Simian immunodeficiency virus (SIV) by PCR

Test codes:
S0010 - Ultrasensitive qualitative detection of SIVmac (macaque) by real time polymerase chain reaction.
S0011 - Ultrasensitive qualitative detection of SIVagm strain Tyo-1 (african green monkey) by real time polymerase chain reaction.
S0012 - Ultrasensitive qualitative detection of SIVagm strain AGM-3 (african green monkey) by real time polymerase chain reaction.
S0013 - Ultrasensitive qualitative detection of SIVcpz (chimpanzee) by real time polymerase chain reaction.
S0112 - Ultrasensitive qualitative detection of SIVbab (baboon) by real time polymerase chain reaction.
P0004 - Ultrasensitive qualitative screen for SIV/HIV-2/HIV-1 by real time polymerase chain reaction - detects but does not differentiate SIVsmm, SIVmac, SIVagm, SIVmnd, SIVsyk, SIVcpz, SIVhu, and HIV-1 subtypes A, B, D, F, H and N, and HIV-2 (A and B subtypes). However, assay does not detect HIV-1 subtype C.

In the wild, infections by primate lentiviruses occur only among African monkeys and chimpanzees. Simian immunodeficiency viruses have been isolated from several species of monkeys. Based on sequence homology, the primate lentiviruses can be divided into several groups, of which only three are important from the perspective of primate models of AIDS: HIV-1/SIVcpz, HIV-2/SIVsmm/SIVmac, and SIVagm. The other primate lentiviruses, e.g., SIVmnd, SIVsyk, SIVwcm, SIVrcm, SIVdrl, etc., have not been used as yet to develop models of AIDS. The primate lentiviruses have little or no pathogenicity in their natural hosts and disease appears to result only after transmission to another species.

Unlike apes, many species of monkey are not endangered and breed well in captivity. Large numbers of animals, especially macaques, are readily available. Compared to chimpanzees, macaques are inexpensive, making them suitable for vaccine studies that require large numbers of animals. Unfortunately, with rare exceptions, attempts to infect monkeys with HIV-1 have not been successful. Some laboratories have reported the infection of pig-tailed macaques (Macaca nemestrina) with HIV-1, but virus replication in vivo was at extremely low levels and did not cause disease. Thus, the use of HIV-1/pig-tailed macaques as an AIDS model is not feasible.

The natural host of SIVsmm is the sooty mangabey monkey (Cercocebus atys). SIVsmm is the progenitor of HIV-2 and SIVmac, which appear to have arisen due to cross-species transmission to humans and macaques, respectively. SIVmac infection in macaque monkeys is a well-characterized model of AIDS. HIV-2 and SIVsmm infections of macaques resemble SIVmac infections in most respects. Rhesus (Macaca mulatta), cynomolgus (M. fascicularis), and pig-tailed macaques have been used in the majority of studies, although other macaque species are also susceptible to infection.

Although virus isolation can be used to diagnose SIV infection, a long incubation period is required to obtain results. Furthermore, viral culture is neither sensitive nor specific. Viral culture also increases the potential risk of laboratory personnel contacting this virus. SIV detection by PCR is the most rapid, sensitive and specific method for the diagnosis of this infection.

Utilities:

• Help confirm the disease causing agent
• Differentiate the disease causing SIV strain
• Help ensure that animal colonies are free of SIV
• Early prevention of spread of this virus among a colony
• Minimize personnel exposure to this virus
• Safety monitoring of biological products and vaccines that derive from primates

Specimen requirement: 0.2 ml whole blood in EDTA (purple top) tube.

Contact Zoologix if advice is needed to determine an appropriate specimen type for a specific diagnostic application. For specimen types not listed here, please contact Zoologix to confirm specimen acceptability and shipping instructions.

For all specimen types, if there will be a delay in shipping, or during very warm weather, refrigerate specimens until shipped and ship with a cold pack unless more stringent shipping requirements are specified. Frozen specimens should be shipped so as to remain frozen in transit. See shipping instructions for more information.

Turnaround time: 2 business days

Methodology:
Qualitative real time PCR

Normal range: Nondetected