[Bilateral primary renal Burkitt lymphoma presenting with acute renal failure].

We report the case of a 12 year-old girl who presented with acute renal failure with massive infiltration in both kidneys due to a Burkitt lymphoma that was diagnosed by percutaneous renal biopsy. This case fulfilled all the diagnostic criteria of Malbrain et al. to be considered as primary renal non-Hodgkin lymphoma.

Potential for cytokine and product manipulation to improve the results of autologous stem cell transplantation for rheumatoid arthritis.

The eradication of autoreactive T cells by high dose therapy and stem cell transplantation and the resultant alterations in the immunologic network, thymic reeducation, and peripheral tolerance provide treatment mechanisms for autoimmune and inflammatory diseases. One outcome of autologous stem cell transplantation is a significant decrease in the CD4:CD8 ratio due to a loss in CD4+ cells and a depression in T cell function. Mechanistically, the loss of T cell function is associated with an increased frequency of circulating monocytes, their expression of Fas ligand (FasL), and a high frequency of apoptotic CD4+ T cells.

Activation-induced T cell apoptosis by monocytes from stem cell products.

We recently found that mobilized peripheral blood stem cell (PSC) products (from both cancer patients and normal donors) contain high levels of CD14+ monocytes, which can inhibit the proliferation of allogeneic and autologous T cells. We found in our studies that using CD14+ monocytes from mobilized PSC products (from normal and cancer patient donors), normal apheresis products or normal peripheral blood (PB) can affect lymphocyte function and apoptosis-dependent T cell activation. However, it appears that the apoptosis is dependent on the frequency of monocytes, which is increased by both mobilization and apheresis.

Mechanisms of immune dysfunction in stem cell transplantation.

High dose therapy (HDT) and stem cell transplantation (SCT) results in alterations in the immunologic network, thymic re-education and the induction of peripheral tolerance. The changes to the immunoregulatory cascade and tolerance induction associated with autotransplants have been investigated in a series of studies focused on leukocyte reconstitution and function following HDT and autologous SCT. In these studies, we observed a significant decrease in the CD4:CD8 T cell ratio post-transplantation compared to normal peripheral blood (PB) donors due to a decrease in CD4+ cells.

Growth factor mobilization and modulation of progenitor cell adhesion to stromal cells: role of VLA-4.

Cellular interactions between hematopoietic progenitor cells and bone marrow (BM) stromal cells are mediated by cell adhesion molecules (CAM). In agreement with previous studies, our flow cytometric analysis of isolated CD34+ cells showed that VLA-4 expression was significantly (p < 0.001) higher on steady-state BM than on CD34+ cells from growth factor-mobilized peripheral stem cell (PSC) products.