Retroviruses (HIV/SIV)

Retroviruses belong to the Retroviridae family, a distinct group of single-stranded RNA viruses. These viruses are unique because, unlike most cellular organisms, they carry their genetic information in RNA rather than DNA. A specific enzyme within a retrovirus, reverse transcriptase, enables it to transcribe DNA from RNA when it invades a host cell. By integrating its genetic material with the host's, the retrovirus becomes part of the host's genome for life. While many retroviruses are harmless, some cause a variety of serious diseases in humans and animals, such as tumors, autoimmune diseases, rare anemias, and immunodeficiency syndromes - including acquired immune deficiency syndrome (AIDS), which is associated with HIV infection. The four currently identified human retroviruses each infect CD4-bearing T-cells, a type of immune system cell. These viruses were only identified in the 1980s when it became possible to culture T-cells in vitro. Because retroviruses are prone to mutations, viruses in this family often become resistant to antiviral drugs within a relatively short time period.

Southern Research offers comprehensive antiviral evaluation capabilities for HIV and SIV, ranging from initial determinations of antiviral efficacy to highly innovative studies related to novel mechanisms of action. We specialize in working closely with clients to develop each antiviral compound to its maximum efficacy. Our diverse antiretroviral evaluation capabilities are designed to accommodate the full range of our clients' needs, from the initial screening of compounds to the completion of all recommended studies outlined in the U.S. Food and Drug Administration's "Guidance for Industry: Antiviral Product Development - Conduction and Submitting Virology Studies to the Agency." (view PDF) These capabilities comprise nonclinical virology studies that include:

In vitro evaluations

• Antiviral testing
• Vaccine testing
• Animal model support assays
• Custom assay development

In vivo evaluations

• Antiviral models
• Vaccine models
• Model development