Significance Of Expression Of CD133Subgroup Molecules In B-lineage Childhood Acute Lymphoblastic Leukemia And Its Biological Characteristics In Vitro

1、 Clinical significance of expression of CD133molecules in acutelymphoblastic leukemiaObjective To explore relationship between the expression of CD133and clinicalprognostic factors in childhood acute lymphocytic leukemia (ALL) before and afterinduction chemotherapy.Methods1) Expression of CD133-1/CD133-2from bone marrow (BM) MNC wasanalysed by using flow cytometry in59cases of newly diagnosed ALL.Results1) There was no relevance between expression of CD133and gender，age,white blood cells count, percentage of bone marrow blast cells, lactate dehydrogenase（LDH） level, cytogenetics, fusion gene, risk stratification, complete remission （CR）rate and the experation of CD38、CD58、CD66c in childhood B-ALL(P>0.05).2)Expression of CD133-1in21cases of B-ALL was positive (38.2%), expression ofCD133-2in30cases was positive (54.5%), and there was significant difference betweenexpression of CD133-1and that of CD133-2(P <0.05).3) The expression of CD34andCD133had significant difference in B-ALL (P <0.05),while there was no significantcorrelation between them (P>0.05).Conclusions1)There was no relevance between expression of CD133and gender，age,white blood cells count, percentage of bone marrow blast cells, LDH level, cytogenetics,fusion gene, risk stratification, CR rate and the expression of CD38、CD58、CD66c inchildhood B-ALL.2)Compared to CD133-1, the expression of CD133-2molecule washigher than that of CD133-1.3)There was no correlation between expression of CD133 and that of CD34.2、Preliminary study of biological characteristics of CD133+cells fromB-ALLObjective Explore the biological characteristics of CDl33+CD19+and CDl33+CD19-cells from childhood B-ALL in vitro.Methods Bone marrow (BM) MNCs with positive expression of CD133from4casesof B-ALL were sorted and CDl33+CD19+and CDl33+CD19-subgroup cells werecollected by using magnetic active cell sorting (MACS).The two subgroups were cluteredin serum-free medium supplemented with different cytokine. Cultured cells’ characteristicsin week from4to7were evaluated by RT-PCR or flow cytometryResults1)Total number of recycling cells were （76.9±25.63）×106, which is lowerthan the number（99.0±21.07）×106） befor sorting,but there is no significant differencebetween them (P>0.05).The total recovery rate was77.7%, and the recovery rate ofCDl33+CD19+and CDl33+CD19-cells were4.11%,15.4%respectively.The purity ofsorted cells was analysed by flow cytomety, and the average purity for CDl33+CD19+andCDl33+CD19-were （77.5±13.61）%and (76.83±5.58)％respectively.2) CDl33+CD19+and CDl33+CD19-cells were capable of forming tumor spheres in serum-free medium.,CDl33+CD19+cells proliferate faster than CD133+CD19-cells at different four time.There is no significant difference between them (P>0.05).While the CD133-CD19+andCD133-CD19-cells cannot form tumor spheres.3) After the serum-free culture of average5weeks,there was no experasion of CD133and CD19.4)2cases which have abnormalgene expression (TEL/AML1and MLL/AF4express positive) at diagnosis showed thesame gene expression after the serum-free culture.Conclusion1) MACS can separate and purify CD133+CD19+and CD133+CD19-cells in vitro.2) Proliferation and biological characteristics of CD133+cells from B-ALLcan be effectively maintained in vitro in serum-free medium supplemented with differentcytokines.3）Compared to CD133-cells, CDl33+cells owned better proliferation capacity.CD133+CD19+cells maybe had leukemic stem cells properties.