agar and Myeloproliferative-Disorders

The in vitro cloning of haemopoietic precursors is a rapidly growing field. The data reviewed above and the current practical applications of the techniques can be expected to increase quite rapidly in the next decade. Despite the technical problems of tissue culture and the special problems associated with culturing human cells, it is clear that these procedures can be effectively applied at the clinical level. The value of the data obtained will vary directly with the quality of the culture techniques. Any centre undertaking these techniques must be prepared to properly equip the culture laboratory, appoint a full-time staff member for the work and maintain a constant surveillance of the quality of the culture work.

Topics: Agar; Anemia, Aplastic; Cells, Cultured; Colony-Forming Units Assay; Colony-Stimulating Factors; Culture Media; Granulocytes; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid; Leukemia, Myeloid, Acute; Monocytes; Myeloproliferative Disorders; Polycythemia Vera; Preleukemia; Primary Myelofibrosis; Time Factors

Growth characteristics of human hemopoietic cells in erythremia and chronic myeloid leukemia were studied using agar cultures with and without hemopoietic growth factors. Agar cultures, similarly to cultures on other semisolid media (plasma clot, methylcellulose) can be used for early differential diagnosis of polycythemia vera (erythremia) and secondary erythrocytosis: erythremia, but not erythrocytosis, is characterized by spontaneous (erythropoietin-independent) formation of colonies from erythrocyte precursor cells. Spontaneous colony formation from granulocyte-macrophage precursor cells can serve as an important test for early diagnosis of chronic myeloid leukemia. The study of colony formation from granulocyte-macrophage precursors and of the capacity of bone marrow cells to form colonies from hemopoietic stromal precursor cells revealed new characteristics of the studied myeloproliferative diseases. Presumably, spontaneous colony formation from erythrocytic and myeloid precursors should be regarded as a sign of tumor transformation of the studied hemopoietic cells.

Topics: Agar; Hematopoietic Stem Cells; Humans; Myeloproliferative Disorders

Peripheral blood cells from a female infant with Down syndrome and over 60% circulating myeloblasts were cultured in soft agar. Growth was virtually restricted to cluster formation, and cluster-forming cells resided almost exclusively in the very light density fraction (SG less than 1.062). Morphological assessment of clusters revealed no evidence of cellular differentiation beyond the blast cell stage. Despite receiving no specific chemotherapy, the peripheral blood normalized within 2 months, and there was no evidence of leukemia when the patient died aged 1 year from cardiac pathology. The findings indicate that caution should be exercised when assessing prognosis on the basis of in vitro growth characteristics in such patients.

Topics: Agar; Blood Cells; Cell Differentiation; Cells, Cultured; Down Syndrome; Female; Humans; Infant, Newborn; Leukemia; Myeloproliferative Disorders

The growth and differentiation of granulopoietic progenitor cells from 15 patients with haemopoietic dysplasia were studied by in vitro culture in agar-gel. After 14 d in culture whole colonies and clusters were transferred to glass slides and were stained with a modified Papanicolaou technique. The preparations were examined for cellular differentiation by counting the number of mature cells (band forms and polymorphonuclear cells) and a mitotic index was calculated from the number of mitotic cells. Patients with defective colony formation showed granulopoietic maturation defects and a reduced mitotic index was found in some colonies. Patients who had colony counts within the normal range, however, showed normal in vitro maturation. Defective colony growth in haemopoietic dysplasia generally indicates a malignant course and can occasionally be related to leukaemic transformation. The finding of in vitro maturation defects in an additional culture abnormality which may indicate a deteriorating clinical course. A defective maturation and a reduced mitotic index in vitro add support to the concept of clonal progression in malignant haemopoietic dysplasia.

Topics: Adult; Agar; Aged; Bone Marrow; Cell Division; Cell Transformation, Neoplastic; Cells, Cultured; Female; Humans; Male; Middle Aged; Mitotic Index; Myeloproliferative Disorders; Preleukemia

Four children with chronic myeloproliferative disorders (three with Philadelphia [Ph1] chromosome-positive chronic myelogenous leukemia [CML] were studied with soft agar culture at diagnosis (before therapy) in an attempt to define abnormalities in granulopoiesis. The three patients with CML had elevated peripheral blood golony-forming cells (CFCs) and/or normal or decreased bone marrow CFCs (in those studied). Colony-stimulating activity (CSA) was markedly decreased or absent at diagnosis in all three. Maturation of myeloid cells eithin the colonies in agar was normal, indicating that no block in myeloid maturation was present. These findings are in general agreement with results previously reported in untreated adults with Ph1 chromosome-positive CML and further define the similarity with the adult form of the disease. One Ph1 chromosome-negative patient with a clinically similar chronic myeloproliferative disorder was studied and had similarly elevated peripheral blood CFCs. She had normal CSA with a similarly high WBC count. This finding was unexpected and suggests that, unlike the patients with CML, her monocytes were capable of elaboration CSA. This difference might prove helpful in the classification of this type of disorder in cases where the Ph1 chromosome abnormality is not present.

Topics: Adolescent; Agar; Bone Marrow; Cell Division; Child; Child, Preschool; Chromosomes, Human, 21-22 and Y; Chronic Disease; Clone Cells; Culture Media; Female; Granulocytes; Hematopoiesis; Humans; Leukemia, Myeloid; Leukocytes; Male; Myeloproliferative Disorders

Topics: Agar; Cell Count; Cell Division; Centrifugation, Density Gradient; Clone Cells; Hematopoietic Stem Cells; Humans; Leukemia, Myeloid; Leukemia, Myeloid, Acute; Lymphocyte Activation; Myeloproliferative Disorders; Thymidine; Tritium

Topics: Agar; Electrophoresis; Erythrocytes; Freezing; Gels; Hemolysis; Humans; Isoenzymes; L-Lactate Dehydrogenase; Leukemia, Myeloid; Leukemia, Myeloid, Acute; Leukocytes; Lymphocytes; Myeloproliferative Disorders; Primary Myelofibrosis; Staining and Labeling