Figure 2. Constitutive expression of CD38 and elevated CD203a in activated Jurkat/CD73⁻ cells. (A–B) Immunoblotting analysis of plasma membrane fractions from resting and phorbol 12-myristate 13-acetate (PMA)-activated Jurkat/CD73^- cells probed with anti-CD38 (SUN-4B7, IgG1) mAbs or with anti-CD203a (3E8, IgG1) to detect the presence of 45-kDa CD38 (A) and 120-kDa CD203a (B) proteins. (C–D) Proteins with Mr of 71-kDa and 78-kDa, not expressed by Jurkat T cells (not shown), were immunodetected using lysates of epithelial cells from biopsied corneas used as positive controls and probed with anti-CD73 (CB73, IgG1) and anti-CD39 (IgG1) mAbs (right lanes). Isotype-matched irrelevant X63.Ag8 mAb was used as negative controls (left lanes). Mr = molecular weight”.