Philip I. Marcus

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Avian influenza virus (AIV) A/turkey/Oregon/71-SEPRL (TK/OR/71-SEPRL) (H7N3) encodes a full-length NS1 protein and is a weak inducer of interferon (IFN). A variant, TK/OR/71-delNS1 (H7N3), produces a truncated NS1 protein and is a strong inducer of IFN. These otherwise genetically related variants differ 20-fold in their capacities to induce IFN in primary(More)
Infectious bronchitis virus (IBV) causes an economically important respiratory disease in poultry worldwide. Previous studies have shown that CD8(+) cytotoxic T lymphocytes (CTL) are critical in controlling acute IBV infection, but the role of innate immunity is unknown. This study describes the in vitro and in vivo anti-IBV activity of natural spleen(More)
The effects of x-irradiation have been quantitatively studied on single cells of a human cervical carcinoma (HeLa) under conditions such that 100 per cent of the unirradiated cells reproduce in isolation to form macroscopic colonies. This technique eliminates complexities due to interactions of members of large cell populations. Survival of single cells(More)
The studies chronicled in this chapter were chosen largely because they contained data amenable to the quantitative analysis of interferon induction dose-response curves and the IFP activity they represented. The interpretation of the data was predicated on the assumption that a single molecule of dsRNA, when properly introduced into a cell, either as a(More)
The dynamic changes in the temporal appearance and quantity of a new class of influenza virus, noninfectious cell-killing particles (niCKP), were compared to defective interfering particles (DIP). After a single high-multiplicity passage in MDCK cells of an egg-derived stock that lacked detectable niCKP or DIP, both classes of particles appeared in large(More)
We have expressed a cDNA for virus-induced chick interferon in Escherichia coli. The product, a 19-kDa protein lacking the signal peptide, was purified to homogeneity from the bacterial inclusion bodies. Proteins in the insoluble fraction of bacterial lysates were dissolved in guanidine hydrochloride and subjected to chromatography on Q-Sepharose and MonoS(More)
A gene encoding chicken interferon (ChIFN) was cloned from a cDNA library made from primary chick embryo cells that had been "aged" in vitro so as to produce copious amounts of IFN upon induction. The coding region is predicted to produce a signal peptide of 31 amino acids and a mature protein of 162 amino acids with a molecular weight of 18,957. There are(More)
Defective interfering (DI) particles of vesicular stomatitis virus which contain covalently linked complementary [+]message and [-]anti-message RNA as a single-stranded ribonucleoprotein complex within the particle, are extremely efficient inducers of interferon. A single particle can induce a quantum yield of interferon. A single molecule of(More)