Abstract 19531: Effect of Mainstream Cigarette Smoke and Its Constituents on Immune Cells
Smoking induces/exacerbates cardiopulmonary diseases possibly via impaired immune function. Yet, little is known about what constituent(s) of mainstream cigarette smoke (MCS) affects immune function. We examined the effects of MCS and acrolein - a reactive aldehyde abundant in tobacco smoke - on the abundance of circulating immune cells. Acute MCS exposure (1 day, 6h) of female and male C57BL/6 mice decreased the abundance of white bloods cells (WBC; lymphocytes, neutrophils and monocytes) by 30-70 %. Similarly, acute exposure to nicotine free cigarette smoke (NFMCS; 1 day, 6h) decreased the levels of lymphocytes and monocytes by 25-50 % in both female and male mice. NFMCS also decreased the levels of neutrophils in female mice by 25%, but did not affect neutrophil abundance in male mice. Flow cytometry analyses of leukocytes showed that MCS decreased NK cells, B-cells, CD4+-T-cells and CD8+-T-cells by 30-70% in both female and male mice. Acute exposure to NFMCS decreased the levels of leukocytes and B-cells by 33-44% only in female mice. Acute exposure to NFMCS had no effect on the levels of NK-cells, CD4+-T-cells and CD8+-T-cells in both female and male mice. Chronic exposure to MCS (6h/day, 7days/week for 12 weeks) decreased the levels of WBC, neutrophils, lymphocytes, NK-cells, B-cells, CD4+-T-cells and CD8+-T-cells, and monocytes by 30-55 % in female mice, whereas levels of these cells were unaffected by chronic exposure to MCS in male mice. However, chronic exposure to acrolein (1.0 ppm, 5 days/week for 12 weeks) also decreased leukocytes, neutrophils, and lymphocytes by 40-70%. Moreover, chronic exposure to acrolein (0.5 or 1.0 ppm) also decreased the levels of B-cells and monocytes by 50-60%. Examination of the sub-population of monocytes showed that MCS, NFMCS and acrolein decreased the levels of activated monocytes (Ly6C+) by 30-70%. These data suggest that: a) acute exposure to MCS significantly suppresses immune cells in both female and male mice whereas chronic exposure to MCS decreases immune cells only in female mice; and b) the immune suppressive effects of MCS, at least in parts, can be attributed to acrolein.
Author Disclosures: M.V. Malovichko: None. S.D. Sithu: None. I. Zeller: None. A. Agarwal: None. T.E. O’Toole: None. A. Bhatnagar: None. D.J. Conklin: None. S. Srivastava: None.
- © 2016 by American Heart Association, Inc.