HIV-1 mRNA knockdown with CRISPR/CAS9 enhances neurocognitive function

Area of Science:

• Neuroscience
• Genetics
• Virology

Background:

• HIV-1 establishes persistent reservoirs in the central nervous system (CNS) within mixed glia.
• Gene editing, particularly CRISPR/Cas9, offers potential for HIV-1 reservoir elimination.
• The efficacy of CRISPR/Cas9 in removing HIV-1 proteins from mixed glia remains unevaluated.

Purpose of the Study:

• To evaluate the efficacy of adeno-associated virus 9 (AAV9)-CRISPR/Cas9 gene editing in eliminating HIV-1 messenger RNA (mRNA) from cortical mixed glia.
• To assess the impact of CRISPR/Cas9 treatment on neurobehavioral outcomes related to HIV-1-associated neurocognitive disorders (HAND).

Main Methods:

• In vitro: Mixed glia from HIV-1 transgenic (Tg) rats were treated with varying doses of AAV9-CRISPR/Cas9.
• In vivo: HIV-1 Tg rats received retro-orbital inoculation of AAV9-CRISPR/Cas9.
• HIV-1 mRNA levels were quantified using in situ hybridization.
• Temporal processing was assessed to evaluate neurocognitive function.

Main Results:

• In vitro, a dose-dependent decrease in HIV-1 mRNA was observed in a subset of treated mixed glia.
• In vivo, CRISPR/Cas9 treatment resulted in significant excision (approx. 53.2%) of HIV-1 mRNA in the medial prefrontal cortex.
• CRISPR/Cas9 treatment partially restored the developmental trajectory of temporal processing.

Conclusions:

• Mixed glia are susceptible to gene editing interventions.
• AAV9-CRISPR/Cas9 demonstrates potential as a therapeutic strategy for HAND by reducing HIV-1 mRNA.
• CRISPR/Cas9 may offer clinical benefits for HAND even without complete viral genome eradication.