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J C Vogel

Publications and source records attributed to J C Vogel.

28 records · Page 2Linked to original sources
PubMed1996

The derivation and characterization of pig keratinocyte cell lines that retain the ability to differentiate.

Pig skin may be a very useful model for studying human skin biology, since its morphology closely resembles that of human skin. To manipulate pig keratinocytes in vitro, we have analyzed different culture conditions for optimal pig keratinocyte growth and describe here a simple method for culture and extended passage of primary pig keratinocytes on collagen substrates. The colony-forming efficiency and proliferative capacity of primary pig keratinocytes were readily supported by Type I collagen and a final calcium concentration of 0.075 microM. These culture conditions permitted efficient gene transfer into keratinocytes using various cationic lipids at a 4:1 ratio (lipid: DNA). In addition, immortalized pig keratinocyte cell lines, which maintained a normal phenotype, were derived using these optimized culture conditions. By karyotype analysis, two independently derived cell lines had the same chromosomal abnormalities, suggesting a causal role in their immortalization. The keratinocyte cell lines exhibited a differentiated phenotype in response to elevated calcium concentration and were nontumorigenic in in vivo tumor assays. Immortalized pig keratinocyte cell lines that maintain the ability to differentiation may become a valuable tool in the study of epidermal differentiation both in vitro and in vivo. In addition, methods using keratinocytes to deliver genes to pigs in vivo could also be enhanced with these pig keratinocyte cell lines.

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PubMed1995

Cytokine gene expression in epidermis with biological effects following injection of naked DNA.

The epidermis is readily accessible for genetic manipulation and is easily monitored. Using pig skin because it is very similar to human skin morphologically, we have developed a method to transiently express biologically active factors in epidermis. Following direct injection of naked plasmid DNA into skin, DNA is taken up and transiently expressed at high levels by epidermal keratinocytes. Injection of interleukin-8 plasmid DNA into skin results in the appropriate biological response of neutrophil recruitment, demonstrating functional utility. In addition to this model's therapeutic uses, the biological effects of structural gene products on the epidermis could also be studied in vivo.

Animals↗
PubMed1993

Keratinocyte gene therapy.

BACKGROUND: Gene therapy is currently being used in clinical trials to treat a variety of diseases. In keratinocyte gene therapy, the gene that will correct the disease by expressing the normal protein or enzyme is inserted and expressed in keratinocytes. Keratinocytes have significant potential, as a target cell of gene therapy, in the treatment of both systemic diseases as well as skin diseases caused by a genetic defect in keratinocytes. OBSERVATIONS: Although keratinocyte gene therapy is not yet being tested in clinical trials, animal models do exist where keratinocytes are being used to secrete factors such as human growth hormone and factor IX (for hemophilia) into the systemic circulation. Genetic diseases of the skin such as recessive epidermolysis bullosa dystrophica or xeroderma pigmentosum have not yet been treated with keratinocyte gene therapy in animal models. CONCLUSIONS: Keratinocytes have many advantages as a target cell in gene therapy, and progress has been made using animal models. However, the sustained and efficient delivery of factors to the bloodstream by keratinocytes expressing a transgene has not yet been accomplished. Future goals are to obtain adequate levels of the desired factors, hormones, or enzymes for sustained periods of time, either in keratinocytes or in the vascular system.

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PubMed1986

Carbon-13 in natural cholesterol.

In order to assess the feasibility of using stable 13C as a tracer for studying cholesterol metabolism in vivo the 13C content of some commonly consumed foods and the stability of the 13C content of human serum cholesterol has been investigated. A procedure is described for the extraction and purification of cholesterol from food, tissues and serum suitable for 13C analysis by mass spectrometry. The method caused no significant isotope fractionation effects. Generally, there was very little difference between the carbon isotope composition of the diet, the cholesterol and the tissue from which it was derived. However, the difference in 13C composition between tissue and cholesterol of prawns from different parts of the world was considerable, indicating a possible peculiarity in the metabolism of cholesterol by this species. The 13C content of human serum cholesterol on a normal diet did not alter significantly with time, suggesting that stable isotope tracer techniques could be used to measure certain aspects of cholesterol metabolism in vivo.

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PubMed1968

Isotopic equilibrium between shells and their environement.

The carbon-isotopic composition of shell carbonate is shown to be in isotopic equilibrium with bicarbonate dissolved in the water. By measurement of both 13C and 18O in a series of brackish-water shells a mean growth temperature can be deduced.

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PubMedDate not supplied

A direct in vivo approach for skin gene therapy.

In vivo gene therapy is a direct and effective way to express genes in the epidermis. Plasmid DNA that contains the desired gene can be injected intradermally, and it is rapidly absorbed and expressed by the epidermis. Because gene expression following plasmid injection is transient, the two principal therapeutic uses of this approach are genetic immunization and the expression of biological response modifiers to treat skin disease.

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PubMedDate not supplied

Bacterial DNA and CpG-containing oligodeoxynucleotides activate cutaneous dendritic cells and induce IL-12 production: implications for the augmentation of Th1 responses.

BACKGROUND: Unmethylated CpG sequences in bacterial DNA act as adjuvants selectively inducing Th1 predominant immune responses during genetic vaccination or when used in conjunction with protein Ag. The precise mechanism of this adjuvant effect is unknown. Because dendritic cells (DC) are thought to be crucially involved in T cell priming and Th1/Th2 education during vaccination via skin, we characterized the effects of bacterial DNA and CpG-containing oligodeoxynucleotides (CpG ODN) on cutaneous DC. METHODS AND RESULTS: Stimulation with CpG ODN 1826 (6 micrograms/ml) induced activation of immature Langerhans cell (LC)-like DC as determined by an increased expression of MHC class II and costimulatory molecules, loss of E-cadherin-mediated adhesion and increased ability to stimulate allogeneic T cells. Composition-matched control ODN 1911 lacking CpG sequences at equal concentrations was without effect. In comparison to LPS and ODN 1911, CpG ODN 1826 selectively stimulated DC to release large amounts of IL-12 (p40) and little IL-6 or TNF-alpha within 18 h and detectable levels of IL-12 p70 within 72 h. Stimulation with Escherichia coli DNA, but not calf thymus DNA, similarly induced DC maturation and IL-12 p40 production. Injection of CpG ODN into murine dermis induced enhanced expression of MHC class II and CD86 by LC in the overlying epidermis and intracytoplasmic IL-12 p40 accumulation in a subpopulation of activated LC. CONCLUSION: Bacterial DNA and CpG ODN stimulate DC in vitro and in vivo and may preferentially elicit Th1-predominant immune responses because they can activate and mobilize DC, inducing them to produce IL-12.

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