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.

/pdf/nitric-oxide-and-peroxynitrite-in-health-and-disease-3uuuqgfdcz.pdf

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

Identification and isolation of a common tumor-associated molecule using monoclonal antibody☆

Three entities--multiple sclerosis, tropical spastic paraparesis, and human T-lymphotropic virus type I (HTLV-I)-associated myelopathy (HAM)--may represent manifestations of the same disease, with HTLV-I-like virus playing a role in their etiology. Tests for the presence of antibodies reacting with either HTLV-I-like virions or with p24 (gag) antigen, expression of HTLV-I antigen by cells of peripheral blood lymphocytes or cerebrospinal fluid, and viral sequences detected by in situ hybridization are essential to establish the role of HTLV-I-like virus in the disease. It is not yet known whether an incomplete form of the virus persists in the tissue following initial infection or whether the virus in question shares the gag protein with HTLV-I but carries the envelope of a different virus. It is recommended that investigative units comprising neurologists and laboratory workers be established as soon as possible to pursue vigorously the leads that may throw some light on the etiology of chronic neurological diseases such as multiple sclerosis.

HTLV-I and chronic nervous diseases: present status and a look into the future.

Ova from superovulated Swiss albino ICR mice were exposed to 1, 10, and 40 μg cytochalasin B/ml in Whitten and Biggers medium (WBM) for intervals up to 24 hours. Controls were incubated in ordinary medium or in medium containing dimethylsulfoxide (DMSO) in an amount equivalent to that used to dissolve cytochalasin B, taking dilution into account. The ova were mounted on slides in egg albumin, stained by the Feulgen method and counterstained with light green SF, or they were processed for electron microscopy. The DMSO treatment, as determined by either light or electron microscopy, had no essential effect. Eggs treated with 10 or 40 μg cytochalasin/ml did not exhibit the fragmentation observed in some of the control ova. Treated eggs contained either several spherical bodies, which sometimes reached a size of 8 to 10 μ, or as many as 20 smaller bodies, stainable with light green SF and positive for proteins when stained with mercury-bromphenol blue. These bodies, first observed after exposure for eight hours to cytochalasin, were revealed by electron microscopy to be groups of crystalloids which occasionally entrapped microfilaments or granules. Neither the spacial relationship of crystalloids to cell organelles nor the preliminary stages of their formation could be observed. Since little protein synthesis occurs in unfertilized eggs, and the addition of 50 and 250 μg of puromycin did not prevent formation of these bodies, it is suggested that they were formed by the crystallization of proteinaceous material already present in the eggs.

Crystalloid formation in unfertilized mouse ova under influence of cytochalasin B.

Immunologic Cross-Reactivity Between Antigen of Unfertilized Mouse Eggs and Mouse Cells Transformed by Simian Virus 40

SummaryThe cytoplasmic inclusions present in rabbit endothelial and hamster kidney fibroblast cells, chronically infected with CVS rabies virus, can be stained green or red by acridine orange and are colored red by methyl green pyronin. These staining reactions do not appear to be caused by the presence of nucleic acids in the inclusions. RNA, which is sensitive to digestion with RNase, is stained by toluidine blue and toluidine blue-molybdate (Method C) in the inclusions. The inclusions appear to contain viral anti-genic protein and small amounts of RNA.The authors wish to thank Christine J. Merrick and Oksana Bohachevsky of Jefferson Medical School, and Jean McClure, The Wistar Institute, for valuable technical assistance.

Hilary Koprowski

Papers

Identification and isolation of a common tumor-associated molecule using monoclonal antibody☆

HTLV-I and chronic nervous diseases: present status and a look into the future.

Crystalloid formation in unfertilized mouse ova under influence of cytochalasin B.

Immunologic Cross-Reactivity Between Antigen of Unfertilized Mouse Eggs and Mouse Cells Transformed by Simian Virus 40

Cytochemistry of inclusion bodies in tissue culture cells infected with rabies virus.