Bücher der Reihe Current Topics in Microbiology and Immunology

In any movement of their life, immune cells, especially T and B lymphocytes, are confronted with an essential choice: to continue their existence or to commit a sort of metabolic suicide that is referred to as apoptosis or programmed cell death.

Thus the phenomenon of has long been a source of fascina variegation among organisms In plants, variegation is most easily recognised as irregulari tion. in pigment patterns on leaves, flowers and seeds, but other ties as leaf or flower form might also show characteristics such In 1588, such a variegation pattern was described in variegation.

Cellular promoters whose E2F sites mediate a link between transcription and proliferation drive genes whose products are required for DNA synthesis and genes that encode regulators of cell growth.

The chicken is a useful model for research into the basic features of immunology because its immune system functions in a way similar to that of human beings and because the chicken embryo is easily accessed experimentally. This book is a collection of comprehen­ sive articles updating chicken embryogenesis and immunology. It is now clear that it is possible to produce transgenic chickens by embryonic stem cell manipulation and transfer into the oocyte. Alternatively, the chick offers us the possibility of producing somatic chimeras by manipulating embryonic cells at the primitive streak or earlier stages. Working with later em­ bryos, we can learn the principles involved in the positioning of organ anlagen such as the limb bud. It is shown in this book that these structures are formed by appropriate cell and tissue arrangements driven by molecular factors. Work on the chicken has contributed substantially to our understanding of basic immunology, including the graft-vs. -host reaction, the clonal reactivity of immunocompetent cells, sepa­ ration of the T and B cell lineages, somatic diversification of the B cell repertoire by immunoglobulin (Ig) class switching, anti­ body diversification, Ig gene conversion, and the origin of the hematopoietic stem cell precursor of lymphoid and myeloid cells. Hematopoietic stem cells emerge successively from sev­ eral embryonic sites such as the yolk sac, the aorta, and the mesentery near the aorta.

Retroviruses arguably belong to the most fascinating of all viruses because of their unusual and highly efficient mode of replication involving reverse transcription and integration of the viral genome and a complex system of transcriptional and post transcriptional regulatory mechanisms.

Similarly, Austria experienced a 5% increase in tuberculosis cases from 1987 to 1991, Ireland a 9% increase from 1988 to 1991, Denmark a 20% increase from 1987 to 1992, and Italy a 27% increase from 1988 to 1992.

Antibiotics have indeed brought unprecedented health benefits, protection from and cure of bacterial diseases during the past 50 years. They are crum bling because we wittingly or unwittingly created selective con ditions for the emergence of superior pathogens that can no longer be controlled by antibiotics.

On occasion, the innate immune system is referred to as the "primitive" immune system. On the contrary, the innate immune system has had time to achieve a level of refinement that is nothing short of dazzling, and a modicum of respect is at long last due.

A workshop on "MOLECULAR ASPECTS OF MYELOID STEM CELL DEVELOPMENT" was held at the Historic Inns in Annapolis, MD during April 30-May 3, with approximately 70 persons attend ing.

Viruses are major pathogens in humans, and in the organisms with which we share this planet. For membrane traffic in parti- lar, viruses have been crucial in providing insights into key cellular fu- tions and the molecular mechanisms underlying these events.

Apoptosis is a regulated, energy-dependent process by which a cell se- destructs. This mechanism of programmed cell death plays an important role in normal development and control of cell numbers in mature a- mals. Apoptosis was initially defined by morphological criteria to describe the distinctive appearance of dying cells that developed nuclear conden- tion, cell shrinkage, and cytoplasmic blebbing. Initiation of the apoptotic process can come from external or internal stimuli and is highly regulated both by molecules that facilitate and by molecules that inhibit the process. Common features of apoptosis include activation of proteases and - cleases, mitochondrial membrane permeabilization, chromatin disruption, and translocation of phosphatidylserine from the inner to the outer s- face of the plasma membrane. Apoptotic cells attract phagocytes that - gulf the apoptotic bodies and prevent tissue damage in the region. Intense investigation of the cell death process has defined many molecular features of the pathway by which regulation and execution can be exploited by pathogens.

