Stimulation by isoprinosine of the antiviral effect of interferon]

With a single dose of interferon, isoprinosine greatly enhances the antiviral protection of Mice against the lethal effect of encephalomyocarditis virus (100 LD 50).     

Suppression of graft-versus-host reaction by phytohemagglutinin

Zusammenfassung Mit Phytohämagglutinin behandelte Milzzellen erwachsener Mäuse, übertragen auf neugeborene Balb/c-Mäuse, lösen die erwartete « Runt-disease » nicht aus. Versuche mit Milzzellsuspensionen werden diskutiert.

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This investigation was supported by U.S. Atomic Energy Commission, contracts Nos. RLO-1927-26 and AT (45-1)-581.     

Increase of interferon antiviral activity by exogenous cyclic adenosine-3':5'-monophosphate (cAMP).

Some effects of cAMP on replication of Semliki Forest Virus in chick embryo fibroblast cell cultures are described. Depending on concentration, the incorporation of [3H]-uridine into viral RNA or the formation of plaque-forming units is inhibited; the highest concentration tested was 8 mM. Cyclic AMP has an effect of its own and increases the Interferon action in the lower concentration ranges of Interferon (up to 1 unit/ml). The effect of cyclic AMP is fast, needs no induction and is also visible in late phases of viral replication. However, these experiments do not establish a causal relation between cAMP and Interferon.     

Suppression of phytohemagglutinin induced splenocyte proliferation during concurrent infection withEimeria nieschulzi andNippostrongylus brasiliensis

Summary Results suggest that infection withEimeria nieschulzi (Protozoa) interferes with splenocyte proliferation induced by infection withNippostrongylus brasiliensis (Nematoda).This study was supported by NIH MBRS Grant RR08012-15.     

Increase of interferon antiviral activity by exogenous cyclic adenosine-3′∶5′-monophosphate (cAMP)

Summary Some effects of cAMP on replication of Semliki Forest Virus in chick embryo fibroblast cell cultures are described. Depending on concentration, the incorporation of [³H]-uridine into viral RNA or the formation of plaqueforming units is inhibited; the highest concentration tested was 8 mM. Cyclic AMP has an effect of its own and increases the Interferon action in the lower concentration ranges of Interferon (up to 1 unit/ml). The effect of cyclic AMP is fast, needs no induction and is also visible in late phases of viral replication. However, these experiments do not establish a causal relation between cAMP and Interferon.Work supported by the Swiss National Science Foundation, grants 3.1050 and 3.540.     

Reversible inhibition of embryonic mitosis by phytohemagglutinin fromPhaseolus vulgaris

Zusammenfassung Phytohämagglutinin hemmt die Furchungsteilung, im Gegensatz zu differenzierten Geweben, bei denen es als Mitoseaktivator wirkt. Wenn die Eier ausgewaschen werden, läuft die Entwicklung normal weiter.     

Suppression of phytohemagglutinin induced splenocyte proliferation during concurrent infection with Eimeria nieschulzi and Nippostrongylus brasiliensis

Results suggest that infection with Eimeria nieschulzi (Protozoa) interferes with splenocyte proliferation induced by infection with Nippostrongylus brasiliensis (Nematoda).     

Cellular fusion induced in vitro by the mouse scrapie agent]

A method is described to demonstrate and measure the cell-fusion in vitro induced by viruses. This technique has been established using Sendai virus. It has been used to study the fusing ability of the Scrapie agent which is responsible of a slowly progressing spongiform encephalopathy in Mice. In Vero cells, the Scrapie agent induces a fusion which appears slowly and remains moderate. This test can help to detect the human spongiform encephalopathies.     

Effect of sodium butyrate on the interferon sensitivity of normal or cells transformed by murine sarcoma virus]

Sodium butyrate enhances the sensitivity of MSV transformed murine cells to interferon, but does not influence the response of normal cells. Sodium butyrate might act in transformed cells by restoring the different elements of the cytoskeletal system.