Abstract

Transformation of cells with herpes simplex virus Type 2 (HSV- 2)occurs by an unknown mechanism. No specific gene or gene product has been consistently associated with HSV-2 transformation as is the case for other tumor viruses. This study was performed in an attempt to associate HSV-2-transformation with specific growth factors in order to develop a testable model for HSV-2-transformation. For some tumor viruses, particularly those containing RNA, there has been a central concept (autocrine secretion) linking oncogenes and growth factors. This concept centers on the ability of the cancer cells to produce and respond to their own autologous factors. We report here the isolation and characterization of four growth regulatory factors produced by H238, an HSV-2-transformed mouse tumor cell line.

The H238 cells were grown in culture flasks to two-thirds confluency in medium containing 10% fetal bovine serum. The medium was removed, the cells were washed and medium without serum was added to the cells. At intervals of 48 hours, this conditioned medium (H238-CM), which contained growth regulatory factors, produced by the cells, was withdrawn and stored frozen. These factors were separated from the H238-CM by heparin-sepharose affinity chromatography into three peaks of mitogenic activity and a fourth containing inhibitory activity for splenocytes. The three peaks of mitogenic activity have been identified based on physiochemical characteristics: the first supported the anchorage-independent growth of EGF treated NRK-c-49 cells and resembles transforming growth factor-^ (TGF-/3); the second bound to lectin-coated sepharose beads and was sensitive to trypsin, neuroaminidase, and the reducing agent dithiothreitol (DTT) and, resembled a platelet-derived growth factor (PDGF)-like factor; and the third displaced [ 125I]-labeled basic fibroblast growth factor (bFGF) in a dose dependent fashion when tested with a radioimmune assay (RIA). The fourth peak was inhibitory for a variety of splenocyte function assays. It inhibited lectininduced blastogenesis, allogenic mixed lymphocyte reaction (MLR), and It appeared to act on splenocyte Gq/G-^ transition causing growth arrest by inhibiting c-myc proto-oncogene IL-2 production by splenocytes. expression. A model for the interaction of these factors in vivo is presented with an emphasis on testability.

LLU Discipline

Microbiology

Department

Microbiology

School

Graduate School

First Advisor

Robert L. Nutter

Second Advisor

E. Clifford Herrmann

Third Advisor

James D. Kettering

Fourth Advisor

Benjamin Lau

Fifth Advisor

Robert Teel

Degree Name

Doctor of Philosophy (PhD)

Degree Level

Ph.D.

Year Degree Awarded

1988

Date (Title Page)

6-1988

Language

English

Library of Congress/MESH Subject Headings

Herpesvirus hominis; Oncogenic Viruses -- growth & development

Type

Dissertation

Page Count

vii; 101

Digital Format

PDF

Digital Publisher

Loma Linda University Libraries

Usage Rights

This title appears here courtesy of the author, who has granted Loma Linda University a limited, non-exclusive right to make this publication available to the public. The author retains all other copyrights.

Collection

Loma Linda University Electronic Theses and Dissertations

Collection Website

http://scholarsrepository.llu.edu/etd/

Repository

Loma Linda University. Del E. Webb Memorial Library. University Archives

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Included in

Microbiology Commons

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