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P052
88
P052
Abstracts / Human Immunology 75 (2014) 50–141
HLA GENE MUTAGENESIS CAUSED BY TUMOR BLAST CELLS IN PERIPHERAL BLOOD.
Weicheng Zhao, Edward Guerrero, Dana Willis, Kai Cao. UT MD Anderson Cancer Center, Houston, TX, United States. Aim: Since SBT technologies were applied in HLA typing, more and more new nucleotide mutations have been being identified and reported as new HLA alleles. However, some of the nucleotide mutations may not exist in the patient’s somatic cells, but (but or because) they are caused by tumor blast cells in the peripheral blood. If so, should the typing results be reported as new alleles? In this study, we present three cases in which nucleotide mutations were found in the whole blood from leukemia patients, but not in their buccal cells. Methods: DNAs were isolated from peripheral whole blood (PB) specimens, and buccal specimens separately, as needed. Sequencing-based typing (SBT) was performed by using locus/group/allele specific primers to separate the heterozygous alleles. Results: Initial SBT results with DNAs from PB showed case #1 carries HLA -B⁄14:02:01, 18:01:01 with 1 mutation in codon 203.1 (from TGC to YGC) and the patient with AML had 47% blasts in PB; Case #2 carries HLA-B⁄44:02:01 with 1 additional ‘‘A’’ in codon 171.3 (from TAC to TAM) and the patient with CML had 59% blasts in PB; and case #3 carries HLA-A⁄02:01:01 with 1 additional ‘‘T’’ in codon 96.1 (from CAG to YAG) and the patient with lymphoma had 71% abnormal lymphocytes with irregular nuclei. None of these patients had previous transplant history. Confirmatory SBT results with DNAs from buccal cells indicate that none of those nucleotide mutations above exist (Table 1). Conclusions: The accurate HLA typings are crucial to the outcome of stem cell transplantation. Whenever an unusual HLA typing from peripheral blood of a cancer patient is identified, the result of blood differentials should be checked and the confirmatory testing with buccal specimen should be followed.
P052
Abstracts / Human Immunology 75 (2014) 50–141
HLA GENE MUTAGENESIS CAUSED BY TUMOR BLAST CELLS IN PERIPHERAL BLOOD.
Weicheng Zhao, Edward Guerrero, Dana Willis, Kai Cao. UT MD Anderson Cancer Center, Houston, TX, United States. Aim: Since SBT technologies were applied in HLA typing, more and more new nucleotide mutations have been being identified and reported as new HLA alleles. However, some of the nucleotide mutations may not exist in the patient’s somatic cells, but (but or because) they are caused by tumor blast cells in the peripheral blood. If so, should the typing results be reported as new alleles? In this study, we present three cases in which nucleotide mutations were found in the whole blood from leukemia patients, but not in their buccal cells. Methods: DNAs were isolated from peripheral whole blood (PB) specimens, and buccal specimens separately, as needed. Sequencing-based typing (SBT) was performed by using locus/group/allele specific primers to separate the heterozygous alleles. Results: Initial SBT results with DNAs from PB showed case #1 carries HLA -B⁄14:02:01, 18:01:01 with 1 mutation in codon 203.1 (from TGC to YGC) and the patient with AML had 47% blasts in PB; Case #2 carries HLA-B⁄44:02:01 with 1 additional ‘‘A’’ in codon 171.3 (from TAC to TAM) and the patient with CML had 59% blasts in PB; and case #3 carries HLA-A⁄02:01:01 with 1 additional ‘‘T’’ in codon 96.1 (from CAG to YAG) and the patient with lymphoma had 71% abnormal lymphocytes with irregular nuclei. None of these patients had previous transplant history. Confirmatory SBT results with DNAs from buccal cells indicate that none of those nucleotide mutations above exist (Table 1). Conclusions: The accurate HLA typings are crucial to the outcome of stem cell transplantation. Whenever an unusual HLA typing from peripheral blood of a cancer patient is identified, the result of blood differentials should be checked and the confirmatory testing with buccal specimen should be followed.