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Biomedical subjects

G Piaggio

Publications and source records attributed to G Piaggio.

At least 109 records · Page 6Linked to original sources

Insulin-induced phosphorylation of the beta-4 integrin subunit expressed on murine metastatic carcinoma cells.

A tumor surface protein (TSP-180) that is highly expressed on highly malignant metastatic cells has been identified on murine lung carcinomas. On SDS-PAGE under reducing conditions, TSP-180 shows a complex banding pattern corresponding to 204, 183, 150, 135, and 116 kDa. All bands of the TSP-180 complex are glycosylated and are labeled by lactoperoxidase-catalyzed radioiodination of viable cells. The mouse TSP-180 complex described here is homologous to the human integrin alpha 6 beta 4 complex, and in particular it has been demonstrated that protein corresponding to 204 kDa is homologous to the beta 4 subunit of the integrin complex. It has been shown recently that monoclonal antibody to TSP-180 (MoAb 135-13C) stimulates cell growth in vitro and induces phosphorylation of the 204-kDa protein. We now report that insulin increases the phosphorylation of the 204-kDa protein 30-fold in intact carcinoma cells and epidermal growth factor (EGF) causes a threefold increase. Insulin-like growth factor (IGF-I) and platelet-derived growth factor have no effect. The effect of insulin and of IGF-I on phosphorylation of their own receptors was studied using solubilized cell membranes. Insulin and IGF-I each induced a fivefold increase in the phosphorylation of their respective receptor beta subunits. In order to test if phosphorylation of the 204-kDa protein was induced by direct binding of growth factors to TSP-180 and to identify growth factor receptors on line 1 cells, affinity cross-linking studies were performed. Affinity labeling of receptors demonstrated that insulin and IGF-I both bind to a 135-kDa protein that corresponds to the insulin and IGF-I receptor alpha subunits. Affinity labeling of EGF receptors failed to demonstrate EGF receptor molecules (175-kDa protein) on line 1 cells. Further investigations by using a different approach confirmed the very low amount of EGF receptors on line 1 cells. Direct phosphoamino acid analysis of the 204-kDa protein purified from insulin-stimulated cells demonstrated that this beta 4 integrin subunit is phosphorylated on serine and tyrosine. We conclude that beta 4 integrin molecule is a target for phosphorylation through an indirect receptor-mediated mechanism.

Amino Acids↗

Effect of antilymphocyte globulin (ALG) on bone marrow T/non-T cells from aplastic anaemia patients and normal controls.

UNLABELLED: The aim of this study was twofold: (a) to test the effect of antilymphocyte globulin (ALG) on bone marrow (BM) T/non-T cells, and (b) to look for a possible differential response of cells from severe aplastic anaemia (SAA) patients and controls. For this purpose bone marrow T/non-T cells from normal individuals (n = 7) or aplastic patients (SAA, n = 13) were kept in liquid culture with or without ALG. Supernatants were then tested for enhancement/suppression on colony forming unit, granulocyte-macrophage (CFU-GM) growth (in the presence of exogenous recombinant granulocyte-macrophage colony stimulating factor (rGM-CSF)), or for their ability to support CFU-GM growth (in the absence of exogenous rGM-CSF). Supernatants from SAA T cells suppressed CFU-GM growth of normal bone marrow cells in 5/12 patients (mean expected growth (EG) 71 +/- 16%), but not after incubation with ALG (mean 110 +/- 29% EG, P = 0.03). No inhibition could be obtained with the supernatants from untreated normal T cells. Significant enhancement was seen with ALG treated versus untreated SAA T cells (142 +/- 28% EG v. 105 +/- 61% EG, P = 0.01) and with ALG treated versus untreated SAA non-T cells (165 +/- 26% EG v. 105 +/- 23% EG, P = 0.01), but not in controls. Supernatants from SAA and control T/non-T cells were capable of promoting colony formation in the absence of rGM-CSF (colony-stimulating activity (CSA) production): 16 +/- 14% for SAA-T cells and 19 +/- 18% EG for non-T cells (100% = 30 ng rGM-CSF/ml). The addition of ALG increased CSA production in T cells to 37 +/- 23% EG (P = 0.04) and in non-T cells to 40 +/- 13% EG (P = 0.04). Similar results could be obtained in controls. IN CONCLUSION: (a) ALG interacts in vitro with bone marrow T and non-T cells from SAA patients, down-regulating the production of negative lymphokines and enhancing the release of haemopoietins; (b) the latter, but not the former effect, can be shown also with cells from normal controls. The two effects are not mutually exclusive, and are likely to provide maximal benefit in vivo.

