Phenotypical and functional abnormalities of circulating neutrophils in patients with β-thalassemia.
- 作者列表："Buttari B","Profumo E","Caprari P","Massimi S","Sorrentino F","Maffei L","Gabbianelli M","Riganò R
:β-Thalassemia is an inherited single gene disorder related to reduced synthesis of the β-globin chain of hemoglobin. Patients with β-thalassemia present variable clinical severity ranging from asymptomatic trait to severe transfusion-dependent anemia and multiple organs complications. Moreover, multiple immune abnormalities are a major concern in β-thalassemia patients. Aberrant neutrophil effector function plays a pivotal role in infection susceptibility in these patients. In severe and persistent inflammation, immature neutrophils are released from the bone marrow and are functionally different compared with mature ones. Despite some abnormalities reported for thalassemia patient's immune system, few data exist on the characterization of human neutrophils in β-thalassemia. The aim of this study was to investigate the phenotype and function of circulating neutrophil subsets in patients with β-thalassemia major and with β-thalassemia intermedia divided in transfusion-dependent and non-transfusion-dependent. By the use of immunochemical and cytofluorimetric analyses, we observed that patients' CD16+ neutrophils exhibit abnormalities in their phenotype and functions and the abnormalities vary according to the clinical form of the disease and to the neutrophil subset (CD16bright and CD16dim). Abnormalities include altered surface expression of the innate immune receptor CD45, Toll-like receptor 4, and CD32, reduced ability to produce an oxidative burst, and elevated levels of membrane lipid peroxidation, especially in patients with a more severe form of the disease. Overall, our results indicating the occurrence of an immuno-senescent phenotype on circulating neutrophils from thalassemia patients suggest the usefulness of neutrophil feature assessment as a tool for better clinical management of β-thalassemia.
: β-地中海贫血是一种遗传性单基因疾病，与血红蛋白 β-珠蛋白链合成减少有关。Β-地中海贫血患者呈现从无症状特征到严重输血依赖性贫血和多器官并发症的可变临床严重程度。此外，多重免疫异常是 β-地中海贫血患者的主要关注点。异常的中性粒细胞效应子功能在这些患者的感染易感性中起关键作用。在严重和持续的炎症中，未成熟的中性粒细胞从骨髓中释放出来，并且与成熟的中性粒细胞相比在功能上是不同的。尽管报道了地中海贫血患者免疫系统的一些异常，但关于 β-地中海贫血中的人中性粒细胞的特征的数据很少。本研究的目的是调查重型 β-地中海贫血和中间 β-地中海贫血患者循环中性粒细胞亚群的表型和功能，分为输血依赖性和非输血依赖性。通过使用免疫化学和细胞荧光分析，我们观察到患者的CD16 + 嗜中性粒细胞在其表型和功能方面表现出异常，并且异常根据疾病的临床形式和嗜中性粒细胞亚群 (CD16bright和CD16dim) 而变化。异常包括先天免疫受体CD45、Toll样受体4和CD32的表面表达改变，产生氧化爆发的能力降低，以及膜脂质过氧化水平升高，特别是在具有更严重形式的疾病的患者中。总的来说，我们的结果表明地中海贫血患者循环中性粒细胞出现免疫衰老表型，这表明中性粒细胞特征评估作为更好地治疗 β-地中海贫血的工具是有用的。
METHODS:BACKGROUND:Thalassemia is one of the most common monogenetic diseases in the south of China and Southeast Asia. Hemoglobin Bart's hydrops fetalis syndrome was caused by a homozygous Southeast Asian deletion (-/-) in the HBA gene. Few studies have proved the potential of screen for Bart's hydrops fetalis using fetal cell-free DNA. However, the number of cases is still relatively small. Clinical trials of large samples would be needed. OBJECTIVE:In this study, we aimed to develop a noninvasive method of target-captured sequencing and genotyping by the Bayesian method using cell-free fetal DNA to identify the fetal genotype in pregnant women who are at risk of having hemoglobin Bart hydrops fetalis in a large-scale study. STUDY DESIGN:In total, 192,173 couples from 30 hospitals were enrolled in our study and 878 couples were recruited, among whom both the pregnant women and their husbands were detected to be carriers of Southeast Asian type (-/αα) of α-thalassemia. Prenatal diagnosis was performed by chorionic villus sampling, amniocentesis, or cordocentesis using gap-polymerase chain reaction considered as the golden standard. RESULTS:As a result, we found that the sensitivity and specificity of our noninvasive method were 98.81% and 94.72%, respectively, in the training set as well as 100% and 99.31%, respectively, in the testing set. Moreover, our method could identify all of 885 maternal samples with the Southeast Asian carrier and 36 trisomy samples with 100% of sensitivity in T13, T18, and T21 and 99.89% (1 of 917) and 99.88% (1 of 888) of specificity in T18 and T21, respectively. CONCLUSION:Our method opens the possibility of early screening for maternal genotyping of α-thalassemia, fetal aneuploidies in chromosomes 13/18/21, and hemoglobin Bart hydrops fetalis detection in 1 tube of maternal plasma.
METHODS:OBJECTIVES:Sickle cell disease (SCD) is a serious illness with disabling acute and chronic pain that needs better therapies, but insufficient patient participation in research is a major impediment to advancing SCD pain management. The purpose of this article is to discuss the challenges of conducting an SCD study and approaches to successfully overcoming those challenges. DESIGN:In a repeated-measures, longitudinal study designed to characterize SCD pain phenotypes, we recruited 311 adults of African ancestry. Adults with SCD completed 4 study visits 6 months apart, and age- and gender-matched healthy controls completed 1 visit. RESULTS:We recruited and completed measures on 186 patients with SCD and 125 healthy controls. We retained 151 patients with SCD with data at 4 time points over 18 months and 125 healthy controls (1 time point) but encountered many challenges in recruitment and study visit completion. Enrollment delays often arose from patients' difficulty in taking time from their complicated lives and frequent pain episodes. Once scheduled, participants with SCD cancelled 49% of visits often because of pain; controls canceled 30% of their scheduled visits. To facilitate recruitment and retention, we implemented a number of strategies that were invaluable in our success. CONCLUSION:Patients' struggles with illness, chronic pain, and their life situations resulted in many challenges to recruitment and completion of study visits. Important to overcoming challenges was gaining the trust of patients with SCD and a participant-centered approach. Early identification of potential problems allowed strategies to be instituted proactively, leading to success.
METHODS:OBJECTIVES:Sickle cell anemia is the commonest genetic disorder in India, and the frequency of the sickle cell gene is very high in the remote tribal areas where facilities are generally limited. Therefore, a rapid and affordable point-of-care test for sickle cell disease is needed. METHODS:The diagnostic accuracy of HemoTypeSC was evaluated against automated high-performance liquid chromatography (HPLC) as the gold standard for its efficacy in a newborn screening program. RESULTS:A total of 1,559 individuals (980 newborns and 579 adults) from four participating centers were analyzed by both methods. HemoTypeSC correctly identified 209 of 211 total hemoglobin (Hb) SS cases, for a 99.1%/99.9% total HbSS sensitivity/specificity. Overall, HemoTypeSC exhibited sensitivity and specificity of 98.1% and 99.1% for all possible phenotypes (HbAA, HbAS, and HbSS) detected. HPLC is relatively expensive and not available in most laboratories in remote tribal areas. CONCLUSIONS:We conclude that the rapid, point-of-care testing device HemoTypeSC test is suitable for population and newborn screening for the HbS phenotype.