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The Development and Use of a Poxvirus Vector System to Protect Pigs Against Swine Influenza Virus Patricia Louise White Foley Iowa State University

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The Development and Use of a Poxvirus Vector System to Protect Pigs Against Swine Influenza Virus Patricia Louise White Foley Iowa State University Iowa State University Capstones, Theses and Retrospective Theses and Dissertations Dissertations 1998 The development and use of a poxvirus vector system to protect pigs against swine influenza virus Patricia Louise White Foley Iowa State University Follow this and additional works at: https://lib.dr.iastate.edu/rtd Part of the Agriculture Commons, Animal Sciences Commons, Immunology and Infectious Disease Commons, Medical Immunology Commons, Microbiology Commons, and the Veterinary Pathology and Pathobiology Commons Recommended Citation Foley, Patricia Louise White, "The development and use of a poxvirus vector system to protect pigs against swine influenza virus " (1998). Retrospective Theses and Dissertations. 12192. https://lib.dr.iastate.edu/rtd/12192 This Dissertation is brought to you for free and open access by the Iowa State University Capstones, Theses and Dissertations at Iowa State University Digital Repository. It has been accepted for inclusion in Retrospective Theses and Dissertations by an authorized administrator of Iowa State University Digital Repository. For more information, please contact [email protected]. tNFORMATION TO USERS This manuscript has been reproduced from the microfilm master. UMI films the text directly firom the original or copy submitted. Thus, some thesis and dissertation copies are in typewriter face, while others may be from any type of computer printer. The quality of this reproduction is dependent upon the quality of the copy submitted. Broken or indistinct print, colored or poor quality illustrations and photographs, print bleedthrough, substandard margins, and improper alignment can adversely affect reproduction. In the unlikely event that the author did not send UMI a complete manuscript and there are missing pages, these will be noted. Also, if unauthorized copyright material had to be removed, a note will indicate the deletion. Oversize materials (e.g., maps, drawings, charts) are reproduced by sectioning the original, beginning at the upper left-hand comer and continuing from left to right in equal sections with small overiaps. Each original is also photographed in one exposure and Is included in reduced form at the back of the book. Photographs included in the original manuscript have been reproduced xerographically in this copy. Higher quality 6" x 9" black and white photographic prints are available for any photographs or illustrations appearing in this copy for an additional charge. Contact UMI directly to order. Bell & Howell Information and Learning 300 North Zeeb Road, Ann Artx>r, Ml 48106-1346 USA 800-521-0600 The development and use of a poxvirus vector system to protect pigs against swine influenza virus by Patricia Louise White Foley A dissertation submitted to the graduate faculty in partial fulfillment of the requirements for the degree of DOCTOR OF PHILOSOPHY Major; Immunobiology Major Professor: Prem S. Paul Iowa State University Ames, Iowa 1998 CopjTight © Patricia Louise White Foley, 1998. All rights reserved. X3MI Niunber: 9941782 Copyright 1998 by Foley, Patricia Louise White All rights reserved. mVH Microform 9941782 Copyright 1999, by UMI Company. All rights reserved. This microform edition is protected against unauthorized copying under Title 17, United States Code. UMI 300 North Zeeb Road Ann Arbor, MI 48103 11 Graduate College Iowa State University This is to certify that the Doctoral dissertation of Patricia Louise White Foley has met the dissertation requirements of Iowa State University Signature was redacted for privacy. Major Professor Signature was redacted for privacy. ajor Program Signature was redacted for privacy. For the Graduate College m TABLE OF CONTENTS Page LIST OF SELECTED ABBREVIATIONS V ABSTRACT viii GENERAL INTRODUCTION 1 Dissertation Organization 5 Literature Review 5 Statement of the problem 34 References 3 5 L EVALUATION OF EVIMUNOGENICITY, SAFETY, AND HOST RESTRICTION OF THE HIGHLY ATTENUATED MVA STRAIN OF VACCINIA VIRUS EXPRESSING HUMAN INFLUENZA VIRUS HEMAGGLUTININ AND NUCLEOPROTEIN GENES 48 Abstract 48 Introduction 49 Materials and Methods 52 Results 56 Discussion 59 References 61 2. RECOMBINANT VACCINIA VIRUS CONTAINING HEMAGGLUTININ AND NUCLEOPROTEIN GENES FROM A PORCINE STRAIN OF INFLUENZA VIRUS PROTECTS PIGS AGAINST SWINE INFLUENZA VIRUS 77 Structured Abstract 77 Introduction 79 Materials and Methods 83 Results 89 Discussion 92 References 96 3. EVALUATION OF INHIBITION OF IMMUNE RESPONSE TO VACCINATION FOLLOWING SEQU'ENTIAL USE IN PIGS OF TWO MODIFIED VACCINLA VIRUS ANKARA (MVA) RECOMBINANTS EXPRESSING HETEROLOGOUS INFLUENZA VIRUS GENES 