Professor, Harvard Medical School
Cerebrospinal fluid (CSF) fills the brain’s ventricles or cavities. It delivers a rich cocktail of health and growth promoting factors for the developing brain, while also providing an essential fluid cushion that protects the brain from injury. We are investigating how CSF composition, and in turn, brain development, are regulated.
The Lehtinen lab is interested in understanding how brain development and health are regulated. In the developing brain, neural precursor cells divide immediately adjacent to CSF-filled ventricles. We have found that the CSF provides a diverse library of secreted factors that help coordinate neurogenesis and brain development from the earliest stages of brain development, during the time of neural tube closure. At later stages, most CSF is produced by the choroid plexus, a tissue located in each ventricle in the brain. We have estimated the choroid plexus secretome, using next-generation sequencing and proteomics tools. In the process, we uncovered that the choroid plexus has a distinct identity in different ventricles, which leads to the secretion of unique proteomes into the brain’s ventricular system in an age-dependent manner. These findings raise exciting questions about regionalization and regulation of the entire choroid plexus-CSF system, and we are fascinated by how these processes are regulated across the lifespan. We employ a multi-tiered approach that draws on molecular and cellular neuroscience, genetics, proteomics, and imaging to investigate the system in health and disease.