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Biomedical subjects

L Campos

Publications and source records attributed to L Campos.

At least 109 records · Page 6Linked to original sources

Surface marker expression in adult acute myeloid leukaemia: correlations with initial characteristics, morphology and response to therapy.

The clinical significance of surface markers was investigated in 145 cases of acute myeloid (AML) or undifferentiated leukaemia (AUL), using a panel of six monoclonal antibodies directed to NHL-30.5 antigen (expressed on poorly differentiated myeloid cells), CD13, CD14, CD15, CD33 and CD34 antigens. Expression of CD14 was correlated with higher leucocyte count, higher serum lactate dehydrogenase level and presentation with extramedullary disease. There was no strict correlation with the French-American-British classification. However, the expression of CD14 was associated with monocytic subtypes. CD15 was mainly expressed in M2 and M3 subtypes, and NHL-30.5 and CD34 antigens in AUL and M1 leukaemias. All patients were treated with the same intensive induction treatment. Staining by three antibodies had a prognostic value. The complete remission (CR) rates were 38% (26/68) in NHL-30.5-positive versus 75% (62/77) in NHL-30.5-negative cases (P less than 10(-5), 50% (37/74) in CD34-positive versus 72% (51/71) in CD34-negative cases (P = 0.007) and 70% (77/110) in CD15-positive versus 31% (11/35) in CD15-negative cases (P less than 10(-4). Expression of NHL-30.5 and CD34 antigen was associated with shorter survival (P less than 10(-3) and P less than 10(-2) respectively), whereas survival was longer in CD15-positive cases (P less than 10(-3). In multivariate analysis, expression of NHL-30.5 antigen, absence of CD15, and high LDH level were associated with poor survival. CR duration was not influenced by any of the factors studied, including antigen expression. These results suggest that leukaemias with less differentiated phenotype have a lower response rate to induction treatment.

Acute Disease↗

Expression of immunological markers on leukemic cells before and after cryopreservation and thawing.

We have studied the effects of cryopreservation on the viability and on the expression of surface antigens of acute leukemia cells. Marrow samples were obtained at initial diagnosis from 89 patients with acute myeloid leukemia (AML), acute undifferentiated leukemia (AUL), and acute lymphoid leukemia (ALL). In AML, the mean viability was greater than 90% in the types M1, M4, and M5 of the French-American-British classification, 79% in M2, and 3% in M3 types. The viability was 74% in AUL. In ALL, the viability was 95% for pre-B leukemias, but only 2% in T-cell leukemias. The expression of myeloid antigens was studied before and after freezing and thawing using three monoclonal antibodies (NHL30.5, against poorly differentiated granulocytic leukemias, VIMC6 against differentiated granulocytic leukemias and granulocytes; and UCHM1 or CRIS-6, against monocytic leukemias and monocytes). The percentage of cells stained by NHL30.5 and UCHM1 or CRIS-6 was very similar before and after cryopreservation. For VIMC6, the mean staining after cryopreservation was 60% of the initial one. In pre-B ALL, the stainings by anti common ALL antigen before and after cryopreservation were also very similar. We conclude that leukemic cryopreserved cells are suitable for immunologic studies. The recovery is, however, very low in promyelocytic AML and T-cell ALL.

Acute Disease↗

Expression of CD 19 antigen on acute monoblastic leukemia cells at diagnosis and after TPA-induced differentiation.

We have previously shown that CD 19, a B-lymphoid differentiation antigen, is expressed on acute myeloid leukemia cells. In this study, the expression of CD 19 and CD 14 (a monocytic antigen) was investigated in 18 cases of acute monoblastic leukemia. The staining by anti-CD 19 antibody (SB4) ranged between 26 and 81% of the cells, and was significantly correlated with the staining by anti-CD 14. Double stainings confirmed that the antigens were expressed on the same cells. After a 48-hr culture in the presence of TPA, most cells became adherent and lost CD 19 antigen, whereas CD 14 was still expressed with only minimal changes. It is concluded that CD 19 antigen is expressed on more immature stages of monoblastic leukemias. The hypothesis that CD 19 could be an early monocytic differentiation antigen is discussed.

Antigens, CD19↗

Acute leukaemia following high-dose chemoradiotherapy with bone marrow rescue for ovarian teratoma.

