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

• Two types of living attenuated poliomyelitis virus were administered by mouth to 24 bottle-fed infants by adding the virus preparations to the formula. Sixteen received the SM strain (representing type 1), two received the TN strain (type 2), and six received both strains at different times. Ingestion of SM was followed promptly by an asymptomatic alimentary infection, demonstrated by isolating the virus from the feces. Repeated doses were necessary to establish the carrier state in three of these infants. Ingestion of TN by two infants was followed similarly by the isolation of type 2 virus from the feces. All infants developed active immunity after the inapparent alimentary infection. It was found safe to administer the virus to infants less than a month old. Two infants who had not received the virus were placed in cribs between those of other infants carrying SM but did not contract the infection. The presence of homotypic antibodies congenitally acquired from the mother did not prevent an active response in infants who received an adequate amount of virus.

Immunization of infants with living attenuated poliomyelitis virus: laboratory investigations of alimentary infection and antibody response in infants under six months of age with congenitally acquired antibodies

Presence of mycoplasma organisms in tissue culture systems and virus pools was detected by titration of the contaminated material on agarose-suspended BHK21/13S cells. The use of this method permitted isolation of mycoplasmas which could not be detected by standard assay methods. Mycoplasma colonies at concentrations ranging from 104 to 106 colony-forming units/ml in agarose-BHK21/13S media could be distinguished from virus plaques, and the two populations of microorganisms could be easily disassociated either by electron microscopy or by biological methods. All isolated mycoplasmas were identified in growth inhibition tests as belonging to the GDL group. The growth inhibition test on agarose-BHK21/13S cell suspension plates could also be applied directly to those strains which could not be isolated by standard assay procedures.

New Assay Procedure for Separation of Mycoplasmas from Virus Pools and Tissue Culture Systems

In the past decade, a growing number of evidence has implicated free radicals in a variety of pathophysiological conditions including aging, cancer, and coronary heart disease. Analyses of different aspects of multiple sclerosis (MS) pathology with respect to oxidative damage have also revealed evidence of free radical injury to the central nervous system (CNS), although attempts to protect the CNS using various antioxidants have met with only moderate success. Several recent studies have reported lower levels of uric acid (UA), a major scavenger of reactive nitrogen species, in MS patients, while other studies found no such correlation. Here, we discuss these studies as well as current efforts to manipulate serum UA levels in MS patients.

Role of Uric Acid in Multiple Sclerosis

Publisher Summary This chapter focuses on the tumor-associated antigens (TAAs) and monoclonal antibodies (MAbs) that are shed in vitro and in vivo. TAAs are those glycoproteins and glycolipids that are expressed on the surface or in the cytoplasm of tumor cells and more often than not are detected on either the normal counterpart of tumor cells or on fetal cells. The term shedding implies the release of antigenic components, in soluble or particulate form, from cells into the tissue culture medium or into blood or other human secretions. Antigens can be released by cells as a function of active metabolic turnover or as a result of cell death. MAbs are undefined circulating TAAs in sera of patients with various solid human tumors. For established tumor markers, MAbs are replacing the use of polyclonal antisera. It is expected that new tumor markers become available that may serve, when necessary, as additional diagnostic tools for each tumor type. MAb-defined tumor markers are available for pancreatic and ovarian carcinoma, which are elevated in more than 80% of patients' sera. For other tumors, combinations of assays need to be developed.

Hilary Koprowski

Papers

Immunization of infants with living attenuated poliomyelitis virus: laboratory investigations of alimentary infection and antibody response in infants under six months of age with congenitally acquired antibodies

New Assay Procedure for Separation of Mycoplasmas from Virus Pools and Tissue Culture Systems

Role of Uric Acid in Multiple Sclerosis

Shedding Of Human Tumor-Associated Antigens in Vitro and in Vivo

A recombinant vaccinia-rabies virus in the immunocompromised host: oral innocuity, progressive parenteral infection, and therapeutics