CD4 T cells increased their instantaneous speeds and turning angles between 6.5 and 7 days post-infection (v ̄ = 7.92μm/min versusv ̄ = 9.49μm/min andθ ̄ = 65.7° versusθ ̄ = 69.8°, respectively, Supplemental Figure S1C-D). The gene discussed is CD4; the disease is infection.