PTK2B and Splenomegaly: Both this and another pseudo-PTK domain mutant, JAK3 M511I, were also shown to induce a transplantable T-ALL-like disease with long latency, which was characterized by the ligand-independent proliferation of T cells, while the PTK domain mutant L857Q displayed splenomegaly and lymphadenopathy without the peripheral increase in T cells [41].