Anemia, Aplastic↗

T cells and myeloid progenitors in patients with severe aplastic anemia (SAA).

This report summarizes some of our past and present studies on T cells and hemopoietic progenitors obtained from patients with severe aplastic anemia (SAA). Two main issues are discussed: enhancement of colony growth by manipulation of accessory cells, or by the addition of patients' plasma, and the role of suppressor T cells in the pathogenesis of the disease and response to antilymphocyte globulin (ALG). A complex network of interactions exists. The identification of cells and soluble factors capable of enhancing or suppressing colony formation promises to help us better understand the events leading first to the development of aplasia and then eventually to hematologic recovery.

Anemia, Aplastic↗

Human serum-dependent survival of GM-CFCs in vitro from patients with chronic granulocytic leukemia.

Bone marrow (BM) cells from 15 patients with chronic granulocytic leukemia (CGL) and 12 normal donors were placed in liquid culture for 4-7 days in the presence of fetal calf serum (FCS) or human AB serum. BM cells were plated in agar for GM-CFC growth at day 0, day 4, day 7 of culture, in the presence of human placenta conditioned medium (HPCM). The recovery of GM-CFCs on day 4 in FCS was 86 +/- 18 and 15 +/- 18% from normal or CGL BM cells respectively (p = 0.005). The recovery of GM-CFCs on day 4 in human AB serum was comparable for normal (66 +/- 48%) and CGL (69 +/- 32%) BM cells. Similar results were obtained on day 7 of culture. Cytochemical staining of agar plates showed a sharp drop of macrophage colonies in CGL BM cells kept in FCS cultures on day 4-7, when compared to both normal BM cells and baseline colonies. These data suggest that the survival in liquid culture of GM-CFCs from patients with CGL is dependent on a factor present in human and not in fetal calf serum. This is not the case for normal GM-CFCs.

Animals↗

Aplastic anemia: pathogenesis and treatment.

Treatment of severe aplastic anemia (SAA) in Europe between 1970 and 1986 is reviewed. 487 patients received an HLA-identical BMT: results are encouraging and currently suggest a 65% survival. However, many patients cannot be offered this procedure because of the absence of an appropriate donor. Forty-five patients were given a non-HLA identical BMT: results are dependent on the degree of mismatch. Immunosuppression (IS) was given to 509 patients: 50% of these survive. Some mechanisms regulating in vitro hematopoiesis are discussed, together with their relevance in the treatment of SAA.

Anemia, Aplastic↗

Bone marrow transplantation for chronic granulocytic leukemia.

Thirty patients with chronic granulocytic leukemia (CGL), were given cyclophosphamide 60 mg/kg on each of 2 consecutive days, followed by total body irradiation (TBI) 10 Gy and an HLA-identical bone marrow transplant (BMT). Eleven patients were in the accelerated phase of their disease (CGLacc) or in second/secondary chronic phase (CGL-2CP), with a median age of 33 years: four patients died of transplant related complications, and four of recurrent leukemia; three patients are alive and well 19, 31, 33 months from BMT. The actuarial 33-month survival is 27%. The actuarial relapse rate is 50%. Nineteen patients were in their first chronic phase (1CP), with a median age of 32 years: three died of graft versus host disease (GvHD), two of infection, and two of acute respiratory distress syndrome (ARDS); 12 are alive and well 6 to 29 months post-BMT. The actuarial 29-month survival is 63%. The actuarial survival of patients younger than 30 years is 63%, compared to 62% for patients older than 30 (P = 0.1). The survival of patients grafted within or after 24 months from the onset of CGL is respectively 87% and 45% (P = 0.04). None of the patients grafted in 1CP had a true hematologic-cytogenetic relapse. The Ph' chromosome was detected on one occasion in two patients 12, 13 months post-BMT: they both remain hematologically normal and Ph1-negative 3 to 6 months later, after discontinuation of cyclosporin A. This study confirms that survival exceeding 60% can be obtained in CGL in the first chronic phase, whereas less than 30% of patients will survive if grafted in accelerated, second/secondary chronic phase, mainly because of leukemic relapse. The duration of the disease seems to be relevant to the outcome of the transplant. The effect of post-transplant immunosuppression, in our case cyclosporin A, on the interaction between normal and Ph1-positive hemopoietic cells, may deserve further attention.

