Cytotoxicity assay trypan blue

A variety of approaches are routinely used to qualitatively and/or quantitatively assess toxicant-induced cell death in vitro. For example, dye-based cytotoxicity assays are widely employed to assess the viability of cells in culture. While initially developed for use in mammalian cell lines, these approaches have been successfully applied in toxicological studies using fish cell lines27. The principle behind many of these assays is the ability of metabolically active cells to either exclude (e.g. trypan blue), incorporate (e.g. neutral red), and/or metabolically transform (e.g. 3-[4,5-dimethylthiazol-3-yl]-2,5-diphenyltetrazolium bromide (MTT)) colorimetric... 

It is well documented that normal human bronchial epithelial cells release a variety of cytokines and chemokines, and proinflammatory cytokines such as IL-la, IL-1 3, and TNF-a stimulate their production in vitro (Fig. 11) [61], We cultured human normal and transformed bronchial epithelial cells, and studied the effect of EM, CAM, and RXM on IL-6 [17], IL-8 [60, 62] and GM-CSF [63] production. Among the antimicrobes tested, only 14-membered-ring macrolides EM, CAM, and RXM showed an inhibitory action on cytokine release by unstimulated and cytokine-stimulated human bronchial epithelial cells (Fig. 12). In contrast, a 16-membered ring macrolide josamycin (JM) failed to show such effects. LDH release assay, a trypan blue dye exclusion test, and a colorimetric MTT assay showed that this effect was not due to cytotoxicity. Percent inhibition of IL-8 protein release in human primary bronchial epithelial cells was 25.0 5.67% at lO M, which is comparable with clinically observed serum concentration. 

Cytotoxicity is the most important parameter to evaluate the biocompatibility of biodegradable polymers in vitro. Various assays are available to measure cell viability after exposure to polymer extracts, such as lactate dehydrogenase leakage assay (LDH), neutral red uptake assay (NRU), and trypan blue assay. Table 20.5 summarizes the different types... 

Moorthy et al. [32] have synthesized 5-isopropylidiene derivatives of 3-dimethyl-2-thio-hydantoin XXVI, 3-ethyl-2-thio-2,4-oxazoIidinedione XXVII, and 5-benzilidene-3-ethyl rhodanine XXVIII, which are cytotoxic against leukemic cell line in concentration-dependent manner. The results of the trypan blue and MTT assays indicated that the compound XXVIII found to be fivefold to sevenfold more potent than XXVI and XXVII with IC5o<10 pM. XXVIII found to affect DNA replication by inducing a block at S phase on the basis of cell cycle analysis and tritiated thymidine assays. Moreover, the treatment of XXVIII led to increased level of reactive oxygen species (ROS) production and DNA strand breaks. This suggests the activation of apoptosis for induction of cell death. 

Murinda, S., Rashid, K., Roberts, R., 2003. In vitro assessment of the cytotoxicity of nisin, pediodn, and selected coUcins on simian virus 40—transfected human colon and Vero monkey kidney cells with trypan blue staining viability assays. Journal of Food Protection 66, 847-853. 

Toxicity. Toxicity is foimd to be a minor problem and many vesicle systems have passed standard toxicity tests. The hydrophilic PEO block effectively screens the influence of the hydrophobic cores on timescales of the measured circulation half-life ri/2. With respect to long-time applications, PEE is structurally similar to low-density polyethylene, which is commonly used in implants and is generally considered bioinert (214). PB is also understood to be bioinert as it is commonly chosen for the hydrophobic block in triblock copoljuners (215,216). In a more prolonged model test of biocompatibility, nondiflferentiated C2C12 cells were incubated with poljunersomes. The cells remained well spread with no evidence of cytotoxicity. As shown by the Trypan blue exclusion assay, polymersomes had no significant effect on cell survival. 

Figure 6. Summary on the cytotoxic effects of RST extract, tetrandrine, and fangchinoline on PMA-activated neutrophils. Cell viability was determined by counting the vital cell by trypan blue (0.4%) exclusion assay in the end of the...

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