scholarly journals The use of in vitro assays for the assessment of cytotoxicity on the example of MTT test

2018 ◽  
Vol 14 ◽  
pp. 23-32 ◽  
Author(s):  
Magdalena Twarużek ◽  
Ewa Zastempowska ◽  
Ewelina Soszczyńska ◽  
Iwona Ałtyn

In recent years, biological tests have been developed based on cell cultures and successfully used to the hygienic assess of a variety of samples. In vitro assays become the complement of conventional chemical methods. They do not narrow the results only to the quantitative and qualitative information on toxic substances, but also increase knowledge on the direct impact on the organism. They are also an alternative for animal testing, which are currently given up for ethical reasons. At present, the market is steadily increasing in the number of tests and bio-assay techniques. Based on our own studies we conclude that the MTT test is perfect as a diagnostic method for evaluating the cytotoxicity of materials of different composition such as mycotoxins, pesticides, bacterial cultures, moulds isolates, food, feed, as well as a vast spectrum of other environmental samples.

Impact ◽  
2021 ◽  
Vol 2021 (8) ◽  
pp. 44-45
Author(s):  
Hajime Kojima

Scientists are working to develop new and innovative alternatives to animal testing that don't rely on the use of animals. Takao Ashikaga, Hajime Kojima and Yoko Hirabayashi are part of JaCVAM which works to promote the use of alternatives to animal testing. The goal is to replace, reduce or refine (3Rs) the use of animal under International harmonization. Hirabayashi is also the representative of a research group that is funded by the AMED and the representative of a research group funded by the MHLW. A challenge the researchers are facing in their quest to ensure the welfare of experimental animals and also ensure the safety of various pharmaceutical and chemicals is the lack of biomarkers to more accurately predict toxicity for regulatory acceptance. This means that without animal testing more costly and complex non-animal methods are required and presents a barrier to the adoption of non-animal methods for international standerisation. As such, there is a need to develop an easy way to obtain a lot of information. Hirabayashi and the team are working on the development of AI that can be used to evaluate the safety of different compounds. The researchers are developing in vitro assays such as ordinary 2-dimensional culture, 3-dimensional culture including organoids or spheroids, reporter gene assay and organ-on-a chip; and in silico assays such as computer toxicology using QSAR and Read Across. The researchers hope that their innovative work will contribute to the 3Rs, benefiting animal welfare for regulatory use.


2020 ◽  
Vol 176 (1) ◽  
pp. 236-252 ◽  
Author(s):  
Maria T Baltazar ◽  
Sophie Cable ◽  
Paul L Carmichael ◽  
Richard Cubberley ◽  
Tom Cull ◽  
...  

Abstract Next-Generation Risk Assessment is defined as an exposure-led, hypothesis-driven risk assessment approach that integrates new approach methodologies (NAMs) to assure safety without the use of animal testing. These principles were applied to a hypothetical safety assessment of 0.1% coumarin in face cream and body lotion. For the purpose of evaluating the use of NAMs, existing animal and human data on coumarin were excluded. Internal concentrations (plasma Cmax) were estimated using a physiologically based kinetic model for dermally applied coumarin. Systemic toxicity was assessed using a battery of in vitro NAMs to identify points of departure (PoDs) for a variety of biological effects such as receptor-mediated and immunomodulatory effects (Eurofins SafetyScreen44 and BioMap Diversity 8 Panel, respectively), and general bioactivity (ToxCast data, an in vitro cell stress panel and high-throughput transcriptomics). In addition, in silico alerts for genotoxicity were followed up with the ToxTracker tool. The PoDs from the in vitro assays were plotted against the calculated in vivo exposure to calculate a margin of safety with associated uncertainty. The predicted Cmax values for face cream and body lotion were lower than all PoDs with margin of safety higher than 100. Furthermore, coumarin was not genotoxic, did not bind to any of the 44 receptors tested and did not show any immunomodulatory effects at consumer-relevant exposures. In conclusion, this case study demonstrated the value of integrating exposure science, computational modeling and in vitro bioactivity data, to reach a safety decision without animal data.


