Implications Of Haemoglobin T. ( HSCT ) - 806 Words

The first successful haematopoietic stem cell transplantation (HSCT) was conducted in 1984. Significant advances have been made since and approximately 1,200 patients have undergone transplantation (Center for International Blood and Marrow Transplant Research, European Society for Blood and Marrow Transplantation personal communication, 2014). SCA is an inherited blood disorder caused by a qualitative mutation in the haemoglobin beta gene (HBB) resulting in an abnormal version known as haemoglobin S (HbS). Typically, normal haemoglobin (HbA) consists of four protein subunits, two alpha-globin and two beta-globin. Replacement of only one beta-globin subunit with HbS results in an asymptomatic heterozygous carrier of the sickle cell trait†¦show more content†¦Screening is usually performed in a newborn blood spot test and the diagnosis is confirmed when electrophoresis demonstrates the presence of homozygous HbS. SCA has been identified as a global public health problem by the World Health Organisation (WHO) and the united nations (UN) with over 5 million affected people worldwide and more than a quarter million live births every year (Piel et al, 2013). The sickle cell gene is prevalent throughout sub-Saharan Africa, the Middle East and regions of the Indian sub-continent with haemoglobin S carrier frequencies ranging from 5% to 40% or more of the population. The WHO has reported around 85% of SCA disorders and over 70% of all affected births occur in Africa. Although SCA modifying therapies such as Hydroxyurea and chronic transfusion are available that have substiantially decreased the symptoms, these therapies do not prevent or reverse any future complications. To date, allogeneic HSCT remains the only curative form of treatment for SCA. A phase 1-2 study was carried out by Hsieh et al (2014) determining the efficacy of nonmyeloablative allogeneic hematopoietic stem-cell transplantation for adults with severe sickle cell disease. Data showed improvement in respective mean hemoglobin levels for females and males as 8.8 ±0.3 and 9.3 ±0.5 g per deciliter before transplantation and 12.6 ±0.6 and 12.7 ±1.1 Nine patients developed long-term, stable donor lymphohaematopoietic engraftment at levels that sufficed to reverse the