Feline AIDS : characterization of cytotoxic T cell responses /
To develop a model system with which the host cellular immune
| Main Author: | |
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| Format: | Thesis Book |
| Language: | English |
| Published: |
[Place of publication not identified] :
[publisher not identified] ;
1995.
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| Subjects: | |
| Online Access: | Link to OAKTrust copy http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=742164021&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | To develop a model system with which the host cellular immune response can be studied experimentally in feline immuodeficiency virus (FIV)infected cats, we have examined the in vitro induction and activity of FIV-specific cytotoxic T lymphocytes (CTL) in cats experimentally infected with FIV for a period of 7 to 17 weeks or 20 to 22 months. When effector cells consisted of either fresh peripheral blood mononuclear cells (PBMC) or concanavalin-A and interleukin-2- stimulated cells, only low levels of cytotoxicity were observed. However, the levels of FIV-specific cytotoxicity were consistently higher in both groups of cats following in vitro stimulation of the effector cells with irradiated, FIV- infected autologous T cells and human interleukin-2. The effector cells lysed autologous, but not allogeneic, FIV- infected target cells, and were comprised predominantly of CD8+ T cells, indicating that the FIV-specific cytotoxicity is mediated primarily by major histocompatibility complex (MHC) class I-restricted, CD8+ CTL. We then focused on the FIV capsid protein and examined the in vitro induction and activity of FIV p24 capsid-specific CTL in cats experimentally infected with FIV for 30 to 56 months. An amphotropic murine retroviral vector was used to generate transgenic primary feline T lymphoblasts that expressed the FIV capsid protein. When the autologous capsid-transduced T cells were used in vitro to stimulate CTL responses from PBMC of chronically infected cats, MHC-restricted lysis of virus- infected target cells was observed. The majority of the CTL expressed CD8, and depletion of this population, but not CD4+ T cells, effectively diminished the CTL activity. However, when the autologous capsid-transduced T cells were used as target cells, lysis by capsid-induced effectors was not observed. Analysis of capsid-transduced T cell clones revealed a variable and low level of capsid expression among the clones. This study defines a system to further identify virus-encoded epitopes important in the induction of protective immunity and also demonstrates the potential for using retroviral vectors as a means to induce CTL effector cells that will specifically kill lentivirus-infected cells during lentiviral infection. |
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| Item Description: | Vita. "Major Subject: Veterinary Microbiology". |
| Physical Description: | xi, 98 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references. |