Adolescent↗

Competitive survival/proliferation of normal and Ph1-positive haemopoietic cells.

Bone marrow (BM) cells from 10 patients with Ph1-positive chronic granulocytic leukaemia (CGL) were placed in long-term cultures in the presence of fetal calf serum (FCS) and horse serum (HoS), or in the presence of human AB serum. The long-term cultures were started with three different cell combinations: (1) CGL BM cells (four cases), (2) CGL BM cells + normal BM cells (1:1 ratio) from an HLA identical sex-matched sibling (five cases), (3) CGL BM cells + normal BM cells (1:1 ratio) from an HLA identical sex mismatched sibling (five cases). Cytogenetic studies were performed at weeks 0, 3, 4 and 5 of culture. The results of this study can be summarized as follows: (a) Ph1-positive cells could be detected at any time of culture in all three of the described cell combinations; (b) a population of Ph1-negative cells of patient origin could be detected after 3-5 weeks of culture; (c) there was a trend for a better survival of Ph1-negative cells in cultures supplemented with FCS + HoS and, conversely, of Ph1-positive cells in cultures containing human serum. These results warrant further studies on the possibility of manipulating survival and proliferation of normal and leukaemic cells by varying the culture conditions.

Bone Marrow↗

In vitro tests in severe aplastic anaemia (SAA): a prospective study in 46 patients treated with immunosuppression.

Forty-six patients with severe aplastic anaemia (SAA) were studied for CFU-c growth on admission and 1 month post-treatment with immunosuppression (IS). Twenty-three patients became transfusion independent after IS, and were considered responders, and 23 did not. CFU-c growth from unfractionated bone marrow cells was comparable in both groups on admission and 1 month post-treatment. CFU-c growth from E rosette depleted BM cells (E-BM) was also comparable on admission. However, 1 month post-treatment, responders showed a significantly higher CFU-c growth (P = 0.02) from E-BM cells compared to non-responders. At the same time 7/8 responders studied showed T cell mediated suppression of autologous CFU-c growth. T cell depletion experiments do not give predictive information on the outcome of IS therapy on admission. They may, however, be helpful to identify responders early post-treatment.

Adolescent↗

Cyclosporin A (CyA) does not enhance CFU-c growth in patients with severe aplastic anaemia.

8 patients with severe aplastic anaemia (SAA) in remission following immunosuppressive therapy were studied for CFU-c growth from unfractionated or E-rosette depleted (E-) bone marrow (BM) cells. Cyclosporin A (CyA) was added to unfractionated BM cells at a concentration of 1000 ng/ml. The mean number of CFU-c/10(5) BM cells plated was 6 +/- 6 from unfractionated BM cells, 28 +/- 20 from E-BM cells, and 8 +/- 7 from unfractionated BM cells supplemented with CyA. All patients had significant increase of CFU-c growth after E rosette depletion (overall P = 0.002). On the contrary, only 1 patient showed an increase of CFU-c growth after addition of CyA, and overall there was no difference between untreated and CyA treated BM cells (P = 0.7). These results suggest that addition of CyA to BM cells in vitro is not an effective means of enhancing CFU-c growth in SAA patients.

Adolescent↗

Bone marrow transplantation (BMT) for acute nonlymphoid leukemia (ANLL) in first remission.

20 patients with acute nonlymphoid leukemia (ANLL) in first remission were given cyclophosphamide, 120 mg/kg, followed by total body irradiation (TBI) and an HLA-identical allogeneic marrow transplant (BMT). TBI was delivered in a single dose (10 Gy on day -1) in 2 patients, or in fractionated doses (3.3 rad/day on days -3, -2, -1) in 18 patients. The median age of patients was 22 years (range 2-44). Median time from remission to BMT was 5 months (range 1-12). 5 patients died of transplant-related toxicity (graft-versus-host disease with or without interstitial pneumonia) and 15 are alive 7-77 months post-BMT (median 20). The actuarial 72 months survival is 73%. There has been one relapse in a 2-year-old child, 4 months post-BMT, in the marrow and in the testis. The 72-month actuarial disease-free survival is 68%. The actuarial probability of relapse is 7%. This study indicates that a high proportion of ANLL patients treated in first remission with fractionated TBI and allogeneic marrow transplantation can become long-term disease-free survivors.

Acute Disease↗

T-derived colony-inhibiting activity: partial characterization and mechanism of action.

