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

Chimeric viral proteins and nucleic acid constructs that code for them and are useful as therapeutic agents are disclosed.

Chimeric viral proteins

Twenty patients with widespread metastatic colorectal carcinoma were infused with 500 mg of the cytotoxic IgG2a monoclonal antibody 17-1A preincubated with autologous peripheral blood leukocytes. Ten patients showed no benefit from such therapy and ten died, with a mean survival time of 7.6 +/- 4.5 months after treatment and a median survival of 6 months. In ten additional patients, the course of disease was modified by antibody therapy; disease in five of these patients stabilized, while tumor size in the other five patients decreased after therapy. Median actual survival in this group of ten patients is presently 24 months; four of these patients died of disease progression within a mean of 15 +/- 5 months. Duration of response was 10.5 +/- 6.7 months after antibody treatment. Treatment tolerance for these 20 patients was excellent in all but one patient, who experienced an anaphylactic reaction during a second infusion with 17-1A.

Immunotherapy of gastrointestinal cancer with monoclonal antibodies

Rabies virus-specific T-cell hybridomas were produced from immune mice by somatic cell fusion. Cloned T-cell hybridomas were studied for antigen specificity using purified virus, a recombinant vaccinia virus expressing rabies glycoprotein and synthetic peptides containing amino acid sequences of rabies viral antigens. Two closely situated T-cell epitopes of rabies glycoprotein, and one of rabies nucleoprotein were identified using synthetic peptides corresponding to amino acid sequences of these proteins. The major histocompatibility gene complex elements that determine the recognition of antigen by these T-cell hybrids were determined using mouse fibroblasts (L cells) transfected with and expressing the I-Ad and I-Ed genes. Some of the T cell hybridomas exhibited significant cytotoxic activity against target cells expressing surface rabies antigens. This T cell mediated cytotoxicity requires cell-to-cell contact between target and effector cells since no by-stander cytotoxicity was observed. The results ...

Rabies virus-specific T cell hybridomas: identification of class II MHC-restricted T-cell epitopes using synthetic peptides.

http://science.sciencemag.org/content/sci/165/3899/1278.full.pdf

Serially Cultured Animal Cells for Preparation of Viral Vaccines

Primate‐mouse hybrid cells were challenged with SV40 DNA and monitored for their ability to produce virus. All of the hybrid cells had lost at least half of their primate chromosomes at the time of challenge. Only SV40 T‐antigen‐positive hybrid cells derived from an SV40‐transformed human parental cell produced SV40. This finding suggests that the chromosome(s) necessary for SV40 replication are easily lost on fusion of mouse and primate cells unless the parental cells are already SV40‐transformed.

Hilary Koprowski

Papers

Chimeric viral proteins

Immunotherapy of gastrointestinal cancer with monoclonal antibodies

Rabies virus-specific T cell hybridomas: identification of class II MHC-restricted T-cell epitopes using synthetic peptides.

Serially Cultured Animal Cells for Preparation of Viral Vaccines

Susceptibility of primate-mouse hybrid cells to SV40.