Carmel R, Coltman C A, Brubaker L H
Proc Soc Exp Biol Med. 1975 Apr;148(4):1217-22. doi: 10.3181/00379727-148-38720.
Serum unsaturated vitamin B12-binding capacity (UBBC) has been shown to fluctuate with neutrophil levels and has been reported to correlate with TBGP in normal and hyperleukocytic states. However, the present report demonstrates that the above relationship is not present in neutropenia, suggesting that some of our concepts regarding UBBC may have to be reexamined, since factors other than TBGP appear to be operative. There was a wide scatter of UBBC values among the 39 neutropenic subjects studied, the mean being significantly above normal. There were few low values. High UBBC was primarily confined to subjects with transient neutropenia. Normal values were generally seen in steady neutropenia. The difference in UBBC was primarily due to Transcobalamin I, the other serum binders being similar in both groups. No other significant diagnostic pattern of UBBC was found. Recovery from neutropenia was accompanied by a rise in UBBC in all cases except in four patients whose UBBC was initially very high and fell with recovery. No discernible pattern of serum B12 levels existed, although subnormal levels without evidence of B12 deficiency were found in three of the seven patients with aplastic anemia. Serum B12 levels did not change with recovery in approximately half of the neutropenic subjects, change being variable in the others. Neither serum B12, UBBC, total B12-binding capacity, or any of the three serum B12 binders correlated with neutrophil count, bone marrow findings, TBGP, or granulocyte turnover rate.
血清不饱和维生素B12结合能力（UBBC）已被证明会随中性粒细胞水平波动，并且据报道在正常和高白细胞状态下与转钴胺蛋白（TBGP）相关。然而，本报告表明，在中性粒细胞减少症中不存在上述关系，这表明我们关于UBBC的一些概念可能需要重新审视，因为似乎有其他因素在起作用。在研究的39名中性粒细胞减少症患者中，UBBC值分布广泛，平均值显著高于正常水平。低值很少。高UBBC主要局限于短暂性中性粒细胞减少症患者。在持续性中性粒细胞减少症患者中通常可见正常数值。UBBC的差异主要归因于转钴胺蛋白I，两组中的其他血清结合蛋白相似。未发现其他显著的UBBC诊断模式。除了4例UBBC最初非常高且随恢复而下降的患者外，所有中性粒细胞减少症患者恢复时UBBC均升高。虽然在7例再生障碍性贫血患者中有3例发现血清B12水平低于正常但无B12缺乏证据，但未发现可识别的血清B12水平模式。大约一半的中性粒细胞减少症患者血清B12水平在恢复时没有变化，其他患者变化不一。血清B12、UBBC、总B12结合能力或三种血清B12结合蛋白中的任何一种均与中性粒细胞计数、骨髓检查结果、TBGP或粒细胞周转率无关。
