A comparative study of two routinely used protocols for ex vivo erythroid differentiation.

Background: Erythropoiesis is a complex developmental process in which a hematopoietic stem cell undergoes serial divisions and differentiates through well-defined stages to give rise to red blood cells. Over the last decades, several protocols have been developed to perform ex vivo erythroid differentiation, allowing investigation into erythropoiesis and red cell production in health and disease.

Results: In the current study, we compared the two commonly used protocols by assessing the differentiation kinetics, synchronisation, and cellular yield, using molecular and cellular approaches.

First description of a D-CE-D hybrid gene on a weak D Type 2 molecular background.

Background: RhD phenotypes that express a significantly reduced amount of RhD antigen per red blood cell may be mistyped as RhD-negative by standard serologic methods. The molecular identification of weak D Type 1, 2, or 3 carriers allows managing them as RhD-positive and, thus, rationalizes the use of RhD-negative stock units and the administration of Rh-immunoglobulin prophylaxis, avoiding unnecessary costs and possible side effects.

Study Design And Methods: One sample was investigated for confirming a D-C-E+c+e- phenotype.

New KEL*01M and KEL*02M alleles: structural modeling to assess the impact of amino acid changes.

Background: The KELL antigens are carried by the well-folded and highly polymorphic glycoprotein KELL, belonging to the M13 family of metalloproteases. Anti-KEL, particularly anti-KEL1, are clinically significant. We retrospectively investigated genomic DNA from samples with uncertain KEL1 or KEL2 phenotype and identified six novel Kmod alleles.

A comprehensive survey of both RHD and RHCE allele frequencies in sub-Saharan Africa.

Background: The RH system is one of the most polymorphic blood group systems with numerous allele variants affecting Rh polypeptides expression. This complexity is at the origin of difficulties for transfusion of African patients especially sickle cell disease patients requiring chronic transfusion therapy with high risk of immunization. As a complete survey of RH variants is lacking in African populations, we performed red blood cell genotyping to determine the type and frequency of RHD and RHCE alleles in sub-Saharan African populations.

Heterogeneity of alleles encoding high- and low-prevalence red blood cell antigens across Africa: useful data to facilitate transfusion in African patients.

Ethnic variations in red blood cell (RBC) antigens can be a source of alloimmunization, especially in migrant populations. To improve transfusion safety in continental Africa and countries with African migrants, we performed RBC genotyping to determine allele frequencies coding for high- and low-prevalence antigens. A total of 481 blood samples were collected in ethnic groups from West, Central and East Africa.

Molecular analysis of inactive and active RHD alleles in native Congolese cohorts.

Background: In Africa, RHD alleles have not been fully characterized. The purpose of this study was to identify inactive and active RHD alleles at the molecular level in Congolese cohorts.

Study Design And Methods: Blood samples were collected from people living in central Congo populated by Teke ethnic group.

DNA-based typing of Kell, Kidd, MNS, Dombrock, Colton, and Yt blood group systems in the French Basques.

The Basques demonstrate peculiar characteristics regarding blood group systems. Although ABO, Rhesus, and Duffy have been extensively studied in this population, the distribution of other groups remains largely unknown. Therefore, we evaluated the frequency of less-explored- or still noninvestigated blood groups using DNA-based assays and interpreted these data in the view of population genetics.