ABSTRACT
Objective To develop a method of isolation and identification of exosomes of bone marrow mesenchymal stem cells.Methods The mesenchymal stem cells were cultured by whole bone marrow adherence method.A new reagent -exosomes extraction kit was used to isolate and collecte exosomes.The exosomes were identified by elec-tron microscopy,particle size detection,flow cytometry and Western blot.Results The expression of CD45 on the surface of the third generation bone marrow mesenchymal stem cells was negative,and CD73 and CD105 were posi-tive;exosomes derived from bone marrow mesenchymal stem cells were round or oval,the size is non-uniform,the diameter is 30~100 nm,have a complete membrane structure,and containing low-density substances;Particle size detection particle diameter of the main peak was 61.25 nm, in which the diameter of particles was about 20-200 nm accounted for 72.4%;exosome expressed CD63 and CD81;The expression of CD9 and CD63 from cell cul-ture supernatants was positive.Conclusions The exosomes can be collected in the medium of mesenchymal stem cells.The exosomes derived from bone marrow mesenchymal stem cells can be identified by electron microscopy, particle size detection,flow cytometry and Western blot.
ABSTRACT
<p><b>OBJECTIVE</b>To investigate the hematological characteristics of co-inheritance of α-thalassemia (α-thal) and β-thalassemia (β-thal) and to survey the incidence of co-inheritance of α-thal and β-thal in Guangxi.</p><p><b>METHODS</b>DNA samples from 370 primary and middle school students who were β-thal carriers in Guangxi were further processed for the α-goblin gene mutation screening, and were grouped based on the genotype of β- and α-goblin gene. The hematological indexes to the different groups were compared by One-way ANOVA.</p><p><b>RESULTS</b>Of the total 370 β-thal carriers, 79 were found to carry α-thal, which gave a frequency of 21.35% for β-thal carriers and 1.36% for coincidence of these two common disorders in the local population. As expected, the 79 patients presented very variable α-globin alterations in combination with β-globin mutations, showing 31 genotype combined with the coincidence of both Hb disorders. Except the genotypes of 3 β-thal heterozygotes combined with ααα(anti3.7) triplication and 2 β-thal carriers with IVS-II-654(C→T)/N combined-α(3.7)/αα presented the phenotype of thalassemia intermedia, and other 74 carriers with co-inheritance of α-thal and β-thal all presented the phenotype of β-thal trait. There were significant differences between β-thal heterozygotes and the carriers with a co-inheritance of both β+α(0) thal in MCH, MCV and Hb. In addition, there existed significant difference between the carriers with a co-inheritance of both β+α(+) thal and a co-inheritance of both β+α(0) thal in MCV, MCH and Hb.</p><p><b>CONCLUSION</b>Compared to that of β-thal heterozygotes, the carriers with a co-inheritance of α-thal and β-thal had slighter phenotype with hematological characteristics. It's difficult to distinguish the double heterozygotes with the co-inheritance of α-thal and β-thal from β-thal heterozygotes by hematological indexes, the molecular diagnosis should be performed.</p>