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A cytotoxic common ALL antiserum (CALLA) specific for leukemic cells of most patients with non-T-cel- acute lymphoblastic leukemia (ALL) and of some patients with chronic myelogenous leukemia (CML) in blast crisis has been reproducibly prepared using cell lines for absorption. CALLA reacts with leukemic cells of 110 of 134 patients (82%) with non-T-cell ALL; 1 of 71 (1%) patients with acute myelogenous leukemia (AML); 2 of 7 patients (29%) with chronic myelogenous leukemia in blast crisis; 7 of 92 patients (8%) with other hematologic malignancies; and with the leukemic cell lines Laz 221 and NALM-1. It does not react with the normal hematopoietic cells,B- or T-cell lines,or cells from 26 patients with T-cell ALL that were tested. CALLA reactivity and periodic acid Schiff (PAS) staining correlate poorly,with CALLA reacting with cells from 86% (64 of 74) of patients with PAS-positive and 76% (29 of 38) of those with PAS-negative non-T-cell ALL. In these patients,CALLA reacts with cells from 89% of those under age 12 (78 of 88); 74% of those aged 12--20 (20 of 27); and 58% of those over 20 (11 of 19). Using only CALLA and antisera specific for Ia-like and T-cell antigens,we can now distinguish most cases of ALL from AML and other hematologic malignancies. View Publication

The glycoprotein hormone erythropoietin regulates the level of oxygen in the blood by modulating the number of circulating erythrocytes,and is produced in the kidney or liver of adult and the liver of fetal or neonatal mammals. Neither the precise cell types that produce erythropoietin nor the mechanisms by which the same or different cells measure the circulating oxygen concentration and consequently regulate erythropoietin production are known. Cells responsive to erythropoietin have been identified in the adult bone marrow,fetal liver or adult spleen. In cultures of erythropoietic progenitors,erythropoietin stimulates proliferation and differentiation to more mature red blood cells. Detailed molecular studies have been hampered,however,by the impurity and heterogeneity of target cell populations and the difficulty of obtaining significant quantities of the purified hormone. Highly purified erythropoietin may be useful in the treatment of various forms of anaemia,particularly in chronic renal failure. Here we describe the cloning of the human erythropoietin gene and the expression of an erythropoietin cDNA clone in a transient mammalian expression system to yield a secreted product with biological activity. View Publication

The My-10 glycoprotein is an hematopoietic cell surface antigen expressed specifically by undifferentiated (blast) cells,constituting 1%-4% of normal adult bone marrow leukocytes. We used several immunological and in vitro culture methods to analyze the expression of this unique antigen on a variety of lymphohematopoietic progenitor cells. Colony-forming cells (CFC) for granulocyte-monocyte colonies (CFC-GM) and erythroid colonies (BFU-E) were predominantly My-10 positive. CFC with higher proliferative potential were more strongly My-10 positive than CFC with lower proliferative potential,and those for mixed-lineage and blast cell colonies were even more uniformly My-10 positive. Cells maintaining CFC-GM number in short-term marrow culture (pre-CFC) were found to be My-10 positive,as were lymphoid precursors defined by their content of intranuclear terminal deoxynucleotidyl transferase. More mature erythroid precursors (CFU-E) were heterogeneous for antigen expression and lost My-10 antigen progressively,in parallel with advancing maturational stage. The My-10 antigen permits rapid identification and purification of hematopoietic progenitor cells for further study or potential clinical application. The disappearance of the My-10 antigen,moreover,may be a probe for differentiation-linked cellular events. View Publication

The proliferation and differentiation effects of the synthetic retinoid TTNPB and of 13-cis retinoic acid (RA) on hemopoietic progenitors from bone marrow of myelodysplastic syndrome (MDS) patients were compared. The addition of TTNPB or RA to culture plates containing MDS patient's marrow cells stimulated myeloid colony (CFU-C) growth and caused a significant increase in granulocytic colonies (CFU-G). In the presence of RA the increase in CFU-G was statistically insignificant. Cellular differentiation studies in liquid suspension culture revealed that the two retinoic acid analogues cause a marked decrease in immature granulocytes and an increase in mature granulocytes. There was further an increase in the number of cells that reacted positively with monoclonal antibodies (McAb) binding specifically to granulocytes (B4,3,B13,9 and Leu M4) and a decrease in the percentage of cells reacting with the McAb against Ia-like determinants. These findings indicate that TTNPB is as active as RA in stimulating the growth of hemopoietic progenitors from MDS patients and in enhancing granulocytic differentiation in liquid culture. View Publication

The amino acid sequence of a human placental bFGF was determined by a combination of protein and cDNA sequencing. The placental bFGF consists of 157 amino acid residues with a calculated molecular weight of 17,464 and is highly homologous to bovine pituitary bFGF. The human protein contains an amino terminal extension when compared to the sequence established for bovine bFGF (Esch et al.,1985) and to the sequence of the predicted translation product based on human bFGF cDNA clones (Abraham et al.,1986). View Publication

