Studies on the pathogenesis of feline T-cell neoplasia

Lees, Gillian Margaret (1985) Studies on the pathogenesis of feline T-cell neoplasia. PhD thesis, University of Glasgow.

Abstract

This study was concerned with two principal aspects of T-cell neoplasia in the cat. First, the role that T-cell growth factor (TCGF) had to play in the proliferation of neoplastic T-cells in vitro and secondly, the properties of the viruses associated with the feline thymic lymphosarcomas in this series. The first part of the work (Chapter Two) concerned the production of lymphocyte conditioned medium (Ly-CM) which provided a source of TCGF, or IL-2, as it is better known. This enabled the long-term culture of normal activated feline T-cells which were used in routine blastogenesis assays to determine the level of IL-2 in Ly-CM. The next chapter (Chapter Three) involved the establishment of neoplastic feline T-cell lines in vitro. The cells were derived from thymic lymphosarcomas and were cultured both with and without Ly-CM. Most of these primary cultures required this source of IL-2 for proliferation with two noticeable exceptions (designated T3 and T17) which were extensively studied in the following chapter. The experiments in Chapter Four were designed to determine the role of IL-2 in T-cell neoplasia. The evidence generated suggests that at least some neoplastic T-cell lines have an altered requirement for, or response to, IL-2' in vitro. Recent data from the study of human T-cell neoplasia suggests that enhanced IL-2 receptor expression may be fundamental to the alteration in the requirement for IL-2 observed with some of these cells. The strategy for the further characterisation of the growth requirements of neoplastic T-cells is discussed. In Chapter Five the nature of the viruses associated with the thymic lymphosarcomas and the resultant cell lines was determined. The frequent presence of a novel FeLV which has recombined with a cellular oncogene (c-myc) was reported and the in vitro transmission of these recombinant viruses (FeLV/myc) was demonstrated. The association of additional FeLV subgroups other than A with thymic lymphosarcoma in the series was also observed. The generation of these subgroups and their possible role in the development of neoplasia is discussed. Finally, in Chapter Six, the in vivo passage of the recombinant FeLV/myc virus from the T3 and F422 cell lines was described. These viruses, which originated from cells from thymic lymphosarcomas, rapidly produced the same tumours in susceptible animals. Furthermore, the cells isolated from these tumours readily established in culture without an exogenous source of IL-2. These cells continued to grow under the same conditions as do the parental T3 and F422 cell lines. The relationship between the enhanced expression of the myc oncogene and independence from an exogenous source of IL-2 for growth, is discussed in the light of recent evidence, and future experimental approaches are suggested.

• Item Type: Thesis (PhD)
• Qualification Level: Doctoral
• Keywords: Veterinary science
• Date of Award: 1985
• Depositing User: Enlighten Team
• Unique ID: glathesis:1985-76533
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 19 Nov 2019 14:12
• Last Modified: 19 Nov 2019 14:12
• URI: https://theses.gla.ac.uk/id/eprint/76533