  We discuss properties of particles and fields in a multi-dimensional
space-time, where the geometrization of gauge interactions can be performed.
For instance, in a 5-dimensional Kaluza-Klein manifold we argue that the motion
of charged spinning bodies is obtain in a Papapetrou-like formulation. As far
as spinors are concerned, we outline how the gauge coupling can be recognized
by a proper dependence on extra-coordinates and by the dimensional reduction
procedure.
