Anomalous leukopoiesis in two patients with Crohn's disease.

Crohn's disease is a major form of chronic inflammatory bowel disease in the western world. The molecular genetic basis of Crohn's disease is unknown. In this study, we present evidence for anomalous leukopoiesis-namely, the generation of a leukocyte subset characterized by aberrant expression of gammadelta T cell receptor (gammadeltaTCR) with or without CD19 on a myeloid background-in two patients with Crohn's disease.

Engraftment of human T-cell acute lymphoblastic leukemia in immunodeficient NOD/SCID mice which have been preconditioned by injection of human cord blood.

Childhood T-cell acute lymphoblastic leukemia (T-ALL) is one of the most common childhood cancers. Study of leukemia biology, as well as preclinical testing of potential therapeutic regimens directed at T-ALL, has been impeded by the lack of an efficient in vivo model of primary leukemia. We have reported elsewhere some observations that human cord blood conditioned medium enhances leukemia colony formation in vitro and preconditioning of sublethally irradiated nonobese diabetic/ severe combined immunodeficient (NOD/SCID) mice with cord blood mononuclear cells (MNCs) facilitates the subsequent engraftment of primary T-ALL cells in these mice.

Preconditioning with fetal cord blood facilitates engraftment of primary childhood T-cell acute lymphoblastic leukemia in immunodeficient mice.

Childhood T-cell acute lymphoblastic leukemia (T-ALL) is one of the most common childhood cancers. It is reported that preconditioning sublethally irradiated immunodeficient NOD/SCID (nonobese diabetic/X-linked severe combined immunodeficient) mice with human cord blood mononuclear cells facilitates the engraftment, expansion, and dissemination in these mice of primary T-ALL cells obtained from patients at the time of diagnosis. Cells recovered from mouse bone marrow or spleen resembled the original leukemia cells from patients with respect to surface lineage markers and T-cell receptor Vbeta gene rearrangements.

Human cord blood conditioned medium enhances leukemia colony formation in vitro.

Childhood T-cell acute lymphoblastic leukemia (T-ALL) is one of the most common childhood cancers. Recently, we observed that pre-conditioning sub-lethally irradiated immunodeficient mice with human cord blood mononuclear cells facilitates in these mice high level engraftment of primary T-ALL cells obtained from patients. Here we report that human cord blood cells secrete a factor(s) which markedly enhances in vitro both colony number and burst size of the T-ALL clonogenic progenitors from patients.