Immune-mediated thrombotic thrombocytopenic purpura (iTTP) is characterized by severe ADAMTS13 (a disintegrin and metalloprotease with thrombospondin type 1 repeats, member 13) deficiency, the presence of anti-ADAMTS13 autoantibodies and an open ADAMTS13 conformation with a cryptic epitope in the spacer domain exposed. A detailed knowledge of anti-ADAMTS13 autoantibodies will help identifying pathogenic antibodies and elucidating the cause of ADAMTS13 deficiency. We aimed at cloning anti-ADAMTS13 autoantibodies from iTTP patients to study their epitopes and inhibitory characteristics. We sorted anti-ADAMTS13 autoantibody expressing B cells from peripheral blood mononuclear cells of 13 iTTP patients to isolate anti-ADAMTS13 autoantibody sequences. Ninety-six B cell clones producing anti-ADAMTS13 autoantibodies were identified from which 30 immunoglobulin M (IgM) and 5 IgG sequences were obtained. For this study, we only cloned, expressed and purified the five IgG antibodies. In vitro characterization revealed that three of the five cloned IgG antibodies, TTP73–1, ELH2–1 and TR8C11, indeed recognize ADAMTS13. Epitope mapping showed that antibodies TTP73–1 and TR8C11 bind to the cysteine–spacer domains, while the antibody ELH2–1 recognizes the T2–T3 domains in ADAMTS13. None of the antibodies inhibited ADAMTS13 activity. Given the recent findings regarding the open ADAMTS13 conformation during acute iTTP, we studied if the cloned antibodies could recognize cryptic epitopes in ADAMTS13. Interestingly, all three antibodies recognize cryptic epitopes. In conclusion, we cloned three anti-ADAMTS13 autoantibodies from iTTP patients that recognize cryptic epitopes. Hence, these data nicely fit our recent finding that the conformation of ADAMTS13 is open during acute iTTP.

Conventional pretransfusion testing based on hemagglutination assays can be challenging for patients with autoimmune hemolytic anemia (AIHA) because of the presence of auto-antibodies. It has been suggested that deoxyribonucleic acid-based methods could be more efficient in the selection of antigen-matched red blood cell units in those settings. Because of the high risk of alloimmunization of these patients and the labor-intensive nature of adsorption techniques, we decided to evaluate the feasibility of selecting antigen-matched units on the basis of RBC genotyping. We included in our routine RBC genotyping program samples from 7 patients with AIHA presenting a strongly positive direct antiglobulin test. This made the routine compatibility tests difficult. Most patients had previously received transfusions because of warm AIHA. Matched donor units were selected according to the genotype. For all but 1 patient, blood group genotyping could be done on time to allow antigen-matched transfusion. Four patients received antigen-matched red blood cell units based on RBC genotyping and for 1 patient the fact that no matched units were available led us to postpone the transfusion. After each transfusion, the recovery was recorded and considered satisfactory for all transfused patients.

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Background and ObjectivesThe importance of myocardial dysfunction in sickle cell disease (SCD) is currently debated. It is difficult to find a reliable index of function in patients with chronic overload as in SCD. Speckle tracking echocardiography, a new mean of evaluating cardiac function, might be a useful tool in SCD. It has been applied in many fields to detect early cardiac function deterioration, and it is less load dependent compared with other function parameters. Studies in patients with SCD are rare, and the results are conflicting. The present study aimed to determine whether left ventricular global longitudinal strain (LV-GLS) was abnormal in a population of adults with SCD and whether it was correlated with clinical or biological parameters.MethodsWe prospectively enrolled 37 patients and 34 age- and sex-matched healthy controls. Echocardiography was performed in patients and controls.ResultsWe found that the left ventricular diameter and mass were higher and the ejection fraction and longitudinal strain were lower in patients compared with controls. Diastolic dysfunction was uncommon. LV-GLS was abnormal in 21% of the patients. No correlation was observed between strain and clinical or biological parameters.ConclusionsWe concluded that LV-GLS could be a useful tool for evaluating these patients. However, the clinical impact of reduced LV-GLS remains to be determined.

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Fulvestrant (Faslodex) is a new estrogen receptor (ER) antagonist with no agonist effects that is licensed for the treatment of postmenopausal women with hormone-sensitive advanced breast cancer (ABC) who have progressed/recurred on prior antiestrogen therapy. The Faslodex Compassionate Use Program (CUP) provides expanded access to fulvestrant in countries where it is not yet available for patients who are not eligible to enter clinical trials. This analysis pools data from 402 patients who received fulvestrant as part of the CUP in Belgium, predominantly as 3rd- to 5th-line endocrine therapy for ABC. Two patients experienced partial responses and 118 experienced stable disease lasting>or=6 months, resulting in an overall clinical benefit rate of 29.9%. Fulvestrant was active in patients with multiple sites of metastases, visceral metastases, human epidermal growth factor receptor 2-positive disease and after heavy endocrine pre-treatment. Fulvestrant was well tolerated, with only six patients (1.5%) discontinuing treatment following adverse events. These data support the findings of previous CUP analyses and Phase II and III trials, suggesting that fulvestrant is a valuable addition to the treatment sequence for postmenopausal women with ABC who have progressed/recurred on prior endocrine therapy.

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Despite a moderate prevalence in low-risk myelodysplastic syndromes (MDS) and chronic myelomonocytic leukaemia (CMML), thrombocytopenia remains a risk of severe bleeding and therapeutic options are still limited. There are only a few studies with eltrombopag (ELT), a thrombopoietin receptor agonist, in those patients. In this retrospective multicentre study, ELT was used in 50 patients with MDS and 11 with CMML, with no excess of marrow blasts and platelet counts of <50 9 10 9 / l in a 'real-life' situation. Platelet response occurred in 47 (77%) patients. The median (range) duration of response was 8 (0-69) months. None of the eight still responders who discontinued ELT had relapsed, at a median (range) of 16 (6-23) months after ELT discontinuation. Although 36% of the patients were anti-coagulated or anti-aggregated only 10% of patients had Grade ≥3 bleeding events. Thrombotic events were observed in six (10%) patients, who all but one had a medical history of arterial or venous thrombosis. Progression to acute myeloid leukaemia occurred in four (7%) patients. In this first 'real-life' study, ELT was effective and generally well tolerated in patients with MDS/CMML without excess blasts.