BAG1 and CSDE1 protein expression is decreased in DBA erythroblasts. (A) Proliferation of erythroblasts derived from peripheral mononuclear blood of DBA patients and healthy controls. Cumulative cell numbers were calculated; days after in vitro culture initiation are indicated. Black symbols represent healthy controls (c1-c5); gray or open symbols represent DBA patients (d1-d11). Erythroblasts of 5 healthy controls and 7 DBA patients were harvested on day 16 of in vitro culture for protein lysates and RNA isolation; only samples d9 and d11 were harvested on day 14. (B) Protein expression of BAG1 and CSDE1 was analyzed by Western blot using actin as a loading control. The symbols above the Western blot correspond to symbols used in panel A. Patient characteristics are given in supplemental Table 2. BAG1 (C) and CSDE1 (E) protein expression was quantified and corrected to actin expression. BAG1 (D) and CSDE1 (F) transcript levels were quantified by qRT-PCR (except patient d9, n = 4 per sample). Data are also given in supplemental Table 3, lines indicate mean in panels C through F; boxes in panels D and F indicate SEM. Error bars indicate maximum and minimum values. *P = .059; **P = .0023.