Limits...
Growth factor choice is critical for successful functionalization of nanoparticles.

Pinkernelle J, Raffa V, Calatayud MP, Goya GF, Riggio C, Keilhoff G - Front Neurosci (2015)

Bottom Line: Nanoparticles (NPs) show new characteristics compared to the corresponding bulk material.It also shows that successful functionalization of magnetic NPs with growth factors is dependent on the used binding chemistry and that it is hardly predictable.For use as therapeutics, functionalization strategies have to be reproducible and future studies are needed.

View Article: PubMed Central - PubMed

Affiliation: Department of Nephrology and Hypertension, Diabetes and Endocrinology, Otto-von-Guericke University of Magdeburg Magdeburg, Germany ; Institute for Biochemistry and Cell Biology, Otto-von-Guericke University of Magdeburg Magdeburg, Germany.

ABSTRACT
Nanoparticles (NPs) show new characteristics compared to the corresponding bulk material. These nanoscale properties make them interesting for various applications in biomedicine and life sciences. One field of application is the use of magnetic NPs to support regeneration in the nervous system. Drug delivery requires a functionalization of NPs with bio-functional molecules. In our study, we functionalized self-made PEI-coated iron oxide NPs with nerve growth factor (NGF) and glial cell-line derived neurotrophic factor (GDNF). Next, we tested the bio-functionality of NGF in a rat pheochromocytoma cell line (PC12) and the bio-functionality of GDNF in an organotypic spinal cord culture. Covalent binding of NGF to PEI-NPs impaired bio-functionality of NGF, but non-covalent approach differentiated PC12 cells reliably. Non-covalent binding of GDNF showed a satisfying bio-functionality of GDNF:PEI-NPs, but turned out to be unstable in conjugation to the PEI-NPs. Taken together, our study showed the importance of assessing bio-functionality and binding stability of functionalized growth factors using proper biological models. It also shows that successful functionalization of magnetic NPs with growth factors is dependent on the used binding chemistry and that it is hardly predictable. For use as therapeutics, functionalization strategies have to be reproducible and future studies are needed.

No MeSH data available.


Related in: MedlinePlus

Analysis of GDNF-functionality of GDNF:PEI-NPs. Cultures were cultivated with GDNF supplemented to the media (100 or 50 ng/ml GDNF) as controls, without any GDNF supplement or with GDNF:PEI-NPs in the media. The total number of neurons (A, mean ± SEM) decreased in cultures without GDNF supplement, but there were no changes in the number of surviving neurons with incubation of GDNF:PEI-NPs compared to the controls. The same result was found concerning the number of surviving motor neuron (B, mean ± SEM). Corresponding fluorescent anti-pan-neurofilament staining of control culture (C), culture cultivated without GDNF (D) and culture with GDNF:PEI-NPs (E). Bars = 500 μm. Significance differences are marked with * and demonstrate p < 0.05.
© Copyright Policy
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4557102&req=5

Figure 4: Analysis of GDNF-functionality of GDNF:PEI-NPs. Cultures were cultivated with GDNF supplemented to the media (100 or 50 ng/ml GDNF) as controls, without any GDNF supplement or with GDNF:PEI-NPs in the media. The total number of neurons (A, mean ± SEM) decreased in cultures without GDNF supplement, but there were no changes in the number of surviving neurons with incubation of GDNF:PEI-NPs compared to the controls. The same result was found concerning the number of surviving motor neuron (B, mean ± SEM). Corresponding fluorescent anti-pan-neurofilament staining of control culture (C), culture cultivated without GDNF (D) and culture with GDNF:PEI-NPs (E). Bars = 500 μm. Significance differences are marked with * and demonstrate p < 0.05.

Mentions: First, we tested for bio-functionality of GDNF:PEI-NPs after coupling. For this, we analyzed the number of surviving motor neurons in organotypic spinal cord cultures incubated with these NPs instead of GDNF supplement via media. GDNF:PEI-NPs were able to keep motor neuronal populations alive. There were no significant differences in the total number of surviving neurons or in the number of motor neurons between controls containing 100 or 50 ng/ml GDNF in the media and GDNF:PEI-NPs incubated cultures (Figures 4A,B). Parallel handled cultures that were cultivated without GDNF supplement displayed significantly less surviving neurons in the total number and in the number of motor neurons than controls 100 (100 ng/ml GDNF supplement). Figures 4C–E show corresponding immunofluorescent stainings for anti-pan-neurofilament. Controls and cultures, incubated with GDNF:PEI-NPs illustrated a prominent motor neuronal population (Figures 4C,E). Cultures without GDNF supplement displayed a clear reduction of stained motor neurons (Figure 4D). Accordingly, GDNF function was kept during coupling to the PEI-NPs.


