absence
of CD44 ligation, together with anti-immunoglobulin (anti-Ig)
and anti-CD40 antibodies. The data sets derived from DNA microarrays
were analyzed using a novel statistical analysis scheme created
to retrieve the most likely expression pattern of CD44 ligation.
Our results show that genes such as interleukin-6 (IL-6), IL-1alpha,
and beta(2)-adrenergic receptor (beta(2)-AR) were specifically
up-regulated by CD44 ligation, suggesting a novel role for CD44
in immunoregulation and inflammation.