**Simian-Human Immunodeficiency Viruses and Their Impact on Non-Human Primate Models for AIDS**

Lara E. Pereira, Priya Srinivasan and James M. Smith

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/53556

#### **1. Introduction**

Non-human primates (NHP) have been indispensable to the study of simian immunodeficiency (SIV)/human immunodeficiency (HIV) infection, pathogenesis, and the development of prophylactic and therapeutic interventions to prevent transmission and progression to disease. A number of SIV and chimeric simian-human immunodeficiency virus (SHIV) challenge stocks have significantly advanced the NHP model, making it possible to identify and better understand factors that influence virus transmission, acute infection, pathogenesis and the eventual progression to AIDS. The development of SHIV recombinant viruses, in particular, has been especially advantageous in that it provides a more relevant research tool for studying properties of HIV-1 infection in a NHP setting. These include HIV-1 envelope characteristics that affect transmission and pathogenesis. SHIV constructs also allow for the evaluation of the efficacy of anti-HIV microbicide formulations and vaccines that are directed against envelope and other critical virus components such as reverse transcriptase. While beneficial, the vast number of virologicallydistinct challenge stocks and the growth of the NHP challenge model repertoire to now include rhesus, pigtail and cynomolgus macaques, have collectively introduced an increased level of complexity with regard to experimental design and data interpretation. Furthermore, some virus stocks have virological properties that limit applications in novel areas of drug discovery, prompting the development of new generation SHIV challenge stocks. The purpose of this chapter is to therefore summarize efforts that have been made to characterize both SIV/SHIV challenge stocks and NHP hosts, to highlight the development of new generation SHIV, and how these novel challenge stocks have advanced the SHIV NHP challenge model and anti-HIV drug and vaccine development.

© 2012 Smith et al., licensee InTech. This is an open access chapter distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2012 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
