title: Smokeless tobacco and nicotine bring about excessive cytokine responses of murine memory T-cells.
abstract: To determine the influence of smokeless tobacco (ST) and nicotine on the cytokine phenotype of memory T-cells, splenic mononuclear cells (SPM) were exposed to 1:10(2) or 1:10(3) dilutions of ST extract (ST-SPM), 10 or 100 microg/ml nicotine (NIC-SPM), or medium (CON-SPM) during 4 days of stimulation with anti-CD3. SPM were then washed extensively to remove residual ST or nicotine and restimulated with anti-CD3 and anti-CD28 in the absence of ST or nicotine. Expression of IL-2, IL-4, IL-10 and IFN-gamma protein and mRNA levels after 4 days of primary stimulation and after 24 and 48 h of restimulation was evaluated using ELISA and RT-PCR, respectively. After 4 days of primary stimulation, SPM exposed to 100 microg/ml nicotine sustained expression of IL-2, IFN-gamma, IL-10 and IL-4 mRNA as opposed to CON-SPM. Restimulation of CON-SPM resulted in maximum re-expression of cytokine mRNA at 24 h and a decline by 48 h. Restimulated NIC-SPM in the absence of nicotine delayed maximal re-expression of IL-2, IFN-gamma, IL-10 and IL-4 mRNA until 48 h. Heightened expression of cytokine mRNA at 48 h was paralleled by a small but significant increase in production of IFN-gamma, IL-4 and IL-10 protein by NIC-SPM as measured by ELISA. In contrast, ST-SPM did not exhibit residual expression of cytokine mRNA after 4 days of primary stimulation. Like NIC-SPM, however, restimulated ST-SPM exhibited maximum IL-2, IL-4, IFN-gamma, and IL-10 mRNA at 48 h. Heightened re-expression of cytokine mRNA at 48 h by ST-SPM was paralleled by increased production of IL-2, IFN-gamma, IL-4 and IL-10 protein. These results indicate that exposure of T-cells to nicotine, but not ST, during a primary immune response result in inordinate cytokine expression after 4 days. In addition, memory T-cells initially exposed to nicotine or ST during a primary immune response, exhibit excessive cytokine expression when T-cells are restimulated in the absence of nicotine or ST. pharmacology.
authors.affiliation: Department of Oral Biology, University of Nebraska Medical Center, Lincoln 68583-0740, USA.
authors.forename: T M
authors.initials: TM
authors.lastname: Petro
authors.forename: S D
authors.initials: SD
authors.lastname: Schwartzbach
authors.forename: S
authors.initials: S
authors.lastname: Zhang
mesh_terms: D000818:Animals; D016207:Cytokines / Q000096:biosynthesis* / Q000235:genetics; D005260:Female; D007156:Immunologic Memory; D051379:Mice; D008807:Mice, Inbred BALB C; D009538:Nicotine / Q000494:pharmacology*; D010947:Plants, Toxic; D012333:RNA, Messenger / Q000032:analysis; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology; D014030:Tobacco, Smokeless
chemical_list: D016207:Cytokines; D012333:RNA, Messenger; D009538:Nicotine