Recipient and donor expression differences in children treated with HSCT

Reconstitution of cell lines and occurrence of complications following hematopoietic stem cell transplantation (HSCT) are regulated by genome expression. Microarray technique allows for simultaneous assessment of expression of nearly all human genes. The objective of the study was to compare whole genome expression in children before and after HSCT. A total of 44 children treated with HSCT were enrolled in the study. Gene expression was measured before HSCT (pre-HSCT group; n=44) and after a median of 6 months after allogenic HSCT (post-HSCT group; n=27; all children were included in the pre-HSCT group). Neoplasms were the indication for HSCT in 73% of the patients. Whole genome expression was assessed in leukocytes using GeneChip HumanGene 1.0 ST microarray. The analysis of genomic profiles before and after HSCT revealed 18 significantly different genes with defined function. These genes are responsible for proliferation and differentiation of cells (14 genes), apoptosis (8 genes), migration of cells (3 genes) and fluid/electrolyte homeostasis (2 genes). Our findings allow us to conclude that activation of genes involved in reconstitution of donor cell lines, and those related to immune reactions observed after HSCT, form the genetic background for physiological and pathological processes following HSCT.

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