Growth factor choice is critical for successful functionalization of nanoparticles.

Pinkernelle J, Raffa V, Calatayud MP, Goya GF, Riggio C, Keilhoff G - Front Neurosci (2015)

Analysis of GDNF-functionality of GDNF:PEI-NPs. Cultures were cultivated with GDNF supplemented to the media (100 or 50 ng/ml GDNF) as controls, without any GDNF supplement or with GDNF:PEI-NPs in the media. The total number of neurons (A, mean ± SEM) decreased in cultures without GDNF supplement, but there were no changes in the number of surviving neurons with incubation of GDNF:PEI-NPs compared to the controls. The same result was found concerning the number of surviving motor neuron (B, mean ± SEM). Corresponding fluorescent anti-pan-neurofilament staining of control culture (C), culture cultivated without GDNF (D) and culture with GDNF:PEI-NPs (E). Bars = 500 μm. Significance differences are marked with * and demonstrate p < 0.05.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4557102&req=5

Figure 4: Analysis of GDNF-functionality of GDNF:PEI-NPs. Cultures were cultivated with GDNF supplemented to the media (100 or 50 ng/ml GDNF) as controls, without any GDNF supplement or with GDNF:PEI-NPs in the media. The total number of neurons (A, mean ± SEM) decreased in cultures without GDNF supplement, but there were no changes in the number of surviving neurons with incubation of GDNF:PEI-NPs compared to the controls. The same result was found concerning the number of surviving motor neuron (B, mean ± SEM). Corresponding fluorescent anti-pan-neurofilament staining of control culture (C), culture cultivated without GDNF (D) and culture with GDNF:PEI-NPs (E). Bars = 500 μm. Significance differences are marked with * and demonstrate p < 0.05.
Mentions: First, we tested for bio-functionality of GDNF:PEI-NPs after coupling. For this, we analyzed the number of surviving motor neurons in organotypic spinal cord cultures incubated with these NPs instead of GDNF supplement via media. GDNF:PEI-NPs were able to keep motor neuronal populations alive. There were no significant differences in the total number of surviving neurons or in the number of motor neurons between controls containing 100 or 50 ng/ml GDNF in the media and GDNF:PEI-NPs incubated cultures (Figures 4A,B). Parallel handled cultures that were cultivated without GDNF supplement displayed significantly less surviving neurons in the total number and in the number of motor neurons than controls 100 (100 ng/ml GDNF supplement). Figures 4C–E show corresponding immunofluorescent stainings for anti-pan-neurofilament. Controls and cultures, incubated with GDNF:PEI-NPs illustrated a prominent motor neuronal population (Figures 4C,E). Cultures without GDNF supplement displayed a clear reduction of stained motor neurons (Figure 4D). Accordingly, GDNF function was kept during coupling to the PEI-NPs.

Bottom Line: Nanoparticles (NPs) show new characteristics compared to the corresponding bulk material.It also shows that successful functionalization of magnetic NPs with growth factors is dependent on the used binding chemistry and that it is hardly predictable.For use as therapeutics, functionalization strategies have to be reproducible and future studies are needed.

View Article: PubMed Central - PubMed

Affiliation: Department of Nephrology and Hypertension, Diabetes and Endocrinology, Otto-von-Guericke University of Magdeburg Magdeburg, Germany ; Institute for Biochemistry and Cell Biology, Otto-von-Guericke University of Magdeburg Magdeburg, Germany.

ABSTRACT
Nanoparticles (NPs) show new characteristics compared to the corresponding bulk material. These nanoscale properties make them interesting for various applications in biomedicine and life sciences. One field of application is the use of magnetic NPs to support regeneration in the nervous system. Drug delivery requires a functionalization of NPs with bio-functional molecules. In our study, we functionalized self-made PEI-coated iron oxide NPs with nerve growth factor (NGF) and glial cell-line derived neurotrophic factor (GDNF). Next, we tested the bio-functionality of NGF in a rat pheochromocytoma cell line (PC12) and the bio-functionality of GDNF in an organotypic spinal cord culture. Covalent binding of NGF to PEI-NPs impaired bio-functionality of NGF, but non-covalent approach differentiated PC12 cells reliably. Non-covalent binding of GDNF showed a satisfying bio-functionality of GDNF:PEI-NPs, but turned out to be unstable in conjugation to the PEI-NPs. Taken together, our study showed the importance of assessing bio-functionality and binding stability of functionalized growth factors using proper biological models. It also shows that successful functionalization of magnetic NPs with growth factors is dependent on the used binding chemistry and that it is hardly predictable. For use as therapeutics, functionalization strategies have to be reproducible and future studies are needed.

No MeSH data available.


Related in: MedlinePlus