Objective To investigate the regulatory role of the programmed cell death protein 1 (PD-1) and its ligand programmed cell death protein ligand 1 (PD-L1) signaling on the subtypes and functions of natural killer (NK) cells at the maternal-fetal interface during the second trimester in mice following Toxoplasma gondii infection during the first trimester. Methods Twelve 6- to 8-week-old female mice of the C57BL/6J strain were divided into a control group and an infection group, of 6 mice in each group. On the 6.5th day of pregnancy (Gd6.5), each pregnant mouse in the infection group was intraperitoneally injected with 150 tachyzoites of the Toxoplasma gondii PRU strain, while mice in the control group were injected with an equal volume of physiological saline. On the 12.5th day of pregnancy (Gd12.5), uterus and placenta tissues were sampled from pregnant mice for pathological observations, and the mRNA expression levels of PD-1, PD-L1, and tumor necrosis factor-α (TNF-α) were quantified in uterus and placenta tissues. The PD-1 and DX5 expression was measured on NK cells at the maternal-fetal interface using flow cytometry. In addition, the in vitro JEG-3 trophoblast cells and NK-92MI cells co-culture system was established as the control group, and the addition of T. gondii tachyzoites in the co-culture system served as the infection group. The PD-1, PD-L1, and DX5 mRNA expression was quantified in cells using real-time fluorescence quantitative reverse transcription PCR (RT-qPCR) assay, and the TNF-α concentration was measured in the cell culture supernatant using enzyme-linked immunosorbent assay (ELISA). Results On Gd12.5, clear and intact cellular structures of placental decidual tissues were seen in pregnant mice in the control group, with no remarkable abnormal changes found in the uterine columnar epithelial cells, and inflammatory cell infiltration and blood stasis at varying degrees were found in uterine and placental tissues from pregnant mice in the infection group. The relative PD-1, PD-L1, and TNF-α mRNA expression was (1.004 ± 0.004), (1.001 ± 0.001), and (1.001 ± 0.001) in uterine tissues from pregnant mice in the control group and (2.480 ± 0.720), (3.355 ± 0.920), and (2.391 ± 0.073) in the infection group, respectively. The relative PD-1, PD-L1, and TNF-α mRNA expression was (1.007 ± 0.010), (1.006 ± 0.006), and (1.001 ± 0.001) in the uterine tissues in the control group and (6.948 ± 1.918), (3.225 ± 1.034), and (1.536 ± 0.150) in the infection group, respectively. The relative PD-1, PD-L1, and TNF-α mRNA expression was higher in both the uterine (t = 3.55, 4.43 and 33.02, all P values < 0.05) and placental tissues (t = 5.36, 3.72 and 6.18, all P values < 0.05) in the infection group than in the control group. Flow cytometry showed that the proportions of PD-1⁺ NK cells, PD-1⁺ DX5⁺ NK cells, and DX5⁺ NK cells were (12.200 ± 1.082)%, (9.373 ± 7.728)%, and (44.000 ± 4.095)% in uterine tissues from pregnant mice in the control group, and (21.733 ± 1.630)%, (18.767 ± 1.242)%, and (73.367 ± 0.611)% in the infection group, respectively. The proportions of PD-1⁺ NK cells, PD-1⁺ DX5⁺ NK cells, and DX5⁺ NK cells were (1.100 ± 0.510)%, (2.277 ± 1.337)%, and (96.167 ± 2.831)% in placental tissues from mice in the control group, and (26.867 ± 9.722)%, (23.433 ± 6.983)%, and (82.467 ± 2.248)% in the infection group, respectively. The proportions of PD-1⁺ NK cells (t = 8.45, P < 0.05) and DX5⁺ NK cells (t = 12.29, P < 0.05) were higher in uterine tissues from pregnant mice in the infection group than in the control group, and no significant difference was seen in the proportion of PD-1⁺ DX5⁺ NK cells (Z = -1.09, P > 0.05). The proportions of PD-1⁺ NK cells (t = 4.58, P < 0.05) and PD-1⁺ DX5⁺ NK cells (t = 5.15, P < 0.05) were higher in placental tissues from pregnant mice in the infection group than in the control group, while the proportion of DX5⁺ NK cells was lower in the infection group than in the control group (t = -6.56, P < 0.05). RT-qPCR assay revealed that the relative PD-1, PD-L1, and DX5 mRNA expression was (1.010 ± 0.005), (1.002 ± 0.003), and (1.001 ± 0.001) in the JEG-3 cells and NK92MI cells co-culture system and (3.638 ± 1.258), (0.397 ± 0.158), and (4.267 ± 1.750) in the control group, and ELISA measured that the TNF-α concentration was higher in the cell culture supernatant in the infection group [(22.056 ± 3.205) pg/mL] than in the control group [(12.441 ± 0.001) pg/mL] (t = 5.20, P < 0.05). The PD-1(t = 3.62, P < 0.05) and DX5 mRNA expression (t = 3.23, P < 0.05) was higher in the infection group than in the control group, and the PD-L1 mRNA expression was lower in the infection group than in the control group (t = -6.63, P < 0.05). Conclusions Following T. gondii infection, both PD-L1 expression and PD-1 expression on DX5⁺ NK cells at the maternal-fetal interface are upregulated in mice during the second trimester; however, the proportion of DX5⁺ NK cells decreases. These findings suggest that PD-1/PD-L1 signaling may suppress NK cell functions by modulating DX5⁺ NK cell subsets.

