The Expression and Biological Significance of PD-L1 on Lung Cancer Cell Lines

Background and objective Tumor-associated PD-L1 expression was recently shown to promote T-cell apoptosis and proposed as a potential mechanism of immune evasion by tumors. On the basis of the ability of tumor-associated PD-L1 to mediate activated T-cell death, it is likely that manipulation of the PD-L1 pathway at defined time points during the development of the T-cell antitumor immune response can enhance the efficacy of T-cell-based immunotherapy. Here, the levels of expression of PD-L1 on lung cancer cell lines and its role in interaction of CTL and target cells was investigated. Methods Human PBMC derived DCs were loaded with apoptotic tumor cells and stimulated by CD40 mAb (5C11). Tumor specific CTL was generated in vitro by autologous T cells co-cultured with mature DCs. Expression of PD-L1 on lung cancer cell lines H1299 and A549 were analyzed by FCM. JAM assay was used to detect the cytolytic activity of CTL with or without blocking PD-L1 by PD-L1 mAb respectively. The concentrations of IFN-γ in supernatants from distinct groups were analyzed by ELISA. Results Tumor cells-loaded mature DCs could induce the generation of the tumor specific CTL. Expression of PD-L1 was low on A549 cell, but high on H1299 cell. Blockade of PD-L1 on A549 could not improve cytolytic effect of CTL on target cells and IFN-γ production, but fragmentation of H1299 cells and IFN-γ production were significantly enhanced by the combination of PD-L1 mAb and CTL. Conclusion Expression of PD-L1 on lung cancer cell line can decrease the cytolytic effect of CTL on target cells

Revision of the orb-weaver spider genus Gea C.L. Koch, 1843 (Araneae, Araneidae) from China

The orb-weaver spider genus Gea C.L. Koch, 1843 from China is revised, and three species including one new species, are recognized: Gea jingdong Mi, Wang & Gan, sp. nov. (♂♀) from Yunnan; Gea spinipes C.L. Koch, 1843 (♂♀) from Guangdong, Guangxi, Guizhou, Hainan, Taiwan, and Yunnan; and Gea subarmata Thorell, 1890 (♂♀) from Guangxi and Hainan. Gea subarmata is newly recorded in China

Deficiency of Brummer Impaires Lipid Mobilization and JH-Mediated Vitellogenesis in the Brown Planthopper, Nilaparvata lugens

Provisioning of sufficient lipids and vitellogenin to the oocytes is an indispensable process for fecundity of oviparous insects. Acute mobilization of lipid reserves in insects is controlled by the Brummer (Bmm), an orthologous of human adipose triglyceride lipase (ATGL). To investigate the functional roles of brummer-mediated lipolysis in the fecundity of the brown planthopper, Nilaparvata lugens, RNA interference (RNAi) analyses were performed with double-stranded RNA (dsRNA) against NlBmm in adult females. Knockdown of NlBmm expression resulted in obesity and blocked lipid mobilization in the fat body. In addition, NlBmm silencing led to retarded ovarian development with immature eggs and less ovarioles, decreased number of laid eggs, prolonged preoviposition period and egg duration. Furthermore, severe reductions of vitellogenin and its receptor abundance were observed upon NlBmm knockdown. The transcript levels of NlJHE (juvenile hormone esterase) which degrades JH were up-regulated, whereas the expression levels of JH receptors NlMet (Methoprene-tolerant) and NlTai (Taiman) and their downstream transcription factors NlKr-h1 (Krüppel-homolog 1) and NlBr (Broad-Complex) were down-regulated after suppression of NlBmm. JH-deficient females exhibited impaired vitellogenin expression, whereas JH exposure stimulated vitellogenin biosynthesis. Moreover, JH topical application partially rescued the decrease in vitellogenin expression in the NlBmm-deficient females. These results demonstrate that brummer-mediated lipolytic system is essential for lipid mobilization and energy homeostasis during reproduction in N. lugens. In addition to the classical view of brummer as a direct lipase with lipolysis activity, we propose here that brummer-mediated lipolysis works through JH signaling pathway to activate vitellogenesis and oocyte maturation that in turn regulates female fecundity

