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Cutaneous exposure to agglomerates of silica nanoparticles and allergen results in IgE-biased immune response and increased sensitivity to anaphylaxis in mice.

Hirai T, Yoshioka Y, Takahashi H, Ichihashi K, Udaka A, Mori T, Nishijima N, Yoshida T, Nagano K, Kamada H, Tsunoda S, Takagi T, Ishii KJ, Nabeshi H, Yoshikawa T, Higashisaka K, Tsutsumi Y - Part Fibre Toxicol (2015)

Bottom Line: Our data suggest that silica nanoparticles themselves do not directly affect the allergen-specific immune response after concurrent topical application of nanoparticles and allergen.However, when present in allergen-adsorbed agglomerates, silica nanoparticles led to a low IgG/IgE ratio, a key risk factor of human atopic allergies.We suggest that minimizing interactions between nanomaterials and allergens will increase the safety of nanomaterials applied to skin.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Toxicology and Safety Science, Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka, 565-0871, Japan. t-hirai@phs.osaka-u.ac.jp.

ABSTRACT

Background: The skin is a key route of human exposure to nanomaterials, which typically occurs simultaneously with exposure to other chemical and environmental allergen. However, little is known about the hazards of nanomaterial exposure via the skin, particularly when accompanied by exposure to other substances.

Results: Repeated topical treatment of both ears and the shaved upper back of NC/Nga mice, which are models for human atopic dermatitis (AD), with a mixture of mite extract and silica nanoparticles induced AD-like skin lesions. Measurements of ear thickness and histologic analyses revealed that cutaneous exposure to silica nanoparticles did not aggravate AD-like skin lesions. Instead, concurrent cutaneous exposure to mite allergens and silica nanoparticles resulted in the low-level production of allergen-specific IgGs, including both the Th2-related IgG1 and Th1-related IgG2a subtypes, with few changes in allergen-specific IgE concentrations and in Th1 and Th2 immune responses. In addition, these changes in immune responses increased the sensitivity to anaphylaxis. Low-level IgG production was induced when the mice were exposed to allergen-silica nanoparticle agglomerates but not when the mice exposed to nanoparticles applied separately from the allergen or to well-dispersed nanoparticles.

Conclusions: Our data suggest that silica nanoparticles themselves do not directly affect the allergen-specific immune response after concurrent topical application of nanoparticles and allergen. However, when present in allergen-adsorbed agglomerates, silica nanoparticles led to a low IgG/IgE ratio, a key risk factor of human atopic allergies. We suggest that minimizing interactions between nanomaterials and allergens will increase the safety of nanomaterials applied to skin.

No MeSH data available.


Related in: MedlinePlus

Physicochemical properties of silica nanoparticles alone and combined with allergen. a Macroscopic and (b) transmission electomicrographic images of the samples used in this study (scale bar, 100 nm). c Particle size distributions of samples diluted in PBS or water measured by using a dynamic light scattering method. d Mean particle diameters and zeta potentials of samples
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Fig1: Physicochemical properties of silica nanoparticles alone and combined with allergen. a Macroscopic and (b) transmission electomicrographic images of the samples used in this study (scale bar, 100 nm). c Particle size distributions of samples diluted in PBS or water measured by using a dynamic light scattering method. d Mean particle diameters and zeta potentials of samples

Mentions: For these experiments, we used silica nanoparticles with a diameter of 30 nm (nSP30). Solutions of nSP30 were clear and colorless (Fig. 1a), and transmission electron microscopy (TEM) revealed that the particles were smooth spheres (Fig. 1b). The size distribution spectrum of nSP30 was a single peak (Fig. 1c), and the mean hydrodynamic diameter (24.1 nm, as measured by means of a dynamic light-scattering method; Fig. 1d) corresponded almost exactly to the primary particle size. These results indicate that the nSP30 particles were well dispersed in solution.Fig. 1


Cutaneous exposure to agglomerates of silica nanoparticles and allergen results in IgE-biased immune response and increased sensitivity to anaphylaxis in mice.

