TY - JOUR
T1 - Toxicity of lunar and Martian dust simulants to alveolar macrophages isolated from human volunteers
AU - Latch, Judith N.
AU - Hamilton, Raymond F.
AU - Holian, Andrij
AU - James, John T.
AU - Lam, Chiu Wing
N1 - Funding Information:
ing the fine dust samples from these raw materials. Furthermore, the Received 16 August 2007; accepted 25 September 2007. authors thank Dr. Jane Krauhs of Wyle for her assistance with technical Current address for Judith N. Latch is Johnson Space Center Tox-writing and Dr. Tatyana Gots of the University of Texas Health Sci-icology Group and Wyle, SF-23, Houston, TX 77058, USA. Current ence Center, Houston (TX) for her technical assistance. This work was address for Richard Hamilton and Andrij Holian is 280B Skaggs Build-supported by NASA’s Graduate Student Researchers Program grant ing, Center for Environmental Health Sciences, Department of Pharma-NGT5-50084 (JNL) and by NIH Clinical Research Center grant M01-ceutical Sciences, University of Montana, Missoula, MT 59812, USA. RR-02558 (AH).
PY - 2008/1
Y1 - 2008/1
N2 - NASA is planning to build a habitat on the Moon and use the Moon as a stepping stone to Mars. JSC-1, an Arizona volcanic ash that has mineral properties similar to those of lunar soil, is used to produce lunar environments for instrument and equipment testing. NASA is concerned about potential health risks to workers exposed to these fine dusts in test facilities. The potential toxicity of JSC-1 lunar soil simulant and a Martian soil simulant (JSC-Mars-1, a Hawaiian volcanic ash) was evaluated using human alveolar macrophages (HAM) isolated from volunteers; titanium dioxide and quartz were used as reference dusts. This investigation is a prerequisite to studies of actual lunar dust. HAM were treated in vitro with these test dusts for 24 h; assays of cell viability and apoptosis showed that JSC-1 and TiO2 were comparable, and more toxic than saline control but less toxic than quartz. HAM treated with JSC-1 or JSC-Mars 1 showed a dose-dependent increase in cytotoxicity. To elucidate the mechanism by which these dusts induce apoptosis, we investigated the involvement of scavenger receptors (SR). Pretreatment of cells with polyinosinic acid, an SR blocker, significantly inhibited both apoptosis and necrosis. These results suggest HAM cytotoxicity may be initiated by interaction of the dust particles with SR. Besides being cytotoxic, silica is known to induce shifting of HAM phenotypes to an immune active status. The immunomodulatory effect of the dust simulants was investigated. Treatment of HAM with either simulant caused preferential damage to the suppressor macrophage subpopulation, leading to a net increase in the ratio of activator (RFD1+) to suppressor (RFD1+7+) macrophages, an effect similar to that of treatment with silica. It is recommended that appropriate precautions be used to minimize exposure to these fine dusts in large-scale engineering applications.
AB - NASA is planning to build a habitat on the Moon and use the Moon as a stepping stone to Mars. JSC-1, an Arizona volcanic ash that has mineral properties similar to those of lunar soil, is used to produce lunar environments for instrument and equipment testing. NASA is concerned about potential health risks to workers exposed to these fine dusts in test facilities. The potential toxicity of JSC-1 lunar soil simulant and a Martian soil simulant (JSC-Mars-1, a Hawaiian volcanic ash) was evaluated using human alveolar macrophages (HAM) isolated from volunteers; titanium dioxide and quartz were used as reference dusts. This investigation is a prerequisite to studies of actual lunar dust. HAM were treated in vitro with these test dusts for 24 h; assays of cell viability and apoptosis showed that JSC-1 and TiO2 were comparable, and more toxic than saline control but less toxic than quartz. HAM treated with JSC-1 or JSC-Mars 1 showed a dose-dependent increase in cytotoxicity. To elucidate the mechanism by which these dusts induce apoptosis, we investigated the involvement of scavenger receptors (SR). Pretreatment of cells with polyinosinic acid, an SR blocker, significantly inhibited both apoptosis and necrosis. These results suggest HAM cytotoxicity may be initiated by interaction of the dust particles with SR. Besides being cytotoxic, silica is known to induce shifting of HAM phenotypes to an immune active status. The immunomodulatory effect of the dust simulants was investigated. Treatment of HAM with either simulant caused preferential damage to the suppressor macrophage subpopulation, leading to a net increase in the ratio of activator (RFD1+) to suppressor (RFD1+7+) macrophages, an effect similar to that of treatment with silica. It is recommended that appropriate precautions be used to minimize exposure to these fine dusts in large-scale engineering applications.
UR - http://www.scopus.com/inward/record.url?scp=38849126103&partnerID=8YFLogxK
U2 - 10.1080/08958370701821219
DO - 10.1080/08958370701821219
M3 - Article
C2 - 18236230
AN - SCOPUS:38849126103
SN - 0895-8378
VL - 20
SP - 157
EP - 165
JO - Inhalation Toxicology
JF - Inhalation Toxicology
IS - 2
ER -