Enhancing antiretroviral delivery to secondary lymph nodes by targeting CD169 + macrophages with HIV-mimicking nanoparticles

Despite significant progress in combinatorial antiretroviral therapy, people living with HIV remain susceptible to co-morbidities and increased risks of mortality. Chronic inflammation and immune activation are correlated with viral persistence in reservoir sites such as secondary lymph nodes and are postulated to be a driver of exaggerated risk of HIV-associated co-morbidities. Previous studies have revealed that low and heterogeneous penetration of antiretrovirals (ARVs) in lymph nodes can contribute to viral persistence. In addition, sub-optimal adherence to daily oral ARVs can lead to the development of antiviral resistance and viral rebound from these sanctuary sites. To overcome these deficiencies, we developed membrane-wrapped poly-lactic acid nanoparticles expressing the ganglioside, GM3 (GM3-NPs) and incorporating dual ARVs, Rilpivirine and Cabotegravir (CAB), for targeted delivery to lymph nodes. We have previously shown that GM3-CD169 mediated uptake of NPs results in their prolonged retention in CD169⁺ macrophage-associated nanoparticle-containing compartments (NPCCs) in vitro, resembling non-degradative virus (HIV-1)-containing compartments. Here, we demonstrate that these NPCCs are surface-accessible and can promote GM3-NP transmission to CD4⁺ T cells upon initiation of cell-to-cell contacts. Consequently, dual ARV-loaded GM3-NPs persisted in CD169⁺ NPCCs and promoted sustained inhibition of both cis- and trans-infection of macrophages and CD4⁺ T cells, respectively. Importantly, GM3-NPs specifically targeted and persisted in lymph node-resident CD169⁺ macrophages in mice. These findings suggest that GM3 incorporation facilitates targeted delivery of NPs to CD169⁺ myeloid cells in lymph nodes and might increase ARV distribution and persistence in lymphatic tissue reservoirs of HIV-1.