1985 ◽  
Vol 4 (2) ◽  
pp. 163-171 ◽  
Author(s):  
J. C. Lamb

Reproductive toxicity testing systems are used by national and international regulatory agencies. Protocols have not been standardized between agencies or even within certain agencies. Although there have been efforts at standardization, a certain amount of the differences between testing protocols is a reflection of the needs of the particular agency. New developments in in vitro techniques might lead to new test systems, but reproductive function is dependent upon the interaction of various cells and organs that cannot presently be copied in the test tube; this makes whole-animal testing systems a necessity. The present whole-animal models used by the Food and Drug Administration include the 3 segment reproduction studies used for testing drug safety and the multigeneration studies used for food additives. The Environmental Protection Agency has adopted 2 similar versions of a 2-generation study for the Office of Pesticide Programs and the Office of Toxic Substances. The National Toxicology Program, although not a regulatory agency, has taken a prominent role in reproductive toxicity testing, test system development, and test system evaluation. A new testing system, Fertility Assessment by Continuous Breeding (FACB), is currently being studied as a cost-effective and reliable alternative test system. The FACB protocol houses male and female mice as breeding pairs and removes offspring as soon as they are born during the first 14 weeks to allow continuous mating. Each breeding pair normally has up to 5 litters, and the last litter is saved to evaluate the second generation. The efficiency, reliability, and expense of the protocol are being compared to the existing testing systems.


2020 ◽  
Vol 48 (1_suppl) ◽  
pp. 18S-25S
Author(s):  
Jenny McCann ◽  
Terry McCann

The Lush Prize supports animal-free testing by awarding money prizes of up to £350,000 per year to the most effective projects and individuals who have been working towards the goal of replacing animals in product or ingredient safety testing. Since its inception in 2012, the Lush Prize has distributed almost £2 million. Prizes are awarded for developments in five strategic areas: Science; Lobbying; Training; Public Awareness; and Young Researchers. In 2015, the judges also awarded a Black Box prize for the development of the skin sensitisation Adverse Outcome Pathway and its associated in vitro assays. The Science Prize is awarded to researchers whose work the judging panel believe to have made the most significant contribution, in the preceding year, to the replacement of animal testing. This 2018 Science Background paper outlines the research projects that were presented to the Prize judges as potential candidates for the 2018 Lush Science Prize award. To obtain an overview of developments in the field of animal replacement in toxicity research, recent work by the relevant scientific institutions and projects in this area, including the OECD, CAAT, ECVAM, UK NC3Rs, US Tox21 Programme, the ToxCast programme and EU-ToxRisk, was reviewed. Recent developments in toxicity testing research were investigated by searching the relevant literature. Abstracts from conferences focusing on animal replacement in toxicity testing that were held in the preceding 12 months, were also analysed, including those from the 2017 10th World Congress on Alternatives and Animals in the Life Sciences and the 2018 Society of Toxicology annual conference.


2002 ◽  
Vol 68 (12) ◽  
pp. 6202-6209 ◽  
Author(s):  
Xinsheng Zhou ◽  
Harry K. Kaya ◽  
Kurt Heungens ◽  
Heidi Goodrich-Blair

ABSTRACT The production of an ant-deterrent factor(s) (ADF) by Xenorhabdus nematophila and Photorhabdus luminescens, the symbiotic bacteria of the nematodes Steinernema carpocapsae and Heterorhabditis bacteriophora, respectively, was examined. In addition to an in vivo assay in which bacteria were tested for their ability to produce ADF within insect cadavers (M.E. Baur, H. K. Kaya, and D. R. Strong, Biol. Control 12:231-236, 1998), an in vitro microtiter dish assay was developed to monitor ADF activity produced by bacteria grown in cultures. Using these methods, we show that ADF activity is present in the supernatants of bacterial cultures, is filterable, heat stable, and acid sensitive, and passes through a 10-kDa-pore-size membrane. Thus, ADF appears to be comprised of a small, extracellular, and possibly nonproteinaceous compound(s). The amount of ADF repellency detected depends on the ant species being tested, the sucrose concentration (in vitro assays), and the strain, form, and age of the ADF-producing bacteria. These findings demonstrate that the symbiotic bacteria of some species of entomopathogenic nematodes produce a compound(s) that deters scavengers such as ants and thus could protect nematodes from being eaten during reproduction within insect cadavers.


