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Effects of chronic alcohol consumption on natural killer cellmaturation and traffickingHui Zhang and Gary G. Meadows, Cancer Prevention & Research Center,College of Pharmacy, Washington State University, Pullman, WA 99164-6713.

Chronic high alcohol intake decreases the cytolytic activity of natural killer(NK) cells in the spleen and peripheral blood of mice. This reduced cyto-lytic activity is related to 1) decreased expression in perforin and gran-zymes and 2) decreased numbers of splenic NK cells. The mechanismassociated with the decrease in NK cell numbers in the spleen has not beenpreviously studied. Female C57BL/6 mice were allowed free access tostandard laboratory chow and 20% w/v alcohol in their drinking waterfor 2 to 6 months. Differentiation and maturation markers on NK cellsfrom the spleen, bone marrow, peripheral blood, and liver were then exam-ined by flow cytometry. Chronic alcohol consumption reduced the percent-age and numbers of mature NK cells in the peripheral blood, spleen andliver, but not the bone marrow. Both immature and mature NK cells weresignificantly increased in the bone marrow. This suggests that chronic al-cohol consumption does not compromise NK cell development and matu-ration in the bone marrow, but abnormally alters NK cell distribution inbone marrow and peripheral organs. Chronic alcohol consumption alsostimulated homeostatic proliferation of NK cells in the spleen and in-creased apoptosis of NK cells exhibiting an immature phenotype, implicat-ing a developmental blockage of NK cell development at the cellexpansion stage in the spleen. Chronic alcohol consumption did not alterthe expression of cell adhesion molecules on bone marrow or on splenicNK cells. However, the accumulation of NK cells at the peritoneal siteof poly I:C injection was retarded in alcohol consuming mice as comparedto water drinking mice. The expression of certain steady state chemokinesand also chemokines in response to poly I:C infection in the bone marrow,spleen, and liver also was altered by chronic alcohol consumption. Theseresults suggest that chronic alcohol consumption impairs NK cells traffick-ing in response to an inflammatory stimulus. (This work was supported byNIH grant R21AA014200).

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Activation of STAT3-p27Kip1 pathway and impairment of thegranulopoietic response to lung infection in mice with alcoholintoxicationP. Zhang, Q. Zhong, G. J. Bagby and S. Nelson, Alcohol and Drug AbuseCenter and the Departments of Medicine and Physiology, LSUHSC, NewOrleans, LA 70112, USA.

During bacterial infection, granulopoiesis is enhanced in order to supportthe host defense response to invading pathogens. Impairment of this gran-ulopoietic response may result in severe infection and death. Studies haveshown that a significant number of alcohol-abusing patients with infection,particularly pneumonia, present with granulocytopenia. At the presenttime, the underlying mechanisms remain poorly understood. The infectedlung produces granulocyte colony-stimulating factor (G-CSF), a potent cy-tokine that stimulates myeloid progenitor cell proliferation and granulocyteproduction. In addition to its role in promoting granulocyte production,G-CSF also activates STAT3 which serves as a negative feedback signal tomyeloid progenitor proliferation. Phospho-STAT3 activates the transcrip-tion of cyclin-dependent kinase inhibitor p27Kip1 causing G1 arrest in my-eloid progenitor cells. This study investigated the effects of alcohol on theactivation of the STAT3-p27Kip1 pathway in bone marrow and myeloid pro-genitor cells following lung infection and G-CSF stimulation. Acute alco-hol intoxication was induced in chronic alcohol consuming mice fed withthe Lieber-DeCarli low fat liquid alcohol diet for 5 weeks by an i.p. injec-tion of alcohol (20% alcohol in saline, 5 g alcohol/kg). Thirty min later,S. pneumoniae (type 3, | 1 x 105 cfu/mouse) or G-CSF (200 mg/kg) wasadministered via an intratracheal injection. Animals were sacrificed at10 h after the pneumococcal challenge or 30 min post G-CSF. Alcohol in-toxication enhanced STAT3 phosphorylation in bone marrow cells follow-ing lung challenge with either S. pneumoniae or G-CSF. In vitro exposureto alcohol also enhanced G-CSF-stimulated STAT3 phosphorylationin bone marrow cells. Alcohol caused a dose-dependent inhibition ofG-CSF-stimulated murine myeloid progenitor cell line (32D-G-CSFR) cellproliferation, while STAT3 phosphorylation and p27Kip1 expression wereenhanced in these cells following alcohol exposure. These data show thatthe STAT3- p27Kip1 pathway is involved in alcohol-induced suppression ofthe granulopoietic response to lung infection. (Supported by NIH grantAA09803).

117Abstracts / Alcohol 39 (2006) 111e117