Background Glucocorticoid resistance has been associated with Th17-driven inflammation, the mechanisms of which are not clear. We determined whether human and mouse Th17 cells are resistant to glucocorticoid-induced apoptosis. Methods Freshly isolated human blood Th17 cells and in vitro differentiated Th17 cells from IL-17F red fluorescent protein reporter mice were treated with dexamethasone, a potent glucocorticoid. Apoptosis was measured using annexin V and DAPI staining. Screening of apoptosis genes was performed using the apoptosis PCR array. Levels of molecules involved in apoptosis were measured using quantitative RT-PCR, flow cytometry, and Western blotting. Knockdown of BCL-2 in murine Th17 cells was performed via retroviral transduction. Cytokines were measured using ELISA. A murine Th17-driven severe asthma model was examined for Th17 glucocorticoid sensitivity in vivo. Results Human and mouse Th17 cells and mouse Th2 cells were resistant to glucocorticoid-induced apoptosis. Th17 cells had glucocorticoid receptors levels comparable to those in other T effectors cells. Th17 cells had high levels of BCL-2, knockdown of which sensitized Th17 cells to dexamethasone-induced apoptosis. Production of IL-22, but not IL-17A and IL-17F, was suppressed by glucocorticoids. STAT3 phosphorylation in Th17 cells was insensitive to glucocorticoid inhibition. Lung Th17 cells in the murine severe asthma model were enhanced, rather than suppressed, by glucocorticoids. Conclusion Th17 cells are resistant to glucocorticoid-induced apoptosis and cytokine suppression, at least in part due to high levels of BCL-2. These findings support a role of Th17 cells in glucocorticoid-resistant inflammatory conditions such as certain endotypes of asthma.

Dose-surface histograms are studied and compared with dose-volume histograms, as an evaluation tool for prostate treatment planning. For thin walled hollow organs, such as the rectum and bladder, the surface area irradiated is a more appropriate measure of the biological effect than the full volume. It is also more accurate and efficient to define the surface for a hollow structure and compute the surface area histograms. Application of the dose-surface histograms provide new insights into prostate treatment planning. A simple idealized geometry model demonstrates that the percentage surface area intersected by the geometric beam edge differs from the percentage volume intersected. For a group of prostate patients, it is shown that the dose-surface histograms yield substantially different results from the dose-volume histograms in ranking four-, six-, and, eight-field treatment plans and in calculating the fraction of the rectum irradiated to high dose. The difference in terms of surface area between these plans in the high-dose region is usually less than that in terms of the volume, and a reverse of plan ranking order can consequently occur. The percentage of organ surface irradiated to high dose is typically greater than the percentage volume by 5% to 10%. The use of the dose-surface histograms in analysis of organ motion and/or patient setup uncertainty, and analysis of rectal complications, is also discussed.

