PubMed Health⌕ Search
Home/Archive/PubMed

PubMed · 9155642

Nitric oxide increased interleukin-4 expression in T lymphocytes.

R H Chang·M H Feng·W H Liu·M Z Lai
View original source ↗Export metadata ↓

Abstract

Nitric oxide (NO) is a regulator of many biological functions including T helper 1 (Th1)/T helper 2 cells balance. It has been demonstrated that NO inhibits the secretion of interleukin-2 (IL-2) and interferon-gamma on Th1 cells. Here we showed that, in addition to the suppression of IL-2 production, NO-generating agents sodium nitroprusside (SNP) and S-nitroso-N-acetylpenicillamine (SNAP) increased the secretion of IL-4 both in Th2 clones and EL4 T cells. The additive effect was dependent on the dose of SNP and SNAP. Augmentation of IL-4 production was detected with 1 microM SNP, and up to threefold increase in IL-4 secretion could be observed with higher concentrations of SNP/SNAP. NO also weakly increased the activation of IL-4 promoter. In contrast, NO markedly inhibited the induction of IL-2 promoter, which could account for most of the reduction in IL-2 production. Analysis of the transcriptional elements on IL-2 and IL-4 promoters revealed a selective inactivation of NF-kappa B and NF-AT. It is suggested that despite the complex feedback network regulating NO production, the enhanced IL-4 expression would lead to the expansion of Th2 cells once NO is generated.

Explore related subjects

Cell Culture TechniquesDose-Response Relationship, ImmunologicInterleukin-2Interleukin-4Nitric OxideNitroprussidePenicillamineS-Nitroso-N-AcetylpenicillamineT-LymphocytesTh2 CellsTumor Cells, CulturedJournal ArticleResearch Support, Non-U.S. Gov't

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

R H Chang, M H Feng, W H Liu, M Z Lai. 1997. Nitric oxide increased interleukin-4 expression in T lymphocytes.. https://doi.org/10.1111/j.1365-2567.1997.00364.x

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related citations

PubMed2007

Cell patterning using magnetite nanoparticles and magnetic force.

Technologies for fabricating functional tissue architectures by patterning cells precisely are highly desirable for tissue engineering. Although several cell patterning methods such as microcontact printing and lithography have been developed, these methods require specialized surfaces to be used as substrates, the fabrication of which is time consuming. In the present study, we demonstrated a simple and rapid cell patterning technique, using magnetite nanoparticles and magnetic force, which enables us to allocate cells on arbitrary surfaces. Magnetite cationic liposomes (MCLs) developed in our previous study were used to magnetically label the target cells. When steel plates placed on a magnet were positioned under a cell culture surface, the magnetically labeled cells lined on the surface where the steel plate was positioned. Patterned lines of single cells were achieved by adjusting the number of cells seeded, and complex cell patterns (curved, parallel, or crossing patterns) were successfully fabricated. Since cell patterning using magnetic force may not limit the property of culture surfaces, human umbilical vein endothelial cells (HUVECs) were patterned on Matrigel, thereby forming patterned capillaries. These results suggest that the novel cell patterning methodology, which uses MCLs, is a promising approach for tissue engineering and studying cell-cell interactions in vitro.

Cell Culture Techniques↗
PubMed2007

Investigation of metabolic objectives in cultured hepatocytes.

Using optimization based methods to predict fluxes in metabolic flux balance models has been a successful approach for some microorganisms, enabling construction of in silico models and even inference of some regulatory motifs. However, this success has not been translated to mammalian cells. The lack of knowledge about metabolic objectives in mammalian cells is a major obstacle that prevents utilization of various metabolic engineering tools and methods for tissue engineering and biomedical purposes. In this work, we investigate and identify possible metabolic objectives for hepatocytes cultured in vitro. To achieve this goal, we present a special data-mining procedure for identifying metabolic objective functions in mammalian cells. This multi-level optimization based algorithm enables identifying the major fluxes in the metabolic objective from MFA data in the absence of information about critical active constraints of the system. Further, once the objective is determined, active flux constraints can also be identified and analyzed. This information can be potentially used in a predictive manner to improve cell culture results or clinical metabolic outcomes. As a result of the application of this method, it was found that in vitro cultured hepatocytes maximize oxygen uptake, coupling of urea and TCA cycles, and synthesis of serine and urea. Selection of these fluxes as the metabolic objective enables accurate prediction of the flux distribution in the system given a limited amount of flux data; thus presenting a workable in silico model for cultured hepatocytes. It is observed that an overall homeostasis picture is also emergent in the findings.

Cell Culture Techniques↗
PubMed2007

Quantitation of interaction of lipids with polymer surfaces in cell culture.

As cell culture medium development efforts have progressed towards leaner, serum-free, and chemically defined formulations, it has become increasingly important to ensure that the appropriate concentrations of all nutrients are maintained and delivered at point of use. In light of concurrent efforts to progress to disposable polymeric storage and culture platforms, the characterization and control of medium component interactions with container surfaces can be a key issue in ensuring consistent delivery of these medium formulations. These studies characterize the interactions of lipids with culture surfaces typically encountered in the bioprocess industry using model systems. The extent and kinetics of lipid association with polymeric surfaces were determined using radio-labeled linoleic acid and cholesterol. The effect of methyl-beta-cyclodextrin, a component commonly used to solubilize lipids in culture media, on association kinetics was also examined. In addition, loss of lipids across a sterilizing membrane filter was quantified. We find that there is potential for significant loss of hydrophobic components due to non-specific binding to surfaces at timescales relevant to a typical cell culture process. The extent of loss is dependent on the nature of the hydrophobic component as well as the type of surface. These studies highlight the potential of the extracellular environment to modify medium composition and also emphasize the importance of medium formulation strategies, including those used in the delivery of hydrophobic components. It is noted, however, that the level of loss is very dependent on the specific system including the composition of the culture medium used.

Cell Culture Techniques↗