Abnormalities In Bone Marrow Cells Research Articles

Chronic Myelomonocytic Leukemia in Childhood: A Retrospective Analysis of 110 Cases

AbstractChronic myelomonocytic leukemia (CMML) is a rare hematopoietic malignancy of childhood. To define the clinical and hematologic characteristics of the disease, we performed a retrospective analysis of 110 children given the diagnosis CMML irrespective of karyotype. Median age at diagnosis was 1.8 years. Neurofibromatosis type 1 was known in 14% and other clinical abnormalities in 7% of the children. At presentation, the medium white blood count was 35 × 109/L, with a median monocyte count of 7 × 109/L. Karyotypic abnormalities in bone marrow cells were noted in 36% of the patients, whereas 26% of the children had monosomy 7. Children with monosomy 7 did not differ from those with normal karyotype with respect to their clinical presentation. However, they did display some characteristic hematologic features. Of 110 children, 38 received an allogeneic bone marrow transplant (BMT). The probability of survival at 10 years was 0.39 (standard error [SE] = 0.10) for the BMT group and 0.06 (SE = 0.4) for the 72 patients of the non-BMT group. Platelet count, age, and hemoglobin F at diagnosis were the main predicting factors for the length of survival in the non-BMT group. There is a strong need for a broad agreement on nomenclature in children with myelodysplastic syndromes (MDS). We propose here to use the French-American-British classification for MDS in childhood.

Dimethoate Induces DNA Damage and Mitochondrial Dysfunction Triggering Apoptosis in Rat Bone-Marrow and Peripheral Blood Cells.

Dimethoate (DM) is an organophosphorus (OP) pesticide with wide use in the pest control. Its persistence in crops and soils could possibly cause adverse health consequences in humans as well as other non-target species. Since molecular studies confirming potential genotoxicity of DM have not been previously reported, the acute in vivo toxicological impact was evaluated in Wistar rats. Significant micronuclei induction and metaphase chromosome abnormalities in bone marrow cells exposed to three different DM doses (20, 40 and 60 mg/kg-bw) at multiple treatment durations (24, 48 and 72 h) indicated positive dose response relationship, confirming its genotoxic and cytotoxic potential. Significant mitotic index decrease was seen in dosed animals compared to vehicle control. The study used peripheral blood comet assay, indicating DM-mediated damage to DNA at all exposure levels in a time responsive manner. These assays were found to be an effective, precise, and fast technique with applied value in biomonitoring studies. Cell cycle and apoptosis along with mitochondrial membrane potential (MMP) in flow cytometric analyses confirmed DM exposure decreased MMP, affected the cell cycle, and inflicted DNA damage, which led to cellular apoptosis of leukocytes culminating into immunotoxic effects. The in silico experiments consequently augmented that DM showed acceptable binding energy value for Cyclin A2, suggesting that it could inhibit the cell cycle progression by inhibiting cyclin A2.

Detection of the Cytogenetic Aberrations in Multiple Myeloma by Using Microrray Comparative Genomic Hybridization

To detect the molecular cytogenetic abnormalities of multiple myeloma (MM) by using microrray-based comparative genomic hybridization (array-CGH) technology and to investigate its value of application in MM. The whole-genoine copy number variants (CNV) of bone marrow samples acquired from 20 cases of newly diagnosed MM patients were detected by genome-wide hybridization and scanning by CytoScan 750K Array (Affymetrix). At the same time, the chromosome abnormalities of bone marrow cells were detected by karyotype analysis and FISH using 9 specific probes: D13S319, RB1, p53, 1q21, IgH, IgH/CCND1, IgH/FGFR3, IgH/MAF, IgH/MAFB. Among the 20 MM patients, the incidence of chromosome abnormalities detected by karyotype analysis, FISH and array-CGH were 15%, 65% and 90%, respectively. The types of CNV detected by array-CGH included the gain (106), loss (156) or UPD (23). There were many different CNVs in every chromosomes except chromosome 5, 9, 18, 21 and Y. Comparison of chromosome abnormalities detected by FISH and array-CGH showed that, the positive ratio of del (13q) was 35% and 40% respectively; the positive ratio of amp (1q) was 40% and 50% respectively; the positive ratio of del (17p) was both 15%. FISH detection showed 8 cases with IgH rearrangement, meansahile the array-CGH detection showed that 4 cases had amp (11q13) (CCND1 gene), 3 cases had amp (16q23) (MAF gene), 1 case had amp (4p16) (FGFR3 gene) and 2 cases had amp (20q12) (MAFB gene). Besides, many other new chromosome abnormalities were found. More than half of MM patients have cytogenetic changes, and most of them are complex chromosomal abnormalities. By using array-CGH, more chromosome abnormalities can be detected and more cytogenetic information can be provided for clinician.

