  In this paper we present new chemo-spectro-photometric models of elliptical
galaxies in which infall of primordial gas is allowed to occur. They aim to
simulate the collapse of a galaxy made of two components, i.e. luminous
material and dark matter. The mass of the dark component is assumed to be
constant in time, whereas that of the luminous material is supposed to accrete
at a suitable rate. They also include the effect of galactic winds powered by
supernova explosions and stellar winds from massive, early-type stars. The
models are constrained to match a number of properties of elliptical galaxies,
i.e. the slope and mean colours of the colour-magnitude relation (CMR), V
versus (V--K), the UV excess as measured by the colour (1550--V) together with
the overall shape of the integrated spectral energy distribution (ISED) in the
ultraviolet, the relation between the Mg2 index and (1550--V), the mass to blue
luminosity ratio M/Lb as a function of the B luminosity, and finally the
broad-band colours (U--B), (B--V), (V--I), (V--K), etc.
