Dolutegravir induces FOLR1 expression during brain organoid development.

The brain and spinal cord are formed during neurulation, a developmental process that occurs during the first month of pregnancy and can be modified by low serum levels of folic acid (FA), environmental factors, or genetic predispositions. In 2018, data from a surveillance study in Botswana, a country with one of the highest incidences of human immunodeficiency virus (HIV) and lacking mandatory food folate fortification programs, revealed an increased risk of neural tube defects (NTDs) among newborns whose mothers were taking Dolutegravir (DTG) during the first trimester of pregnancy. Subsequently, the World Health Organization and the U.S. Food and Drug Administration issued recommendations and guidelines emphasizing the potential risks associated with the use of DTG-based antiretroviral therapies during pregnancy. To elucidate the potential mechanisms underlying the DTG-induced NTDs, we sought to employ a rapid experimental system to test specific hypotheses. Brain organoids are three-dimensional cellular structures that can be used to study early neural development, and to assess the potential neurotoxicity of drugs and other compounds. To understand the development of brain organoids in the presence of DTG, we analyzed gene expression from RNA sequencing together with biomechanical information from Optical Coherence Tomography, Optical Coherence Elastography and Brillouin microscopy. Our sequencing data indicates that DTG induces the expression of folate receptor (FOLR1) and modulates the expression of genes required for neurogenesis. The Brillouin frequency shift observed at the surface of DTG-exposed brain organoids indicates an increase in superficial tissue stiffness, while reverberant Optical Coherence Elastography measurements indicate decreased organoid volumes and an internal stiffness decrease.