Analysis of genes under the downstream control of the t(8;21) fusion protein AML1-MTG8: overexpression of the TIS11b(ERF-1, cMG1) gene induces myeloid cell proliferation in response to G-CSF

Recurrent transfusion-related acute lung injury

BACKGROUND

Transfusion-related acute lung injury (TRALI) is a rare condition that is commonly associated with the transfusion of donor plasma containing WBC antibodies. Biologically active lipids that accumulate during storage of RBCs and platelets may also cause TRALI. There has been only one previously reported case of recurrent TRALI.

CASE REPORT

A patient received a transfusion 2 days after undergoing hysterectomy; she developed TRALI after receiving the transfusion. The patient recovered after being on ventilation for 6 days but received an additional transfusion and had a second episode of TRALI, which required further ventilation.

RESULTS

Laboratory investigation of the first episode of TRALI suggested the presence of HLA-A2 (N = 1) and granulocyte-specific IgM antibodies (N = 2) in the sera from three of the donors. All three sera reacted in crossmatch studies with the patient's granulocytes and lymphocytes. Lymphocyte-specific IgG antibodies were detected in the patient's serum. There was no evidence to suggest the involvement of WBC antibodies in the second episode of TRALI. Antibody screening of the donors' samples and both forward and reverse crossmatch studies were negative.

CONCLUSION

The first episode of TRALI seems to be due to the action of HLA-A2 and granulocyte-specific IgM antibodies. The second episode may have been due to the action of lipid neutrophil-priming agents in the donors' units in association with the patient's underlying pulmonary condition (i.e., recovering from lung injury). TRALI can recur if a patient requires further transfusion support shortly after an initial episode of TRALI.

The role of the AML1 transcription factor in leukemogenesis

Chromosomal translocations are one of the hallmarks of human leukemias. These structural abnormalities result in the generation of genetic mutations that play a direct role in the transformation of hematopoietic stem cells. Some of the most common targets of these chromosomal rearrangements are the genes that encode the AML1/CBFbeta transcription factor complex. The AML1/CBFbeta complex plays a critical role in normal hematopoiesis, controlling the initiation of a transcriptional cascade required for the formation of definitive hematopoietic stem cells. Understanding how alterations in the normal biologic activity of this transcription factor complex lead to the initiation of leukemia will provide critical insights in the molecular pathogenesis of this disease. These insights in turn are likely to lead to the development of more rational approaches to the treatment of acute leukemia. In this review, we will summarize our current understanding of the mechanisms by which alterations in the activity of AML1/CBFbeta contribute to the development of leukemia.