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H A Messner

Publications and source records attributed to H A Messner.

141 records · Page 8Linked to original sources
PubMed1980

Properties of human pluripotent hemopoietic progenitors.

Human pluripotent hemopoietic progenitors (CFU-GEMM) from mixed colonies when cultured in methylcellulose or agar in the presence of erythropoietin and PHA-LCM. The observed frequency is low and varies for different individuals between 0 and 4 mixed colonies/O5 mononuclear cells. CFU-GEMM do not adhere to glass or plastic surfaces; their density is less than 1.077 g/ml, and their sedimentation velocity profile peaks at 4.5 mm/h. They do not form rosettes with sheep red blood cells. These physical parameters can be used preparatively to enrich for CFU-GEMM to facilitate assessment of their biological properties such as cycle state analysis and measurement of self-renewal capacity. Preliminary information suggests that some CFU-GEMM are capable of self-replication. Cycle state data are available for a larger number of patients with various clinical conditions. CFU-GEMM were found to be quiescent under steady-state conditions. They proliferate actively during bone marrow regeneration and in stem cell disorders like Polycythemia rubra vera or CML. These changes in cycle state activity were not reflected in numerical alterations of CFU-GEMM. It was thus concluded that the assay may be used more meaningfully to assess biological properties of human pluripotent progenitors rather than their frequency.

Cell Adhesion↗
PubMed1979

Cytotoxicity of adriamycin and daunorubicin for normal and leukemia progenitor cells of man.

A colony assay available for a subpopulation of acute myeloblastic leukemia blasts with proliferative potential was used to measure adriamycin (adria) and daunorubicin (dauno) dose-response curves following brief exposure to either drug and washing. The dose-response curves were simple negative exponentials that might be characterized by D10 (dose required to reduce survival to 10%) values. The D10 values ranged from 0.47 to 20.8 microgram/ml for adria (8 patients) and from 0.06 to 0.34 microgram/ml for dauno (3 patients). Controls consisted of committed granulopoietic and T-lymphocyte progenitors. Four measurements of granulopoietic progenitors yielded D10 values from 2.5 to 11.5 mug/ml for adria and from 0.44 to 1.2 microgram/ml for dauno. T-lymphocyte precursors from 4 normal individuals were resistant. However, following incubation of normal leukocytes with phytohemagglutinin, DNA synthesis commenced in T-lymphocyte precursors for 3 additional normal controls, which was associated with an increased data sensitivity with D10 values ranging from 4.4 to 6.2 microgram/ml.

Animals↗
PubMed1979

Proliferative state of human pluripotent hemopoietic progenitors (CFU-GEMM) in normal individuals and under regenerative conditions after bone marrow transplantation.

The proliferative state of human pluripotent hemopoietic progenitors (CFU-GEMM) was assessed in normal bone marrow transplant donors and in recipients after engraftment using the tritiated thymidine suicide method. In contrast to BFU-E and CFU-C, CFU-GEMM were found to be quiescent. In samples obtained during early regeneration after transplantation, CFU-GEMM were significantly reduced after short-term exposure to 3H TdR when compared to controls. This observation suggests active participation of CFU-GEMM in bone marrow regeneration.

Bone Marrow Cells↗
PubMed1979

Empiric therapy for infections in granulocytopenic cancer patients: continuous infusion of amikacin plus cephalothin.

A combination of amikacin sulfate given by continuous infusion (800 mg/sq m/24 hr) plus cephalothin sodium (2 g every four hours) was used as initial empiric therapy for the treatment of 65 evaluable febrile (greater than 38.5 degrees C) episodes in 54 granulcoytopenic (neutrophils, less than 1,000/microliter) adult cancer patients. Carbenicillin disodium (5 g every four hours) was substituted for cephalothin in patients with Pseudomonas infections and in patients in whom the initial regimen was unsuccessful. Thirty-two of the 38(84%) identifiable infections responded to therapy, including all of the eight septicemias and eight of 11 pneumonias. Three additional infections responded to the substitution of carbenicillin for cephalothin, for a total response rate of 92% (35/38). Nephrotoxicity occurred in five patients (7.1%), most commonly in patients over 60 years of age. Ototoxicity, highly correlated with a duration of greater than 19 days and a total dosage of greater than 25 g of amikacin sulfate, occurred in four patients (5.6%). Amikacin given by continuous infusion plus cephalothin is a safe and efficacious empiric therapy for infections in granulocytopenic cancer patients.

