  We derive a microscopic relativistic point-coupling model of nuclear
many-body dynamics constrained by in-medium QCD sum rules and chiral symmetry.
The effective Lagrangian is characterized by density dependent coupling
strengths, determined by chiral one- and two-pion exchange and by QCD sum rule
constraints for the large isoscalar nucleon self-energies that arise through
changes of the quark condensate and the quark density at finite baryon density.
This approach is tested in the analysis of the equations of state for symmetric
and asymmetric nuclear matter, and of bulk and single-nucleon properties of
finite nuclei. In comparison with purely phenomenological mean-field
approaches, the built-in QCD constraints and the explicit treatment of pion
exchange restrict the freedom in adjusting parameters and functional forms of
density dependent couplings. It is shown that chiral (two-pion exchange)
fluctuations play a prominent role for nuclear binding and saturation, whereas
strong scalar and vector fields of about equal magnitude and opposite sign,
induced by changes of the QCD vacuum in the presence of baryonic matter,
generate the large effective spin-orbit potential in finite nuclei.
