CD8A and myeloproliferative neoplasm: Figure 5A shows a representative plot of PLT-bound and PLT-free CD8 T cell proliferation, after a 5-day OKT-3 stimulation. CD8 T cell proliferation is significantly reduced in PLT-bound compared to PLT-free cells in MPN patients (N=6, Figure 5B), with PLT-bound cells undergoing less divisions than PLT-free CD8 T cells. Conversely, after five-hour OKT-3 stimulation, the expression of IFNγ, TNFα and CD107a was increased in PLT-bound CD8 cells compared to the PLT-free population (Figure 5C).