PubMed Health⌕ Search

Biomedical subjects

M J Sekellick

Publications and source records attributed to M J Sekellick.

44 records · Page 3Linked to original sources
PubMed1977

Defective interfering particles with covalently linked [+/-]RNA induce interferon.

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 double-stranded RNA presumed to form, at least in part, on entry into the cell is thought to induce interferon synthesis. Conventional [-]RNA DI particles with the same polypeptide composition as [+/-]RNA DI particles fail to induce interferon.

Antibodies, Viral↗
PubMed1971

Interferon action: inhibition of vesicular stomatitis virus RNA synthesis induced by virion-bound polymerase.

The particle-bound RNA polymerase activity of vesicular stomatitis virus (VSV) can be demonstrated in vivo. Linear synthesis of viral RNA persists for 5 to 6 hours at 34 degrees C in infected monolayers of chick embryo cells treated with cycloheximide and actinomycin D to block synthesis of protein and cell-specific RNA. At least 55 percent of the RNA made under these conditions is complementary to virion RNA. RNA synthesis mediated by VSV polymerase activity is inhibited in cells first treated with chick-derived interferon or polyriboinosinate* polyribocytidylate, but not by mouse interferon. The RNA product of VSV polymerase activity is present throughout the cytoplasm, and its synthesis is inhibited by the interferon system, as judged by autoradiographs that show the physical distribution, in cells, of RNA produced by virion polymerase in the absence of translation-a demonstration of the transcription product of the viral genome.

Animals↗
PubMedDate not supplied

Interferon modulation of Marek's disease virus genome expression in chicken cell lines.

Lines of chicken lymphoblastoid cells were established from local lesions induced by simultaneous injection of Marek's disease virus and various stimulants of T-cell activation. Lines developed with regular medium had relatively high mean rates of spontaneous expression of viral internal antigen (6.2%). In contrast, lines developed and maintained with conditioned medium generated by mixed-lymphocyte reaction had a 62-fold reduction in the mean rate of viral internal antigen expression (0.1%). The expression rate could be modulated by the removal or re-addition of conditioned medium to the growth medium. Down regulation involved proteins classified as immediate-early (a 14-kDa polypeptide), early (a 38-kDa phosphoprotein), and late (glycoprotein B homologue) antigens, indicating that the block is very early in virus replication. Once initiated in a given cell, replication apparently proceeded unimpeded. Interferon was determined to be largely responsible for the suppressive activity of the conditioned medium, although involvement of other cytokines could not be ruled out. Also, chicken interferon from other sources, including recombinant interferon, was able to similarly suppress viral antigen expression.

Animals↗