Cells of the dendritic family are suited to perform two distinct functions
at two discrete locations. in the peripheral tissues, DC act as sentinels f
or "dangerous" antigens. They then migrate into the lymphoid organ, where t
hey initiate activation of T lymphocytes which are specific for these antig
ens. During their migration, DC shift from an antigen-capturing-mode to a T
cell sensitizing mode. In addition to switching on the immune response, su
btypes of DC appear to influence the character of T cell differentiation, i
.e. the Th1/Th2 balance. (C) 2001 Editions scientifiques et medicales Elsev
ier SAS.