Sweet's syndrome: association with accelerated phase of chronic myeloid leukemia

The authors describe a case of Sweet's syndrome in a woman affected with chronic myeloid leukemia. They emphasize the association of the syndrome with a progression of the disease and the complete disappearance of it for 3 years until the present time after allogeneic bone marrow transplantation.

Membrane receptors for interleukin 2 on hematopoietic precursors in chronic myeloid leukemia

In this report we present data on the expression of IL2 receptors on chronic phase CML cells. Using an anti IL2 receptor monoclonal antibody (McAb aIL2r) in indirect immunofluorescence we found significant proportions (42.2% +/- 19.7 SD) of the CML cells (previously depleted of E rosetting T cells) to be IL2 receptor positive following incubation in suspension for 18 hours at 37 degrees C. Noninduced cells did not express IL2 receptors. After induction the aIL2r positive and negative cell subpopulations were sorted and analyzed separately for morphology, lineage specific cell surface markers, and clonogenic cell numbers. The IL2 receptor positive CML subpopulations mainly contained blast cells and monocytes and revealed reactivity with myeloid McAbs but not with T cell, B cell, platelet, or erythroid markers. Clonogenic cells (CFU-GEMM, BFUe, and CFU-GM) were selectively recovered from aIL2r positive CML cells and thus were IL2 receptor positive. The addition of recombinant IL2 (rIL2) to CFU-GM and BFUe cultures, in concentrations from 50 to 500 U/mL, did not influence the efficiency of colony formation. Binding of a radiolabeled IL2 preparation to the in vitro activated CML cells indicated the presence of low affinity receptors for IL2. In contrast to CML, normal human marrow cells were consistently aIL2r nonreactive. Thus, IL2 receptor inducibility is a characteristic feature of CML clonogenic cells, which they share with AML, but not with normal marrow progenitors. The role of IL2 receptors in the regulation of proliferation of CML cells requires further investigation.

High-dose therapy followed by autologous bone marrow transplantation (ABMT) in previously untreated non-Hodgkin's lymphoma

13 previously untreated patients with poor prognosis non-Hodgkin's lymphoma (NHL) underwent high-dose therapy followed by autologous bone marrow transplantation (ABMT). All patients experienced a great cytoreductive effect and 9 of them reached a complete remission (mean duration 32 months). The best results were observed in patients with more limited disease and in those without symptoms. 7 patients still remain in complete unmantained remission 15-46 months from the transplant. The probability of survival is 74% at 46 months. No therapy-related deaths were recorded. In differentiating our preliminary approach, we propose high dose therapy followed by ABMT as induction phase in patients with stage II and as consolidation after first line therapy in patients with stages III-IV. Further studies are warranted to determine which type of lymphoma may benefit more and which conditioning regimens may improve the remission rate.

Stromal cells in primary myelofibrosis: ultrastructural observations

The bone marrows of five patients with primary myelofibrosis at different stages of the disease have been studied. In the myelofibrotic bone marrow, associated with "reticulum cells", two other cell types have been identified, namely fibroblast-like and myofibroblast-like reticulum cells, as well as a spectrum of transitional forms. Our findings suggest that reticulum cells may represent a reserve stromal cell pool (i.e. primitive reticulum cells) able to modulate themselves and to transform differently according to functional requirements. Some suggestions regarding the functional significance of fibroblast-like and myofibroblast-like reticulum cells in primary myelofibrosis are suggested.

Recovery of CFU-GM after freezing of normal human bone marrow: effect of three dilution techniques after thawing

In the cryopreservation procedures intended for autotransplantation of human bone marrow a controversial point is represented by the methods of reconstruction of the cellular suspension after thawing and before infusion into the patient. To evaluate how the dilution rate after thawing affects bone marrow viability, we cryopreserved the bone marrow from 16 hematologically normal patients in DMSO at a concentration of 10%. After thawing, the cells were diluted according to three different techniques and their viability was tested by the growth of CFU-GM in methylcellulose. The average recovery of CFU-GM, in comparison with that of fresh cells, was satisfactory and not affected by the type of dilution. In conclusion, if we accept that the resistance to osmotic stress due to the cryoprotectant is similar for stem cells and CFU-GM, we can maintain that a slow, gradual dilution is not a necessary condition to assume the staminality of bone marrow designed for autotransplantation.

[Ribostamycin in chronic and recurrent bronchopulmonary and urinary infections]

Results in the treatment of mostly Gram-negative infections of the respiratory apparatus (30 subjects) and the urinary apparatus (20 subjects) with ribostamycin are reported. These were regarded as good overall, as shown by the bacteriological findings. An extremely high sensitivity to the antibiotic was noted in isolated germs from both types of infection. This good response in vitro was matched by an equally encouraging bacteriological result in vivo.