PubMed Health⌕ Search

Biomedical subjects

V Gattei

Publications and source records attributed to V Gattei.

49 records · Page 3Linked to original sources
PubMed1992

Follicular lymphoma of compartmentalized small cleaved center cells and mantle zone lymphocytes. Evidence for a common derivation.

The authors have observed a unique case of follicular lymphoma in which the central zones of neoplastic nodules were composed predominantly of small cleaved cells (SCC) that were surrounded by small lymphoid cells proliferating in wide mantles as in mantle zone (MZ) lymphoma. The central SCC component displayed a follicular SCC lymphoma-like phenotype (IgD-, CD10+, CD5-, CD68-), whereas the neoplastic cells of the peripheral zones had an MZ lymphoma-like phenotypic profile (IgD+, CD10-, CD5+, CD68+). In extranodal involved tissues, either follicular or diffuse (leukemic-like) patterns of lymphoma infiltration were noted. Flow cytometric analyses showed in the bone marrow or the peripheral blood two leukemic B cell populations, one mimicking the phenotypic profile (IgM+, IgD+, CD5+, CD10-, Leu8-) of small lymphoid cells with MZ-like features, and the other with phenotypic features (IgM+, IgD-, CD5+, CD10+, Leu8+) intermediate between those of MZ-like cells and those of the SCC component (follicular center-like) detected in the lymph node. Immunomagnetic sorting and gene rearrangement studies indicated that both CD10+ and CD10- B lymphocytes and lymph node neoplastic B cells shared the same clonal origin. This unusual follicular lymphoma can be viewed as the result of the proliferation of a single follicular progenitor capable of differentiating toward both a germinal center and an MZ phenotype. The simultaneous presence in the same patient of at least three neoplastic B-cell populations at different maturation stages, encompassing follicular center and MZ phenotypes, and showing the same clonal derivation, indicates a close lineage relationship between follicular SCC and MZ lymphomas.

Aged↗
PubMed1989

Differential sensitivity to (dl)-5-methyltetrahydrofolate of normal CFU-GM and HL-60 cells.

We studied the effect of (dl)-5-methyltetrahydrofolate on clonogenic growth of HL-60 cells in comparison with human normal CFU-GM. Seven normal bone marrow samples were tested for CFU-GM assay with or without (dl)-mTHF at concentrations ranging from 1.25 X 10(-4) to 5 X 10(-4) M. (dl)-mTHF only slightly affected CFU-GM formation, while, at the same concentrations, it showed a dose related inhibition of HL-60 colony formation, up to a complete arrest of growth at the doses of 5 X 10(-4) and 1 X 10(-3) M. The same impairment of proliferation was observed in liquid culture. These results are in keeping with reported observations, describing a different membrane system mediating "folate" transport in normal and leukemic cells.

Bone Marrow↗
PubMed1989

Induction of differentiation of HL-60 cells along the monocytic pathway by 5-methyltetrahydrofolate.

Many compounds of different chemical structure can induce the HL-60 cell line to differentiate along the monocytic or granulocytic pathway, but the mechanism(s) of differentiation by these agents is not known. Experimental evidence suggests that DNA and/or membrane phospholipid transmethylation reactions may be of importance. Based on this background, we have studied the effects of various concentrations of (dl)-5-methyltetrahydrofolate (mTHF), a folate coenzyme involved in transmethylation reactions, on differentiation of HL-60 cells. Differentiation along the monocytic pathway was evidenced in kinetic, functional, cytochemical and immunophenotypical studies when cells were treated with high-dose (dl)-mTHF (1 x 10(-3)M). Some hypotheses on the mechanism(s) of (dl)-mTHF induced HL-60 cell differentiation are discussed with particular regard to a possible enhancement of lipid or DNA methylation via methionine formation by the (l) form or to inhibition of folate-dependent metabolism by the unnatural (d) form, hence of purine and thymine nucleotide synthesis.

Cell Cycle↗
PubMed1988

Clonogenic growth of acute non-lymphocytic leukemia cells in serum-free medium.

We devised a serum-free medium for growth of leukemic colony-forming units (CFU-L), enriched with albumin, transferrin, lipids, insulin, hydrocortisone and oligoelements. Blast cells from 15 patients affected by acute non-lymphocytic leukemia were grown in this medium in the presence of human placental conditioned medium obtained under serum-free conditions (sfHPCM). Their clonogenic growth was comparable with that obtained in a serum-containing system. Furthermore, when serum-free cultures were carried out in absence of sfHPCM, either CFU-L growth was prevented or, if clones were obtained, the cultures showed a marked decrease in clonogenicity, indicating their strict dependence on growth factors.

Adult↗
PubMed1988

Proliferation and cell loss of human leukemic cell subpopulations in liquid culture.

A kinetic study was performed on leukemic blasts from patients with acute myeloid leukemia, separated into 2 subpopulations by a specific density gradient. The growth curve and the [3H]-thymidine uptake were simultaneously analyzed. While cumulative nucleotide uptake fitted with the growth kinetics in the low-density fraction, such a concordance was not found in the high-density subpopulation. That indicated the occurrence of simultaneous growth and loss in the high density fraction, which could not be evaluated by a simple numerical determination.

Cell Division↗
PubMedDate not supplied

In vitro chemosensitivity testing of leukemic cells: development of a semiautomated colorimetric assay.

A rapid chemosensitivity assay was developed, employing the human continuous leukemic cell lines HL 60, K 562, FLG 29.1. This automated colorimetric assay is based on the characteristic of viable, metabolically active cells to cleave p-iodonitrotetrazolium violet (INT) into a red formazan derivative, whose optical density is readable at 492 nm by an automated microtiter-plate reader photometer. A linear relationship was found between the viable cell number and the optical density of INT cleaved by the cellular samples. Dead cells did not reduce INT and did not interfere with the formazan derivative generation and the photometric reading. Leukemic cell lines were also tested for INT formazan derivative generation after exposure to antileukemic drugs at various concentrations, representative of plasma levels obtainable in vivo. A dose-dependent inhibition was detected, with different sensitivity patterns, related both to the drugs and to the different cell lines. A significant correlation between the viable cell number and the amount of tetrazolium salt cleaved was also demonstrated after drug exposure. INT assay allows the processing of a great number of samples and gives the opportunity to screen several drugs, saving time and yielding fully reliable results.

Autoanalysis↗
PubMedDate not supplied

In vitro chemosensitivity testing of leukemic cells: prediction of response to chemotherapy in patients with acute non-lymphocytic leukemia.

The in vitro chemosensitivity to daunorubicin and cytosine arabinoside of blast cells derived from 35 patients affected by acute non-lymphocytic leukemia was assessed by a semiautomated tetrazolium-based colorimetric assay, by the use of p-iodonitrotetrazolium violet. The results of the in vitro testing were then compared a posteriori to clinical outcome of patients, who followed a schedule of therapy which always included the drugs tested in vitro. Three dosages of drugs were employed to allow the determination of a dose-response curve, which was obtained for all the patients. The data collected in INT assay correlated with the clinical sensitivity of patients, evaluated in terms of achievement of complete remission. For the dosage of ARA-C 500 ng/ml it was possible to establish a significant cutoff between responders and non-responders to therapy, while an acceptable distribution of sensitivity/resistance prediction was found for DNR 500 ng/ml and 5 micrograms/ml. Present results, together with rapid and easy execution of the test, encourage the use of INT assay in screening leukemic patients' sensitivity to antiblastic drugs before treatment or, in case of resistance to classical chemotherapy, in detecting individual sensitivity to alternative drugs.

Adolescent↗