[Follow-up of allogenic bone marrow graft with DNA polymorphisms. Use of two minisatellite MS31 and MS43 probes. Comparison with data of chromosomal polymorphisms]. / Suivi de greffe allogénique de moelle osseuse par les polymorphismes de l'ADN. Utilisation de deux sondes minisatellites MS 31 et MS 43. Comparaison avec les données des polymorphismes chromosomiques.

OBJECTIVES: Allogenic bone marrow transplantation is widely used to treat many diseases of the haemopoietic system as well as metabolic disorders. Follow-up is essential to assess acceptance, rejection or post-graft relapse. This study was undertaken to evaluate the usefulness of the minisatellite probes MS31 and MS43 used as a routine follow-up test after bone marrow transplantation. METHODS: Twenty receivers of allogenic bone marrow transplants were followed-up. Two monoclonal minisatellite probes, MS31 and MS43, were used for comparison with the classical polymorphism methods. RESULTS: Fourteen cases of total chimeras, 3 cases of rejections and 3 cases of mixed chimeras were observed with the molecular probe techniques. In 19 of the 20 cases, this technique gave results compatible with classical polymorphism results. CONCLUSIONS: The minisatellite probes MS31 and MS43 were found to be sensitive, effective tests for bone marrow transplants which can be used in routine follow-up.

Trisomy 12 in B-cell chronic lymphocytic leukemia: interphase study by in situ hybridization in 75 patients.

Trisomy 12 is the most common cytogenetic abnormality in chronic lymphocytic leukaemia (CLL) and may be a prognostic indicator. In the present study, fluorescence in situ hybridization (FISH) is shown to be a method of choice for detection of trisomy 12 in interphase cells. Seventy-five cases of B-cell CLL were analysed with a chromosome 12 specific alpha satellite DNA probe and results compared with those from cytogenetic analysis. FISH showed the three hybridization spots characteristic of trisomy 12 in 32/75 patients (42.6%). Sixty-three patients were also studied by conventional cytogenetics: failure in 7 cases, normal karyotype in 28, trisomy 12 in 9 (14.3%) and in 19 cases abnormalities other than trisomy 12. In these same 63 patients, trisomy 12 was detected on 29 occasions by FISH (46%): in one case of failure by cytogenetic analysis, in 9 cases thought to have a normal karyotype, in 10 cases carrying abnormalities other than trisomy 12 and in all 9 cases showing trisomy 12 by conventional cytogenetic investigation. Correlation between trisomy 12 and the three stages of the Binet classification indicated an increasing proportion of trisomy 12 from stage A to stage C. It is concluded that fluorescence in situ hybridization is a powerful and sensitive technique for detection of trisomy 12 in CLL and although more cases will be required to confirm a correlation between the incidence of trisomy 12 and the stage of the disease, this link could be important from a prognostic point of view.

Chromosome studies in stimulated lymphocytes of 50 patients with B-cell chronic lymphocytic leukemia.

The chromosome constitutions of stimulated lymphocytes from 50 B-cell chronic lymphocytic leukemia patients were studied using different stimulation systems, i.e., TPA alone or associated with different cytokines. Adequate metaphases were obtained in 44 subjects (88%). Among 20 patients with abnormal karyotypes (45.5%), 7 had trisomy 12. The most frequent structural abnormality was a 14q+ resulting from translocations including one t(11;14) and two t(14;17), while deletions on the long arms of chromosomes 6 and 13 constituted a second common alteration. The most important finding in this series was the recurrence of a t(18;22) observed in two cases.

Specific binding of anti-N-acetyllactosamine monoclonal antibody 1B2 to acute myeloid leukaemia cells.

1B2 is an IgM monoclonal antibody binding to glycoconjugates bearing the terminal N-acetyllactosamine structure. It agglutinates human erythrocytes. Various cell lines, peripheral blood leucocytes, normal marrow and blast cells from 179 acute myeloid leukaemia (AML) and 11 acute lymphoblastic leukaemia (ALL) patients were tested for reactivity with 1B2. Myelomonocytic (CFU-GM), erythroid (BFU-E), mixed (CFU-GEMM) and leukaemic (CFU-L) progenitor cells were tested in clonogenic assays. Granulocytes, monocytes, myeloid cell lines and 152 out of 179 AML were positive. All FAB subtypes were equally recognised. Lymphocytes, T-cell and Burkitt's cell lines, and 10 of 11 ALL samples were negative. 1B2 inhibited partially day 7 CFU-GM, whereas it was not toxic for BFU-E, CFU-GEMM and day 14 CFU-GM. Leukaemic clonogenic cells were killed in 33 out of 36 AML (more than 40% growth inhibition). 1B2 identifies the more mature steps of myeloid differentiation. It may be useful in the diagnosis of AML, and is a candidate for remission marrow purging before autologous transplantation.

Clinical significance of multidrug resistance P-glycoprotein expression on acute nonlymphoblastic leukemia cells at diagnosis.

To evaluate the clinical value of the expression of multidrug resistance P-glycoprotein (P-170) on the surface of acute nonlymphoblastic leukemia (ANLL) cells, we analyzed specimens from 150 newly diagnosed patients for staining with MRK16, a monoclonal antibody (MoAb) that binds to an external epitope of P-170. Other surface markers (CD13, CD14, CD15, and CD34) were studied by the same technique. A marker was considered positive when 20% or more cells were stained. Of 150 samples, 71 were P-170-positive. These cases did not differ from P-170-negative cases with regard to age, sex, initial white blood cell (WBC) counts, or French-American-British (FAB) type (except for M3 ANLL, which were more frequently negative). However, leukemias arising from previous myelodysplastic syndrome (MDS) and therapy-induced leukemias were more frequently P-170-positive. CD34 and P-170 expression were significantly associated. All patients were treated by intensive chemotherapy. Complete remission (CR) rates were significantly lower in P-170-positive (23/71, 32%) than in P-170-negative cases (64/79, 81%) (P less than 10(-5)). CD34 positivity was also associated with a low remission rate (P less than 10(-5)). Survival was shorter for P-170- and CD34-positive patients (P less than 10(-5)). The prognostic value of both markers was confirmed in multivariate analysis. CR duration was also shorter for P-170-positive cases, but the difference is less significant (P = .05). It is concluded that P-170 analysis may be an important tool for predicting the outcome of intensive chemotherapy in ANLL patients.

Successful pregnancy following allogeneic bone marrow transplantation after conditioning by thoraco-abdominal irradiation.

A 26-year-old woman delivered a normal child 5 years after bone marrow transplantation for severe aplastic anemia. The conditioning regimen comprised high dose cyclophosphamide and thoraco-abdominal irradiation (6 Gy). This and two previous cases demonstrate that normal pregnancy can follow total body or thoracoabdominal irradiation.