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Biomedical subjects

G Basso

Publications and source records attributed to G Basso.

At least 163 records · Page 9Linked to original sources
PubMed1986

Molecular and immunological evidence of B-cell commitment in "null" acute lymphoblastic leukaemia.

The DNA configuration of the immunoglobulin (Ig) heavy and light chain genes and the expression of B-cell-related markers were evaluated in 13 cases of non-T, non-B, non-common ("null") acute lymphoblastic leukaemia (ALL). A rearrangement of the Ig heavy-chain gene was found in all cases studied; in 5 of these a structural reorganization of the kappa or lambda light chain gene was also demonstrated. Leukaemic cells from 10 of the 13 cases analysed showed one or more B-cell antigens, the expression of which followed a sequential order of presentation (OKB2, B4, BA-1, B1). The B-cell commitment was confirmed by means of a sensitive immunoperoxidase assay which revealed a weak expression of the common ALL (cALL) antigen in 7/10 cases tested, which were all cALL-negative by conventional immunofluorescence techniques. These findings suggest that in "null" ALL the neoplastic cells show molecular and immunological evidence of B-cell differentiation and that most cases may indeed be characterized by "early" cALL with a very low density expression of the cALL antigen. This was further documented in one case in which the expression of the cALL antigen (and of other B-cell markers) could be induced after exposure to 12-O-tetradecanoylphorbol-13-acetate (TPA). The presence in a few cases of myeloid features, particularly when the cALL antigen could not be demonstrated by the immunoperoxidase assay, suggests that the leukaemic process may sometimes involve a very early progenitor cell capable of both lymphoid and myeloid phenotypic differentiation. The heterogeneity of "null" ALL documented by this study may help to explain the variable clinical course and prognosis of these patients.

Antigens, Neoplasm↗
PubMed1985

Immunocytochemical evidence of common-ALL antigen in null-ALL.

4 cases of acute lymphoblastic leukaemia (ALL), diagnosed as null-ALL by indirect immunofluorescence using monoclonal antibodies, were similarly investigated using a sensitive immunoperoxidase method. The Avidin-Biotin system was employed. The immunoenzymatic results were in agreement with those obtained with immunofluorescence techniques for all antigens except common-ALL (C-ALL). The C-ALL antigen, recognized by the J5 antibody, was detected only by the immunoperoxidase method on cell membranes of the 4 ALL. This paper discusses the possibility of false negative results in testing for C-ALL antigen by conventional indirect immunofluorescence as suggested by refined immunocytochemical screening. Moreover, the ability of the immunoperoxidase system to identify antigens on cell membranes, even at very low density, is discussed. The clinical significance of the presence of C-ALL antigen at weak intensity in cases of null-ALL is also considered.

Antibodies, Monoclonal↗
PubMed1984

Non-T, non-B childhood acute lymphoblastic leukemia. Correlation between cytochemical markers and first complete remission.

The positivity for four cytochemical reactions, acid phosphatase (AcP), alpha-naphtyl acid acetate esterase (ANAE), beta-glucuronidase (BG), and N-acetyl beta-glucosaminidase (NABG) was correlated to first remission duration in 120 children affected with non-T, non-B acute lymphoblastic leukemia (ALL). The percentages of patients remaining in complete remission at 72 months were always higher for children whose blasts lacked these enzymatic reactions; however, a statistical difference was found only between BG+ and BG- ALL. It also appears that more complete enzymatic patterns of leukemic cells are associated with a poorer prognosis. The percentage of patients still in their first remission was 89% for leukemias with no cytochemical markers, 59% when one reaction was present, but less than 39% when two or more enzymes were detected in the blasts. It is noteworthy that the blasts of patients with more severe prognosis demonstrated a simultaneous positivity for AcP-ANAE or BG-NABG cytochemical reactions. The possible usefulness of these cytochemical markers to detect subsets of patients with different prognostic significance among non-T, non-B ALL is discussed.

Acid Phosphatase↗
PubMed1984

Characterization of two patients with lymphomas of large granular lymphocytes.

