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Biomedical subjects

E G Bamberger

Publications and source records attributed to E G Bamberger.

5 recordsLinked to original sources
PubMed1978

Cytotoxicity of a factor from normal and abnormal human spleens for allogenic leukemia cells.

A search for an endogenous cytotoxic factor (ECF) was made by analyzing 103 spleens from normal humans and patients suffering from hematopoietic malignancies, solid tumors, inflammatory diseases, and congestive and hyperplastic splenomegalies. A highly purified ECG was obtained by a combination of gel filtration and ion-exchange column chromatography. The factor is a low-molecular-weight (less than 2,000) substance and is probably a peptide or peptide-nucleotide complex. The biologic activity of EC was assayed on myelogenous and lymphatic leukemia cells of human origin. The spleens from normal individuals produced and/or stored the largest quantity of the ECF. The amount of ECF extractable from the pathologic spleen was drastically diminished regardless of the disease or therapeutic regimen. The ECF was significantly more cytotoxic for lymphatic than for myelogenous leukemia cells.

Anemia↗
PubMed1977

Hematopoiesis in hereditarily athymic mice.

Hematopoiesis was studied in hereditarily athymic (nude) mice and athymic mice given congeneic thymus cells. Athymic and reconstituted mice had mild anemia which resulted from both hypoplasia of the bone marrow erythrocytic series and decreased iron incorporation in erythroid precursors. Untreated nude mice had hypoplastic marrows due to decrease of both erythrocytic and lymphocytic precursors. The latter was associated with a marked peripheral lymphopenia. Transplantation of thymocytes caused the number of bone marrow and peripheral lymphocytes to return to normal whereas the granulocytic series decreased. Mice reconstituted with thymocytes had marked neutrophilia, eosinophila, and monocytosis compared with either normal or athymic siblings. The number of granulocytic colonies produced by bone marrow cells in agar was very similar in normal and athymic mice with neutrophilia, thus reflecting a normal functioning granulocytic series in a marrow with decreased lymphocytic and erythrocytic cells. The transplantation of thymocytes into athymic mice had no effect on the number of colonies produced by bone marrow cells and the number of spleen colony forming units. It was postulated that maturation of the additional thymocytes permits them to interact with the few endogenous thymocyte precursors present in the nude mice for promotion of bone marrow erythrocytic and lymphocytic proliferations. Alternatively, mature thymocytes may produce factors that were responsible for the effect on lymphoid and erythroid cells.

Animals↗
PubMed1976

Absence of thymus-derived lymphocyte markers in myelogenous leukemia (Ph1+) cell line K-562.

The myelogenous leukemia cell line K-562 with a Ph1+chromosome, derived from a patient with chronic myelogenous leukemia in terminal blastic crisis, is not a bone marrow-derived lymphoblastic cell line, because the cells neither produce immunoglobulins nor possess complement receptors. Since it has been suspected that blasts found in some patients with chronic myelogenous leukemia in blastic crisis might be thymus-derived cells, we have studied several parameters to demonstrate that K-562 cells are not thymus-derived lymphoblasts. The results of this study show: (a) no cross-reactivity of antisera to K-562 cells with normal human thymocytes; (b) lack of cytotoxicity of a specific horse anti-human thymocyte globulin for K-562 cells; (c) failure of the treatment of K-562 cells with bovine thymosin to induce antigenic determinant and erythrocyte rosette receptors on K-562 cells; (d) presence of receptors for the Fc portion of immunoglobulin G; (e) absence of terminal deoxynucleotidyl transferase; and (f) cytotoxicity of monkey antiserum to K-562 cells for malignant thymus-derived cells (Molt-4). However, absorption with Molt-4 cells abolished the cross-reactivity with Molt-4 cells, whereas 60% of the antibody to K-562 cells remained in the immune serum. Studies of DNA polymerase activities revealed that K-562 cells have levels of polymerase alpha and beta, like other proliferating cells, and an RNA-dependent DNA polymerase activity, presumably representing polymerase gamma.

Antigens, Neoplasm↗