1982 ◽  
Vol 45 (13) ◽  
pp. 1248-1256 ◽  
Author(s):  
HAROLD E. SWAISGOOD ◽  
GEORGE L. CATIGNANI

Effects of processing on protein structure and its nutritional consequences, and progress towards development of more rapid in vitro assays of nutritional quality are reviewed. Heat and/or alkali processing of proteins initiates Maillard and carbonylamine reactions, causes β-elimination of cystinyl and substituted seryl and threonyl residues, and causes racemization of certain residues. Depending on the extent of these reactions, as determined by the severity of processing conditions, resulting changes may adversely affect bioavailability. Chemical methods for assaying quality have been developed such as the “Chemical Score,” which is based on amino acid analysis of acid hydrolysates, and methods for determining available lysine by reaction with FDNB. Recently a more rapid fluorometric method for measuring available lysine based on reaction with o-phthalaldehyde and mercaptoethanol was developed. Progress is also being made toward improvement of amino acid scores by replacing acid hydrolysis with total enzymic hydrolysis, which should be sensitive to chemical modifications of residues that are eliminated by acid hydrolysis. Reactors containing combinations of immobilized proteinases and peptidases are being characterized for this purpose. Some improvement of amino acid scores is also afforded by adjustments for protein digestibility. Studies of model digestive systems composed of immobilized gastric, pancreatic and intestinal mucosal proteinases and peptidases indicate that such systems may provide parameters reflecting bioavailability.


1979 ◽  
Vol 41 (03) ◽  
pp. 576-582
Author(s):  
A R Pomeroy

SummaryThe limitations of currently used in vitro assays of heparin have demonstrated the need for an in vivo method suitable for routine use.The in vivo method which is described in this paper uses, for each heparin preparation, four groups of five mice which are injected intravenously with heparin according to a “2 and 2 dose assay” procedure. The method is relatively rapid, requiring 3 to 4 hours to test five heparin preparations against a standard preparation of heparin. Levels of accuracy and precision acceptable for the requirements of the British Pharmacopoeia are obtained by combining the results of 3 to 4 assays of a heparin preparation.The similarity of results obtained the in vivo method and the in vitro method of the British Pharmacopoeia for heparin preparations of lung and mucosal origin validates this in vivo method and, conversely, demonstrates that the in vitro method of the British Pharmacopoeia gives a reliable estimation of the in vivo activity of heparin.


1975 ◽  
Vol 33 (03) ◽  
pp. 617-631 ◽  
Author(s):  
H. S Kingdon ◽  
R. L Lundblad ◽  
J. J Veltkamp ◽  
D. L Aronson

SummaryFactor IX concentrates manufactured from human plasma and intended for therapeutic infusion in man have been suspected for some time of being potentially thrombogenic. In the current studies, assays were carried out in vitro and in vivo for potentially thrombogenic materials. It was possible to rank the various materials tested according to the amount of thrombogenic material detected. For concentrates not containing heparin, there was substantial agreement between the in vivo and in vitro assays, with a coefficient of correlation of 0.77. There was no correlation between the assays for thrombogenicity and the antithrombin III content. We conclude that many presently available concentrates of Factor IX contain substantial amounts of potentially thrombogenic enzymes, and that this fact must be considered in arriving at the decision whether or not to use them therapeutically.


2018 ◽  
Vol 21 (3) ◽  
pp. 215-221
Author(s):  
Haroon Khan ◽  
Muhammad Zafar ◽  
Helena Den-Haan ◽  
Horacio Perez-Sanchez ◽  
Mohammad Amjad Kamal

Aim and Objective: Lipoxygenase (LOX) enzymes play an important role in the pathophysiology of several inflammatory and allergic diseases including bronchial asthma, allergic rhinitis, atopic dermatitis, allergic conjunctivitis, rheumatoid arthritis and chronic obstructive pulmonary disease. Inhibitors of the LOX are believed to be an ideal approach in the treatment of diseases caused by its over-expression. In this regard, several synthetic and natural agents are under investigation worldwide. Alkaloids are the most thoroughly investigated class of natural compounds with outstanding past in clinically useful drugs. In this article, we have discussed various alkaloids of plant origin that have already shown lipoxygenase inhibition in-vitro with possible correlation in in silico studies. Materials and Methods: Molecular docking studies were performed using MOE (Molecular Operating Environment) software. Among the ten reported LOX alkaloids inhibitors, derived from plant, compounds 4, 2, 3 and 1 showed excellent docking scores and receptor sensitivity. Result and Conclusion: These compounds already exhibited in vitro lipoxygenase inhibition and the MOE results strongly correlated with the experimental results. On the basis of these in vitro assays and computer aided results, we suggest that these compounds need further detail in vivo studies and clinical trial for the discovery of new more effective and safe lipoxygenase inhibitors. In conclusion, these results might be useful in the design of new and potential lipoxygenase (LOX) inhibitors.


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