The ultimate goal of a vaccination is to achieve with minimal side effects a long-lasting, fully protective immune response against a pathogen. Techniques developed over the last decade have allowed the construction of novel types of vaccines that no longer rely on the use of inactivated or attenuated infectious agents, but on individual proteins or even fragments thereof. Before a subunit vaccine can be designed, the different types of immune responses to the different proteins of the infectious agent, and their role in conferring protection have to be elucidated. During the last granting period, we concentrated on defining immune responses to the two internal proteins of rabies virus, i.e., the nucleoprotein and the nominal phosphoprotein. In this application, we propose an in-depth study of immune responses to the viral glycoprotein that is apparently the only viral antigen capable of inducing immune effector mechanisms that can limit the spread of rabies virus once it reaches the central nervous system. Furthermore, we intend to test different prototype vaccines, based on the rabies virus glycoprotein, for induction of protective immune responses. The application is divided into three specific aims. In the first aim, T cell epitopes of the glycoprotein will be defined, the influence of glycosylation of synthetic peptides carrying immunodominant T cell epitopes on their ability to stimulate T cells, especially in vivo, will be tested. The influence of physiological glycosylation patterns of the rabies virus glycoprotein in inducing immune responses will be investigated as well. In the second specific aim, the different immune effector mechanisms to the rabies virus glycoprotein, and their role in providing protection against a peripheral and intracerebral challenge, will be tested using knock-out mice that lack the ability to develop defined types of immune responses. in the third specific aim, we will use vectors expressing the rabies virus glycoprotein to transiently express this protein in vivo. The immune responses induced upon vector immunization will be characterized. Attempts will be made to improve the efficacy by using different expression vectors and different routes of immunization. The duration of expression of the viral antigen and the persistence of vector DNA in mammalian cells will be determined. The effect of co-expressing other immunologically relevant proteins such as cytokines will be investigated.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI027435-08
Application #
2003507
Study Section
Experimental Virology Study Section (EVR)
Project Start
1989-06-01
Project End
1999-12-31
Budget Start
1997-01-01
Budget End
1997-12-31
Support Year
8
Fiscal Year
1997
Total Cost
Indirect Cost
Name
Wistar Institute
Department
Type
DUNS #
042250712
City
Philadelphia
State
PA
Country
United States
Zip Code
19104
Xiang, Z; Ertl, H C (1995) Manipulation of the immune response to a plasmid-encoded viral antigen by coinoculation with plasmids expressing cytokines. Immunity 2:129-35
Otvos Jr, L; Krivulka, G R; Urge, L et al. (1995) Comparison of the effects of amino acid substitutions and beta-N- vs. alpha-O-glycosylation on the T-cell stimulatory activity and conformation of an epitope on the rabies virus glycoprotein. Biochim Biophys Acta 1267:55-64
Wojczyk, B; Shakin-Eshleman, S H; Doms, R W et al. (1995) Stable secretion of a soluble, oligomeric form of rabies virus glycoprotein: influence of N-glycan processing on secretion. Biochemistry 34:2599-609
Xiang, Z Q; Ertl, H C (1994) A simple method to test the ability of individual viral proteins to induce immune responses. J Virol Methods 47:103-16
Otvos Jr, L; Urge, L; Xiang, Z Q et al. (1994) Glycosylation of synthetic T helper cell epitopic peptides influences their antigenic potency and conformation in a sugar location-specific manner. Biochim Biophys Acta 1224:68-76
Xiang, Z Q; Spitalnik, S; Tran, M et al. (1994) Vaccination with a plasmid vector carrying the rabies virus glycoprotein gene induces protective immunity against rabies virus. Virology 199:132-40
Ertl, H C; Dietzschold, B; Otvos Jr, L (1991) T helper cell epitope of rabies virus nucleoprotein defined by tri- and tetrapeptides. Eur J Immunol 21:1-10
Otvos Jr, L; Wroblewski, K; Kollat, E et al. (1989) Coupling strategies in solid-phase synthesis of glycopeptides. Pept Res 2:362-6