Peculiarities of chromosomal abnormalities in bone marrow cells at diagnosis of multiple myeloma

The results of cytogenetic and i-FISH investigations in bone marrow cells of 99 patients at diagnosis of multiple myeloma are presented. Metaphase chromosomes slides were prepared according to the generally accepted methods, after 24 and 96 h of cultivation in nutrient medium without stimulation. According to the clone structure, karyotypes with normal and normal/near tetraploid clones were dominated (78.3 %). With regard to the ploidy level, pseudodiploid clones were recorded more often (12.1 %), hyperdiploidy was revealed in 7.2 % cases. Among the structural rearrangements, the deletions were dominated, namely, 12.1 % were found by cytogenetic study and 34.5 % – by- i-FISH. The structural rearrangements were shown to involve chromosomes 13 and 17 (6 % and 1.2 %, respectively) more frequently using standard cytogenetic study, while del(17p) and del(13q) (24.1 % and 15.5 %, respectively) – by- i-FISH. Atypically low was a frequency of translocations involving the gene IgH (14q32) (1,8 %). Unusual distribution of the signals with the involvement of IgH gene indicates an additional mechanism for the abnormal clone formation. By the cytogenetic analysis data, 8.9% cases, by the i-FISH data, 34.5 % cases and summarizing both methods – 52.2 % cases, were referred to the group of adverse genetic prognosis during the course of disease.

The Use of Flow Cytometry in Myelodysplastic Syndromes: A Review.

Myelodysplastic syndromes (MDSs) are a heterogeneous group of hematopoietic stem cell diseases categorized by dysplasia in one or more hematopoietic cell lineages, as well as cytopenia and functional abnormalities in bone marrow cells. Several MDS classification methods have been proposed to categorize the disease and help professionals better plan in patients’ treatment. The World Health Organization classification, released in 2008 and revised in 2016, is the currently and the most used classification method worldwide. Recent advances in MDS molecular biology and innovations in flow cytometry have enabled the development of new parameters for MDS diagnosis and classification. Several groups have published flow cytometry scores and guidelines useful for the diagnosis and/or prognosis of MDS, which are mostly based on detecting immunophenotypic abnormalities in granulocyte, monocyte, and lymphoid lineages. Here, we review the current literature and discuss the main parameters that should be analyzed by flow cytometry with the aim of refining MDS diagnosis and prognosis. Furthermore, we discuss the critical role of flow cytometry and molecular biology in MDS diagnosis and prognosis, as well as the current challenges and future perspectives involving these techniques.

Chromosomal abnormalities in bone marrow cells in relapse of chronic lymphocytic leukemia

