Association of homocysteine and inflammatory-related molecules in sickle cell anemia.

OBJECTIVE: Investigate the role of homocysteine (Hcy), Th17-related cytokines, and adhesion molecules in the inflammatory state seen in the sickle cell anemia (SCA). METHODS: We studied the Hcy, interleukin (IL)-17, and transforming growth factor ß (TGF-ß) cytokine levels of 62 SCA patients, as well as the expression levels of inflammatory and endothelial activation markers. RESULTS: We found significant associations between Hcy levels and increased expression of IL-17 and TGF-ß among SCA patients, and a positive significant correlation between Hcy and soluble vascular cellular adhesion molecules (sVCAM). SCA individuals had raised IL-17 levels when compared with controls. DISCUSSION: These results suggest a possible role of Hyc in the induction of TGF-ß and IL-17. Other authors proposed that Hcy may contribute to the initiation and progression of vascular disease by monocyte activation, resulting in the secretion of cytokines that amplify the inflammatory response. The role of Hcy in cytokine production and oxidative stress in the endothelium may explain the increase of sVCAM expression and, the vascular activation currently described among the SCA individuals with the highest Hcy serum levels. The chronic inflammation was observed in hyperhomocysteinemic mice, with an increased expression of VCAM-1 and plasma levels of tumor necrosis factor-alpha, showing an association of this inflammatory molecule and vascular changes. CONCLUSION: Our findings suggest that the increased levels of IL-17,Hcy and sVCAM contributes contributes to the vascular inflammation and activation presented by SCA patients, which probably have an important role in vaso-occlusion. On the basis of the presented data, IL-17 and Hcy might be considered as important components in the pathogenesis of SCA.

Alloimmunization and clinical profile of sickle cell disease patients from Salvador-Brazil.

Sickle cell disease (SCD) is an important public health issue in Bahia, Brazil. Erythrocyte transfusions may reduce morbidity of SCD, however, they are associated with numerous risks. Among other risk categories, alloimmunization to red cell antigens may result from transfusions. The aim of this study was to compare the clinical profile of transfused adult SCD patients with and without alloantibodies. The study included 108 patients (105 homozygous SS and three with hemoglobinopathy SC), followed in the Outpatient Unit of the Hematology and Hemotherapy Center of Bahia. A retrospective review of clinical records of adult SCD patients who received at least three red blood cell transfusions from 2004 to 2007 was performed. Transfusion units were phenotypically matched for ABH-D and C,c,E,e, and K antigens. Alloimmunization developed in 56 patients (53 SS and three SC). The most prevalent alloantibodies were anti-E, anti-K, and anti-C (39.3%, 21.4%, and 16.1%, respectively). Age, sex and positive antiglobulin test displayed statistically significant differences. Prevalence of clinical complications such as leg ulcers, stroke, and others did not show differences between groups. In conclusion, alloimmunization did not significantly modify the clinical outcomes of SCD patients from Bahia, Brazil.