Plasma cells and T cells in BM biopsies of a control case and a CVID patient (patient 2 in Table 1). (A) Normal CD38⁺ plasma cells (red color) in a control biopsy. (B) Absence of CD38⁺ plasma cells in a typical CVID Ia BM biopsy. (C) Sparsely scattered CD3⁺ T cells in typical control biopsy in contrast to a nodular T-cell cluster (D) and diffuse interstitial T-cell infiltrates (E) in a representative CVID bone marrow biopsies. Immunostains: CD38 (A-B), original magnification ×200; and CD3 (C-E), original magnification ×200. Images were obtained with a Zeiss Axioskop 50 microscope equipped with a digital camera (3CCDColor Video Camera; Sony) using Cell P Imaging Software Version 3.3 (Olympus). The figure was finalized applying Adobe Photoshop CS2 Version 9.0. Original magnification 400× (Plan-Neofluar objective 40×/0.75; Zeiss).