The genetic mechanism of resistance to chemotherapy in chronic lymphocytic leukemia (CLL) is yet to be established. We aimed to determine molecular cytogenetic irregularities in chromosomes of bone marrow cells (BM) in relapse of CLL. For this, a study was carried out with 63 patients including 25 women and 38 men, aged from 36 to 73 years (average age was 57 years). Cytogenetic data showed that karyotypes, according to the clone structure, were represented into 10 groups: normal; normal/near tetraploid; abnormal/normal; abnormal/near tetraploid/normal; clonal evolution; clonal evolution/normal; clonal evolution/near tetraploid/normal; independent clones; independent/normal; independent/near tetraploid/normal clones. Various structural rearrangements were detected in chromosomes such as translocations, deletions, insertions and duplications. However, deletions in chromosomes were found to be dominant in 63.8% cases involving the band positions of especially 17p12, 13q12–q14, 11q14 and 11q23. The complexity was shown by the presence of one to four abnormalities in one karyotype using i-FISH methodology. Conventional cytogenetic and molecular cytogenetic analyses may indicate that chromosome rearrangements are multilevel process in formation of resistant karyotypes either through the loss of (1) tumour suppressor genes in the areas with bands 13q14, 13q34 and 17p13.1 (2) and/or the loss of regulation of ATM gene expression in the band position 11q22.3. The results obtained using both methods have demonstrated the presence of a heterogeneous cell population with a diverse degree of resistance to chemotherapy in CLL.

Application of flow cytometry in detecting dysplasia of myelodysplastic syndromes

Myelodysplastic syndrome (MDS) is a heterogeneous disease characterized by dysplasia and ineffective hematopoiesis. The dysplasia is crucial in the diagnosis of MDS, but the morphologic abnormalities of bone marrow cells are not specific for MDS. When the morphological evaluation of marrow dysplasia and cytogenetics can not give enough informations, for diagnosis of MDS, the application of flow cytometry (FCM) for immunophenotyping in MDS will become particularly important. Multiparametric evaluation of myeloid, monocytic maturation and antigen expression pattern contribute to the identification of two or more aberrancies in MDS cases. FCM evaluation of erythroid dysplasia is particularly difficult, because of the limited availability of specific markers. By analyzing the proteins involved in cellular iron metabolism, MDS erythroid cells present an "iron-loaded" phenotype characterized by increased ferritin contents and reduced transferrin receptor, which reflects the degree of dysplasia assessed by morphology. The proportion of CD34(+) cells increased, abnormal expression of surface antigen is also important. The application of flow cytometry in detecting dysplasia of myelodysplastic syndrome is discussed in this article.

Гетерогенність хромосомних аномалій при гострій мієлоїдній лейкемії у дітей різних вікових груп

Characteristic of chromosomal abnormalities in bone marrow cells among 123 children with acute myeloid leukemia were presented according five aging groups: I – up to 2 years, II – 2–5 years, III – 5–10 years, IV – 10–15 years, V – 15–18 years. Normal karyotype wasn’t found in group up to 2 years and in low presented in another groups (5,9–10,3 %). The highest frequency of chromosomal abnormality evolution in group up to 2 years was established (69,2 %). The highest frequency of hyperdiploidy (47–50 chromosomes) in group 15–18 years (31 %) was found. More often near-tetraploidy and pseudodiploidy clones were met in group 2–5 years (47 % and 58,8 %, respectively). Between structural types in all groups were predominated translocations and deletions. In group up to 2 years was prevalented translocations (61,5 %), 2–18 years – deletions (64,7; 34,5; 45,7 and 41,4 % respectively). In group up to 2 years more often were met abnormalities chromosomes (Chr) 9, 11, 16 (in 30,8 %), 2–5 years – Chr 16, 21 (in 29,4 %), 5–10 years – Chr 11 (24,1 %), 8, 15, 17 (in 17,2 %), 10–15 years – Chr 16 (40 %) and 15–18 years – Chr 8, 9, 15, 17 (in 17,2 %).

