Cord blood stem cell banking and transplantation

ABO and Rh (D) blood group phenotype distribution pattern among blood donors at the Nekemte Blood Bank, Oromia, West Ethiopia: a retrospective cross-sectional study

OBJECTIVE

To determine the distribution of ABO and Rh (D) blood group phenotypes among blood donors.

METHODS

This retrospective cross-sectional study enrolled blood donors whose socio-demographic and blood group phenotype data were collected from blood bank donor records. Descriptive statistics were used to summarise the number and percentage distribution of categorical variables. To determine if the distributions of the ABO and Rh phenotypes differed, a chi-square test was employed.

RESULTS

Of 14,887 blood donors with a median age of 20 years (interquartile range = 18-30 years), 72.8% were males, and young donors (age range = 18-24 years) accounted for 61.7%. Group O (45.6%) was the most prevalent ABO blood phenotype, followed by A (29.5%), B (20.2%), and AB (4.7%). The dominant blood group was O positive (42.4%), followed by A positive (27.4%), B positive (18.9%), AB positive (4.3%), O negative (3.2%), A negative (2.1%), B negative (1.3%), and AB negative (0.4%). The overall Rh (D)-negative distribution rate was 7.0%.

CONCLUSION

This study showed that blood group O was the most common ABO phenotype, followed by A, B, and AB. Overall, 93.0% of the donors were Rh (D)-positive. These findings may help guide blood transfusion programmes.

Phenotype, Allele and Genotype Frequency of ABO and Rhesus D Blood Groups of Blood Donors at the North Gondar District Blood Bank, Northwest Ethiopia

Background

Knowledge of the ABO and RhD group distribution is essential for blood banks inventory and assuring quality blood transfusion services. The objective of this study was to determine the frequency of ABO and RhD phenotype, allele, and genotype among blood donors at North Gondar District Blood Bank from 2010 to 2012, Northwest Ethiopia.

Methods

The data of the current study were obtained from registration logbooks of blood donors registered. The ABO and RhD grouping was done by using commercially available monoclonal antibodies (anti-A, anti-B and anti-D) by slide methods. Results with no agglutination by anti-D antibody were confirmed using anti-human globulin test. Descriptive statistics were analyzed using SPSS version 20. The allele and genotype frequency of the donors was determined by Hardy–Weinberg equilibrium assumption. The difference between the observed and expected frequency was tested by online Chi-square calculator. P-value of <0.05 was considered statistically significant.

Results

Among 6471 blood donors, 82.1%, 94.1% and 55.4% were males, replacement donors and in the age group of 21–30 years, respectively. Blood group O (47.04%) and blood group AB (4.81%) were the dominant and least common, respectively. The distribution of the RhD negative blood group was 5.76%. The distribution of A, B and O alleles was 0.1714, 0.1433 and 0.6859, respectively. Moreover, the genotype frequency of AA, AO, BB, BO, AB and OO was 0.0294, 0.2350, 0.0205, 0.1966, 0.0491 and 0.4704, respectively. The genotype frequency of DD, Dd and dd was 0.5774, 0.3649 and 0.0576, respectively. The result showed that there was no statistically significant difference between observed and expected allele and genotype frequency (P-value >0.05).

Conclusion

Blood group O and AB were the most and least prevalent, respectively. The allele and genotype frequency of the population was fulfilled the Hardy–Weinberg equilibrium assumption. This finding might be useful for blood transfusion services.

Microfluidics as efficient technology for the isolation and characterization of stem cells

The recent years have been passed with significant progressions in the utilization of microfluidic technologies for cellular investigations. The aim of microfluidics is to mimic small-scale body environment with features like optical transparency. Microfluidics can screen and monitor different cell types during culture and study cell function in response to stimuli in a fully controlled environment. No matter how the microfluidic environment is similar to in vivo environment, it is not possible to fully investigate stem cells behavior in response to stimuli during cell proliferation and differentiation. Researchers have used stem cells in different fields from fundamental researches to clinical applications. Many cells in the body possess particular functions, but stem cells do not have a specific task and can turn into almost any type of cells. Stem cells are undifferentiated cells with the ability of changing into specific cells that can be essential for the body. Researchers and physicians are interested in stem cells to use them in testing the function of the body's systems and solving their complications. This review discusses the recent advances in utilizing microfluidic techniques for the analysis of stem cells, and mentions the advantages and disadvantages of using microfluidic technology for stem cell research.

Biohybrid hematopoietic niche for expansion of hematopoietic stem/progenitor cells by using geometrically controlled fibrous layers

Biohybrid hematopoietic niche for expansion of hematopoietic stem/progenitor cells.

Stem cells in microfluidics

Microfluidic techniques have been recently developed for cell-based assays. In microfluidic systems, the objective is for these microenvironments to mimic in vivo surroundings. With advantageous characteristics such as optical transparency and the capability for automating protocols, different types of cells can be cultured, screened, and monitored in real time to systematically investigate their morphology and functions under well-controlled microenvironments in response to various stimuli. Recently, the study of stem cells using microfluidic platforms has attracted considerable interest. Even though stem cells have been studied extensively using bench-top systems, an understanding of their behavior in in vivo-like microenvironments which stimulate cell proliferation and differentiation is still lacking. In this paper, recent cell studies using microfluidic systems are first introduced. The various miniature systems for cell culture, sorting and isolation, and stimulation are then systematically reviewed. The main focus of this review is on papers published in recent years studying stem cells by using microfluidic technology. This review aims to provide experts in microfluidics an overview of various microfluidic systems for stem cell research.

An integrated microfluidic system for isolation, counting, and sorting of hematopoietic stem cells

This study reports an integrated microfluidic system capable of isolation, counting, and sorting of hematopoietic stem cells (HSCs) from cord blood in an automatic format by utilizing a magnetic-bead-based immunoassay. Three functional modules, including cell isolation, cell counting, and cell sorting modules are integrated on a single chip by using microfluidic technology. The cell isolation module is comprised of a four-membrane-type micromixer for binding of target stem cells and magnetic beads, two pneumatic micropumps for sample transport, and an S-shaped channel for isolation of HSCs using a permanent magnet underneath. The counting and sorting of HSCs are performed by utilizing the cell counting and sorting modules. Experimental results show that a separation efficiency as high as 88% for HSCs from cord blood is achieved within 40 min for a sample volume of 100 mul. Therefore, the development of this integrated microfluidic system may be promising for various applications such as stem cell research and cell therapy.