We propose to produce human monoclonal antibodies (Mabs) to cytomegalovirus (CMV) as a potentially unlimited and safe source of antigen-specific antibodies. We will also analyze their viral antigen specificity and functional effects on the immune response to virus in normal and immunocompromised individuals. While impaired cellular immunity is thought to be the major contributing factor in immunocompromised patients, administration of human plasma with high anti-CMV titers modifies the severity or eliminates CMV infections. The mechanisms whereby antibodies to CMV can modulate infection include neutralization of extracellular virus, complement- mediated lysis of CMV-infected cells, cell-mediated immunity by antibody-dependent cellular cytotoxicity and possible regulatory effects on T cell response to the virus. In this initial phase, the ability to produce human Mabs to CMV has been demonstrated. Of three IgG human anti-CMV Mabs produced, two have been shown to neutralize virus. Preliminary identification has been made of the target molecule of a neutralizing Mab identified within three CMV-associated proteins (MW 46-49,000 60,000 and 140,000). Furthermore, the viral gene epitope recognized by this Mab has tentatively been isolated using a lambda gtll expression system. Lastly, initial studies have shown that human antibodies to CMV will enhance the T cell proliferative response to CMV antigens. Using this approach, the production of a more extensive panel of human Mabs to CMV, particularly of different IgG subclasses, will allow a greater understanding of their specificity and functional effects on CMV and on immune functions of normal and diseased individuals to CMV. The isolation of viral genes encoding CMV-specific proteins identified by these human Mabs will contribute to the development of a recombinant subunit vaccine. Ultimately, these human Mabs should replace human plasma as a source of antibodies in the treatment of CMV infections.

Agency
National Institute of Health (NIH)
Institute
National Institute of Allergy and Infectious Diseases (NIAID)
Type
Research Project (R01)
Project #
5R01AI022557-07
Application #
3133805
Study Section
Experimental Virology Study Section (EVR)
Project Start
1987-09-30
Project End
1993-08-31
Budget Start
1991-09-01
Budget End
1993-08-31
Support Year
7
Fiscal Year
1991
Total Cost
Indirect Cost
Name
Stanford University
Department
Type
Schools of Medicine
DUNS #
800771545
City
Stanford
State
CA
Country
United States
Zip Code
94305
Bradshaw, P A; Duran-Guarino, M R; Perkins, S et al. (1994) Localization of antigenic sites on human cytomegalovirus virion structural proteins encoded by UL48 and UL56. Virology 205:321-8
Perkins, S; Zimmermann, U; Foung, S K (1991) Parameters to enhance human hybridoma formation with hypoosmolar electrofusion. Hum Antibodies Hybridomas 2:155-9
Foung, S; Perkins, S; Kafadar, K et al. (1990) Development of microfusion techniques to generate human hybridomas. J Immunol Methods 134:35-42
Zimmermann, U; Gessner, P; Schnettler, R et al. (1990) Efficient hybridization of mouse-human cell lines by means of hypo-osmolar electrofusion. J Immunol Methods 134:43-50
Foung, S K; Perkins, S; Bradshaw, P et al. (1989) Human monoclonal antibodies to human cytomegalovirus. J Infect Dis 159:436-43
Foung, S K; Perkins, S (1989) Electric field-induced cell fusion and human monoclonal antibodies. J Immunol Methods 116:117-22