  An interesting breakthrough in understanding the elusive inner content of
nuclear systems in terms of partonic degrees of freedom is represented by
deeply virtual Compton scattering processes. In such a way, tomographic view of
nuclei and bound nucleons in coordinate space could be achieved for the first
time. Moreover, nowadays experimental results for such a process considering
$^4$He targets recently released at Jefferson Lab are available. In this talk,
the recent results of our rigorous Impulse Approximation for DVCS off $^4$He,
in terms of state-of-the-art models of the nuclear spectral function and of the
parton structure of the bound proton, able to explain present data, has been
shown.
