Genetically restricted suppressor T-cell clones derived from lepromatous leprosy lesions

Leprosy is a spectral disease in which immune responses to Mycobacterium leprae correlate with the clinical, bacteriological and histopathological manifestations of disease, so study of its pathology provides insights into immunoregulatory mechanisms in man. At the tuberculoid pole, patients have few lesions in the skin which contain rare organisms and are able to mount strong cell-mediated immune responses to M. leprae antigens. In contrast, at the lepromatous pole, patients have disseminated skin lesions containing large numbers of acid-fast bacilli and are selectively unresponsive to antigens of M. leprae. M. leprae-induced suppressor cells derived from peripheral blood have been reported to be active in vitro, yet their in vivo significance has remained unclear. Because the focal point of the immune response to M. leprae is the skin lesion consisting of lymphocytes and macrophages, we have recently developed methods for isolating lymphocytes from skin biopsies of leprosy patients. We report here that two T8 clones derived from lepromatous leprosy skin biopsies, in the presence of lepromin, suppress concanavalin A (Con-A) responses both of peripheral blood mononuclear cells and of T4 clones in an HLA-D (HLA, histocompatibility locus antigen)-restricted manner. Moreover, these T8 clones suppressed responses of HLA-D-matched, but not HLA-D-mismatched antigen-responsive T4 clones to M. leprae antigens, indicating that T-cell suppression is major histocompatibility complex (MHC)-restricted at some level in man.     

The role of the autonomic nervous system in mediating pancreatic endocrine responses to arginine in the calf

Summary The release of insulin which occurred in response to arginine, in the conscious calf, differed from that which occurs in response to glucose in that it was not significantly affected by either adrenergic or muscarinic blocking agents. Release of pancreatic glucagon was reduced by pretreatment with phentolamine.This work was supported by the British Diabetic Association. It is a particular pleasure to acknowledge the skilled assistance provided by Messrs P. M. M. Bircham and G. P. McGregor.     

Bombesin-like immunoreactivity in the pituitary gland

Bombesin has been shown to stimulate release of anterior pituitary hormones both in vivo and in vitro. The aim of this study was to determine whether bombesin-like immunoreactivity could be detected in the human pituitary. Significant concentrations were found in the human anterior gland (4.6 +/- 1.5 pmoles/g), posterior gland (1.5 +/- 0.4 pmoles/g) and stalk (8.1 +/- 0.8 pmoles/g). Significant amounts were also observed in the guinea-pig pituitary. Gel permeation chromatography revealed the presence of 2 major molecular forms of bombesin-like immunoreactivity, one co-eluting with porcine gastrin-releasing peptide and the other with amphibian bombesin.     

Metrial gland and peroxidase activity

Zusammenfassung Mit Hilfe des Mesidintests wurde in der Mucosa, nicht aber in den metrialen Drüsen des trächtigen Rattenuterus eine Peroxydase gefunden.     

Specific immunostaining of CCK cells by use of synthetic fragment antisera

Summary Antibodies to the central fragments 9–20 dodecapeptide sequence of CCK were used for specific immunostaining of the CCK cells of the mammalian gut. The use of high specific antibodies to synthetic fragment, essential when there is a possibility of immunochemical cross reactions between antisera and hormones of similar molecular structure provides the key to increased understanding of the nature and relationships of peptide hormones.Grants from the Medical Research Council and the Volkswagenwerk-Stiftung made the work possible.     

DNA sequence and analysis of human chromosome 18

Chromosome 18 appears to have the lowest gene density of any human chromosome and is one of only three chromosomes for which trisomic individuals survive to term. There are also a number of genetic disorders stemming from chromosome 18 trisomy and aneuploidy. Here we report the finished sequence and gene annotation of human chromosome 18, which will allow a better understanding of the normal and disease biology of this chromosome. Despite the low density of protein-coding genes on chromosome 18, we find that the proportion of non-protein-coding sequences evolutionarily conserved among mammals is close to the genome-wide average. Extending this analysis to the entire human genome, we find that the density of conserved non-protein-coding sequences is largely uncorrelated with gene density. This has important implications for the nature and roles of non-protein-coding sequence elements.     

Intracellular localization of acid phosphatase and aryl sulfatase in rat metrial gland cells

Zusammenfassung Die beiden lysosomalen Fermente (saure Phosphatase und Aryl Sulphatase) wurden mit elektrohistochemischer Technik in den zytoplasmatischen Zellgranula der Glandula myometralis gravider Ratten demonstriert. Die Befunde werden in Beziehung zur heutigen Kenntnis der funktionellen Granulanatur diskutiert.     

Supernova SN 2011fe from an exploding carbon-oxygen white dwarf star

Type Ia supernovae have been used empirically as 'standard candles' to demonstrate the acceleration of the expansion of the Universe even though fundamental details, such as the nature of their progenitor systems and how the stars explode, remain a mystery. There is consensus that a white dwarf star explodes after accreting matter in a binary system, but the secondary body could be anything from a main-sequence star to a red giant, or even another white dwarf. This uncertainty stems from the fact that no recent type Ia supernova has been discovered close enough to Earth to detect the stars before explosion. Here we report early observations of supernova SN 2011fe in the galaxy M101 at a distance from Earth of 6.4 megaparsecs. We find that the exploding star was probably a carbon-oxygen white dwarf, and from the lack of an early shock we conclude that the companion was probably a main-sequence star. Early spectroscopy shows high-velocity oxygen that slows rapidly, on a timescale of hours, and extensive mixing of newly synthesized intermediate-mass elements in the outermost layers of the supernova. A companion paper uses pre-explosion images to rule out luminous red giants and most helium stars as companions to the progenitor.