A case of acute leukaemia following intensive chemo- and radiotherapy for solid tumour is reported. A 15-year-old girl received four courses of chemotherapy with adriamycin, cyclophosphamide and cisplatinum after the surgical diagnosis of ovarian immature teratoma. An intensification treatment was performed with cyclophosphamide and total body irradiation, followed by marrow rescue. The diagnosis of myelomonocytic acute leukaemia was performed 8 months later. The patient died after a transient improvement following a treatment by hydroxyurea. The roles of the primary tumour, of the chemotherapy and of the marrow transplantation in the occurrence of leukaemia are discussed.

Acute Disease↗

Surface markers in acute non-lymphoid leukemia: analysis with a panel of 36 monoclonal antibodies.

The reactivity of a panel of monoclonal antibodies was studied in fifty-four cases of acute myeloid (AML) or undifferentiated (AUL) leukemias. Thirty-six antibodies from the Myeloid section of the Second Workshop on Human Leukocyte Differentiation Antigens were used in an indirect immunofluorescence assay. The antibodies could be classified into three groups recognizing respectively granulocytic, monocytic or granulomonocytic leukemias. Most antibodies stained erythroblastic and megakaryoblastic leukemias. In each group, it was possible to define antibodies staining either the less differentiated forms (FAB M 1 and M 5 a) or the more differentiated forms (M 2, M 3, M 4 and M 5 b). Six out of eight AUL were stained by some of the antibodies (mainly from the monocytic group). However, a heterogeneity of stainings in a same blast population was observed.

Acute Disease↗

Early diagnosis of ABO haemolytic disease of the newborn.

To assess the usefulness of cord blood tests in diagnosing ABO-haemolytic disease of the newborn (ABO-HDN), 132 term, adequate for gestational age (AGA) neonates were evaluated. The tests studied and their significant results were: quantitative elution test (greater than or equal to 1/16), direct Coombs test (positive), bilirubin concentration (greater than or equal to 4 mg/dl). In none of the 56 O+ newborn infants delivered by O+ women were the results of any test positive. Of the 76 A+ and B+ newborn infants delivered by O+ women, 17 (22%) developed ABO-HDN. When the combined result of any two tests was positive, the sensitivity, the specificity and the positive predictive accuracy for the diagnosis of ABO-HDN was higher than for any one of the isolated tests. The probability that ABO-HDN was present when the results of at least two cord blood tests were positive was 70%, and the probability that ABO-HDN was not present when less than two cord blood tests gave positive results was 93%. It is suggested that the combination of quantitative elution test, bilirubin concentration and direct Coombs test in the cord blood is useful for an early diagnosis of ABO-HDN.

ABO Blood-Group System↗

Expression of a B-lymphoid differentiation antigen (CD 19) on acute non-lymphoblastic leukaemia cells.

The expression of CD 19 (B4) surface antigen was investigated in 41 cases of acute myeloid leukaemia (AML), and 8 cases of acute undifferentiated leukaemia (AUL). Diagnosis was carried out by usual cytological and cytochemical means, and leukaemias were classified according to the FAB classification. CD 19 antigen is thought to be expressed on B lymphoid cells only. However, 2 cases out of 9 FAB M1, M2 and M3 subtypes were weakly stained (20 to 25%) by B4 antibody; 7 out of 11, and 17 out of 18 cases of M4 and M5 subtypes were markedly stained (25 to 70% of cells). 3 cases of AUL were also stained. Moreover, B4 expression was often correlated with expression of monocyte-associated antigens, as recognized by CRIS6, My9, KiM1 and UCHM1 antibodies. It is concluded that B4 antigen is probably expressed before B differentiation and is retained in early stages of monocytic differentiation.

Antigens, Neoplasm↗

Variations in morphological and immunological blast cell phenotype in a case of acute leukaemia with t(4;11) translocation.

