Fig 1.
Schematic overview of nanoparticle synthesis (a) and timeline of animal study, sample preparation and analysis (b).
Created with BioRender.com.
Table 1.
Values for the specific surface area (SBET) pore diameter (Dpore) and pore volume (Vpore) for pure, amino-functionalized, and mPEG-modified MNPSNPs, obtained from nitrogen physisorption isotherms. Values for the hydrodynamic diameter (Dh), PDI and zeta-potential obtained from the dynamic light scattering experiments.
Fig 2.
TEM-images, Nitrogen physisorption isotherms and pore size distribution of MNPSNP.
TEM-images of MNPSNP before modification (a) and after amino functionalization (b) after PEG-modification (c) and CD-47-modification (d). Nitrogen physisorption isotherms (e) and pore size distribution (f) of MNPSNP, amino-functionalized MNPSNP, and mPEG-modified MNPSNP scale bar = 100 nm.
Fig 3.
Size distribution obtained by dynamic light scattering.
Particle size distribution of the MNPSNPs in the pathway of CD-47 modification (a). Particle size distribution of the MNPSNPs in the pathway of mPEG modification (b). Zeta potential distribution of mPEG-modified (c) and CD-47-modified MNPSNP with their respective pre-stages (d). Size distribution of the hydrodynamic diameter of CD-47-modified MNPSNP in FCS with FCS for reference (e).
Fig 4.
Release curve of CD-47-modified MNPSNPs (black) and amino-functionalized MNPSNP (grey) as control (MNPSNP-NH2).
Fig 5.
Exemplary fluorescent microscopy images of magnetic implants, fluorescence score values for the tissue surrounding the implants and percentage of red fluorescent area of the total implant surface.
Implant of an animal from the CD-47 group (a), enlarged section of (a) with green autofluorescent material (b, asterisks) and red fluorescent nanoparticles (b, arrows); magnetic implant of an animal from the PEG-group (c); titanium implant of an animal from the CD-47 group (d); titanium implant of an animal from the PEG-group (e). Varying parts of the implants are covered with autofluorescent material (asterisks) which resulted in exclusion of some implant surfaces, the quantity of nanoparticles differs on the different implant materials and for the different nanoparticle types but without statistical significance, scale bar = 500 µm. Box and whisker plots of fluorescence score values for the tissue surrounding the implants (f) and the percentage of red fluorescent area of the total implant surface (g) for the two groups and the different implant materials (left = magnetic implant, right = non-magnetic implant). The boxes represent the 25th to 75th percentiles, the solid line indicates the median, triangles mark values outside the inner fences, CD-47 group n = 14 (both sides), PEG-group n = 13 (left) and n = 12 (right).
Fig 6.
Box and whisker plots of the fluorescence score values of the inner organs and the tissue surrounding the implants.
Score values of liver (a), spleen (b), left kidney (c), lung (d), lymphnodes (e) and right kidney (f) as well as score values for inflammatory reaction (g), necrotic debris (h) and fibrosis (i) of the tissue surrounding the implants for the two different groups. The boxes represent the 25th to 75th percentiles, the solid line indicates the median, triangles mark values outside the inner fences, CD-47 group n = 13 (left) and n = 11 (right), PEG-group n = 13 (both sides).
Fig 7.
Exemplary light and fluorescence microscopic images of liver, lung and implantation site.
Fluorescence microscopic images of smaller more solitary nanoparticles in the liver (a) in contrast to bigger clusters of nanoparticles in the lung tissue (b). For this animal (CD-47-group) a score of 4 (moderate, ≥ 100 cluster) for nanoparticles in the lung and a score of 5 (to a high degree, ≥ 100, confluence) for nanoparticles in the liver according to Reifenrath et al. [21] was assigned, arrows mark RITC-labeled nanoparticles; Light microscopic image of HE stained slice of the former implantation site with inserted placeholder (*) of an animal from the PEG-group showing infiltration of inflammatory cells (black arrows), for this slide a score of 2 for inflammatory reaction, 1 for necrotic debris and 1 for fibrosis was assigned (c) fluorescence microscopic image of DAPI stained slice of the same former implantation site like in c (black box in c ), RITC-labeled nanoparticles in areas with infiltration of inflammatory cells (white arrows) (d) ; blue: nuclear staining with DAPI, red: RITC labeled MNPSNP; scale bar = 100 µm.