Adoptive transfer of FTY720-treated immature bone marrowderived dendritic cells(BMDCs) significantly reduced the spontaneous resorption rate in the CBA/J ×DBA/2 mouse model

Objective To investigate the effect of FTY720-treated immature bone marrow-derived dendritic cells（BMDCs） on the embryo resorption rate in the CBA/J× DBA/2 abortion mouse model.Methods The dendritic cells（DCs） were derived from bone marrow of DBA/2 mice, and then co-cultured with FTY720. The abortion mouse models were established by mating female CBA/J mice with DBA/2 mice. Via the CBA/J×DBA/2 abortion mouse model, six groups were established, group A： normal pregnancy model; group B： abortion mouse model with no treatment; group C： abortion mouse model injected with DC culture medium（DCCM）; group D： abortion mouse model injected with DC; group E： abortion mouse model injected with FTY720; group F： abortion model mouse injected with FTY720-DC. The differences were compared in the embryo resorption rates of the CBA/J ×DBA/2 abortion mouse model treated with FTY720-DC or different controls observed on gestation day 12 to 14, and then the microenvironment in murine pregnancy was investigated.Results The embryo resorption rate was statistically significantly decreased in group D and group E when they compared with group B and group C（P〈0.05, respectively）.Furthermore, the embryo resorption rate in group F showed a statistically significant decrease when compared with the other groups except group A（P〈0.01）. These resultssuggest that FTY720-DCs possess a notable advantage over DCs or FTY720 in reducing the embryo resorption rate of the abortion mouse model. The percentage of Th17（IL-17＋CD4＋T cells） in peripheral blood mononuclear cell（PBMC） in the abortion mouse model was 4.35%±0.34% before treated with FTY720-DC, and was1.34%±0.28% after treated with FTY720-DC（P〈0.01）. The percentage of Tregs（CD4~＋CD25~＋Foxp3~＋T cells） in PBMC was significantly increased in group F（8.35%±1.80%） as compared with group B（2.68%±0.65%）（P〈0.01）.Conclusion Adoptive transfer of FTY720-DC can statistically significantly reduce the embryo resorption rate in the CBA/J×DBA/2 abortion mouse model. The lower embryo resorption rate in the FTY720-DC treated abortion mouse model may be caused by the imbalance of Treg/Th17.

Effects of N on Plant Response to Heat-wave:A Field Study with Prairie Vegetation

More intense, more frequent, and longer heat-waves are expected in the future due to global warming, which could have dramatic ecological impacts. Increasing nitrogen （N） availability and its dynamics will likely impact plant responses to heat stress and carbon （C） sequestration in terrestrial ecosystems. This field study examined the effects of N availability on plant response to heat-stress （HS） treatment in naturally-occurring vegetation. HS （5 d at ambient or 40.5 ℃） and N treatments （±N） were applied to 16 1 m^2 plots in restored prairie vegetation dominated by Andropogon gerardii （warm-season C4 grass） and Solidago canadensis （warm-season C3 forb）. Before, during, and after HS, air, canopy, and soil temperature were monitored; net CO2 assimilation （Pn）, quantum yield of photosystem Ⅱ （ФpsⅡ）, stomatal conductance （gs）, and leaf water potential （ψw） of the dominant species and soil respiration （Rsoll） of each plot were measured daily during HS. One week after HS, plots were harvested, and C% and N% were determined for rhizosphere and bulk soil, and above-ground tissue （green/senescent leaf, stem, and flower）. Photosynthetic N-use efficiency （PNUE） and N resorption rate （NRR） were calculated. HS decreased Pn, gs, ψw, and PNUE for both species, and ＋N treatment generally increased these variables （±HS）, but often slowed their post-HS recovery. Aboveground biomass tended to decrease with HS in both species （and for green leaf mass in S. canadensis）, but decrease with ＋N for A. gerardii and increase with ＋N for S. canadensis. For A. gerardii, HS tended to decrease N% in green tissues with ＋N, whereas in S. canadensis, HS increased N% in green leaves. Added N decreased NRR for A. gerardii and HS increased NRR for S. canadensis. These results suggest that heat waves, though transient, could have significant effects on plants, communities, and ecosystem N cycling, and N can influence the effect of heat waves.