Surgery of the Anus, Rectum and Colon

WHEN the importance of the thymus to immunological development was discovered in the early 1960's it was appreciated that certain thymic functions may be mediated by humoral factors or hormones. A number of different peptides have been extracted from thymic tissue and there is a large, often controversial, literature dealing with their effects and possible role in T-lymphocyte development. Modern techniques of molecular biology have provided pure preparations of some of the putative hormones and in several cases they have been both sequenced and synthesised. Such developments should help to clarify the role of these factors and a set of review articles on the present "state-of-the-art" could be considered to be timely. Following a brief fatherly introduction by RA Good there is a rather lengthy but critical analysis by Stutman of the possible roles for thymic hormones in T cell differentiation. An important aspect of this review is the attention paid to difficulties of interpretation which result from the choice of system for hormone assay. Clearly a fundamental problem in this field remains-how do we decide whether or not a particular thymic hormone assay is relevant to the physiological role of that hormone? The next chapter deals with the relationship between FTS (facteur thymique serique, recently renamed thymulin) and T cell activation, in particular the growth of interleukin-2 producing T cells. Then follows a chapter on the effects of various thymic hormones on human lymphocytes in vitro. a chapter on the structure and biology of the thymosin peptides and a chapter dealing with similar aspects of thymulin. The book concludes with a chapter on the evaluation of some thymic hormone levels in serum with respect to age and diseases and two chapters on therapeutic adventures with thymic hormones mainly in various immunodeficiency states. Some parts of the book will be of interest to students of immunology. For those with a more general interest in the subject there is an unfortunate imbalance in that some hormones are dealt with in considerable detail whereas others such as Thymic Humoral Factor and Thymopoietins are treated in a very sketchy manner. The clinician looking for guidance in the therapeutic use of thymic hormones will be disappointed. IT is just four years since the fourth edition of this classic was enthusiastically welcomed in these columns. This new edition is, remarkably, even better. Many of the illustrations have been redrawn and the reproduction of others is …