Diagnosis of retinoblastoma in a presymptomatic stage after detection of interstitial chromosomal deletion 13q.

In a newborn with only minor malformations the finding of an extended interstitial chromosome deletion 13q was unexpectedly found [46,XY,del(13) (q14.11q22.2)]. The included deletion of chromosome band 13q14, which is known to be predisposing for retinoblastoma (Rb), gave rise to subsequent ophthalmological inspection. A multifocal tumor was detected immediately in the right eye and 11 months later contralaterally. In contrast to the Knudson hypothesis, which suggests a high risk of a multifocal and bilateral tumor in patients with an inherited mutation of the RB-1 gene, literature data indicate a reduced tumorigenesis in patients with a cytogenetic deletion of the critical Rb region of chromosome 13. However, the authors' patient shows that even with a cytogenetic deletion early, bilateral, and multifocal tumor formation is possible. Reliable risk estimates of tumorigenesis for patients with a chromosome deletion cannot be given, since most of these were ascertained by their tumor.

Method dependency of blood group determination after bone marrow transplantation.

After minor-incompatible bone marrow transplantation (e.g. recipient A, donor 0), red cells are donor-type but absorb recipient-type AB0 substance from plasma. Because of discrepant results, we tested how such cells type with standard methods. In the tube test 7 of 8 patients showed donor type. In Diamed AB0 gel, weak-positive reactions were found with anti-AB in the patients (donor 0) tested. Commercial AB0 antibodies from different companies used in Diamed neutral gel trays differed widely in the results obtained. The strongest positive reactions were found with polyclonal anti-AB. The exact antibody and technique are crucial to the result of AB0 typing after minor-incompatible bone marrow transplantation.

[Effect of tumor necrosis factor on human hematopoietic precursor cells]. / Untersuchungen über die Wirkung von Tumornekrosefaktor auf humane hämatopoetische Vorläuferzellen.

The effect of human recombinant tumor necrosis factor (rhTNF-alpha) on the in vitro colony growth of normal hematopoietic progenitor cells was investigated. In a clonal colony-assay a dose-dependent inhibition of erythroid BFU-E, granulocyte/monocyte CFU-GM and megakaryocyte CFU-Mk was demonstrated. CFU-Mk were completely inhibited by low doses of TNF-alpha (3 U-300 U/ml). 50% inhibition occurred at 10 U/ml of TNF for CFU-Mk, 100% inhibition at 300 U/ml of TNF. 50% inhibition occurred at 233 U/ml of TNF for CFU-GM, and 100% inhibition for CFU-GM was not observed. For inhibition of BFU-E higher doses of TNF-alpha were necessary (100 U-1,000 U/ml). The growth inhibitory effect could selectively be abolished by antibodies against TNF-alpha. Removal of adherent cells and T-lymphocytes from the bone marrow cells had no significant influence of the suppressive effect of TNF-alpha. The inhibitory effect of TNF-alpha is due to a direct action on hematopoietic progenitor cells and not mediated by accessory cells.

Inhibitory effect of azidothymidine, 2'-3'-dideoxyadenosine, and 2'-3'-dideoxycytidine on in vitro growth of hematopoietic progenitor cells from normal persons and from patients with AIDS.

Therapy of patients with the acquired immunodeficiency syndrome (AIDS) or AIDS-related complex (ARC) with azidothymidine (AZT) and 2'-3'-dideoxycytidine (ddC) is complicated by severe anemia, neutropenia, and thrombocytopenia, the cause of which is unknown. We therefore tested the effect of AZT, ddC, and an additional 2'-3'-dideoxynucleoside analogue, 2'-3'-dideoxyadenosine (ddA), on the hematopoietic progenitor cells derived from the bone marrow of normal persons and patients with AIDS/ARC. All three substances dose-dependently inhibited the in vitro colony formation of the pluripotent (CFU-GEMM), as well as the erythroid (BFU-E) and granulocyte-macrophage progenitor cells (CFU-GM). The 50% inhibition of normal progenitors by AZT occurred at 0.13 microM for CFU-GEMM, 0.32 microM for BFU-E, and 1.9 microM for CFU-GM, by ddA at 15 microM for CFU-GEMM, 40 microM for BFU-E, and 140 microM for CFU-GM. ddC was the most toxic agent and already inhibited 71% +/- 16% (mean +/- standard error of the mean [SEM]) of CFU-GEMM and 52% +/- 22% of BFU-E at 0.1 microM, whereas the 50% inhibition of CFU-GM was reached at 0.3 microM. Hematotoxicity occurred at concentrations lower than necessary to inhibit the human immunodeficiency virus (HIV), except for ddA, which is 100 times less toxic than AZT whereas its antiviral effect is only 10 times less. The inhibition of progenitor cells from AIDS patients by the 2'-3'-dideoxynucleosides was comparable to normal progenitors, except for a higher sensitivity of AIDS-derived CFU-GEMM and BFU-E to AZT.

