title: Dispersal state of multiwalled carbon nanotubes elicits profibrogenic cellular responses that correlate with fibrogenesis biomarkers and fibrosis in the murine lung.
abstract: We developed a dispersal method for multiwalled carbon nanotubes (MWCNTs) that allows quantitative assessment of dispersion on profibrogenic responses in tissue culture cells and in mouse lung. We demonstrate that the dispersal of as-prepared (AP), purified (PD), and carboxylated (COOH) MWCNTs by bovine serum albumin (BSA) and dipalmitoylphosphatidylcholine (DPPC) influences TGF-β1, PDGF-AA, and IL-1β production in vitro and in vivo. These biomarkers were chosen based on their synergy in promoting fibrogenesis and cellular communication in the epithelial-mesenchymal cell trophic unit in the lung. The effect of dispersal was most noticeable in AP- and PD-MWCNTs, which are more hydrophobic and unstable in aqueous buffers than hydrophilic COOH-MWCNTs. Well-dispersed AP- and PD-MWCNTs were readily taken up by BEAS-2B, THP-1 cells, and alveolar macrophages (AM) and induced more prominent TGF-β1 and IL-1β production in vitro and TGF-β1, IL-1β, and PDGF-AA production in vivo than nondispersed tubes. Moreover, there was good agreement between the profibrogenic responses in vitro and in vivo as well as the ability of dispersed tubes to generate granulomatous inflammation and fibrosis in airways. Tube dispersal also elicited more robust IL-1β production in THP-1 cells. While COOH-MWCNTs were poorly taken up in BEAS-2B and induced little TGF-β1 production, they were bioprocessed by AM and induced less prominent collagen deposition at sites of nongranulomatous inflammation in the alveolar region. Taken together, these results indicate that the dispersal state of MWCNTs affects profibrogenic cellular responses that correlate with the extent of pulmonary fibrosis and are of potential use to predict pulmonary toxicity.
authors: Division of NanoMedicine, Department of Medicine, University of California, Los Angeles, California 90095, United States.
authors: Xiang
authors: X
authors: Wang
authors: Tian
authors: T
authors: Xia
authors: Susana Addo
authors: SA
authors: Ntim
authors: Zhaoxia
authors: Z
authors: Ji
authors: Sijie
authors: S
authors: Lin
authors: Huan
authors: H
authors: Meng
authors: Choong-Heui
authors: CH
authors: Chung
authors: Saji
authors: S
authors: George
authors: Haiyuan
authors: H
authors: Zhang
authors: Meiying
authors: M
authors: Wang
authors: Ning
authors: N
authors: Li
authors: Yang
authors: Y
authors: Yang
authors: Vincent
authors: V
authors: Castranova
authors: Somenath
authors: S
authors: Mitra
authors: James C
authors: JC
authors: Bonner
authors: André E
authors: AE
authors: Nel
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D016207:Cytokines / Q000378:metabolism*; D004305:Dose-Response Relationship, Drug; D008168:Lung / Q000187:drug effects / Q000378:metabolism*; D051379:Mice; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000633:toxicity*; D011658:Pulmonary Fibrosis / Q000139:chemically induced* / Q000378:metabolism*; D014018:Tissue Distribution
chemical_list: D015415:Biomarkers; D016207:Cytokines; D037742:Nanotubes, Carbon