Heterogeneities in inflammatory and cytotoxic responses of RAW 264.7 macrophage cell line to urban air coarse, fine, and ultrafine particles from six European sampling campaigns.
We investigated the cytotoxic and inflammatory activities of size-segregated particulate samples (particulate matter, PM) from contrasting air pollution situations in Europe. Coarse (PM10-2.5), fine (PM2.5-0.2), and ultrafine (PM0.2) particulate samples were collected with a modified Harvard high-volume cascade impactor (HVCI). Mouse RAW 264.7 macrophages were exposed to the samples for 24 h. Selected inflammatory mediators, nitric oxide (NO) and cytokines (tumor necrosis factor alpha [TNFalpha], interleukin 6 [IL-6], macrophage inflammatory protein-2 [MIP-2]), were measured together with cytotoxicity (MTT test), and analysis of apoptosis and cell cycle (propidium iodide staining). The PM10-2.5 samples had a much higher inflammatory activity than the PM2.5-0.2 and PM0.2 samples, but the PM2.5-0.2 samples showed the largest differences in inflammatory activity, and the PM0.2 samples in cytotoxicity, between the sampling campaigns. The PM2.5-0.2 samples from traffic environments in springtime Barcelona and summertime Athens had the highest inflammatory activities, which may be related to the high photochemical activity in the atmosphere during the sampling campaigns. The PM0.2 sample from wintertime Prague with proven impacts from local coal and biomass combustion had very high cytotoxic and apoptotic activities and caused a distinct cell cycle arrest. Thus, particulate size, sources, and atmospheric transformation processes affect the toxicity profile of urban air particulate matter. These factors may explain some of the heterogeneity observed in particulate exposure-response relationships of human health effects in epidemiological studies.
Jalava
Pasi I
PI
National Public Health Institute, Department of Environmental Health, Kuopio, Finland. Pasi.Jalava@ktl.fi
Salonen
Raimo O
RO
Pennanen
Arto S
AS
Sillanpää
Markus
M
Hälinen
Arja I
AI
Happo
Mikko S
MS
Hillamo
Risto
R
Brunekreef
Bert
B
Katsouyanni
Klea
K
Sunyer
Jordi
J
Hirvonen
Maija-Riitta
MR
D000393:Air Pollutants / Q000633:toxicity*; D000818:Animals; D002460:Cell Line; D002470:Cell Survival / Q000187:drug effects; D016207:Cytokines / Q000096:biosynthesis; D007249:Inflammation / Q000139:chemically induced*; D008264:Macrophages / Q000187:drug effects*; D051379:Mice; D009569:Nitric Oxide / Q000096:biosynthesis; D010316:Particle Size; D052638:Particulate Matter / Q000633:toxicity*
D000393:Air Pollutants; D016207:Cytokines; D052638:Particulate Matter; D009569:Nitric Oxide