A measurement of the absolute fluorescence yield of the 337 nm nitrogen band, relevant to ultra-high energy cosmic ray (UHECR) detectors, is reported. Two independent calibrations of the fluorescence emission induced by a 120 GeV proton beam were employed: Cherenkov light from the beam particle and calibrated light from a nitrogen laser. The fluorescence yield in air at a pressure of 1013 hPa and temperature of 293 K was found to be Y 337 = 5.61±0.06 stat ±0.21 syst photons/MeV. When compared to the fluorescence yield currently used by UHECR experiments, this measurement improves the uncertainty by a factor of three, and has a significant impact on the determination of the energy scale of the cosmic ray spectrum.Key words: Nitrogen Fluorescence Yield, Air Fluorescence Detection, Ultra-High Energy Cosmic Rays PACS: , 96.50. 96.50.sb, 96.50.sd, 32.50.+d, 34.50.Fa, 34.50.Gb IntroductionA well established technique for the detection of Ultra-High Energy ( 10 18 eV) Cosmic Rays (UHECRs) -first successfully employed by the Fly's Eye [1] and HiRes [2] experiments -is based on nitrogen fluorescence light emission induced by Extensive Air Showers (EAS). Excitation of atmospheric nitrogen by EAS charged particles results in fluorescence emission, mostly in the wavelength range between 300 and 430 nm. This UV light is measured as a function of time and incoming direction by photomultiplier cameras at the focus of large (few m 2 ) mirrors. Fluorescence telescopes measure the longitudinal EAS development in the atmosphere, which provides unique information on the primary cosmic ray's type and a calorimetric measurement of its energy.The fluorescence light yield along the EAS depends on the air pressure, temperature and humidity at the point of emission. In addition, wavelengthdependent atmospheric attenuation affects the light intensity reaching the telescope. Thus, the intensities of the fluorescence bands must be known for atmospheric conditions corresponding to the EAS development in the atmosphere, which ranges between about 2 km and 15 km above sea level. Early measurements of the fluorescence yield include those with low-energy stopped-particles in air by Bunner [3] and with electrons in air by Davidson and O'Neil [4]. A * corresponding author Email address: priviter@kicp.uchicago.edu (P. Privitera). The AIRFLY (AIR FLuorescence Yield) Collaboration has carried out an extensive program of measurements to significantly improve the precision on the fluorescence light yield. The fluorescence emission was studied as a function of the kinetic energy, ranging from keV to GeV, of particle beams at several accelerators [11]. The relative intensities of 34 fluorescence bands in the wavelength range from 284 to 429 nm, together with their pressure dependence, were reported in [12]. The temperature and humidity dependence of the main fluorescence bands was also measured [13]. These measurements have provided the most complete and consistent set of fluorescence yield data for UHECR calibration, establishing the relative ...

Background: Angiogenesis is critical for breast cancer progression. Within tumors, non-neoplastic cells assist tumor growth by producing growth factors and pro-angiogenic cytokines. Studies have demonstrated that tumor-associated macrophages (TAMs) are recruited to tumors before malignant conversion and are essential for promoting angiogenesis. We sought to study the role that macrophage phenotype—classically activated (M1) and alternatively activated (M2)—plays in the subsequent activation of the angiogenic pathway, with the goal of understanding the mechanisms underlying angiogenesis in the different molecular subtypes of breast cancer.Methods: 128 matching breast tumors, DCIS and normal tissues were obtained from the University of Chicago Breast Cancer SPORE tissue bank under IRB approved protocols. Tissue microarrays were constructed and molecular subtype was assigned based on immunohistochemical (IHC) staining into the following groups: luminal A (ER+, PR+, HER2-), luminal B (ER+, HER2+ or ER+, PR-), HER2-like (ER-, HER2+) and basal-like (ER-, HER2-, EGFR+ and/or CK5/6+). Macrophage phenotype was determined using double staining with CD68/CD163 (M2) and CD68/CD80 (M1). Microvessel density (MVD) was measured by IHC staining using anti-CD34. Staining quantification was performed independently by two pathologists. To control for intra-individual correlation, linear mixed-effects models were used to compare differences in % of M1 and M2 with disease progression. To evaluate the association of MVD with % of M1 and M2, bivariate plots were generated and Pearson's correlation coefficients were calculated. Spearman's correlation coefficients were used for the correlation between macrophage phenotype and tumor stage and grade. The Kaplan-Meier method was used to calculate overall survival.Results: Of the tumors studied, 88% were stage I-II. 17% were grade 1, 39% grade 2 and 44% grade 3. 70 were luminal A, 36 basal-like, 9 HER2-like and 6 luminal B. The ratio of M2:M1 increased with disease progression from normal breast to DCIS to invasive cancer (p<0.001). Increased M2% was associated with high tumor grade, increased MVD and decreased overall survival (all p<0.001). M1% was associated with low tumor grade (<0.001), but was not significantly associated with MVD or overall survival. Both the HER2-like and basal-like subtypes have significantly higher % M2 as compared to the luminal A subtype (p<0.001).Discussion: There are several studies which suggest that activated TAMs are responsible for the secretion of pro-angiogenic cytokines which stimulate neovascularization. To our knowledge, this is the first study that has correlated macrophage phenotype to breast molecular subtype and MVD in human breast tumors. Our findings suggest that the M2 macrophage phenotype is associated with aggressive histopathologic features and poor clinical outcome. Inhibiting the M2 macrophage may prevent the release of pro-angiogenic factors, and might be an effective approach at preventing neovascularization and improving patient outcomes. Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 107.