Recombinant human granulocyte-macrophage colony-stimulating factor in patients with myelodysplastic syndromes--a phase I/II trial.

In a phase I/II study, 11 patients with myelodysplastic syndromes (MDS) and severe transfusion-dependent cytopenia were treated with recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) to investigate the effects of rhGM-CSF on normal hematopoiesis and leukemic cells. The treatment schedule included dose escalation from 15 micrograms/m2 to 150 micrograms/m2 administered by continuous intravenous (IV) infusion for seven to 14 days and was repeated after a two-week treatment-free interval. The blood leukocyte counts increased dose dependently by 130% to 1,800% in ten patients; a rise of monocytes and eosinophils occurred in seven and six patients, respectively. No sustained increase in reticulocytes or platelets was observed. Lymphocyte counts increased in all patients affecting both T-helper and T-suppressor cells; however, the lymphocytes were not activated as analyzed by the expression of the interleukin-2 receptor. In four of the patients, all with greater than 14% blast cells in the bone marrow, the percentage of bone marrow blast cells increased during treatment with rhGM-CSF. Cytogenetic data indicated induction of both proliferation and differentiation of the leukemic clones by rhGM-CSF. Toxic side effects were minor with slight fever, phlebitis at the infusion site, and bone pain in the minority of patients. In conclusion, rhGM-CSF effectively stimulates hematopoiesis in vivo in patients with myelodysplastic syndromes. However, as the leukemic cell population can be stimulated in patients with a higher initial blast cell count, the combination of rhGM-CSF with other differentiation-inducing or cytotoxic agents has to be considered.

Phase I/II study with GM-CSF in patients with myelodysplastic syndromes.

The availability of rh GM-CSF has allowed the in vivo treatment of patients with cytopenia. Therefore a phase I/II trial was initiated to study the effect of rh GM-CSF in patients with myelodysplastic syndromes who were not eligible for other kinds of therapy. rh GM-CSF has been tested in 10 patients in doses from 15 micrograms/m2 to 150 micrograms/m2 given intravenously over 8 hours for a cycle of 7 days followed by an interval of 14 days and a second 7-day treatment course. A dose dependent increase in leukocyte count was observed in 9 out of 10 patients. No change in reticulocyte numbers was seen and only one patient experienced an increase in platelet count. Toxicity mainly consisted of mild local phlebitis at the site of infusion and sternal pain after bolus injection. An increase in blast cell counts in some patients necessitated the start of low dose Ara-C therapy.

Effect of recombinant human granulocyte-macrophage colony-stimulating factor on the hemopoietic progenitor cells from patients with AIDS.

Derangement of the hemopoietic progenitor cells has been observed in the majority of patients with the acquired immunodeficiency syndrome (AIDS). In this study the effect of recombinant human GM-CSF was evaluated for the in vitro growth of hemopoietic progenitor cells from the bone marrow of patients with AIDS. A significant reduction of growth (mean +/- SEM) of CFU-GEMM (2.5 +/- 1.2), BFU-E (23 +/- 9), and CFU-GM (55 +/- 21) was found in AIDS patients in comparison to normal controls. There was a linear correlation between the number of CFU-GM growing in vitro after stimulation with rh GM-CSF as compared to medium conditioned by phytohemagglutinin-stimulated leukocytes (PHA-LCM). However, CFU-GM from patients with AIDS appear to need higher concentrations of rh GM-CSF for maximal growth.