Cytogenetics, Not Just Previous Therapy, Determines the Course of Therapy-Related Myeloid Neoplasms

Cytogenetics, Not Just Previous Therapy, Determines the Course of Therapy-Related Myeloid Neoplasms

Allogeneic Hematopoietic Stem Cell Transplantation (HSCT) for Secondary Pulmonary Alveolar Proteinosis with Trisomy-8 Myelodysplastic Syndrome

Abstract 4705[Background] Pulmonary alveolar proteinosis (PAP) is a rare disorder characterized by abnormal accumulation of alveolar surfactant protein within alveoli. Acquired PAP has been sub-classified into autoimmune and secondary PAP according to the presence of serum anti-granulocyte macrophage colony-stimulating factor (GM-CSF) autoantibody. Hematological diseases including myelodysplastic syndrome (MDS) are the most frequent causes for secondary PAP with unclear pathogenesis independent of anti-GM-CSF antibody.[Objective and method] To assess the clinical effect of HSCT for PAP, we retrospectively analyzed 4 patients with MDS who received allogeneic transplantation at Toranomon Hospital. [Case report] Case 1 is a 35-year-old male with pancytopenia. He was diagnosed with MDS-RA with trisomy 8 abnormality in January 2008. In January 2009, he had productive cough and chest X-ray and CT revealed opaque consolidation in the bilateral lower lung fields. The diagnosis of PAP was made by transbronchial lung biopsy findings. In April 2010, he underwent unrelated bone marrow transplantation (BMT). But idiopathic pneumonia syndrome as a transplant-related complication developed and died on day 55. Case 2 was a 42-year-old female who had a history of aplastic anemia with normal karyotype from March 2007. In March 2009, she had cough and abnormal chest X-ray and CT findings. The diagnosis of PAP was made by bronchoalveolar lavage (BAL) findings. At this time, the diagnosis of MDS-RAEB with trisomy 8 was made. In September 2009, she underwent unrelated cord blood transplantation. But she died by sepsis and pneumonia of Stenotrophomonas maltophilia on day 12. Case 3 was a 58-year-old female with stomatitis who was diagnosed with Behcet’s disease in 2001. In May 2001, she developed fever and productive cough. She was diagnosed with PAP by abnormal chest X-ray and BAL findings. In July 2009, she developed pancytopenia, and the diagnosis of MDS-RAEB with trisomy 8 was made. In March 2010, she underwent unrelated BMT. After transplantation, PAP was gradually improved. Case 4 was a 47-year-old male with dyspnea who was diagnosed with PAP by CT and BAL findings. At the same time, he was diagnosed with MDS-RCMD with trisomy 8. In June 2011, he underwent peripheral blood stem cell transplantation from a HLA-identical brother. His transplant clinical course was uneventful and PAP was completely improved by day 42 in CT findings.[Discussion &Conclusion] Case 1 and 2 died of pulmonary complication developed after HSCT, one is pneumonia and another was idiopathic pneumonia syndrome. In case 3 and 4, both transplant clinical course was relatively uneventful and PAP disappeared with the improvement of MDS after HSCT. It is suggested that HSCT might be the effective treatment of secondary PAP with hematological disease, but secondary PAP itself may be the risk of pulmonary complication after HSCT. As we reported the possible association of trisomy 8 MDS with PAP development in 3 cases1, all 4 MDS cases presented here revealed trisomy 8 abnormality of bone marrow cells. Disclosures:Off Label Use: Mycophenolate mofetil was off-lable use for GVHD prophylaxis.

A report of WHIM syndrome (myelokathexis)

A report of WHIM syndrome (myelokathexis)

Nutritional rehabilitation of mitochondrial aberrations in aplastic anaemia

Aplastic anaemia (AA) is a disease characterised by bone marrow hypocellularity and peripheral blood pancytopenia. AA is also associated with mitochondrial aberrations. The present study was undertaken primarily to test the hypothesis that a nutrient mixture could affect the nutritional rehabilitation of mitochondrial aberrations in AA mice. BALB/c AA mice were induced by a combination of hypodermic injections of acetylphenylhydrazine (100mg/kg), X-rays (2·0Gy) and intraperitoneal injections of cyclophosphamide (80mg/kg). We treated these mice with nutrient mixture-supplemented diets in a dose-dependent manner (1445·55, 963·7, 674·59mg/kg per d), and the effects of the nutrient mixture for mitochondrial rehabilitation were analysed in AA mice. Transmission electron microscopy showed that mitochondrial ultrastructural abnormalities in bone marrow cells, splenocytes and hepatocytes of the nutrient mixture groups were restored markedly, compared with the AA group. Mitochondrial membrane potentials of the nutrient mixture groups were increased remarkably. Western blot analysis also revealed that the nutrient mixture significantly inhibited cytochrome c release of mitochondria in the AA group. Furthermore, the mitochondrial DNA content of the nutrient mixture groups was also increased. Our data suggest that the nutrient mixture may promote the rehabilitation of mitochondrial aberrations, and consequently protects against mitochondrial dysfunction in AA mice.

