Setty B N, Kulkarni S, Dampier C D, Stuart M J
Department of Pediatrics, Division of Research Hematology, Jefferson Medical College, Thomas Jefferson University, Philadelphia, PA 19107, USA.
Blood. 2001 May 1;97(9):2568-73. doi: 10.1182/blood.v97.9.2568.
To assess whether fetal hemoglobin (HbF) modulates the adhesion of sickle erythrocytes to endothelium, children with homozygous sickle cell anemia (SS disease) were studied, using this physiologically crucial period to evaluate the relationships between HbF and the major erythrocyte adhesion markers. The mean level of CD36(+) erythrocytes was 2.59% +/- 2.15% (+/- SD, n = 40) with an inverse relationship between CD36 positivity and F cells (R = -0.76, P < .000 00 002). In univariate analyses, significant correlations with various hematologic parameters and age were noted. Multiple regression analyses, however, revealed a relationship solely with F cells. Minimal levels of very late activation antigen-4(+) (VLA4(+)) erythrocytes (0.31% +/- 0.45%, n = 40) with relationships similar to those noted for CD36(+) cells were also observed. The subpopulation of strongly adhesive stress reticulocytes was further assessed, using CD71 as their marker. The mean level of CD71(+) erythrocytes was 5.81% +/- 4.21%, with statistical correlates in univariate and multivariate analyses similar to those discussed above. When adhesion ratios were evaluated, inverse correlations were noted between basal and plasma-induced adhesion and F-cell numbers (R = -0.54, P < .0005; R = -0.53, P < .0006, n = 39). In addition, in analyses where basal or plasma-induced adhesion was the dependent variable and the independent variables included F cells and the various adhesion-related parameters, significant relationships solely with F cells were noted. The results demonstrate that SS patients with higher levels of F cells have concomitant decreases in the numbers of CD36(+), VLA4(+), and CD71(+) erythrocytes and that these findings translate into less adherent erythrocytes. These findings extend knowledge regarding the protective effects of HbF in the pathophysiology of sickle cell disease.
为评估胎儿血红蛋白（HbF）是否调节镰状红细胞与内皮的黏附，我们对患有纯合子镰状细胞贫血（SS病）的儿童进行了研究，利用这个生理关键期来评估HbF与主要红细胞黏附标志物之间的关系。CD36(+)红细胞的平均水平为2.59%±2.15%（±标准差，n = 40），CD36阳性与F细胞呈负相关（R = -0.76，P <.000 00 002）。在单变量分析中，观察到与各种血液学参数和年龄有显著相关性。然而，多变量回归分析显示仅与F细胞有关。还观察到极低水平的极晚期活化抗原-4(+)（VLA4(+)）红细胞（0.31%±0.45%，n = 40），其与CD36(+)细胞的关系相似。使用CD71作为标记物进一步评估强黏附应激网织红细胞亚群。CD71(+)红细胞的平均水平为5.81%±4.21%，单变量和多变量分析中的统计学相关性与上述讨论的相似。当评估黏附率时，基础黏附和血浆诱导黏附与F细胞数量之间呈负相关（R = -0.54，P <.0005；R = -0.53，P <.0006；n = 39）。此外在分析中，以基础黏附或血浆诱导黏附为因变量，自变量包括F细胞和各种黏附相关参数，结果显示仅与F细胞有显著关系。结果表明，F细胞水平较高的SS患者，其CD36(+)、VLA4(+)和CD71(+)红细胞数量会相应减少，且这些结果转化为红细胞黏附性降低。这些发现扩展了关于HbF在镰状细胞病病理生理学中保护作用的认识。
