112 Book reviews

Interferon 7. I. Gresser, Ed. (Pp. 2 I I ; £I6.OO.) Academic Press Ltd., London, 1986.

Those who have followed the evolving interferon saga in recent years will be familiar with the series of annual volumes edited by Ion Gresser, now joined by a small group of eminent interferonologists. Each volume has addressed various scientific issues directly or indirectly related to the interferon system. Interferons are an interesting family of cytokines which probably do a lot more than simply respond to the crisis of an acute virus infection. Many scientists from very varied backgrounds have studied aspects of the interferon system and Gresser calls upon them to write from a personal standpoint. Each review tends therefore to teach the background to what may be an entirely new subject. The reviews are usually written or edited in such a way as to be quite digestible to the general medical reader. In the current volume, we can learn about manufacturing genes, about histocompatibility antigens, about cytokines, about macrophage activation, about oncogenes and cell phenotype reversal and the effects of interferon in AIDS.

The chapter by Edge and colleagues from ICI is particularly interesting. It explains the methods and problems in manufacturing genes by stringing nucleotides together on a solid-phase polymer. Such techniques allow the construction of analogues which can then be tested in various antiviral and immune assays, thereby allowing true structure-function analyses to be performed. The conformation of the interferon molecule and one of two disulphide bonds are crucial to antiviral activity which depends on binding to a complex receptor. One as yet unfulfilled hope is that artificial interferons with antiviral but without toxic properties could be made by use of these techniques.

Perhaps one of the fundamental properties of interferons (particularly gamma interferon) is to enhance the expression of histocompatibility antigens. Rosa and colleagues summarise the literature since the first observations in 1973. It may be that chronic production of interferon in autoimmune diseases and the occasional development of autoimmune thyroid disease in treated patients may result from this property of interferon. It appears that synthesis of proteins of class I MHC genes can be induced de novo by alpha interferon, but that class II MHC cannot be induced at all by gamma interferon in cells which do not constitutively express either.

It will not come as a surprise that there are many hormone-like messengers produced by immunologically active cells. If they are of the same complexity as interferons, we have a huge amount to discover. Wallach reviews the current limited knowledge about tumour necrosis factor, produced by macrophages in response to exactly the same molecules that induce interferons, and about lymphotoxin produced by lymphocytes. Production of these is enhanced by interferons. They have myriad functions in various systems and it seems likely that many hypotheses will soon be generated to define and explain roles that each of these molecules play. Macrophage function is particularly enhanced by gamma interferon. Nathan discusses this phenomenon in relation to the production of molecular oxygen, thought to be a key step in microbial killing, and to the production of neopterin which seems to have absolutely no function at all!

Three articles deal with the anti-tumour properties of the interferons. Two of them have, theoretically, in vitro properties, namely reversion of malignant phenotype with prolonged incubation of turnout cells with interferon through many cell cycles; and the regulation of oncogenes, short DNA sequences in eukaryocytic cells analogous to sequences in oncornaviruses. The final chapter is a personal reflection by Krown on the AIDS epidemic and, in particular, the treatment of Kaposi's sarcoma-with interferon. Of these three chapters, only the last would be of immediate interest to the

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practising infectious diseases physician and is already a little out-of-date. T h e idea that we all may carry retroviruses and oncogenes around may, however, provoke some consideration.

As usual, the book is well produced, the text well edited and even complex concepts made digestible. Unless you are working in the field, it may seem that the subject mat ter is rather abstruse. I f you feel stuck in a rut, however, bored by antibiotics, staphylococcal infections and hepatitis, this inexpensive book could open your eyes to a completely new world!

Geoffrey Scott