Abelson murine leukaemia virus transformation involves loss of epidermal growth factor-binding sites.

Malignant transformation by mammalian RNA sarcoma viruses has previously been shown to involve a reduction in receptor sites for a well characterized 6,000-molecular weight (MW) growth-promoting substance, designated epidermal growth factor (EGF). Although Abelson murine leukaemia virus (AbLV) resembles sarcoma viruses in its ability to transform embryo fibroblasts in cell culture, AbLV induces a rapid B-cell lymphoid leukaemia rather than fibrosarcomas in vivo. The major translational product of AbLV is a highly phosphorylated polyprotein of MW 120,000 which exhibits an associated tyrosine-specific protein kinase activity and probable transforming function.

Studies on the attachment of herpes simplex virus. Effect of trypsin treatment.

The adsorption of herpes simplex virus (HSV) to monolayers of trypsinized and mock-treated GMK-AH1 cells was studied by means of a microplaque technique. Plaque formation was nearly abolished for c:a 20 minutes and full sensitivity regained at 6--8 hours post trypsinization. The return of sensitivity to HSV was inhibited by cycloheximide and incubation at 4 degrees C.

Studies on glycopeptides of Herpes simplex virus infected cells.

Trypsinates from HSV infected cells, radioactively labeled with glucosamine and galactose were further digested by pronase. The digests were subjected to gel filtration, and it was shown that some of the eluted material consisted of saccharides, highly devoid of residual peptide. This material eluted between linear dextran markers of 19,000 and 3000 daltons.

Hemolysis-in-gel and neutralization tests for determination of antibodies to mumps virus.

A hemolysis-in-gel test for the demonstration of antibodies to mumps virus is described. The results were compared with those of neutralization tests using a modified microtechnique. In the neutralization test viral replication was demonstrated by the hemadsorption of guinea pig erythrocytes, the visibility of which could be further enhanced by the use of o-tolidine.

Variations in lipid composition and sound velocity in melon from the North Atlantic Pilot whale, globicephala melaena melaena.

Nonpolar lipids and sound velocity at different distances from the skin surface within a sample of pilot whale melon were studied. Thin layer chromatography, sensitive radioisotopic methods, and an ultrasonic echo scanner were used. Wax esters had a maximum concentration at 11-12 cm from the skin surface.

Purification of virions and nucleocapsids of herpes simplex virus by means of metrizamide and sodium metrizoate gradients.

The generation of density gradients for ultracentrifuging by freezing and thawing was applied to formation of linear density gradients with sodium metrizoate and metrizamide. Using these gradient materials simple and rapid methods for purification of virions and nucleocapsids of herpes virus were elaborated. Using metrizamide the recovery of infectivity was 10-30 per cent, and the purification of virions measured as reduction of host protein was 1700 times.

Subtyping of herpes simplex virus.

A number of different techniques to be used for the subtyping of herpes simplex virus (HSV) strains were studied. The strains were inoculated on chorio-allantoic membranes of embryonated eggs and on green monkey kidney (GMK) cells in order that the morphology of plaques produced might be observed. They were classified serologically by determination of K-values and inoculated intracerebrally in mice in order that their pathogenicity for mice might be observed.