Search

We have investigated the effects on platelet function of culture media from 2 sublines of a benzopyrene-induced murine sarcoma (mFS6). Platelet aggregation was investigated according to Born's method. The cell line with greater "in vivo" invasiveness showed higher aggregating activity and higher increase on ADP-induced aggregation; these effects were inhibited by the preincubation of platelets with Aspirin (0,1 mM). These results suggest the role of platelets in metastasis formation; the possibility to inhibit pharmacologically the interactions between platelets and tumour cells could have important implications from both speculative and practical viewpoints.

We have studied bone marrow CFU-GM growth behaviour in 13 patients with Dysmyelopoietic Syndrome by means of the analytical scoring at two sequential times of aggregates. In this way we have distinguished aggregates according to their size, in clusters or colonies and grouped them according to their "in vitro" appearance time, transformation from cluster to colony, "in vitro" survival time and "in vitro" degeneration time. This statement of the study allow us to map CFU-GM subtypes in a percentage distribution related to the total growth of CFU-GM. Comparisons between absolute number of growth of different CFU-GM subtypes in DS vs Normal subjects show both significant and not significant differences, while comparisons between percentages of growth in DS vs Normal subjects did not show significant differences. With this work we suggest an outline for the study and the interpretation of CFU-GM growth patterns in the haematological disorders at risk of evolution in acute nonlymphocytic leukemia.

The effects on platelet function of culture media from 7 human tumours of the gastroenteric tract have been studied on platelet rich plasma obtained from 28 apparently normal subjects. Platelet aggregation was investigated according to Born's method. Some of the culture media showed an aggregating activity on platelets, while others did not; after dialysis, however, also the last ones aggregated platelets. Furthermore all the media both before and after dialysis were able to increase the platelet response to low doses of ADP (3 microM), and these effects were inhibited by Aspirin (0,1 mM). These results suggest that the tumours investigated release stimulating activities on platelet function and that these interactions can be inhibited pharmacologically.

We studied in agar growth behaviour of bone marrow granulocyte-macrophage progenitor cells (CFU-GM) in 16 patients with marrow failure in order to discriminate patients with cells inhibiting granulopoiesis both in bone marrow and peripheral blood. Our experimental design was based on: a) agar culture of bone marrow cells before and after treatment with antilymphocyte globulin (AGL); b) agar co-culture of marrow cells with autologous lymphocytes from peripheral blood. ALG treatment of marrow cells determined CFU-GM growth increase in 4 out of 10 patients; in the same patients co-culture with autologous lymphocytes showed a significant inhibition of CFU-GM growth. The growth enhancement induced by ALG treatment "in vitro" associated with growth inhibition in the coculture suggests the existence of a lymphocyte population suppressing the granulopoiesis both in bone marrow and peripheral blood. With this work we propose an experimental model in order to discriminate marrow failure based on cell-mediated suppression of CFU-GM growth in patient susceptible of immunosuppressive therapy with ALG.

We have studied bone marrow CFU-GM growth behaviour in agar in 7 patients with smouldering Leukemia (SL) in order to test prognostic value of CFU-GM assay to identify patients at high risk of progression to acute nonlymphocytic leukemia (AnLL). By means of the criterion of "topographic scoring at two sequential times", we have estimated bone marrow CFU-GM percentage distribution spectrum, a parameter independent of aggregate absolute number. Basing on our growth data, we have distinguished SL with low colony growth and SL with high cluster growth without colonies. If evaluated quantitatively, these data are not correlated with clinical evolution; if evaluated qualitatively, as percentage distribution spectrum, they are correlated with rapid progression to AnLL. With this work we show that bone marrow CFU-GM distribution spectrum is a suitable parameter to study the disorder of granulocytic line in SL.