A case of acute leukaemia with t(4;11) chromosomal abnormality in a 28-year-old woman is reported. At diagnosis, two blast cell populations were seen: 60% of the cells were small cells with lymphoid morphology, 40% were large cells with monocytic morphology. Cytochemical examination was consistent with acute myeloid leukaemia (peroxidase-positive in 10% of the cells), but surface markers were those of common acute lymphoblastic leukaemia (CALLA, B4, TdT-positive, but My7-, My9- and OKM1-negative). Five days after diagnosis, although the only treatment had been platelet transfusions, there was a change in morphological and immunological phenotype: 40% of the cells were lymphoid and 60% monocytic. Lymphoid markers were expressed in only 20-40% of cells, and myeloid markers appeared on up to 60% of cells. We conclude that t(4;11) leukaemia could originate in an undifferentiated progenitor cell, which can undergo further differentiation into lymphoblasts or monoblasts, and that we were able to observe this in vivo differentiation in our patient.

Acute Disease↗

Intensive timed chemotherapy protocol for 37 resistant or relapsing acute myeloid leukemias.

Thirty-seven patients with acute myeloid leukemia in relapse or at initial diagnosis but resistant to conventional induction regimen have been treated by single-cycle timed sequential chemotherapy, including continuous infusion of cytarabine over 72 hours on Days 1-3 and 8-10 and short injections of daunorubicin on Days 1-3. There were 21 complete remissions (56%), 11 failures, and five early deaths. For responders, median durations of complete remission and survival were 7 and 12 months, respectively.

Adult↗

Serum beta 2 microglobulin in adult myeloid acute leukemias.

Serum beta 2 microglobulin levels, measured by radioimmunoassay (Phadebas test), were found increased in acute myeloid leukemias at diagnosis. Serum beta 2 microglobulin levels were significantly higher in patients with monocytic leukemias (13 patients, M4-M5 FAB classification) than in those with other cytological types (18 patients). Beta 2 microglobulin levels at diagnosis were correlated with serum lysozyme levels, but they were not correlated with blood blast counts, serum LDH and ferritin levels. 195 serum beta 2 microglobulin measurements were made serially in 30 patients with acute myeloid leukemias in first remission. Compared to values at diagnosis, beta 2 microglobulin levels in remission were significantly decreased. Out of 30 patients in remission 12 had increased serum beta 2 microglobulin levels (greater than 3 mg/l). Serial measurements were not predictive for relapses.

Adolescent↗

Susceptibility of acute myelogenous leukemia blasts to lysis by lymphokine-activated killer (LAK) cells and its clinical relevance.

To help understanding host-tumor relationships in acute myelogenous leukemia (AML) and better define indications for interleukin 2 (IL-2) therapy in this disease, we studied the relationship between the susceptibility of leukemic cells of 44 AML patients to lysis by autologous (26 cases) and/or allogeneic (41 cases) lymphokine-activated killer (LAK) cells and characteristics of the leukemia. Lymphocytes were activated in the presence of 1000 u/ml recombinant IL-2 for 5 days. Lysis of AML cells was studied by 51Cr release. Average lysis of AML cells by autologous LAK cells was 9 +/- 13% and by allogeneic LAK cells 10 +/- 9% with a significant correlation between lyses by both effectors (p = 0.01). Autologous (p = 0.005) and allogeneic (p = 0.004) lyses were higher in patients with initial infection. Allogeneic lysis was correlated with initial WBC count (p = 0.009), serum lactic-dehydrogenase level (p = 0.05), and expression of CD13 (p = 0.01). Autologous lysis was inversely correlated with expression of CD34 (p = 0.003). Expression of adhesion molecules CD54 (ICAM-1) and CD58 (LFA-3) by the leukemic cells did not correlate with their lysis by LAK cells. Susceptibility of leukemic cells to lysis by LAK cells did not correlate with prognosis of the leukemia.

Adult↗

[Three cases of early neurosyphilis in HIV patients].

In spite of the relative control of the disease in the late 20th century, syphilis, like other sexually transmitted diseases, has undergone a strong resurgence in recent years in the large urban centers of Europe and the US. Many patients with syphilis are also HIV+. The association between the two diseases may modify the clinical evolution of syphilis and increase the incidence of neurological disorders. We discuss the cases of three patients diagnosed with both diseases last year, with neurological presentation of syphilis occurring early and ophthalmic or cochlear vestibular involvement. This recent outbreak of syphilis seems to lead to an increase in the number of atypical cases presenting in our daily practice, where we must be prepared for early diagnosis and treatment.

Adult↗