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M Saitta

Publications and source records attributed to M Saitta.

13 recordsLinked to original sources

The immunophenotype in infant acute lymphoblastic leukaemia: correlation with clinical outcome. An Italian multicentre study (AIEOP).

A detailed analysis of immunophenotype of 112 infants aged less than 18 months with acute lymphoblastic leukaemia (ALL) was performed. Patients were divided into three groups on the basis of age at presentation (under 6 months: group 1: 6-12 months: group 2; 13-18 months: group 3). There were three cases of T-ALL (2.6%). The proportion of other subtypes was: common ALL in 59 patients (52.68%), pre-B ALL in 15 patients (13.3%), pre-pre-B ALL in 27 (24.1%) and acute undifferentiated leukaemia (AUL) in eight patients (7.14%). In non-T ALL, positivity to CD10 (corresponding to C-ALL and pre-B ALL) was distributed in the three age groups as follows: 38.88% (group I) 65.38% (group II) and 86.36% (group III). Conversely, immature phenotypes (pre-pre-B and AUL) were found more often in the younger patients of groups I and II, as well as anomalous phenotypes, such as the presence of myeloid antigens (MyAg) and of CD7. Prognostic significance was evaluated as event-free survival (EFS) by statistical analysis. A better outcome in CD10-positive ALL than in CD10-negative ones (48% v. 25% of long-term survivors) was demonstrated in all infants. Similarly, EFS was significantly better in MyAg-negative than in MyAg-positive cases. These results were confirmed also when adjusting for white blood cell count. This allowed the identification of CD10-negative, MyAg-positive ALL, which were relatively more frequent in infants and had a poorer clinical outcome with the current therapies. This study stresses the prognostic relevance of the immunological study in infant leukaemias and its utility in choosing different therapeutic modalities for poor risk phenotypes.

Antigens, CD

Reference values for immunoglobulin kappa and lambda light chains and the kappa/lambda ratio in children's serum.

We analyzed 708 serum samples from healthy children and adolescents by immunonephelometry to obtain reference values for the immunoglobulin kappa (kappa) and lambda (lambda) light chains and for their ratio at a time of life when immunoglobulin synthesis is maturing and continually being stimulated. The lambda chain concentration that is to be maintained throughout the child's life is reached very early, just after 1 year, whereas the concentration of the kappa chains, which increases gradually, reflects the concentration of the immunoglobulins as a whole. These reference values may be useful for studying kappa and lambda chains in illnesses involving the immune system in children.

Adolescent

Co-expression of myeloid antigens in childhood acute lymphoblastic leukaemia: relationship with the stage of differentiation and clinical significance.

Co-expression of myeloid antigens on the leukaemic blast cells was evaluated in 532 children with a diagnosis of acute lymphoblastic leukaemia (ALL). Using a panel of monoclonal antibodies belonging to CD11b, CD13, CD14, CD15 and CD33 an overall incidence of 4.3% was found, with values ranging between 1.8% for CD14 and 6.1% for CD15. When the data were further dissected, a significantly higher incidence of co-expression was noted in null-ALL (15/70 cases = 21.4%), compared to cases expressing a more mature immunophenotype, i.e. common-ALL (7/394 cases = 1.7%) and T-ALL (1/68 cases = 1.4%) (P less than 0.001). In null-ALL, 9/15 patients were infants, five of whom with the t(4;11); two further children also had a t(4;11). The clinical outcome of the 23 cases which co-expressed myeloid antigens was unfavourable. Only two of the 15 null-ALL, two of the seven common-ALL and the unique case with T-ALL are in fact in persistent first remission between 19 and 93 months from diagnosis. Though the overall incidence of childhood ALL expressing myeloid antigens is low, the evidence that this co-expression may be related to an unfavourable clinical course and that it more frequently occurs in null-ALL, particularly in the first year of life, suggests that the routine assessment of myeloid antigens may allow to identify a subgroup of childhood ALL with a poor clinical outcome.

Adolescent

Evidence for a DIOA-sensitive [K+,Cl-]-cotransport system in cultured vascular smooth muscle cells.

The existence of a [K+,Cl-]-cotransport system in vascular smooth muscle cells was investigated in the A10 cell line by studying the effect of DIOA (dihydroindenyl-oxy-alkanoic acid, a potent inhibitor) on K+, Rb+ and Cl- fluxes. Hypotonic medium (150 mOsm) increased initial rates of ouabain and bumetanide-resistant (OBR) Rb+ uptake by 100%, bumetanide and DIDS-resistant Cl- uptake by 200%, and OBR net K+ efflux by 130%. DIOA inhibited 40 to 100% of the Rb+ influx and net K+ efflux stimulation with an IC50 of 4 X 10(-5) mol/L. DIOA-sensitive Rb+ influx was a sigmoidal function of the decrease in osmolarity, with a threshold at about 230 mOsm. Our results suggest that vascular smooth muscle cells have a DIOA-sensitive [K+,Cl-]-cotransport system. Dissipation of the outwardly directed Cl- gradient with an apparent [Cl- to K+] stoichiometry much higher than one may provide the energy to ensure net KCl (and osmotic water) extrusion and cell volume regulation in these cells.

