He completed his postdoctoral training in the laboratories of Ganes C. Sen, PhD, Department of Molecular Genetics, Cleveland Clinic, and Steven N. Emancipator, MD, Department of Pathology, Case Western Reserve University, Cleveland. His research revealed the essential kinases for TLR3: EGF receptor and Src phosphorylates, the specific tyrosine residues of TLR3. After clinical fellowship in renal pathology at Brigham and Women's Hospital/Harvard Medical School, Yamashita joined the faculty at Cedars-Sinai in 2016. His research now focuses on understanding the role of EGFR in TLR-mediated injury in glomerulonephritis, a form of vasculitis in kidney glomeruli.