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Comparative antiviral and proviral factors in semen and vaccines for preventing viral dissemination from the male reproductive tract and semen

Published online by Cambridge University Press:  19 March 2008

Jane Christopher-Hennings ,
Eric A. Nelson ,
Gary C. Althouse  and
Joan Lunney
Jane Christopher-Hennings*
Affiliation:
Veterinary Science Department, Center for Infectious Disease Research and Vaccinology, South Dakota State University, Brookings, SD 57007-1396, USA
Eric A. Nelson
Affiliation:
Veterinary Science Department, Center for Infectious Disease Research and Vaccinology, South Dakota State University, Brookings, SD 57007-1396, USA
Gary C. Althouse
Affiliation:
Department of Clinical Studies–New Boltan Center, University of Pennsylvania, Kennett Square, PA 19348, USA
Joan Lunney
Affiliation:
Animal Parasitic Diseases Laboratory, ANRI, ARS, USDA, Building 1040, Room 103, BARC-East, Beltsville, MD 20705, USA
*
*Corresponding author. E-mail: Jane.Hennings@sdstate.edu
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Abstract

Many animal and human viruses are disseminated via semen, but there is little information on how to measure and stimulate protective antiviral immunity in the male reproductive tract and semen. This information is important since successful vaccination through the stimulation of protective immune responses could be a mechanism to prevent viral contamination of semen and subsequent wide spread viral dissemination. Even control of the infection by shortening the duration of viral shedding and lowering the viral load in semen would lessen the chances of viral dissemination through this route. This review will highlight the current knowledge of immunity in the male reproductive tract and summarize ‘antiviral’ as well as ‘proviral’ factors in semen such as cytokines, cells, antibodies, antimicrobial peptides, enzymes, hormones and growth factors. These factors must provide a fine balance between ‘immunosuppression’ in semen needed to protect sperm viability and ‘immunocompetency’ to prevent pathogen contamination. The review will also suggest continuing challenges to researchers for preventing viral dissemination via semen and propose a large animal model for continued research in this important area.

Keywords

semenmale reproductive tractantiviralproviralboarporcine reproductive and respiratory syndrome virus (PRRSV)human immunodeficiency virus (HIV)
Type
Review Article
Information
Animal Health Research Reviews , Volume 9 , Issue 1 , June 2008 , pp. 59 - 69
Copyright
Copyright © Cambridge University Press 2008

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