Two patients with non cutaneous well-differentiated lymphocytic lymphoma with leukemic spread are reported. The large majority of their peripheral blood mononuclear cells (PBMC) formed rosettes with sheep erythrocytes, had receptors for the Fc portion of IgG, and an enzymatic profile of relatively mature T-cells. These cells were morphologically characterized as large granular lymphocytes. Studies with monoclonal antibodies in one of the cases showed an OKT3+, OKT10-, OKT4-, OKT8-, HNK-1-, OKM1+ phenotype, whereas PBMC from the other case were OKT3+, OKT10-, OKT4-, OKT8+, HNK-1+, OKM1-. PBMC from the first patient were able to suppress in vitro B-cell differentiation and were capable of a strong antibody dependent cellular cytotoxicity (ADCC) activity. Natural killer (NK) activity was reduced. Cells from the other patient who was hypogammaglobulinemic, exerted suppressor activity in immunoregulatory assays, and showed ADCC and NK activity. These data support the existence of LGL lymphomas consisting of the proliferation of mature appearing cells capable of functional activity.

Antibodies, Monoclonal↗
PubMed1981

Cytochemical study in human lymphocyte subpopulations as defined by Fc receptors.

Three subpopulations of human T lymphocytes (TG, TM, and Tnon-G/non-M cells) were evaluated by means of six different cytochemical reactions. Elevated staining activity was demonstrated in all the populations when stained for acid phosphatase (AcP), beta-glucuronidase (BG) and N-acetyl beta-glucosaminidase (NABG). While the majority of TM cells displayed an intense acid alpha-naphthyl acetate esterase (ANAE) positivity, only a smaller proportion of the Tnon-G/non-M exhibited a positive reaction and a much lower activity was found in the TG group. TM cells were also alpha-naphthyl acetate esterase (NAE)-and alpha-naphthyl butyrate esterase (NBE)-positive, showing a dot-like pattern. These reactions were present in a lower proportion in the Tnon-G/non-M population and nearly completely absent in the TG cells. The present study identifies different cytochemical phenotypes for the different T-lymphocyte subsets and the analysis of these phenotypes may indicate that the TM is the most cytochemically differentiated subpopulation.

Acetylglucosaminidase↗
PubMed1980

Cytochemical study of thymocytes and T lymphocytes.

Fetal and postnatal thymocytes and circulating T lymphocytes were evaluated for six cytochemical reactions. Acid phosphatase activity was present in a high percentage of cells in all threee groups. Beta-glucoronidase and alpha-naphthyl acetate acid esterase were negative in the most immature fetal thymocytes, but become increasingly positive with T-cell maturation. Only the circulating lymphocytes presented a high percentage of N-acetyl beta glucosaminidase, alpha-naphthyl acetate esterase and alpha-naphthyl butyrate esterase positive cells. This study discusses the presence of these enzymes as proportional to different stages in T-cell maturation, and also of certain cytochemical phenotypes characteristic of these stages.

Acetylglucosaminidase↗
PubMed1980

Primary intestinal lymphangiectasia. Comparison between endoscopic and radiological findings.

Two children with primary intestinal lymphangiectasia (PIL) are presented, both of whom had been prescribed an MCT supplemented diet low in long chain fatty acids. The hypoproteinemic edema improved in one patient, but persisted in the other. Following several years of dietary therapy, both subjects were re-evaluated, and a duodenoscopy and radiography of the digestive tract were performed. The duodenoscopic procedure evidenced two types of lymphangiectatic plaques on the surface of the duodenal mucosa: one form had a diameter of less than 1 mm, while the other exceeded 3 mm. The smaller lesions were seen in the child with the more favorable clinical course, whereas both types were observed in the other patient. Radiological examination disclosed the typical anomalies of intestinal lymphangiectasia only in the subject who had not responded to the dietary regimen. These results suggest that endoscopy affords a more precise assessment of the anatomic injury and could play an important role in formulating an accurate clinical diagnosis.

Child↗
PubMed1979

Immunological features in chronic lymphocytic leukaemia (CLL) of T cell origin.

Peripheral blood lymphocytes from a patient with chronic lymphocytic leukaemia of T cell origin were studied. The thymus derived nature of these lymphocytes was confirmed by surface markers, mitogen cultures, mixed lymphocyte reaction, cytotoxicity studies, and cytochemical stains. This case is notable for several clinical and laboratory findings. Among these, the benign clinical course, the reduced rate of serum immunoglobulins, the elevated number of active E rosettes, the increased PHA-induced response to low mitogen doses, the absence of PHA mediated cellular cytotoxicity, and the thy-like positivity to ANAE should be pointed out. Emphasis should be placed, however, on the loss of stimulatory ability in MLR. This last feature supports the hypothesis that these cells proliferate as a clone.

Aged↗