Highly sensitive and rapid point-of-care testing for HIV-1 infection based on CRISPR-Cas13a system

Human immunodeficiency virus type one (HIV-1) is the leading cause of acquired immunodeficiency syndrome (AIDS). AIDS remains a global public health concern but can be effectively suppressed by life-long administration of combination antiretroviral therapy. Early detection and diagnosis are two key strategies for the prevention and control of HIV/AIDS. Rapid and accurate point-of-care testing (POCT) provides critical tools for managing HIV-1 epidemic in high-risk areas and populations.

In this study, a POCT for HIV-1 RNA was developed by CRISPR-Cas13a lateral flow strip combined with reverse transcriptase recombinase-aided amplification (RT-RAA) technology, the results can be directly observed by naked eyes.

Moreover, with the degenerate base-binding CRISPR-Cas13a system was introduced into the RT-RAA primer designing, the technology developed in this study can be used to test majority of HIV-1 RNA with limit of detection (LOD) 1 copy/μL, while no obvious cross-reaction with other pathogens. We evaluated this method for detecting HIV-1 RNA of clinical samples, the results showed that the sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy were 91.81% (85.03- 96.19%), 100% (92.60-100%), 100% (96.41-100%), 39.14% (25.59-54.60%) and 92.22% (86.89-95.88%), respectively. The lowest viral load detectable by this method was 112copies/mL.

Above all, this method provides a point-of-care detection of HIV-1 RNA, which is stable, simple and with good sensitivity and specificity. This method has potential to be developed for promoting early diagnosis and treatment effect monitoring of HIV patients in clinical.