Pathogenic bacteria for human and animals have developed sophisticated weapons, termed virulence factors, to ensure their replication and persistence into their hosts. The authors in this volume show a synthesis on how the various host cellular Rho GTPases activities are manipulated by bacteria to fulfil their virulence.

yetwehopethatitwillofferinspirationandorientationtothescientistwho wouldliketoenterthis?eld. To date, many different cells have been described that can suppress + + other cells of the immune system: CD4 CD25 regulatory T cells (Treg), + ? CD4 CD25 regulatory T cells, T regulatory 1 cells (Tr1), T-helper 3 cells + ? (Th3),CD8 CD28 Tcells,NKTcells,aswellastolerogenicdendriticcells. Suppressive CD4 T cells fall at least into two categories. So called natural VI Preface + + CD4 CD25 Tregformpartoftheintra-thymicallyselectedTcellrepertoire andapparentlyconstituteadistinctlineage. Incontrast,"adaptive"regulatory Tcellsareinstructedintheperipherytobecomesuppressivecells,theyform + + amoreheterogeneousgroupincludingCD4 CD25 Treg,Tr1,andTh3cells. As natural Treg are so far the best characterized entity, the ?rst three contributionsofthisvolume(C. Cozzoetal. ,C. -S. Hsiehetal. ,andL.

For a long time the Cinderella of lymphoid malignancies CLL has now become the focus of major interest and an increasing number of investigators from different areas, including genetics, molecular biology, basic and applied immunology are becoming actively engaged in the investigation of CLL.

Hepatitis C virus (HCV), a major causative agent of chronic liver disease, is spread throughout the world and around 170 million people are persistently infected.

It may now be possible to ask how memory cells are generated and to define what signals are required during or after antigenic encounter for a cell to enter the memory cell pool rather than to terminally differentiate into an effector cell.

Although retroviruses have long been associated with a variety of animal diseases, active research in the field of human retroviruses dates from the discovery of human immunodefici ency virus (HIV) in association with acquired immunodefici ency syndrome (AIDS).

They present eleven reviews that cover a wide range of topics, from wound repair and its relationship to regeneration, through systems including lenticular, neural, and musculoskeletal tissues and limbs, to epigenetics and the role of the cell cycle.

PASTAN , and J. ROBERTUS Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3 3 Intracellular Processing - Cleavage and Reduction . . . . . . 1 Cytosolic Activity . . . , diphtheria toxin, Pseudomonas exotoxin and ricin) are among the most toxic substances known.

This book gives a concise review of the known human retroviruses; The book ends with a critical review of recent work suggesting a possible role of still other retroviruses in human disorders including malignancies, autoimmune, or neurologic diseases.

One chapter discusses how intrinsic immunity and viral countermeasures to intrinsic immune effectors drive both pathogen and host evolution, and finally the emerging evidence that DNA damage response proteins restrict infection by DNA viruses is highlighted.

The third and, as of yet, unexplored aspect relates to a means of delivering genes for therapeutic purposes thus overcoming some of the limitations of "conventional" gene therapy.

Marburg and Ebola virus, the two species within the family Filoviridae, are among the most pathogenic agents causing fulminant hemorrhagic fever in humans and nonhuman primates.

FERRARA Vascular Endothelial Growth Factor: Molecular and Biological Aspects . . . . . . . . . . . . . . . . . . . . . . . . . . DIPALMA Structure, Expression and Receptor-Binding Properties of Placenta Growth Factor (PIGF) . . . . . . . . . . . . . . CLAESSON-WELSH Structure and Function of Vascular Endothelial Growth Factor Receptor-I and -2 .

Within the next few years, it was apparent that this and other similar viruses were not polioviruses but were indeed a new group of viruses, viruses that by the mid- 1950s had been found to be commonly associated with pediatric inflammatory heart disease.