An optimized intracerebroventricular injection of CD4⁺ T cells into mice

The blood-brain barrier acts as a major barrier for the entrance of most therapeutics into the brain, impeding treatment for neurological disorders. Intracerebroventricular (ICV) injection of T cells is a useful tool for cell therapy of neurological disorders including neurodegenerative and neuropsychiatric diseases and brain tumors. Here, we present an optimized ICV injection of T cells with improved injection efficiency at pathological sites within the brain parenchyma. We describe details of the surgical procedure and verification of injection via immunohistochemistry. For complete details on the use and execution of this protocol, please refer to Fisher et al. (2014); Strominger et al., (2018); Mittal et al. (2019); Eremenko et al. (2019).