Chemical modifications of human and murine interferons.

Methods that modify the carbohydrate and peptide portions of human and murine interferons have been described. Such work has helped considerably in our understanding of these fascinating substances. The most powerful of the methods relies on gene manipulation: it has already led, and will lead in the future, to further species with altered biological activities.

Positive interactions between interferon and chemotherapy due to direct tumor action rather than effects on host drug-metabolizing enzymes.

The mechanism of increased antitumor activity when human lymphoblastoid interferon [HuIFN-alpha(Ly)] and the drugs cyclophosphamide and Adriamycin are used in combination on a human tumor xenograft in nude mice has been investigated. HuIFN-alpha(Ly) did not affect hepatic levels of the drug-metabolizing enzymes cytochrome P-450 or the glutathione S-transferases. In contrast, mouse interferon caused significant and differential changes in the isozymic forms of these enzymes.

Analysis and purification of human lymphoblastoid (Namalwa) interferon using a monoclonal antibody.

Highly purified interferon-alpha (IFN-alpha) prepared from a human lymphoblastoid line (Namalwa) was analysed by gel filtration and polyacrylamide gel electrophoresis (PAGE). Gel filtration separated the IFN-alpha into two peaks (A and B). All the components of peak A were retained by a monoclonal antibody (NK2) column, but some of those from peak B were not retained.

Human interferon inhibits the growth of established human breast tumours in the nude mouse.

In this paper we describe a model system for looking at the effects of human interferon, IFN, on an established human tumour. Highly purified human IFN derived from lymphoblastoid cells (HuIFN alpha-Namalwa) strongly inhibited the growth of a human breast cancer growing as a xenograft in nude mice. The effect was dose-dependent, required daily treatment for an optimal effect and was time-dependent, little inhibition being seen before 2 weeks of therapy.