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961.
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Effect of reserpine (Serpasil) on oxygen consumption of euthyroid,hypothyroid, and hyperthyroid guinea pigs 总被引:2,自引:0,他引:2
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E. BRABANTS K. HEYNS S. DE SMET P. DEVREKER J. INGELS N. DE CABOOTER V. DEBACKER M. DULLAERS J.P. VAN MEERBEECK B. VANDEKERCKHOVE K.Y. VERMAELEN 《Cytotherapy》2018,20(9):1164-1181
Background
Many efforts have been devoted to improve the performance of dendritic cell (DC)–based cancer vaccines. Ideally, a DC vaccine should induce robust type 1–polarized T-cell responses and efficiently expand antigen (Ag)-specific cytotoxic T-cells, while being applicable regardless of patient human leukocyte antigen (HLA) type. Production time should be short, while maximally being good manufacturing practice (GMP)–compliant. We developed a method that caters to all of these demands and demonstrated the superiority of the resulting product compared with DCs generated using a well-established “classical” protocol.Methods
Immunomagnetically purified monocytes were cultured in a closed system for 3 days in GMP-compliant serum-free medium and cytokines, and matured for 24 h using monophosphoryl lipid A (MPLA)+ interferon-gamma (IFN-γ). Mature DCs were electroporated with messenger RNA (mRNA) encoding full-length antigen and cryopreserved. “Classical” DCs were cultured for 8 days in flasks, with one round of medium and cytokine supplementation, and matured with tumor necrosis factor alpha (TNF-α) + prostaglandin E2 (PGE2) during the last 2 days.Results
Four-day MPLA/IFN-γ–matured DCs were superior to 8-day TNF-α/PGE2–matured DCs in terms of yield, co-stimulatory/co-inhibitory molecule expression, resilience to electroporation and cryopreservation and type 1–polarizing cytokine and chemokine release after cell thawing. Electroporated and cryopreserved DCs according to our protocol efficiently present epitopes from tumor antigen-encoding mRNA, inducing a strong expansion of antigen-specific CD8+ T-cells with full cytolytic capacity.Conclusion
We demonstrate using a GMP-compliant culture protocol the feasibility of generating high yields of mature DCs in a short time, with a superior immunogenic profile compared with 8-day TNF-α/PGE2–matured DCs, and capable of inducing vigorous cytotoxic T-cell responses to antigen from electroporated mRNA. This method is now being applied in our clinical trial program. 相似文献968.
969.
The contribution of pre-defoliation reserves and current assimilates to leaf and root growth was examined in Lolium perenne L. during regrowth after defoliation. Differential steady-state labelling with 13C (CO2 with δ13C = -0.0281 and -0.0088) and 15N (NO3? with 1.0 and 0.368 atom percentage, i.e. δ15N = 1.742 and 0.0052, respectively) was applied for 2 weeks after defoliation. Rapidly growing tissues were isolated, i.e. the basal elongation and maturation zones of the most rapidly expanding leaves and young root tips, with a biomass turnover rate > 1 d?1. C and N weights of the elongation zone showed a transient decline. The dry matter and C concentration in fresh biomass of leaf growth zones transiently decreased by up to 25% 2 d after defoliation, while the N concentration remained constant. This ‘dilution’ of growth zone C indicates a decreased net influx of carbohydrates relative to growth-related influx of water and N in expanding cells, immediately after defoliation. Recovery of the total C and N weights of the leaf elongation zone coincided with net incorporation of currently absorbed C and N, as shown by the kinetics of δ13C and atom percentage 15N in the growth zones after defoliation. C isotope discrimination (Δ13C) in leaf growth zones was about 23‰, 1–2‰ higher than the Δ in root tips. Δ15N in the leaf and root growth zones was 10±3‰. The leaf elongation zones (at 0–0.03 m from the tiller base) and the distant root tips (about 0.2 m from the base) exhibited similar kinetics of current C and N incorporation. The amount of pre-defoliation C and N in the growth zones, expressed as a fraction of total C and N, decreased from 1.0 to 0.5 at 3 (C) and 5 (N) d after defoliation, and to 0.1 at 5 (C) and 14 (N) d after defoliation. Thus, the dependence of growth zones on current assimilate supply was significant, and stronger for C than for N. The important roles of current assimilates (as compared to pre-defoliation reserves) and ‘dilution’ of dry matter in regrowth after defoliation are discussed in relation to the method of labelling and the functional and morphological heterogeneity of shoot tissues. 相似文献
970.
WILLEM DE WINTER 《Biology & philosophy》1997,12(2):149-184
The beanbag genetics controversy can be traced from the dispute between Fisher and Wright, through Mayr's influential promotion of the issue, to the contemporary units of selection debate. It centers on the claim that genic models of natural selection break down in the face of epistatic interactions among genes during phenotypic development. This claim is explored from both a conceptual and a quantitative point of view, and is shown to be defective on both counts.Firstly, an analysis of the controversy's theoretical origins demonstrates that this claim derives from a misinterpretation of the conceptual foundations of Fisher's genetical theory of natural selection, and confounds his fundamentally different concepts of the average excess and average effect of a gene. Secondly, an extension of the genic approach is proposed which models the dynamics of selection among epistatically interacting complexes of many genes. Paradoxically, this preliminary, but fundamentally genic model provides quantitative support for some controversial qualitative claims regarding the evolutionary consequences of strong gene interactions made by opponents of genic selectionism, including Mayr's theory of peripartric speciation. These findings foster hope that the proposed approach may eventually nudge the beanbag controversy out of its conceptual trenches into a more empirically oriented dialogue. 相似文献