Anti-HBB (native protein) polyclonal antibody

Beginning early in childhood, patients with sickle cell disease [SCD; a group of genetic haemoglobin disorders characterized by the sickle or HbS mutation (HBB E7V)] are at risk of life-threatening and debilitating health events. Despite the high morbidity and mortality of this disease, haematopoietic cell transplantation (HCT), a curative therapy for SCD, remains underutilized. A variety of factors, including the limited availability of suitable donors, play a role in this trend, but do not fully explain the low frequency with which this therapy is employed. The objective of this study was to identify paediatric haematologists' attitudes about HCT as a treatment option for SCD, and to describe the impact of these attitudes on their practices of discussing HCT with families of children affected by this disease. A nationwide survey of paediatric haematologists in the United States was conducted between February and May 2016. Two hundred and eighty-seven surveys were included in the final analysis (response rate 20%). On average, respondents reported informing 42% of families about HCT as a treatment option (N = 248, 95% confidence interval: 38-46). Clinician attitudes about the cost and safety of HCT were associated with practices of discussing this therapy with families. These findings suggest that clinician attitudes and referral practices may play a role in the underutilization of this therapy in the SCD population.

Background Human genetic factors are important determinants of malaria risk. We investigated associations between multiple candidate polymorphisms-many related to the structure or function of red blood cells-and risk for severe Plasmodium falciparum malaria and its specific phenotypes, including cerebral malaria, severe malaria anaemia, and respiratory distress. Methods We did a case-control study in Kilifi County, Kenya. We recruited as cases children presenting with severe malaria to the high-dependency ward of Kilifi County Hospital. We included as controls infants born in the local community between Aug 1, 2006, and Sept 30, 2010, who were part of a genetics study. We tested for associations between a range of candidate malaria-protective genes and risk for severe malaria and its specific phenotypes. We used a permutation approach to account for multiple comparisons between polymorphisms and severe malaria. We judged p values less than 0.005 significant for the primary analysis of the association between candidate genes and severe malaria. Findings Between June 11, 1995, and June 12, 2008, 2244 children with severe malaria were recruited to the study, and 3949 infants were included as controls. Overall, 263 (12%) of 2244 children with severe malaria died in hospital, including 196 (16%) of 1233 with cerebral malaria. We investigated 121 polymorphisms in 70 candidate severe malaria-associated genes. We found significant associations between risk for severe malaria overall and polymorphisms in 15 genes or locations, of which most were related to red blood cells: ABO, ATP2B4, ARL14, CD40LG, FREM3, INPP4B, G6PD, HBA (both HBA1 and HBA2), HBB, IL10, LPHN2 (also known as ADGRL2), LOC727982, RPS6KL1, CAND1, and GNAS. Combined, these genetic associations accounted for 5.2% of the variance in risk for developing severe malaria among individuals in the general population. We confirmed established associations between severe malaria and sickle-cell trait (odds ratio [OR] 0.15, 95% CI 0.11-0.20; p=2.61 x 10(-58)), blood group O (0.74, 0.66-0.82; p=6.26 x 10(-8)), and -alpha(3.7)-thalassaemia (0.83, 0.76-0.90; p=2.06 x 10(-6)). We also found strong associations between overall risk of severe malaria and polymorphisms in both ATP2B4 (OR 0.76, 95% CI 0.63-0.92; p=0.001) and FREM3 (0.64, 0.53-0.79; p=3.18 x 10(-14)). The association with FREM3 could be accounted for by linkage disequilibrium with a complex structural mutation within the glycophorin gene region (comprising GYPA, GYPB, and GYPE) that encodes for the rare Dantu blood group antigen. Heterozygosity for Dantu was associated with risk for severe malaria (OR 0.57, 95% CI 0.49-0.68; p= 3.22 x 10(-11)), as was homozygosity (0.26, 0.11-0.62; p=0.002). Interpretation Both ATP2B4 and the Dantu blood group antigen are associated with the structure and function of red blood cells. ATP2B4 codes for plasma membrane calcium-transporting ATPase 4 (the major calcium pump on red blood cells) and the glycophorins are ligands for parasites to invade red blood cells. Future work should aim at uncovering the mechanisms by which these polymorphisms can result in severe malaria protection and investigate the implications of these associations for wider health. Copyright (C) 2018 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license.