Phenomenon of evolution of clonal chromosomal abnormalities in childhood acute myeloid leukemia

Analysis of chromosomal abnormalities in bone marrow cells in 116 children with diagnosis of acute myeloid leukemia (AML) was performed. Frequency of evolution of clonal chromosome abnormalities in AML constituted 42,3%. The most abundant among them were numerical abnormalities of chromosomes 8, 9, and 21 as well as secondary structural abnormalities in region 12p12, 9p22, 9q22, 9q34, 11q14-23, and 16q22. Numerical abnormalities were registered in 26,7% cases. The basic mechanism of leukemic clone evolution was trisomy, deletion and monosomy. The frequency of evolution was 7 times higher in the age group up to 2 years and twice higher in the age group up to 5 years. The high frequency of evolution was established at t(15;17)(q22;q22) and the absence at inv(16)(p13q22). The patients with clonal evolution died earlier, before reaching remission, that can be connected with heavy initial state and high frequency of relapse. Conception of abnormality clone evolution was proposed at some stages: I--appearance of balanced rearrangement; II--trisomy; III--lose of chromosomal material. Appearance of unbalanced genome in evolution possess an advantage in proliferate activity and can be connected with the answer on chemotherapy. Identity of abnormal chromosome structure at diagnosis and relapse of disease can be an evidence of the influence of chemical agent on establishment of some types of evolution of chromosome abnormalities in leukemic cells in AML in children.

Using Multiparametric Flow Cytometry to Analysis the Immunophenotypic Abnormalities of Bone Marrow Cells in Patients with MDS-RAEB.

Abstract 4856 ObjectiveThe multiparametric flow cytometry is becoming a very useful tool of the diagnosis and prognostication for patients with Myelodysplastic Syndrome(MDS). This study was aimed at using multiparametric flow cytometry to explore the immunophenotypic abnormalities of bone marrow cells from patients with RAEB. MethodsWe collected BM samples from 12 MDS-RAEB patients (6 male, 6 female, Median Age 67.5) and 20 non-MDS patients (11 male, 9 female, median age 32.5, 7 AA, 5 PNH, 3 IDA, 1 ALL, 2 CML, 2 MM). The multiparametric flow cytometric analysis was performed using an extensive panel of monoclonal antibodies. We used the conventional and secondary gating strategies to analysis the BM cells compartments such as the percents of blast cells and the expression of lineage and maturation-associated antigens of BM hemopoietic cells quantified. ResultsCompared with the non-MDS group, the proportion of blast cells increased significantly in the MDS-RAEB group (P=0.001), but the percentages of nucleated erythrocyte, lymphocyte, monocyte and granulocyte were no significant difference (P=0.954, P=0.893, P=0.730 and P=0.182). As the percentage of blasts cells increasing, the survival time became shorter (13 ± 6 vs 35 ± 15 months; P=0.02). The expressions of haemopoietic stem/progenitor cell surface marker CD34+ and T lymphocyte surface marker CD7+ on blast cells were much higher by secondary gating method than non-MDS group (P=0.009, P=0.002, respectively), while no significant difference of the expression of CD56 (P=0.375). The expressions of CD7+ and CD56+ on lymphocyte were no significant difference between the two groups (P=0.195, P=0.369, respectively), however the expression of CD19+ may be different (P=0.039). The expressions of CD33+ and CD13+ on granulocyte were no significant difference between the two groups (P=0.289, P=0.744, respectively). However, the expression levels of CD15+CD11b+, CD15+CD11b-, CD10+, HLA-DR, CD56+ in the MDS-RAEB group were significantly higher than those in the non-MDS group, specially, the levels of CD10+, HLA-DR and CD56+ were much higher (P=0.016, P=0.011, P=0.005, P=0.005 and P=0.005, respectively) and these patients showed a shorter median overall survival (15 ± 5 vs 36 ± 10 months; p = 0.03). ConclusionsThe percentage of blast cells increased in MDS-RAEB patients and the expressions of CD34+, CD7+ on blast cells and the expressions of CD10+, HLA-DR and CD56+ on granulocyte is higher than non-MDS group. It will be necessary to increase the number of cases (MDS-RAEB) to confirm our findings. Using multiparametric flow cytometry can find the immunophenotypic abnormalities more sensitively, accurately and objectively, and this new approach could provide much more useful information in the diagnosis and prognosis of MDS-RAEB patients. DisclosuresNo relevant conflicts of interest to declare.

