The serial cultivation of human diploid cell strains.

The limited in vitro lifetime of human diploid cell strains

The discovery that mammalian cells have the ability to synthesize the free radical nitric oxide (NO) has stimulated an extraordinary impetus for scientific research in all the fields of biology and medicine. Since its early description as an endothelial-derived relaxing factor, NO has emerged as a fundamental signaling device regulating virtually every critical cellular function, as well as a potent mediator of cellular damage in a wide range of conditions. Recent evidence indicates that most of the cytotoxicity attributed to NO is rather due to peroxynitrite, produced from the diffusion-controlled reaction between NO and another free radical, the superoxide anion. Peroxynitrite interacts with lipids, DNA, and proteins via direct oxidative reactions or via indirect, radical-mediated mechanisms. These reactions trigger cellular responses ranging from subtle modulations of cell signaling to overwhelming oxidative injury, committing cells to necrosis or apoptosis. In vivo, peroxynitrite generation represents a crucial pathogenic mechanism in conditions such as stroke, myocardial infarction, chronic heart failure, diabetes, circulatory shock, chronic inflammatory diseases, cancer, and neurodegenerative disorders. Hence, novel pharmacological strategies aimed at removing peroxynitrite might represent powerful therapeutic tools in the future. Evidence supporting these novel roles of NO and peroxynitrite is presented in detail in this review.

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Nitric Oxide and Peroxynitrite in Health and Disease

▪ Abstract At the interface between the innate and adaptive immune systems lies the high-output isoform of nitric oxide synthase (NOS2 or iNOS). This remarkable molecular machine requires at least 17 binding reactions to assemble a functional dimer. Sustained catalysis results from the ability of NOS2 to attach calmodulin without dependence on elevated Ca2+. Expression of NOS2 in macrophages is controlled by cytokines and microbial products, primarily by transcriptional induction. NOS2 has been documented in macrophages from human, horse, cow, goat, sheep, rat, mouse, and chicken. Human NOS2 is most readily observed in monocytes or macrophages from patients with infectious or inflammatory diseases. Sustained production of NO endows macrophages with cytostatic or cytotoxic activity against viruses, bacteria, fungi, protozoa, helminths, and tumor cells. The antimicrobial and cytotoxic actions of NO are enhanced by other macrophage products such as acid, glutathione, cysteine, hydrogen peroxide, or superoxid...

Nitric oxide and macrophage function

http://theory.bio.uu.nl/immbio/Marks91.pdf

By-passing immunization: Human antibodies from V-gene libraries displayed on phage

Whereas normal human and monkey cells were susceptible both to intact simian virus 40 (SV40) and to SV40 deoxyribonucleic acid (DNA), human and monkey cells transformed by SV40 were incapable of producing infectious virus after exposure to SV40, but displayed susceptibility to SV40 DNA. On the other hand, mouse and hamster cells, either normal or SV40-transformed, were resistant both to the virus and to SV40 DNA. Hybrids between permissive and nonpermissive parental cells revealed a complex response: whereas most hybrids tested were resistant, three of them produced a small amount of infectious virus upon challenge with SV40 DNA. All were resistant to whole virus challenge. The persistence of infectious SV40 DNA in permissive and nonpermissive cells up to 96 hr after infection was ascertained by cell fusion. The decay kinetics proved to be quite different in permissive and nonpermissive cells. Adsorption of SV40 varied widely among the different cell lines. Very low adsorption of SV40 was detected in nonsusceptible cells with the exception of the mKS-BU100 cell line. A strong increase in SV40 adsorption was produced by pretreating cells with polyoma virus. In spite of this increased adsorption, the resistance displayed by SV40-transformed cells to superinfection with the virus was maintained.

Response of simian virus 40-transformed cell lines and cell hybrids to superinfection with simian virus 40 and its deoxyribonucleic acid.

Autologous and Homologous Implantation of Human Cells Transformed In Vitro by Simian Virus 40

DURING the past 2 yr, reports from several laboratories1–3 have associated subacute sclerosing panencephalitis (SSPE) with measles on the basis of three observations in patients with this disease: (1) an unusually high level of anti-measles antibody in their serum and spinal fluid; (2) the demonstration in brain sections of measles antigen by means of immunofluorescence; and (3) intranuclear particles resembling myxovirus nucleocapsids in the neurones and oligodendrocytes of the brain seen by electron microscopy. These observations were not concurrent, nor were they universal, but each was noted in several patients.

Subacute Sclerosing Panencephalitis: Structures resembling Myxovirus Nucleocapsids in Cells cultured from Brains

A vaccinia virus-lysed autochthonous tumor cell vaccine (vaccinia oncolysate) is introduced as a new specific, active immunotherapeutic agent against human cancer. Mouse experiments showed the vaccine to be a safe and potent immune mechanism stimulator. Human experimentation was undertaken in the knowledge of relative safety of the components of the vaccine, i.e. vaccinia vaccine and lysed, autochthonous tumor cells. Vaccine-treated patients had advanced metastatic cancer but reacted to one or more common recall antigen skin tests. None of the 13 patients had untoward responses; 7/13 patients had classic delayed hypersensitivity reactions at the vaccine injection sites; and 2/7 patients with injection site reactions had significant reduction in tumor burden. These results indicate that this vaccine is a specific, active immune mechanism stimulator, and may prove to be a useful therapeutic agent in the treatment of human cancer.

Hilary Koprowski

Papers

Response of simian virus 40-transformed cell lines and cell hybrids to superinfection with simian virus 40 and its deoxyribonucleic acid.

Autologous and Homologous Implantation of Human Cells Transformed In Vitro by Simian Virus 40

Subacute Sclerosing Panencephalitis: Structures resembling Myxovirus Nucleocapsids in Cells cultured from Brains

A new approach in specific, active immunotherapy.

Enucleation of cells made simple and rescue of SV40 by enucleated cells made even simpler