113 Abstract 113 Introduction 114 Materials and Methods 118 Results 124 Discussion 126 References 128 GENERAL CONCLUSIONS References V LIST OF SELECTED ABBREVIATIONS AGIO agar gel immunodifilision assay. CDCD caesarean-derived colostrum-deprived. CEF chicken embryo fibroblast cells. cELISA competitive enzyme-linked immunosorbent assay. CPE cytopathic effect. EID50 mean egg infectious dose. FFU fluorescent focal units. GMT geometric mean titer. HA hemagglutinin, the major surface protein of influenza virus and the target of influenza virus-neutralizing antibody. HAI hemagglutination inhibition assay, which measures serum antibody to HA. HlNl a designation for a type A influenza virus with a hemagglutinin gene of HI subtype (out of 15) and a neuraminidase gene ofNl subtype (out of 9). H3N2 another subtype of tj^je A influenza virus. H1N2 believed to be the result of reassortment of genetic segments of HlNl and H3N2 influenza viruses. IA/31 A/Swine/Iowa/31, an HlNl influenza virus of the 'classic' SIV variety, IM intramuscular (route of inoculation). EST intranasal (route of inoculation). rN88 A/Swine/In/1726/88, a reference strain of'classic' HlNl SIV isolated at the VI University of Wisconsin. IN/88 A/Swine/In/1726/88, a reference strain of'classic' HlNl SIV isolated at the University of Wisconsin. ISU Srv an Iowa field isolate of SIV, Iowa State University Veterinary Diagnostic Laboratory swine isolate #40776. MN/88 an HlNl influenza virus isolated from turkeys in Minnesota. MO/87 an HlNl influenza virus isolated from turkeys in Missouri. MVA modified vaccinia Ankara, highly attenuated strain of vaccinia virus. MVA-HA-NP recombinant MVA virus expressing HA and NP genes of A/PR/8/34, a human HlNl strain of influenza virus. NIVA/PR8 recombinant MVA virus expressing HA and NP genes of A/PR/8/34, a human HlNl strain of influenza virus. MVA/SrV recombinant MVA virus expressing HA and NP genes of an Iowa field strain of HlNl swine influenza virus. NP nucleoprotein, the major target antigen for cytotoxic T lymphocytes, which improve influenza virus clearance. PFU plaque-forming units. PR8 A/PR/8/34, a human HlNl strain of influenza virus. PR/8 A/PR/8/34, a human HlNl strain of influenza virus. SD/86 an HlNl influenza virus isolated from turkeys in South Dakota. SI swine influenza, a disease generally of high morbidity and low mortality in pigs. vii SrV swine influenza virus. WR nonattenuated Western Reserve strain of vaccinia virus, has the fiill vaccinia virus host range. WR-HA-NP a WR recombinant expressing the HA and NP genes of the human HlNl PR8 strain of influenza virus. viii ABSTRACT The hypothesis tested in this dissertation is that a poxvirus vector system containing influenza virus immunogens protects pigs against swine influenza virus (SrV)-associated disease. The host range-restricted, highly attenuated, and safety-tested modified vaccinia virus Ankara (MVA) strain was used as a vector for influenza virus hemagglutinin (HA) and nucleoprotein (NP) genes from the HlNl A/PR/8/34 (PRS) human isolate. This recombinant virus has previously been shown to protect mice against lethal challenge with PRE. First, the ability of the MVA/PR8 recombinant to protect pigs against SIV was examined. Second, a new recombinant, designated NIVA/SrV, was constructed containing the HA and NP genes from a field isolate of SIV submitted to the Iowa State University Veterinary Diagnostic Laboratory. The MVA/SIV recombinant was evaluated for immunogenicity in vaccinated pigs subsequently challenged with SFV. Third, the possibility of inhibition of immune response in secondary vaccination, following sequential use of two IvIVA recombinants, was explored using the MVA/PR8 and MVA/SIV constructs. The first study demonstrated that protection afforded by MVA/PR8 against SFV was less than complete, that infection, clinical signs of illness, and viral shedding still occurred, albeit to a lesser degree than in nonvaccinated controls. The second study indicated the marked improvement in protection against SIV when pigs were vaccinated with the MVA/SIV construct. The third study provided evidence that sequential use of such MVA recombinants containing inserts from two strains of influenza virus, given two months apart, still generated appropriate immune responses to the different inserts. 1 GENERAL INTRODUCTION Swine influenza is a major respiratory problem in swine. Infected herds are common and widespread. Moreover, there are several antigenically distinct subtypes of the causative virus that can produce disease in susceptible pigs. There is only one vaccine available, an inactivated product derived from a single strain, which cannot provide protection against all virulent strains. Immunity against influenza virus largely consists of a strong subtype-specific humoral response to a major surface antigen and a heterotypic cell-mediated response to a major internal protein. A live virus vaccine could generate these
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