Epidermodysplasia Verruciformis Associated with Myelodysplastic Syndrome: An Intriguing Association

Epidermodysplasia verruciformis (EV) is a rare genodermatosis characterized by massive infection with human papillomaviruses (HPVs) and development of skin cancer. Myelodysplastic syndromes (MDSs) are a group of chronic conditions that involve dysplastic hematopoiesis, peripheral blood cytopenias, and a high incidence of progression into leukemia. We describe the intriguing association of these two premalignant conditions (EV and MDS) in one patient. These diagnoses were confirmed by histopathologic examination and cytogenetic abnormalities of bone marrow cells. The patient presented initially with clinical features typical of EV and impairment of cell-mediated immunity. In the skin lesions, HPVs 23 and 25 were identified by nested polymerase chain reaction. Six years later, he had recurrent episodes of mucosal bleeding with fever, weakness, and fatigue. At this time, severe refractory anemia and neutropenia were observed, and bone marrow smears showed hypercellularity with abnormal dysplastic megakaryocytes. The cytogenetic pattern showed abnormalities involving trisomy of chromosomes 8 and 21. The patient received a diagnosis of the indolent subtype of MDS. Through the observation of our patient and review of the literature, we hypothesized that the pathomechanisms, including the role of oncogenes and cytokines, are connected to the progression to malignancy in these settings.

Ozone inhalation can induce chromosomal abnormalities in bone marrow cells of Wistar rats

Due to the wide range of applications for ozone and its increasing use for medical and industrial purposes, studying its effects has become a very important line of research. The ozone has been suspected to be a carsinogen. Because of the increasing use of ozone, the human could be more and more exposed to this gas. In this study the effects of ozone inhalation on chromosomes and its clastogenic consequences have been investigated using in vivo micronucleus assay in bone marrow cells of treated rats. Animals were treated for 6 hours a day at 3 ppm of ozone during 10 consecutive days. The micronucleus assay was performed immediately and 11 days after the last exposure. The frequency of micronucleated polychromatic erythrocyte of bone marrow (MNPCE) increased in both groups compared to the control. Such increase confirmed the clastogenic effects of ozone. The elevated frequency of MNPCE did not decrease after 11 days of the last ozone exposure. Results indicate that ozone inhalation could induce persistent chromosomal damages even to bone marrow cells which were not in direct contact to it. Also, once more, the results confirmed the usefulness of the micronucleus assay in toxicological studies.