Recombinant human granulocyte-macrophage colony-stimulating factor in patients with myelodysplastic syndromes--a phase-I/II trial.

A phase-I/II trial was initiated to study the effect of rhGM-CSF in patients with myelodysplastic syndromes who were not eligible for other kinds of therapy, rhGM-CSF was given to 9 patients in doses of 15 micrograms/m2-150 micrograms/m2 as an intravenous 8-h infusion for a cycle of 7 days followed by an interval of 14 days and a second 7-day treatment course. A dose-dependent increase in the leukocyte count was observed in 7 out of 9 patients. No change in reticulocyte numbers was seen and only 1 patient experienced an increase in platelet count. Toxicity mainly consisted of mild local phlebitis at the site of infusion and sternal pain after bolus injection.

In vitro and in vivo action of recombinant human GM-CSF (rhGM-CSF) in patients with myelodysplastic syndromes.

The availability of rhGM-CSF has allowed the in vivo treatment of patients with cytopenia. Therefore, a phase I-II trial was initiated to study the effect of rhGM-CSF in patients with myelodysplastic syndromes who were not eligible for other kinds of therapy. rhGM-CSF has been tested in 10 patients in doses from 15 micrograms/m2 to 150 micrograms/m2 given intravenously over 8 hours for a cycle of 7 days followed by an interval of 14 days and a second 7-day treatment course. A dose-dependent increase in leukocyte count was observed in 9 of 10 patients. No change in reticulocyte numbers was seen and only one patient experienced an increase in platelet count. Toxicity mainly consisted of mild phlebitis at the site of infusion and sternal pain after bolus injection. An increase in blast cell counts in some patients necessitated the start of low-dose Ara-C therapy.

Effect of recombinant interferons alpha and gamma on human bone marrow-derived megakaryocytic progenitor cells.

Interferons (IFNs) have been shown to suppress the proliferation of human pluripotent hematopoietic progenitor cells, CFU-GEMM, and committed erythroid (BFU-E, CFU-E) and granulocyte-macrophage (CFU-GM) progenitor cells. However, no information is yet available concerning the effect of IFNs on human megakaryocytic progenitor cells CFU-Mk. Furthermore the mechanisms underlying the inhibitory activity of IFNs are still controversial. Therefore highly purified recombinant IFN preparations, rIFN-alpha and rIFN-gamma, were assessed for their influence on in vitro growth of human bone marrow-derived CFU-Mk as well as CFU-GEMM. In addition, the role of hematopoietic accessory cells, that is, adherent cells and T lymphocytes, in the mediation of the suppressive effect of rIFNs was examined. When added to unseparated bone marrow cells, both rIFN preparations significantly inhibited colony formation with 50% inhibition of CFU-Mk occurring at 22 U/mL for rIFN-alpha and 59 U/mL for rIFN-gamma, while 50% inhibition of CFU-GEMM occurred at 59 U/mL for rIFN-alpha and 101 U/mL for rIFN-gamma. The suppressive effect of rIFN-alpha and rIFN-gamma was selectively abolished by monoclonal antibodies (MoAbs) against rIFN-alpha and rIFN-gamma, thus confirming that the inhibitory activity was due to the rIFN preparations used. The antiproliferative effect of rIFN-alpha and rIFN-gamma on CFU-GEMM growth was not associated with a decrease in the percentage of mixed colonies containing megakaryocytic cells as assessed by use of the MoAb C17.28 against platelet glycoprotein IIIa. Removal of adherent cells and T lymphocytes from the target bone marrow cells had no influence on the suppressive effect of rIFN-alpha, whereas it significantly reduced the inhibitory effect of rIFN-gamma on the growth of megakaryocytic colonies and the other hematopoietic progenitors. The data indicate that (1) human megakaryocytopoiesis is markedly inhibited by rIFN-alpha and rIFN-gamma, and (2) the inhibitory effect of rIFN-alpha is due to a direct action on hematopoietic progenitor cells, whereas the effect of rIFN-gamma is mediated to a significant degree through accessory cell populations.