Acute Disease↗
PubMed1979

Identification of megakaryocytes, macrophages, and eosinophils in colonies of human bone marrow containing neurtophilic granulocytes and erythroblasts.

Pluripotent hemopoietic progenitors in human bone marrow can be identified by their ability to give rise in culture to colonies that contain more than one lineage of hemopoietic differentiation. Growth of these mixed colonies is supported by media conditioned by leukocytes in the presence of phytohemagglutinin (PHA-LCM) and erythropoietin. They can be readily recognized by direct microscopic observation because of their composition of colorless cells and cells with a red appearance typical for hemoglobin. Seventy-three individual mixed colonies from 6 individuals were prepared by cytocentrifugation for further cytological examination. In addition to neutrophilic granulocytes and erythroblasts, megakaryocytes were present in 16 of the 73 colonies, as identified by positive reaction for acid phosphatase. Macrophages were found in 24 and eosinophils in 6 of the 73 colonies.

Bone Marrow Cells↗
PubMed1978

Purification of terminal deoxynucleotidyltransferase by oligonucleotide affinity chromatography.

Terminal deoxynucleotidyltransferase is an enzyme which has been found to be associated with thymus cells, bone marrow cells, as well as leukocytes from patients with acute lymphoblastic leukemia and chronic myelocytic leukemia in blast crisis. We report here the purification of terminal deoxynucleotidyltransferase by an oligonucleotide affinity (oligo(dT)12-18 cellulose) column. By using a 35 to 70% (NH4)2SO4 cut, Sephacryl S200 column and an oligo(dT) cellulose column, terminal deoxynucleotidyltransferase has been purified from calf thymus cells to a specific activity of more than 8,500 units/mg of protein. The terminal deoxynucleotidyltransferase purified by this method contains no detectable DNA-dependent DNA polymerase or endonuclease activities. Furthermore, sodium dodecyl sulfate-polyacrylamide gel electrophoresis showed that the enzyme appears to be homogeneous, with two polypeptides corresponding to the two subunits alpha (10,000) and beta (23,000) of terminal deoxynucleotidyltransferase. These data indicate that oligo(dT)12-18 cellulose can be used as a rapid and selective affinity column for the purification of terminal deoxynucleotidyltransferase.

Animals↗
PubMed1978

Granuloerythropoietic colonies in human bone marrow, peripheral blood, and cord blood.

Colonies that contain granulopoietic and erythropoietic cells can be grown in specimens of human bone marrow, peripheral blood, and cord blood. Growth of these colonies is promoted by media conditioned by leukocytes in the presence of phytohemagglutinin (PHA-LCM) and the addition of erythropoietin on days 4 or 5 to the cultures. Sedimentation velocity profiles for these granuloerythrocytic colonies suggest their origin from single cells (CFU-G/E) rather than from doublets or clumps. This hypothesis is supported by cocultivation of male and female specimens. Cells in granuloerythrocytic colonies that developed in such mixing experiments were either uniformly female by Y-chromatin analysis or contained Y-chromatin bodies in both the granulocytic and erythroid cells.

Blood Cells↗
PubMedDate not supplied

Evaluation of epoetin alpha (rHuEPO) and darbepoetin alpha (DARB) on human burst-colony formation (BFU-E) in culture.

The erythropoietic effect of recombinant human erythropoietin, epoetin alpha (rHuEPO), in promoting the growth of erythroid burst-forming units (BFU-E) was compared with darbepoetin alpha (DARB), a rHuEPO analogue obtained by site-directed mutagenesis. Human bone marrow cells derived from healthy donors were cultured with different concentrations of rHuEPO or DARB for 12 - 21 days and BFU-E were counted using an inverted microscope. The EC50 of rHuEPO was about 10-fold lower than DARB and the size of the colonies was significantly larger in rHuEPO-containing cultures using comparable concentrations. The maximum number of colonies obtained in some rHuEPO-containing cultures was also higher than for DARB. The number of colonies in DARB-containing cultures was increased, in part, by the addition of low concentrations of rHuEPO, but not by DARB, even at high concentrations. We conclude that DARB is not as effective as rHuEPO in supporting the in vitro growth of human BFU-E.

Bone Marrow Cells↗