Warren R. Stinebring

Patterns of Interferon Appearance in Mice injected with Bacteria or Bacterial Endotoxin.

PREVIOUS work1 has shown that the intravenous injection of large numbers of live Brucella abortus into chickens results in the appearance in the serum of a viral inhibitor with the properties of interferon. Inhibitor reached maximum levels about 12 h after inoculation. It was also reported that large numbers of Newcastle disease virus (NDV) particles produced maximum levels of interferon in chickens about 12 h after intravenous inoculation. Injection of large doses of other gram-positive and -negative bacteria or bacterial endotoxins failed to produce demonstrable inhibitors in the circulation of chickens at 6–8 h.

Influence of Inhibitors of Protein Synthesis on Interferon Formation in Mice.

Abstract The existence of preformed interferon in the tissues of intact animals has been clearly demonstrated by the experiments reported. This was shown by the finding that doses of puromycin or cycloheximide which effectively inhibited protein synthesis did not prevent the appearance of circulating interferon in mice injected with bacterial endotoxin. In contrast, interferon induction by Brucella abortus or NDV was eliminated by blockade of protein synthesis. Further evidence for the presence of preformed interferon in intact mice was provided by experiments in which only cycloheximide was injected. Effective blockade of protein synthesis was accompanied by the appearance in the circulation of significant amounts of a viral inhibitor which was indistinguishable from virus-induced interferon.

Interferon Production in Chickens Injected with Brucella abortus

Intravenous injection of large numbers of live, virulent Brucella abortus in chickens resulted in the appearance in the serum of a viral inhibitor indistinguishable from interferon. Inhibitor was detected as early as 3 hours after inoculation of brucellae and reached a peak between 6 and 12 hours.

Comparison of interferon production in mice by bacterial endotoxin and statolon.

Abstract A comparison has been made of interferon production in mice injected intravenously with Escherichia coli endotoxin or statolon. Similar to previous findings with endotoxin, doses of cycloheximide which effectively blocked protein synthesis did not prevent the appearance of circulating interferon in mice injected with statolon. This finding indicates the existence of this interferon in a preformed state in the intact animal. Mice given two intravenous doses of either endotoxin or statolon, 48 hours apart, showed markedly diminished interferon response to the second injection of only the homologous stimulus. Pretreatment of mice with endotoxin failed to diminish significantly the response to statolon, and prior injection of statolon had no effect on the interferon titer produced with endotoxin. In addition, although endotoxin produced markedly enhanced levels of interferon in mice infected with attenuated tubercle bacilli (BCG), interferon production following different doses of statolon was not significantly different in infected and uninfected mice. These results are interpreted to mean that, although the interferons produced in mice by statolon and endotoxin are both present in a preformed state in the animal and both have similar molecular weights of 90,000, they are released from different cell populations or by different mechanisms.

Hyperreactivity to endotoxin in BCG-treated guinea pigs and its relationship to delayed hypersensitivity.

Summary The development of systemic and cellular reactivity to PPD has an entirely different pattern from that of hyperreactivity to endotoxin in BCG immunized guinea pigs. Hyperreactivity appears not to be related to altered cellular reactivity in contrast to PPD sensitivity or delayed sensitivity to well characterized proteins.

Inhibition of viral replication by interferons with different molecular weights.

Summary No differences were found in the rates at which mouse cells develop resistance to virus challenge after exposure to interferons with markedly different molecular weights (30,000 or 90,000). These interferons were made in L-cell cultures in response to NDV or in intact mice stimulated with E. coli endotoxin or statolon. When kept in contact with interferon, cells showed virtually maximum resistance to virus after 3 to 4 hours of exposure. Exposure to interferon for 1 hour was followed by a gradual increase of resistance of cells to virus infection over the next 23 hours.

[26] General procedures for the induction and production of avian interferons

Publisher Summary This chapter discusses general procedures for the induction and production of avian interferons. Avian interferons may be induced directly in the allantoic fluid of the embryonated egg or in cell cultures produced from whole-embryo digests. The interferon-containing allantoic or culture fluid is then well suited for use as a crude preparation or in further purification schemes. For interferon production in cell cultures, embryo cell cultures are produced by using a standard tissue dissociation method. Newcastle disease virus (NDV) is inactivated by exposure to UV light. The virus is exposed just long enough completely to inactivate its ability to replicate, as monitored by inoculation into eggs or cell cultures. Cell cultures are inoculated with inactivated NDV at a ratio of 10 viral units per cell, determined by plaque assays done prior to inactivation.