Abstract
We report here that human B cells produce thymus
and activation-regulated chemokine
(TARC/CCL17) and macrophage derived
chemokine (MDC/CCL22) if stimulated with anti-
CD40 and IL-4. The production was determined by
both protein and mRNA level using specific ELISA
and semi-quantitative RT-PCR methods. Since
the ligand of the TARC and MDC is CCR4, which is
specifically expressed on Th2 type T cells, the production
of these CC chemokines is likely to play
important roles in the T cell and B cell interaction.
Consistent with this, ovalbumin (OVA) specific
IgE levels, which reflect the T-B cell interaction, are
significantly correlated with the amounts of TARC
and MDC in sera. Furthermore, we found that
TARC and MDC levels are significantly increased in
the sera obtained from patients with atopic dermatitis,
and that the amounts are correlated with
the severity of atopic dermatitis.
Since CD40 ligand and IL-4 are produced by activated
T helper cells, these results indicate that
TARC and MDC produced by B cells play important
roles in the production of antigen specific IgE by
the T-B cell interaction and in the pathogenesis of
allergic disease.