A soluble inhibitor of granulocyte macrophage colony growth, to which we shall refer to as T-derived colony-inhibiting activity (Td/CIA), was obtained from the supernatant of T cells from 5 healthy donors and 5 patients with severe aplastic anemia (SAA) in remission, following immunosuppressive therapy. The supernatants were purified by an ACA 44 column and the suppressor activity found in fractions of 70,000-80,000 daltons. Experiments were then performed to test for endogenous productions of Td/CIA in normal marrow cells (NBM), reversibility of suppression, and competitive inhibition with human placenta-conditioned medium (HPCM). The results of this study can be summarized as follows: the endogenous production of Td/CIA can be elicited by addition of mitogens to NBM, and is prevented if the marrow is T-depleted or treated with cyclosporin A; suppression is completely reversible if Td/CIA is removed from NBM by washing at 1, 48, 72 and 96 h; CFU-c which have been exposed to Td/CIA once, and freed from Td/CIA by washing, are still sensitive to a second exposure of Td/CIA; there is no clear competitive inhibition between Td/CIA and HPCM. These experiments represent an in vitro model of a lymphokine-mediated regulation of CFU-c growth not associated with death of progenitor cells.

Bone Marrow Cells↗

Effect of cyclosporin A (CyA) on the in vitro growth of hemopoietic progenitors from normal marrow.

Unfractionated normal bone marrow cells (NBM), adherent-cell-depleted NBM, and E-rosette-depleted NBM were plated in vitro for CFU-c or BFU-E formation at plateau concentrations of colony-stimulating activity (CSA) or erythropoietin, untreated or after preincubation with cyclosporin A (CyA). At concentrations of 1000 or 2000 ng/ml, CyA enhanced CFU-c growth up to 137 +/- 32% and 147 +/- 31% of expected baseline growth respectively (p = 0.005 and 0.001). When CyA was added to NBM depleted of T cells by rosetting once with sheep red blood cells (SRBC) there was no CFU-c enhancement at CyA concentrations of 1000 ng/ml, but enhancement could be seen at 2000-5000 ng/ml. The enhancing effect of CyA was completely abolished, however, when the SRBC rosetting procedure was repeated twice (95 +/- 37% of expected growth). On the other hand, removal of adherent cells was without effect on CFU-c enhancement mediated by CyA. The addition of CyA to NBM also enhanced the growth of BFU-E (256 +/- 182% of expected growth) (p = 0.001). The results of this study suggest that CyA can increase the plating efficiency of NBM cells, possibly by inhibiting an endogenous, T-cell-mediated, suppressor mechanism.

Bone Marrow Cells↗

Cytochemical analysis of peripheral blood mononuclear cells following allogeneic bone marrow transplantation: correlation of hydrolase expression with graft-versus-host disease.

Peripheral blood mononuclear cells of 21 patients undergoing allogeneic bone marrow transplantation (BMT) were monitored post-BMT for immunologic markers (E rosettes OKT3, OKT8, DR, and BT5/9, a monoclonal antibody which stains helper T cells), cytochemical markers (acid phosphatase [AP], beta-glucuronidase [BGLU], and acid alpha naphthyl acetate esterase [ANAE] ), and morphology. The cytochemical T score, was obtained from typical AP, BGLU, and ANAE reactivity. The same was done for the cytochemical non-T score and macrophage (Mo) score. All patients received cyclosporine A (CyA) for graft-v-host disease (GvHD) prophylaxis. In univariate analysis there was no significant correlation between the proportion of E rosettes, OKT3-, OKT8-, DR-, and BT5/9-positive cells, and GvHD. The first three showed instead a positive correlation with time from transplant: E rosettes (P = .02), OKT3 (P = .01), and OKT8 (P = .003). In contrast, a significant negative correlation was found in univariate analysis, between the cytochemical T score and GvHD (P = .0001), and a positive correlation between non-T score and GvHD (P = .0008), as well as between the Mo score and GvHD (P = .03). There was no influence of time from transplant on the T (P = .8), non-T (P = .8), or Mo score (P = .4). In multivariate analysis comparing E rosettes, OKT3, T score, non-T score, GvHD, and time from BMT, the only variable associated with GvHD was the T score (P less than .05). These results suggest that T cell activation during GvHD is associated with a loss of hydrolase expression in T cells, but does not imply relevant modifications of immunologic surface markers. In addition, lysosomal enzymes appear early (before day 10) after transplantation, indicating that T cells at this stage are well differentiated.

Anemia, Aplastic↗