Animals

[The immunological profile of children with Down's syndrome].

In 1965 Benda demonstrated that bioptic and autoptic material of children with Down's syndrome showed hypoplasia of the thymus with poor histological differentiation between the cortex and medulla and impairment of Hassal's corpuscles which were also fewer than normal. In the seventies studies revealed the increased susceptibility to infections and higher incidence of leucosis in Down's syndrome patients as well as changes of immunologic defences (in particular cell mediated immunity). This study examines 35 children (16 boys and 19 girls) aged 6 months-20 years. Subjects were divided into a group of 18 cases in poor health with a history of recurrent infections and a group of 17 children in good health. Skin tests were performed by inoculating 0.1 ml of a solution formed by 1 ml physiological solution and 0.1 ml tetanus toxoid. Skin reaction was evaluated 48 hours later. Lymphocyte typing tests were performed with the rosette method and with monoclonal antibodies for T lymphocytes and with the determination of surface immunoglobulins for B lymphocytes. OKT4 (T helper), OKT8 (T suppressor) subsets assayed and the OKT4/OKT8 ratio was determined. Skin tests were negative in 3 cases (8.6%). The number of B lymphocytes was normal in all children. Total number of lymphocytes was decreased in 51.4% of cases. Two subjects had a reduction of OKT4 and 14 had an increased of OKT8 and 16 a significantly lower OKT4/OKT8 ratio. It is clear that skin tests were normal also in those children with low total lymphocyte values. The most closely related parameter to mobility was the OKT4/OKT8 ratio and the most distantly related on was the skin test. Only 3 cases had modifications of all 3 parameters together. Apart from the constant and complete immunological deficit described by many authors and which we cannot confirm the results of this study are in agreement with those of other authors.

Adolescent

Genotypic characterization of common acute lymphoblastic leukemia may improve the phenotypic classification.

The reactivity of five anti-B monoclonal antibodies (McAb)-OKB2 (CD24), B4 (CD19), Leu12 (CD19), BA1 (CD24), B1 (CD20)--as well as the presence of cytoplasmic immunoglobulins (CyIg) were assessed in 100 cases of common acute lymphoblastic leukemia (cALL) at presentation (TdT+, J5 [CD10]+, HLA-Dr+). All cases studied revealed one or more B-cell related markers and a hierarchy in their expression was documented: OKB2 was positive in all cases tested (100%), B4 was expressed in 96.4% of cases, Leu12 in 95.8%, BA1 in 94.9%, B1 in 18.3%, and CyIg in 23%. Further evidence of the B-cell origin of cALL was obtained by molecular analyses at the DNA level which demonstrated the presence of an Ig heavy chain gene rearrangement in all 37 cases assessed, while 37.8% showed a light chain gene reorganization. A genomic subclassification of cALL demonstrated that the majority of cases showed an immature molecular configuration with one (8.1%) or both (54.1%) Ig heavy chain alleles rearranged and a germ-line configuration of the light chain genes; 27% revealed a heavy chain gene involvement and one k allele rearranged. Only four cases (10.8%) showed a more mature configuration with both k alleles rearranged or a gamma chain gene involvement. This study confirms that cALL is characterized by the proliferation of immature B-lineage-committed elements and indicates that the leukemic cells are blocked at different levels of B-differentiation which may be recognized with the use of multiple phenotypic or genotypic B-cell-related markers.

Alleles

[Development of suture materials: from the beginning to our day].

The history of suture materials from the beginnings to the II World War is reported. In this period, catgut and silk were the most employed sutures. The appearance and successive development of synthetic materials revolutionized the field of surgical sutures. This evolution is still active, to the search of ideal suture line.

History, 17th Century

Relevance of anti-T monoclonal antibodies in the study of children with primary immunodeficiencies.

T-cell phenotypic analysis with anti-T monoclonal antibodies (MoAb) was performed on 37 children with immunologic disorders. Abnormalities of T-cell differentiation and/or of T-cell subset distribution were observed in many patients. In particular two infants with severe combined immunodeficiency showed immunologically incompetent common thymocytes (OKT6+) in the circulation, in one case a proportion of OKT6+ cells was OKT4-, OKT8-. A boy with a selective T-cell defect synthetized normal levels of Ig classes, despite the marked reduction of helper/inducer T-cells (OKT4+). Irregularities of T-cell subsets were also noted in children with Wiskott-Aldrich syndrome and in some patients with selective IgA defect or hypogammaglobulinaemia. In one of these, in whom the agammaglobulinaemia was caused by EBV infection, a persistently reversed OKT4+/OKT8+ ratio together with an excessive suppressor T-cell function were found more than 10 years after the onset of the disease. Such a case supports the hypothesis that a viral infection may cause, in a predisposed host, both the agammaglobulinaemia and an abnormality of the regulatory T-cell subpopulations. Such abnormalities, together with those found in the other children studied, underline the importance of MoAb against different T-cell antigens for a better characterization of primary immunodeficiencies.

Adolescent