The observed difference in binding is due to the difference in mean binding of Tregalizumab to CD4 ([BT-061+/CD4−]), which is significantly lower in RA patients compared with healthy subjects (Figure 5b), whereas the overall CD4 expression ([CD4+/CD4−]) in general is comparable between RA patients and healthy subjects (Figure 5c). The gene discussed is CD4; the disease is rheumatoid arthritis.