Biomedical Engineering Reference
In-Depth Information
TABLE 20.1
Immunotoxicity of Carbon-Based Nanomaterials
Sl. No.
Carbon Nanoparticle
Summary
1
Induction of MCP-1, CCL2, IL-6, C-reactive protein, and
exaggeration of atherosclerosis in animals
Carbon black (<100 nm)
2
Carbon black (14 nm)
Induction of slight expression of CD80 and MHC class II
and significant expression of CD86 and DEC205 in
endothelial cells
3
Single-walled carbon nanotubes (PEG coating
1-5 nm in diameter, 50-200 nm in length)
Persistence of SWNT for several months in kidney and liver
without obvious toxicity
4
Single-walled carbon nanotubes
(1-4 nm in diameter)
Biodegradation of single-walled carbon nanotubes by
hypochlorite and ROS mediated by human neutrophil
myeloperoxidase
5
Single-walled carbon nanotubes (1-2 nm in
diameter, 20 nm to several μm in length)
Induction of ROS, inflammatory cytokines, and expression of
apoptosis-related genes in macrophages
6
Single-walled carbon nanotubes
(800 nm length)
Inhibition of production of IL-8, 6, TNF-α, and MCP-1 in
A549 cells
7
Multiwalled carbon nanotubes
(10-30 nm in diameter, 30-50 nm in length)
Induction of fibrosis in asthma animal model and suggestion
of the role of TGF-β and PDGF
8
Multiwalled carbon nanotubes
(20-40 nm in diameter, 5-30 μm in length)
Induction of ROS, inflammatory cytokines, and activation of
NF-κB, in A549 or BEAS-2B cells
9
C60 fullerene (0.7 nm in diameter)
No toxicity in animal lung
Source:
From Jang J, Lim D-H and Choi I-H.
Immune Network
2010;10(3):85-91. With permission.
Contamination is one of the reasons for CNTs' potential damage. The presence of such impurities
interferes with experiments conducted on the inherent toxicity of CNTs. Transition metals are par-
ticularly effective as catalysts of oxidative stress in cells, tissues, and biofluids. In a particular study
[23], interactions of two types of SWCNT (1) iron-rich (nonpurified) SWCNT (26% of iron) and (2)
iron-stripped (purified) SWCNT (0.23 wt% of iron) with RAW264.7 macrophages was studied. Each
type of SWCNT was able to generate intracellular production of superoxide radicals or nitric oxide
in the cells. Less pure iron-rich SWCNT were more effective in generating hydroxyl radicals, and
superoxide radicals, accumulating lipid hydroperoxides, and causing significant loss of intracellular
low-molecular-weight thiols (GSH). Therefore, the inflammatory responses caused by nanotubes with
metals can be particularly damaging. Oxidative species generated during inflammatory response can
interact with transition metals to trigger redox-cycling cascades with a remarkable oxidizing potential
to deplete endogenous reserves of antioxidants and induce oxidative damage to macromolecules.
Chemical modifications of NP surface have the potential to confer improved biocompatibility of
CNPs. A nanocombinatorial chemistry approach was used to generate an MWCNT library contain-
ing 80 different surface modifications [24]. In addition to the successful regulation of protein bind-
ing and cytotoxicity, they also showed different roles in activating immune systems as measured by
nitric oxide generation. Compared with the precursor, MWCNT-COOH, many modified MWCNTs
exhibited lower immune responses. More biocompatible and immune-friendly nanomedicine carri-
ers can be developed through iterative screening and optimization studies (Table 20.1).
20.12 EFFECTS OF NANOPARTICLE-ADSORBED PROTEINS (PEPTIDES)
ON IMMUNE RESPONSE
The biological fate and (re)biodistribution of NPs strongly depend on the physicochemical charac-
teristics of the particles and the proteins that NPs encounter in the body, particularly in the plasma.
