FIGURE 7.

Modulation of NP cell-capture efficacy spectrum of the pristine material surface by host NP proteome and proper approach to identify opsonins. The intrinsic ability of NP chemical coatings to mediate the internalization by phagocytes can vary significantly, depending on charge, hydrophobicity, or other specific characteristics of the coating agents and polymers. The resulting spectrum of clearance efficacy (top) of possible surfaces in the no-protein medium is modified by the possible binding of host proteins to NPs in biofluids (left). This may result in up-modulation, down-modulation, or non-modulation of one defined NP cell capture compared with the one in the no-protein medium. However, the selective hampering of opsonins in complex medium, differently modulates the capture spectrum (right), allowing to evaluate the capture efficacy due to remaining dysopsonins. This comparison allows to unequivocally define the biological relevance in vitro of the identified specific opsonic factors and obtain relevant insights on the molecular mechanisms involved.