Karyotypic Analysis of Bone Marrow Cells in Pyodermic Lesions Associated With Myelodysplastic Syndrome

Recalcitrant pyodermic lesions and neutrophilic dermatoses are often associated with subclinical myelodysplastic syndrome (MDS). In this case series, we assessed the diagnostic importance of karyotypic analysis of bone marrow cells in 4 patients with MDS-associated pyodermic eruptions treated at our university hospital. Karyotypic analysis was performed in bone marrow cells and peripheral blood lymphocytes obtained. Serum levels of granulocyte colony-stimulating factor were measured. Four patients with pyodermic eruptions or neutrophilic dermatosis had chromosomal abnormalities in bone marrow cells, including del(20)(q11;q13.3) in 2 patients, trisomy 8 in 1 patient, and t(11;22)(q23;q11) in 1 patient. Three patients without morphologic findings suggestive of MDS were diagnosed as having refractory anemia. One female patient had refractory anemia with ringed sideroblasts associated with del(20). Two patients with refractory anemia had a normal karyotype in peripheral blood lymphocytes. Two patients with elevated serum levels of granulocyte colony-stimulating factor had more active or widespread cutaneous diseases. Karyotypic analysis of bone marrow cells, but not of peripheral blood lymphocytes, is essential in proving a diagnosis of MDS-associated pyodermic lesions. The overexpression of granulocyte colony-stimulating factor, which may compensate for impaired hematopoiesis in patients with MDS, seems to be a key cytokine leading to neutrophilic infiltration.

Reaction of bone marrow hematopoiesis to the toxic effect of paclitaxel

Intraperitoneal injection of paclitaxel (Mitotax) in a single dose of 40 mg/kg was followed by an increase in the number of mitotic granulocytic and erythroid cells, hypoplasia, and pancytopenia of the bone marrow in CBA/CaLac mice. The test preparation decreased the number of hematopoietic precursor cells for erythropoiesis and granulocytopoiesis, but increased the count of polyploid cells and incidence of structural and genomic abnormalities in bone marrow cells. These changes were reversible.

Preferential suppression of trisomy 8 compared with normal hematopoietic cell growth by autologous lymphocytes in patients with trisomy 8 myelodysplastic syndrome

AbstractClinical observations and experimental evidence link bone marrow failure in myelodysplastic syndrome (MD33) with a T cell–dominated autoimmune process. Immunosuppressive therapy is effective in improving cytopenias in selected patients. Trisomy 8 is a frequent cytogenetic abnormality in bone marrow cells in patients with MDS, and its presence has been associated anecdotally with good response to immunotherapy. We studied 34 patients with trisomy 8 in bone marrow cells, some of whom were undergoing treatment with antithymocyte globulin (ATG). All had significant CD8+ T-cell expansions of one or more T-cell receptor (TCR) Vβ subfamilies, as measured by flow cytometry; expanded subfamilies showed CDR3 skewing by spectratyping. Sorted T cells of the expanded Vβ subfamilies, but not of the remaining subfamilies, inhibited trisomy 8 cell growth in short-term hematopoietic culture. The negative effects of Vβ-expanded T cells were inhibited by major histocompatibility complex (MHC) class 1 monoclonal antibody (mAb) and Fas antagonist and required direct cell-to-cell contact. Sixty-seven percent of patients who had de novo MDS with trisomy 8 as the sole karyotypic abnormality responded to ATG with durable reversal of cytopenias and restoration of transfusion independence, with stable increase in the proportion of trisomy 8 bone marrow cells and normalization of the T-cell repertoire. An increased number of T cells with apparent specificity for trisomy 8 cells is consistent with an autoimmune pathophysiology in trisomy 8 MDS.

Genotoxic Effect of Silk Dyeing Wastes in Bone Marrow Cells of Mice, Mus musculus

Untreated wastes (0.125, 0.25, 0.50 & 1.0%) from silk industries induced both gross and individual types of chromosome abnormalities in bone marrow cells of mice. The frequency of the abnormalities increased with the increase of doses. Polyploidy and aneuploidy were found to be common among the gross, while chromatid breaks, gaps acentric fragments were most common among the individual type. The waste interferred the internal milieu of cells leading to grosstype of demages, while certain ions and reactive radicals formed during their metabolism induced the breakage in the chromosomes.