[Donor chimerism and minimal residual disease monitoring in leukemia patients after allo-HSCT]. / Monitoring donorskogo khimerizma i minimal'noi ostatochnoi bolezni u onkogematologicheskikh bol'nykh posle allogennoi transplantatsii gemopoéticheskikh stvolovykh kletok.

In present research the comparative analysis of donor chimerism (DC) using different tests was performed to improve the diagnostic tool in patients with malignant hematological disorders after allo-HSCT. The RBC antigen typing, identification of ABO blood type and quantitative analysis of InDel-, STR-, Y-polymorphisms were carried out for detection of DC. In addition, the expression of well-known oncogenes and CD-markers for monitoring MRD was evaluated to predict relapse and clinical outcome. According to our research, the analysis of InDel polymorphism using AlleleSEQR-PCR is more sensitive test for estimation of DC as compared with other assays. Moreover, the sensitivity of AlleleSEQR-PCR may be increased after isolation of the CD34 cell population in bone marrow. Nevertheless, observation of high levels in DC (³95%) in some leukemia patients (ALL, Ph+, bcr-abl/p190+) during first 6 months after HSCT cannot exclude the possibility of relapse. Thus, the combined monitoring of both DC (InDel) and MRD (oncogenes, WT1 and CD-markers) is a more advisable and useful test in managing hematologic malignancies and predicting relapse risk after allo-HSCT.

Cloning and characterization of the human FCRL2 gene.

We report cloning and characterization of FCRL2, a novel human gene that belongs to the FcR family. The gene is closely linked and structurally similar to the recently identified FCRL/FREB/FcRX gene. The encoded protein is composed of three Ig-like domains and a C-terminal mucin-like domain containing a conserved alpha-helical motif with dileucine signals. Intraexonic splicing may generate two alternative transcripts, coding for isoforms with the third and fourth domains replaced by entirely different amino acid sequences. Like FCRL, the full-length isoform of FCRL2 is expressed intracellularly in transfected 293T cells. Expression analysis revealed FCRL2 mRNA only in placenta. The gene transcripts were not detected in lymphoid tissues or in the main leukocyte subsets isolated from peripheral blood. However, we found that FCRL2 is differentially expressed by transformed B cell lines. Of interest is also the finding that the gene expression may be up-regulated in the progression of melanocytic tumors.