Replication-deficient adenovirus (Ad) vectors provide an efficient technology for direct DNA delivery to cells both in vitro and in vivo. We have inserted the measles virus nucleoprotein (N) gene under the control of the strong constitutive CMV major IE promoter into an Ad type 5 E1- vector to produce the recombinant virus RAd68. Following infection of human fibroblasts with RAd68 in vitro, recombinant N protein was synthesized as a 60-kDa protein that represented up to 20% total soluble cell protein. Long filamentous structures were produced in both the nucleus and the cytoplasm that were similar in appearance to measles virus nucleocapsids. These "nucleocapsid-like" structures were readily purified by density gradient centrifugation. Murine immunization with RAd68 elicited (i) a humoral immune response to N, (ii) a major histocompatibility complex class I-restricted, antigen-specific cytotoxic T cell response, and (iii) protection against challenge with the measles virus CAM/RB strain in mice. This study demonstrates the capacity of replication-deficient Ad recombinants both to induce and to characterize cell-mediated immune responses.
Over the last three years considerable progress has been made in various areas related to measles virus and infection. A meeting to discuss the currently available data on the molecular biology of measles virus, measles immunology, immunopathology, as well as animal models for measles infection, and to identify studies that need to be carried out towards developing new vaccines was organized jointly by WHO and the U.S. National Institutes of Health and held in Montreux, Switzerland on 20-21 April 1993. This Memorandum summarizes the discussions and recommendations made by the participants.
The biological activity of monoclonal antibodies specific for the hemagglutinin protein of measles virus strain CAM recognizing six epitope groups according to their binding properties to measles virus strain CAM/R401 was investigated in vivo in our rat model of measles encephalitis. When injected intraperitoneally into measles virus-infected suckling rats, some monoclonal antibodies modified the disease process and prevented the necrotizing encephalopathy seen in untreated animals. The analysis of measles virus brain isolates revealed emergence of variants that resisted neutralization with the passively transferred selecting monoclonal antibody but not with other monoclonal antibodies. Monoclonal antibody escape mutants were also isolated in vitro, and their neurovirulence varied in the animal model. Sequence data from the hemagglutinin gene of measles virus localize a major antigenic surface determinant of the hemagglutinin protein between amino acid residues 368 and 396, which may be functionally important for neurovirulence. The data indicate that the interaction of antibodies with the measles virus H protein plays an important role in the selection of neurovirulent variants. These variants have biological properties different from those of the parent CAM virus.
We review entities that have historically been thought to be pseudotumors or mimics of bone tumours. We discuss tumifactive amyloid deposits, the brown tumours of hyperparathyroidism, the various types of cysts that can be seen in bone, Nora lesion, subungual exostosis, haemophilic pseudotumors, non-ossifying fibroma, fibrous dysplasia, osteofibrous dysplasia, Paget disease, tophaceous gout and pseudogout.
The gene encoding the major nucleocapsid, N, protein of measles virus has been inserted into a baculovirus vector under the control of the polyhedrin promoter. Insect cells infected with this recombinant baculovirus synthesize high levels of measles N protein, up to 40% of total soluble cell protein. The recombinant protein is recognized by sera from convalescent patients, vaccinees and patients with subacute sclerosing panencephalitis and thus could form the basis of a simple diagnostic assay. Nucleocapsid-like structures, similar to those found in mammalian cells infected with measles virus, can be observed in both the nucleus and cytoplasm of the infected insect cells. These have many structural features in common with nucleocapsids found in measles virus-infected cells, but are longer (up to 2 microns) and have a lower buoyant density. Measles N protein thus appears to be capable of assembling into nucleocapsid-like structures in the absence of measles virion RNA or other viral proteins.
The sequences of a region of the nucleocapsid protein gene, between nucleotides 1231 and 1686, encoding the C-terminal 151 amino acid residues of the nucleocapsid protein have been determined for 16 strains of measles virus. Analysis of this region showed that it is highly divergent (up to 7.2% divergence in the nucleotide sequence and 10.6% divergence in the amino acid sequence between most distant strains) and that several lineages of measles virus can be found to co-circulate at a given time. Some of the lineages show geographical restriction. The results for measles virus are similar to those reported for other human paramyxoviruses such as mumps virus, parainfluenza type 3 virus and the avian Newcastle disease virus.
Summary Serum antibody titres to eight neurotropic viruses were measured by enzyme immunoassay in 450 psychiatric in-patients and 143 controls. A seasonal variation in schizophrenic births was observed, with a peak incidence between March and April. Both herpes simplex virus and cytomegalovirus antibody titres correlated with age and, when this was controlled for, no significant differences emerged between any patient group and the controls. Mumps antibody titres were significantly lower in patients with mental subnormal and neurosis or personality disorder; measles and rubella antibody titres were lower in male but not female mentally handicapped patients; males had lower antibody titres to mumps, cytomegalovirus and Epstein-Barr virus than females in all groups. A decrease in mumps antibody titres was also found in schizophrenics if the medication factor was excluded. These low antibody titres may indicate an impaired immune response. Thus perinatal or childhood subclinical viral infections of the central nervous system, particularly of mumps, might lead to a range of possible psychiatric outcomes in later life.