Objective To investigate the effects of glutamine (Gln) on proliferation and survival of small cell lung cancer H446 cells, and further to explore the potential mechanism. Methods The proliferation of H446 cells was detected at different time points (0, 24, 48, 72 and 96 h) by CCK-8 assay in Gln (+) group and Gln (-) group, and an optimal time was selected. Under the optimal time, Annexin V-FITC/PI staining, CellTiter-Glo? assay kit and flow cytometer were used to detect cell survival, cellular adenosine triphosphate (ATP) and reactive oxygen species (ROS) levels. Gln (-) group was used as the control group, under the condition of Gln deficiency, cellular ATP, cell proliferation and survival were detected after adding oxaloacetic acid (OAA) or dimethyl-α-ketoglutarate (DM-αKG). Gln (-) group was used as the control group, cellular ROS, cell proliferation, colony and survival were detected after treated with ROS scavenger N- acetyl cysteine (NAC). With different concentrations (0, 2, 5, 10 μmol/L) of glutaminase inhibitor BPTES, the optimal concentration was selected through the colony assay. The cellular ATP and ROS levels and cell proliferation were detected under the optimal concentration. H446 cells were treated with bis-2-(5-phenylacetamido-1,2,4-thiadiazol-2-yl) ethyl sulfide (BPTES), ROS inducer hydrogen peroxide (H2O2) or the combination of them, and cell survival ratio was compared between two groups. Results The proliferation levels of H446 cells at 24, 48, which were decreased most significantly in 72 h in Gln (-) group. When 72 h was used as the optimal time, the cell survival ratio and ATP level were decreased, and the ROS level was increased, in Gln (-) group compared with those of Gln (+) group (P<0.05). There was a higher survival ratio in H446 cells in Gln (-)+OAA group and Gln (-)+DM-αKG group than that of Gln (-) group (P<0.05), but there were no significant differences in cell proliferation and ATP levels between Gln (-) group, Gln (-)+OAA group and Gln (-)+DM-αKG group. The ROS level was reduced, the cell proliferation, colony level and survival ratio were increased in Gln (-)+NAC group compared with those of Gln (-) group (P<0.05). Cloning assay showed that 10μmol/L was the optional concentration. Under this concentration, the proliferation and ATP level were decreased in Gln(+)+BPTES group (P<0.05), and cellular ROS level was up-regulated compared with Gln(+) group. The survival ratio was significantly lower in BPTES+H 2O2 group compared with BPTES (+) group or H2O2 (+) group. Conclusion Glutamine deficiency inhibits the proliferation and survival ratio of H446 cells through enhancing ROS level. BPTES and H2O2 show synergistically inhibitory effect on the survival of H446 cells.

Objective To observe the effect of electro-acupuncture therapy (ET) on the expression of sodium channel Na(v) 1.1 in rats after acute cerebral ischemia and the mechanism of any protective function of ET.Methods A model of focal acute cerebral ischemia was established by occluding the right middle cerebral artery.One hundred and eighty healthy SD rats were randomly divided into a sham operation control (SC) group, an ischemia control (IC) group, a real ET group and a false ET group, with 45 in each group. Immunohistochemistry and real-time polymerase chain reaction (PGR) methods were used to detect Na(v)1. 1 expression. 2,3,5-triphenyl tetrazolium chloride (TTC) staining was used to detect infarct volume. Neurological examination and grading was carried out at 6 hours and then 1, 2, 3 and 7 days after inducing ischemia. Results The gradings and infarction volume ratios of the rats in the IC group were the most serious, while in the real ET group the severity was much less at each time point. Compared with the SC group, the expression of Na(v) 1.1 was significantly up-regulated in the IC group. The expression of Na(v) 1.1 was increased at the 6th hour, then down-regulated to the lowest level at day 1,then from the 2nd to the 7th day was up-regulated again. The expression of Na(v) 1.1 in the real ET group was significantly lower than in the IC group. Although the expression of Na(v)1.1 in the false ET group was low compared with the IC group, the difference was not significant. The difference between the real ET group and the false ET group was significant, however. Conclusions ET can reduce damage from cerebral ischemia and benefit the recovery of neural function. ET can also could regulate the expression of Na(v)1.1 after acute cerebral ischemia, which may be an important mechanism for neural function recovery.

AIM: To study the effect of nasal mucosal tolerance to E-selectin on cerebral ischemia-reperfusion injury.METHODS: Two different doses(single and booster) of E-selectin or PBS were dropped into membrana mucosa nasi of rats.The middle cerebral artery occlusion(MCAO) model referring to Zea Longa method with modifications was performed 48 h after the last dose of E-selectin or PBS.After 2 h ischemia and 22 h reperfusion,the numbers of CD3+CD4+T-lymphocyte and CD3+CD8+T lymphocyte subgroup in the blood were examined with flow cytometry.Rats were killed,then part of the animals was used to measure the cerebral infarction volume by TTC staining.mRNA expressions of E-selectin,ICAM-1 and lymphocyte function-associated antigen-1(LFA-1) were determined by RT-PCR and activity of SOD was determined by xanthinoxidanse method in ischemic cortex of the other part of animals.RESULTS: The ratio of the numbers of CD3+CD4+T-lymphocytes and CD3+CD8+T-lymphocytes increased in E-selectin single pretreatment group(P