PubMed Health⌕ Search

Biomedical subjects

V E Vengris

Publications and source records attributed to V E Vengris.

11 recordsLinked to original sources

Uptake and fate of water-soluble, nondegradable polymers with antiviral activity in cells and animals.

Poly(9-vinyladenine) and poly(1-vinyluracil) which are nondegradable, soluble polymers are taken up partially by mammalian cells grown in culture. The polymers remain associated with cells for several generations. In mice, after ip application, polymers slowly accumulate in liver, spleen, and thymus and remain there for as long as a month. Thus, these polymers which suppress the replication of murine leukemia viruses also accumulate in organs where the virus replicates. However, their antiviral activity does not reflect the amount of polymer found in these animal tissues. We propose that the polymers are gradually segregated into a group of cells or into subcellular organelles away from primary sites of virus replication. The results suggest that for a directly acting polymeric drug, a half-life over 24 h is without advantage.

Adenine↗

The role of cell membrane in the antiviral effect of interferon.

The mechanism of interferon action in human fibroblasts has been studied by use of both antisera to human fibroblast interferon and the antisera to the surface of human fibroblast cell. The anti-interferon serum completely neutralized the antiviral effect of human fibroblast interferon. Interferon antiserum prevented the intracellular antiviral state from developing when added to the medium of the cells in which interferon synthesis had already been induced by poly (I-C). This suggests that development of the antiviral state involves interferon interaction with the external part of the producing cell. Treatment with the serum directed against the surface of human fibroblast cells failed to inhibit the antiviral activity of human interferon in these cells. In addition, the effect of gangliosides on the antiviral activity of human interferon was studied and it was found that human interferon binds to gangliosides and that this interaction leads to inactivation of the antiviral effect of interferon. Pretreatment of human fibroblasts with gangliosides had no effect on the sensitivity of these cells to exogenous interferon.

Biological Transport, Active↗

Lead poisoning in chickens and the effect of lead on interferon and antibody production.

The effect of aqueous lead acetate given per os to chickens for 35 consecutive days and the effect of lead on interferon and antibody production was investigated. Chickens were found to tolerate levels of lead as high as 160 mg/kg/day without exhibiting clinical signs or hematological changes in spite of very high levels of lead in the blood (6.2 ppm). It is apparent from these findings that chickens are more resistant to lead poisoning than humans, horses, dogs and wild fowl such as ducks. Subclinical lead doses did not affect interferon induction in response to statolon and Newcastle Disease virus (NDV)-B(1). Interferon concentrations and duration in serum were markedly decreased in chickens which received lead at the 320 mg/kg level. Long time lead exposure had no marked effect on antibody production to NDV in chickens. No consistent correlation was observed between blood lead concentration and antibody titer. The results of these studies indicate that long term subclinical lead intake suppresses neither interferon nor antibody production in chickens.

Acetates↗

Swine interferon. I. Induction in porcine cell cultures with viral and synthetic inducers.

The production of interferon by porcine kidney (PK(15)) cell culture in response to viral and synthetic inducers was studied. The inducers used included a synthetic double-stranded polyribonucleotide, polyriboinosinic-polyribocytidylic acid (Poly I:C), swine influenza virus and three strains of pseudorabies virus. Following exposure to these inducers cell culture fluids were examined for interferon by the plaque-reduction method. The Poly I:C and the swine influenza virus induced production of interferon by PK(15) cell cultures, whereas, all three strains of pseudorabies virus at the two concentrations tested failed to induce production of interferon in vitro. The antiviral substance produced in PK(15) cells was identified as an interferon because it was pH stable, non-dialyzable, sensitive to trypsin, non-sedimentable, relatively heat stable, host-species specific and it possessed broad-spectrum antiviral activity. The latter was demonstrated by inhibition of vesicular stomatitis, vaccinia and pseudorabies viruses. Differences in interferon activity against the different viruses were observed.

Animals↗

Swine interferon. II. Induction in pigs with viral and synthetic inducers.

The production of interferon by pigs in response to viral and synthetic inducers was studied. The inducers used included polyriboinosinic-polyribocytidylic acid (Poly I:C), swine influenza virus and pseudorabies virus. Following intravenous inoculation of pigs with the inducers, sera were examined for interferon by the plaque-reduction method in porcine kidney (PK(15)) cell cultures using vesicular stomatitis virus as the challenge inoculum. It was shown that pigs can produce interferon in response to each of these inducers. The pseudorabies virus used in this investigation was found to be a better interferon inducer than the swine influenza virus. The interferon produced in pigs was identified as an interferon because it was pH stable, non-dialyzable, sensitive to trypsin, non-sedimentable and possessed broad-spectrum antiviral activity as well as host-species specificity.

Animals↗

A micro-passive hemagglutination test for the rapid detection of antibodies to infectious bovine rhinotracheitis virus.

Serum antibodies to infectious bovine rhinotracheitis virus are most commonly detected using the serum-virus-neutralization test, a time-consuming and expensive procedure. A passive hemagglutination test was developed for the rapid detection of antibodies using the Microtiter System. Two cloned strains of the virus were used in the investigation, namely the BF strain and the Los Angeles strain. Erythrocytes from several species were used. The best results were obtained using the Los Angeles strain of virus adsorbed to sheep cells treated with formalin and tannic acid. Sera from field cases of the disease as well as hyperimmune bovine and rabbit sera were tested using both the micro-passive hemagglutination test and the standard plaque-neutralization procedures. Comparable titers were obtained in the two tests. The micro-passive hemagglutination test is rapid, accurate and economical.

Animals↗