George Klein

George Klein was one of the 20th century's most influential tumor biologists at the Karolinska Institutet, whose laboratory made foundational contributions to understanding the relationships between viruses, oncogenes, and cancer. His work on Epstein-Barr virus and Burkitt lymphoma established a paradigm for viral oncogenesis and characterized how EBV transformation of B lymphocytes contributes to lymphomagenesis, particularly in immunocompromised hosts. He was a pioneer of tumor immunology, characterizing tumor-specific transplantation antigens that demonstrated cancer cells express unique antigens recognizable by the immune system, work that conceptually preceded modern cancer immunotherapy. His decades of research at Karolinska contributed to establishing it as a center of international excellence in cancer biology and tumor immunology, training generations of cancer researchers who spread through academic centers globally.