Adipokinetic Hormone Receptor Mediates Trehalose Homeostasis to Promote Vitellogenin Uptake by Oocytes in Nilaparvata lugens

Adipokinetic hormones (AKHs) are well known to mobilize lipids and carbohydrates for energy-consuming activities in insects. These neuropeptides exert their functions by interacting with AKH receptors (AKHRs) located on the plasma membrane of fat body cells, which regulates energy mobilization by stimulating lipolysis of triacylglycerols (TAG) to diacylglycerols (DAG) and conversion of glycogen into trehalose. Here, we investigated the roles of AKH/AKHR signaling system in trehalose metabolism and vitellogenesis during female reproduction in the brown planthopper, Nilaparvata lugens. Knockdown of AKHR expression by RNA interference (RNAi) resulted in a decrease of the circulating trehalose in hemolymph and significantly increased levels of two trehalases in fat bodies, indicating that the modulation of hemolymph trehalose levels by AKHR may be mediated by regulating trehalose degradation. In addition, adult females that had been injected with double-stranded RNA (dsRNA) for AKHR exhibited delayed oocyte maturation, prolonged pre-oviposition period, as well as decline in egg number and reduction in fecundity. Considering that these phenotypes resulting from AKHR silencing are similar to those of vitellogenin receptor (VgR) RNAi, we further analyzed a possible connection between AKHR and vitellogenesis. Knockdown of AKHR showed no effects on the Vg synthesis in fat bodies, whereas it significantly reduced the levels of VgR in ovaries. With RNAi-females, we observed an increase of Vg accumulation in hemolymph and a decrease of Vg deposition in ovaries. Moreover, the decrease in VgR expression and Vg incorporation by developing oocytes could be partially rescued by injection of trehalose into AKHR RNAi females. The present study has implicated trehalose in the AKH/AKHR signaling-mediated control of reproduction and provided new insight into mechanisms of AKH/AKHR regulation of trehalose metabolism in insect vitellogenesis, oocyte maturation and fecundity

On four new species of the orb-weaver spider genus Araneus Clerck, 1757 (Araneae, Araneidae) from southern China

Four new species of Araneus Clerck, 1757 from southern China are described: A. mayanghe Mi & Wang, sp. nov. (♂♀) from Guizhou, A. shiwandashan Mi & Wang, sp. nov. (♂♀) from Guangxi, and A. zhoui Mi & Wang, sp. nov. (♂♀) from Hainan are assigned to the A. sturmi group, and A. fenzhi Mi & Wang, sp. nov. (♂♀) from Hunan, Guizhou and Jiangxi is not assigned to any species group. A new combination is also proposed: Aoaraneus octumaculalus (Han & Zhu, 2010) comb. nov

Revision of the orb-weaver spider genus Gea C.L. Koch, 1843 (Araneae, Araneidae) from China

The orb-weaver spider genus Gea C.L. Koch, 1843 from China is revised, and three species including one new species, are recognized: Gea jingdong Mi, Wang & Gan, sp. nov. (♂♀) from Yunnan; Gea spinipes C.L. Koch, 1843 (♂♀) from Guangdong, Guangxi, Guizhou, Hainan, Taiwan, and Yunnan; and Gea subarmata Thorell, 1890 (♂♀) from Guangxi and Hainan. Gea subarmata is newly recorded in China

On four new species of the orb-weaver spider genus Araneus Clerck, 1757 (Araneae, Araneidae) from southern China

Four new species of Araneus Clerck, 1757 from southern China are described: A. mayanghe Mi & Wang, sp. nov. (♂♀) from Guizhou, A. shiwandashan Mi & Wang, sp. nov. (♂♀) from Guangxi, and A. zhoui Mi & Wang, sp. nov. (♂♀) from Hainan are assigned to the A. sturmi group, and A. fenzhi Mi & Wang, sp. nov. (♂♀) from Hunan, Guizhou and Jiangxi is not assigned to any species group. A new combination is also proposed: Aoaraneus octumaculalus (Han & Zhu, 2010) comb. nov