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Biomedical subjects

C E Buckler

Publications and source records attributed to C E Buckler.

At least 37 records · Page 2Linked to original sources

Variation in the number of copies and in the genomic organization of ecotropic murine leukemia virus proviral sequences in sublines of AKR mice.

DNAs isolated from individual mice of four AKR sublines (AKR/J, AKR/N, AKR/Cum, and AKR/Boy) were examined by hybridization of electrophoretically separated restriction enzyme fragments to a 500-base pair, 32P-labeled probe specific for env sequences of ecotropic murine leukemia virus. Variation in the number of proviral DNA copies and in their genomic organization, as reflected by the location of restriction enzyme sites in flanking cellular sequences, was observed both between and within AKR sublines. Evidence is presented for the continual acquisition of new proviruses in the four sublines studied. The ecotropic proviral DNA copies present in the four AKR sublines can be related to their genealogy; each subline contains two or three copies of proviral DNA in common with other sublines and from one to six unique ecotropic proviruses. Overall, a new copy appears about every 12 generations of inbreeding. Some of the unique proviral DNA copies contain internal alterations, as reflected by restriction enzyme maps that differ from those of prototype ecotropic proviruses.

Animals↗

Production of human lymphoblastoid interferon by Namalva cells.

Optimum conditions for growth and interferon production by a human lymphoblastoid cell line, Namalva, have been studied. Adaptation to large-scale production is possible utilizing either Sendai virus or Newcastle disease virus. Priming of cultures before induction is unnecessary. The interferon produced has properties similar to human leukocyte interferon. The production of lymphoblastoid interferon per cell is increased two- to fourfold after dilution with serum-free medium of a saturation-density culture of Namalva induced with Newcastle disease virus. Maximum interferon yields were obtained 27 h after the addition of virus, using cultures diluted to 4 X 10(5) to 9 X 10(5) cells per ml. The presence of glutamine in the dilution medium was required for maximum interferon production. Newcastle disease virus appeared to inhibit the rates of RNA and protein synthesis more effectively in the diluted cultures.

Animals↗

Human lymphoblastoid interferon. Large scale production and partial purification.

Human lymphoblastoid interferon was produced on an 800-liter scale (2.6 X 10(9) units) by induction of Namalva cells with Newcastle disease virus, strain B1. The interferon was partially purified by anti-leukocyte interferon affinity chromatography, sulfopropyl Sephadex ion exchange chromatography, isoelectric focusing, and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Recovery of interferon after gel electrophoresis varied from 11 to 33% based on the original crude material, with about 35,000-fold purification. The gel electrophoresis resolved the antiviral activity into two components with apparent molecular weights of 18,000 and 22,000; treatment with glycosidases resulted in all the activity being associated with the lower molecular weight species. Interferon activity could be completely (85 to 113%) recovered from the gels by elution into a buffer containing sodium dodecyl sulfate. The presence of sodium dodecyl sulfate did not appear to affect the assay of interferon. The protein could also be completely (75 to 106%) eluted from gels stained with coomassie blue, again with no loss in activity.

Cell Line↗

A modified polyriboinosinic-polyribocytidylic acid complex that induces interferon in primates.

A comlex of polyriboinosinic-polyribocytidylic acid (poly I-poly C) with poly-L-lysine and carboxymethylcellulose has been prepared. This complex is five to 10 times as resistant to hydrolysis by primate serum as the parent poly I-poly C. It has a thermal denaturation temperature about 40 C higher than that of poly I-poly C. The complex induces significant levels of serum interferon in monkeys and chimpanzees under conditions in which poly I-poly C itself induces no interferon.

Animals↗

Chlorite-oxidized amylose as an adjuvant for interferon production.

Chlorite-oxidized amylose (COAM), when given intraperitoneally to mice and to cats, increased the titer of serum interferon subsequently induced by polyinosinic.polycytidylic acid (In.Cn). Increases ranged from 6- to 100-fold. Maximal effect was observed when COAM was given 3 h prior to In.Cn. COAM given intravenously prior to Newcastle disease virus also significantly increased serum interferon titers.

Adjuvants, Immunologic↗

Induction of interferon by preparations of synthetic single-stranded RNA.

A study was undertaken to help determine whether synthetic nonbase-paired, single-stranded RNA as well as synthetic base-paired, double-stranded RNA could induce interferon. Synthetic polyriboinosinic acid and polyribocytidylic acid induced interferon and interferon-like resistance in several different cell culture systems. However, in the intact rabbit only the most active preparations of single-stranded RNA induced circulating interferon when injected intravenously. The induced interferon and antiviral effect in tissue culture and animals was shown to have characteristics of the interferon system. Contamination of the single-stranded synthetic RNA materials by small amounts of base-paired, double-stranded RNA was ruled out by failure to find sufficient heterologous nucleic acid bases by differential activities of single-stranded and double-stranded RNA's in different cell systems and by failure to detect double-stranded RNA in poly-rI upon chromatography on benzoylated DEAE-cellulose.

Animals↗