A Mammalian Cell Agar-Diffusion Assay for the Detection of Toxic Compounds

Burres, Neal S.; Hunter, Janet; Wright, Amy E.

doi:10.1021/np50063a010

Cited by 7 publications

(3 citation statements)

References 7 publications

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“…Cytotoxicity of the extracts to the murine leukemia cell line P-338 was determined in 96-well tissue culture plates as described by Burres et al (1989). Briefly, P-388 cells (1 x 105 cells ml-) were incubated at 37 C in a humidified atmosphere of 5% CO2-air (v/v) in RPMI 1640 medium, supplemented with 10% horse serum, containing aliquots of the crude extracts.…”

Section: Sample Preparation and Bioassaymentioning

confidence: 99%

Cytotoxin production by a merineLyngbya strain (cyanobacterium) in a large-scale laboratory bioreactor

et al. 1991

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A cytotoxic compound was produced by the marine cyanobacterium Lyngbya sp. Pearl strain in large laboratory-scale batch cultures. Adsorption and fractionation of methanol extracts with reverse phase (C-18) cartridges provided a rapid method for removal of bioassay interference from salts, biopolymers and pigments and concentration of the cytotoxic principles. Cytotoxicity to the murine leukemia cell line P-388 was produced in two cycles coinciding with the initiation of exponential growth and again during the late exponential growth phase. Antiviral activity against influenza virus PR8 was found in extracts prepared from early exponential growth phase cells but antiviral activity was not detected in extracts of mid-log or late-log growth phase cells. These differences in bioactivity suggests that the cytotoxic principles produced during early and late exponential growth may be different compounds. Cytotoxicity assays using murine P-388 leukemia indicates that the semi-pure compound has an IC 50 of < 0.25 jg ml -1 to this cell line. P-388 cytotoxicity in cell extracts increased during the late exponential growth phase and the specific yield was estimated at approximately 0.14 mg g -(dry cells).

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Section: Sample Preparation and Bioassaymentioning

confidence: 99%

Cytotoxin production by a merineLyngbya strain (cyanobacterium) in a large-scale laboratory bioreactor

et al. 1991

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“…This compound was originally isolated from whole dried gorgonians in 1960 15 and later found to exhibit modest in vitro cytotoxicity against fibroblasts, human leukemic cells, and HeLa cells in the anti-cancer drug discovery program at the National Cancer Institute. [16][17][18] CRA dose dependently inhibited the proliferation of C57BL/6-derived T cells triggered by BALB/c-derived DCs, with a significant effect (P Ͻ .01) observed at 2 M and almost complete (Ͼ 95%) inhibition achieved at 5 M ( Figure 1C). We also tested the impact of CRA on OVA-specific CD4 ϩ T cells freshly isolated from the DO11.10 TCR transgenic mice (BALB/c background).…”

Section: Identification Of Immunosuppressive Activities Of Cramentioning

confidence: 99%

Identification of crassin acetate as a new immunosuppressant triggering heme oxygenase-1 expression in dendritic cells

Matsushima

Tanaka

Mizumoto

et al. 2009

Blood

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By screening 720 natural compounds in a standard 2-way allogeneic mixed leukocyte reaction assay, we identified a potent immunosuppressive capacity of crassin acetate (CRA), a coral-derived cembrane diterpenoid. CRA efficiently inhibited allogeneic mixed leukocyte reaction as well as antigen-specific activation of CD4 T cells by bone marrow-derived dendritic cells (DCs). With regard to cellular targets, CRA suppressed not only mitogentriggered T-cell activation, but also lipopolysaccharide-induced DC maturation, indicating dual functionality. Treatment with CRA at nontoxic doses induced heme oxygenase-1 (HO-1) mRNA/protein expression and HO-1 enzymatic activity in DCs, suggesting a unique mechanism of action. In fact, lipopolysaccharideinduced DC maturation was also inhibited by structurally unrelated compounds known to induce HO-1 expression or carbon monoxide (CO) release. Allergic contact hypersensitivity response to oxazolone and oxazolone-induced Langerhans cell migration from epidermis were both prevented almost completely by systemic administration of CRA. Not only do our results support the recent concept that HO-1/CO system negatively regulates immune responses, they also form both conceptual and technical frameworks for a more systematic, largescale drug discovery effort to identify HO-1/ CO-targeted immunosuppressants with dual target specificity. (Blood. 2009;114:64-73)

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“…This assay detects compounds that damage DNA (1), and the construction of Escherichia colt strains lysogenic for a X-lacZ fusion phage has allowed colorimetric quantitation of prophage induction by the appearance of ß-galactosidase, a product of the lacZ gene (2). Other assays involve measuring cytotoxicity in the presence and absence of exogenous DNA (3,4), monitoring topological changes in covalently closed circular DNA (5) or spectral changes in the drug resulting from the interaction (6,7). A recently described hplc assay that uses DNA as an affinity probe may be particularly powerful for identifying DNA-active compounds present in certain complex extracts (8).…”

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A Colorimetric Microassay for the Detection of Agents that Interact with DNA

et al. 1992

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A simple microtiter assay for the detection of compounds that bind DNA is described. Agents that displace methyl green from DNA are detected spectrophotometrically by a decrease in absorbance at 630 nm. The feasibility of using the assay for detecting DNA-active compounds in fermentation extracts was assessed, and the activities of reference compounds in the methyl green assay and an ethidium bromide displacement method were compared.

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A Mammalian Cell Agar-Diffusion Assay for the Detection of Toxic Compounds

Cited by 7 publications

References 7 publications

Cytotoxin production by a merineLyngbya strain (cyanobacterium) in a large-scale laboratory bioreactor

Cytotoxin production by a merineLyngbya strain (cyanobacterium) in a large-scale laboratory bioreactor

Identification of crassin acetate as a new immunosuppressant triggering heme oxygenase-1 expression in dendritic cells

A Colorimetric Microassay for the Detection of Agents that Interact with DNA

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