Single-walled carbon nanotubes impair human macrophage engulfment of apoptotic cell corpses.
Single-walled carbon nanotubes (SWCNT) are being produced in increasing quantities and the application of these materials in a large number of new technologies and consumer products necessitates studies of their potential impact on human health and the environment. To determine whether SWCNT affect viability or function of macrophages, important components of the innate immune system, we performed in vitro studies using primary human monocyte-derived macrophages (HMDM). Our findings show that SWCNT with a low content of metal impurities do not exert direct cytotoxic effects on HMDM. However, SWCNT suppressed chemotaxis of primary human monocytes in a standard chemotaxis assay. Moreover, macrophage engulfment of apoptotic target cells was significantly impaired following pre-incubation of HMDM with SWCNT at non-cytotoxic concentrations. These results are in line with previous studies showing that ultrafine carbon particles and carbon nanotubes may impair alveolar macrophage ingestion of microorganisms, and suggest that tissue homeostasis may be compromised by SWCNT due to suppressive effects on macrophages.
Witasp
Erika
E
Division of Biochemical Toxicology, Institute of Environmental Medicine, Karolinska Institutet, Stockholm, Sweden.
Shvedova
Anna A
AA
Kagan
Valerian E
VE
Fadeel
Bengt
B
D017209:Apoptosis; D002470:Cell Survival / Q000187:drug effects; D002633:Chemotaxis / Q000187:drug effects; D006801:Humans; D007113:Immunity, Innate / Q000187:drug effects*; D019169:Jurkat Cells; D008264:Macrophages / Q000187:drug effects* / Q000276:immunology; D037742:Nanotubes, Carbon / Q000633:toxicity*; D052638:Particulate Matter / Q000633:toxicity*; D010587:Phagocytosis / Q000187:drug effects*; D013997:Time Factors
D037742:Nanotubes, Carbon; D052638:Particulate Matter