Kits. Results: Subcutaneous injection of yeast produced a marked increase in rectal temperature of rats with a maximum effect at 6 hours (101.17 ). Like paracetamol, treatment of rats with AqDL and MeDL produced a significant decrease in body temperature from 101.17 at 6 hours to 97.9 and 98.2 at 9 hours respectively at higher doses and their effect was dose dependent while LP was found to be ineffective. The present study shows that treatment with yeast increased the tissue levels of TNFa (23.78 pg/mg) and PGE 2 (66.48 pg/mg) as compared with the NC group (16.31 and 41.35 respectively). All of the fractions lowered the hypothalamic TNFa level while a marked reduction in PGE 2 levels was observed with orally effective fractions, namely AqDL and MeDL. Conclusion: Our results demonstrate that the orally administered fractions of latex of C. procera are effective in attenuating yeast-induced pyrexia and this effect is mediated through reduction in the levels of PGE2. P46 Regulation of sepsis-induced IFNg upon natural killer cell or natural killer T cell depletion in vivo E Christaki1*, E Diza1, EJ Giamarellos-Bourboulis2, N Papadopoulou3, A Pistiki2, D Droggiti2, A Machova3, M Georgitsi2, D Lambrelli4, G Karkavelas1, A Iliadis1, N Malisiovas1, P Nikolaidis1, SM Opal5 1 Aristotle University of Thessaloniki Medical School, Thessaloniki, Greece; 2 University of Athens Medical School, Athens, Greece; 3University of Cologne,ZM241385 biological activity Background: Natural killer (NK) and natural killer T (NKT) cells play a key role in bacterial infection and sepsis since they contribute to the bridging of innate and acquired immune responses. We have previously shown that in vivo depletion of these cell populations in a murine pneumococcal pneumonia sepsis model affected mortality. Methods: Four groups of C57BL/6 mice (n = 5 to 15 mice/group) were infected intratracheally with 5 ?10 5 CFU Streptococcus pneumoniae. Twenty-four hours prior to bacterial inoculation, NK cell depletion was achieved by intravenous (i.v.) administration of anti-asialoGM1 rabbit polyclonal antibody in one group (NK DEPL ), or anti-CD1d monoclonal antibody, clone 1B1 was given for NKT cell depletion in a second group (NKTDEPL). The control group received equal volume of isotype antibody control i.v. (C) and a fourth group received sham intratracheal installation of normal saline (S). All animals were euthanized 48 hours post infection. Serum and tissue samples were analyzed for bacterial colony counts, cytokine levels, splenocyte apoptosis rates and cell population analysis by flow cytometry. In parallel, specific miRNA expression analyses in splenocytes and lung histologic examination were also performed. Comparisons of numeric data between groups were made using the oneway ANOVA test for multiple groups. Results: We found that upon NK cell depletion there was a PubMed ID:https://www.ncbi.nlm.nih.gov/pubmed/26100631 significant increase in the spleen NKT (CD3+/CD1d+) cell population compared with NKT DEPL , C and S (P = 0.014, P = 0.021 and P = 0.033, respectively). Interestingly, upon NKT cell depletion, spleen NK (CD3 – /NK1.1 + ) cells increased significantly compared with NKDEPL, C and S (P < 0.0001, P < 0.0001 and P = 0.001, respectively). NKT depletion led to decreased lymphocyte apoptosis compared with C (P = 0.035), higher bacterial load in the lung compared with C and NK DEPL (P = 0.014 and P = 0.022 respectively) and in the liver compared with C (P = 0.012). In addition, serum levels of IFNg were significantly increased and splenocytes fr.