Screening for simian type-D retrovirus infection in macaques, using nested polymerase chain reaction

Area of Science:

• Veterinary Virology
• Molecular Diagnostics
• Primate Health

Background:

• Simian type-D retrovirus (SRV/D) poses a significant threat to macaque health and research.
• Accurate and sensitive detection methods are crucial for managing SRV/D outbreaks in captive macaque populations.

Purpose of the Study:

• To develop and validate a nested polymerase chain reaction (PCR) assay for the simultaneous detection of simian type-D retrovirus (SRV/D) serotypes 1, 2, and 3.
• To evaluate the sensitivity and specificity of the nested PCR assay compared to existing diagnostic methods.

Main Methods:

• Design of primers targeting gag gene sequences for simultaneous amplification of SRV/D serotypes 1, 2, and 3.
• Development of a nested PCR assay for detecting proviral DNA in peripheral blood mononuclear cells (PBMC).
• Parallel testing of 395 macaque PBMC samples using nested PCR, virus isolation, and Western blot (immunoblot) analysis.

Main Results:

• The nested PCR assay demonstrated high sensitivity, detecting as few as 1 to 10 genomic copies.
• Infection was detected in 15.2% of macaques (60/395) by nested PCR, compared to 10.1% (40/395) by virus isolation and 7.1% (28/395) by immunoblot.
• Nested PCR identified positive results in samples negative by other methods, including 7 of 312 immunoblot-negative/virus isolation-negative samples.

Conclusions:

• Nested PCR is a highly sensitive and specific method for the simultaneous detection of SRV/D serotypes 1, 2, and 3.
• The developed assay is a powerful tool for rapid screening and surveillance of SRV/D infection in macaque colonies.
• This molecular diagnostic approach enhances the ability to control and monitor retroviral infections in non-human primate populations.