Hirai T, Yoshioka Y, Takahashi H, Ichihashi K, Udaka A, Mori T, Nishijima N, Yoshida T, Nagano K, Kamada H, Tsunoda S, Takagi T, Ishii KJ, Nabeshi H, Yoshikawa T, Higashisaka K, Tsutsumi Y - Part Fibre Toxicol (2015)

Physicochemical properties of silica nanoparticles alone and combined with allergen. a Macroscopic and (b) transmission electomicrographic images of the samples used in this study (scale bar, 100 nm). c Particle size distributions of samples diluted in PBS or water measured by using a dynamic light scattering method. d Mean particle diameters and zeta potentials of samples
© Copyright Policy - open-access
Related In: Results  -  Collection

License 1 - License 2
Show All Figures
getmorefigures.php?uid=PMC4482284&req=5

Fig1: Physicochemical properties of silica nanoparticles alone and combined with allergen. a Macroscopic and (b) transmission electomicrographic images of the samples used in this study (scale bar, 100 nm). c Particle size distributions of samples diluted in PBS or water measured by using a dynamic light scattering method. d Mean particle diameters and zeta potentials of samples
Mentions: For these experiments, we used silica nanoparticles with a diameter of 30 nm (nSP30). Solutions of nSP30 were clear and colorless (Fig. 1a), and transmission electron microscopy (TEM) revealed that the particles were smooth spheres (Fig. 1b). The size distribution spectrum of nSP30 was a single peak (Fig. 1c), and the mean hydrodynamic diameter (24.1 nm, as measured by means of a dynamic light-scattering method; Fig. 1d) corresponded almost exactly to the primary particle size. These results indicate that the nSP30 particles were well dispersed in solution.Fig. 1

Bottom Line: Our data suggest that silica nanoparticles themselves do not directly affect the allergen-specific immune response after concurrent topical application of nanoparticles and allergen.However, when present in allergen-adsorbed agglomerates, silica nanoparticles led to a low IgG/IgE ratio, a key risk factor of human atopic allergies.We suggest that minimizing interactions between nanomaterials and allergens will increase the safety of nanomaterials applied to skin.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of Toxicology and Safety Science, Graduate School of Pharmaceutical Sciences, Osaka University, 1-6 Yamadaoka, Suita, Osaka, 565-0871, Japan. t-hirai@phs.osaka-u.ac.jp.

ABSTRACT

Background: The skin is a key route of human exposure to nanomaterials, which typically occurs simultaneously with exposure to other chemical and environmental allergen. However, little is known about the hazards of nanomaterial exposure via the skin, particularly when accompanied by exposure to other substances.

Results: Repeated topical treatment of both ears and the shaved upper back of NC/Nga mice, which are models for human atopic dermatitis (AD), with a mixture of mite extract and silica nanoparticles induced AD-like skin lesions. Measurements of ear thickness and histologic analyses revealed that cutaneous exposure to silica nanoparticles did not aggravate AD-like skin lesions. Instead, concurrent cutaneous exposure to mite allergens and silica nanoparticles resulted in the low-level production of allergen-specific IgGs, including both the Th2-related IgG1 and Th1-related IgG2a subtypes, with few changes in allergen-specific IgE concentrations and in Th1 and Th2 immune responses. In addition, these changes in immune responses increased the sensitivity to anaphylaxis. Low-level IgG production was induced when the mice were exposed to allergen-silica nanoparticle agglomerates but not when the mice exposed to nanoparticles applied separately from the allergen or to well-dispersed nanoparticles.

Conclusions: Our data suggest that silica nanoparticles themselves do not directly affect the allergen-specific immune response after concurrent topical application of nanoparticles and allergen. However, when present in allergen-adsorbed agglomerates, silica nanoparticles led to a low IgG/IgE ratio, a key risk factor of human atopic allergies. We suggest that minimizing interactions between nanomaterials and allergens will increase the safety of nanomaterials applied to skin.

No MeSH data available.


Related in: MedlinePlus