Monoclonal antibody HEA125 was used to study the tissue distribution of an epithelial cell surface glycoprotein of Mr 34,000 (Egp34). A large panel of normal and neoplastic tissues was examined for immunoreactivity with HEA125 by means of a sensitive immunoperoxidase technique. HEA125 labeled most epithelial cell types throughout the body but did not label any nonepithelial tissue. Major exceptions were epidermal keratinocytes,gastric parietal cells,hepatocytes,thymic cortical epithelial,and myoepithelial cells. Normal mesothelial cells were unreactive. In normal glandular epithelia and tubular adenocarcinomas exclusively the basolateral cell membranes were stained. HEA125 intensely reacted with all tested carcinoma specimens derived from colorectum,stomach,pancreas,liver,lung,mammary gland,ovary,thyroid,kidney,urinary bladder,and prostate including a number of anaplastic,diffusely infiltrating carcinomas. Metastatic lesions of these tumors were consistently positive. Generally,the staining of tumor cells was very homogeneous. The majority of squamous cell carcinomas were less strongly labeled than adenocarcinomas; keratinizing areas of the tumor masses were negative. Germ cell tumors and mesotheliomas of epithelioid type focally expressed the antigen. Egp34 was found to be absent from sarcomas,lymphomas,melanomas,and neurogenic tumors. Hence,HEA125 is a useful reagent for the distinction of carcinomas from nonepithelial neoplasms,even at very low degrees of histological differentiation. Furthermore,HEA125 allows the immunohistochemical detection of micrometastases originating from carcinomas. The antigen is detectable in formalin-fixed paraffin sections. View Publication

In dissociated-cell cultures prepared from the embryonic rat hippocampus,neurons establish both axons and dendrites,which differ in geometry,in ultrastructure,and in synaptic polarity. We have used immunocytochemistry with monoclonal antibodies to study the regional distribution of beta-tubulin and micro-tubule-associated protein 2 (MAP2) in hippocampal cultures and their localization during early stages of axonal and dendritic development. After development for a week or more in culture,when axons and dendrites were well-differentiated,the distribution of these two proteins was quite different. Beta-tubulin was present throughout the nerve cell,in soma,dendrites,and axon. It was also present in all classes of non-neuronal cells,astrocytes,fibroblasts,and a presumptive glial progenitor cell. In contrast,MAP2 was preferentially localized to nerve cells; within neurons,MAP2 was present in soma and dendrites,but little or no immunostaining was detectable in axons. Both beta-tubulin and MAP2 were present in nerve cells at the time of plating. From the earliest stages of process extension,beta-tubulin was present in all neuronal processes,both axons and dendrites. Surprisingly,MAP2 was also initially present in both axons and dendrites,extending as far as the axonal growth cone. With subsequent development,MAP2 staining was selectively lost from the axon so that after 1 week in vitro little or no axonal staining remained. Taken together with earlier results (Cáceres et al.,1984a),these data indicate that the establishment of neuronal polarity,as manifested by the molecular differentiation of the axonal and dendritic cytoskeleton,occurs largely under endogenous control,even under culture conditions in which cell interactions are greatly restricted.(ABSTRACT TRUNCATED AT 250 WORDS) View Publication

Plasmacytoma growth factor (PCT-GF),a putative macrophage-derived lymphokine essential for the in vitro viability and proliferation of early generation plasmacytomas,was purified from conditioned medium of the murine macrophage cell line P388D1. The purification of PCT-GF was accomplished by a batch concentration on trimethylsilyl-controlled pore glass beads,followed by: gel filtration chromatography; hydrophobic interaction HPLC; and reverse-phase HPLC. SDS-PAGE analysis of the purified PCT-GF revealed a single band of Mr 23,000. The amino terminal sequence of PCT-GF was established as NH2-Pro-Thr-Ser-Gln-Val-Arg-Arg-Gly-Asp-Phe-Thr-Glu-Asp-Thr-Thr-Pro-Asn- Arg-Pro-Val-Tyr-Thr. No significant homology was found between this sequence and proteins in the National Biomedical Research Foundation database,suggesting that PCT-GF is a new lymphokine unrelated to previously described growth and differentiation factors. View Publication

Complementary DNA clones encoding the human kidney epidermal growth factor (EGF) precursor have been isolated and sequenced. They predict the sequence of a 1,207 amino acid protein which contains EGF flanked by polypeptide segments of 970 and 184 residues at its NH2- and COOH-termini,respectively. The structural organization of the human EGF precursor is similar to that previously described for the mouse protein and there is 66% identity between the two sequences. Transfection of COS-7 cells with the human EGF precursor cDNA linked to the SV40 early promoter indicate that it can be synthesized as a membrane protein with its NH2-terminus external to the cell surface. The human EGF precursor gene is approximately 110 kilobase pairs and has 24 exons. Its exon-intron organization revealed that various domains of the EGF precursor are encoded by individual exons. Moreover,15 of the 24 exons encode protein segments that are homologous to sequences in other proteins. Exon duplication and shuffling appear to have played an important role in determining the present structure of this protein. View Publication

A cDNA clone encoding a novel hematopoietic growth factor activity produced by a gibbon T cell line has been identified using a mammalian cell expression cloning system. The sequence of this cDNA proved to have significant homology to the sequence encoding murine interleukin 3 (IL-3). The human gene,which was readily identified because of its high degree of homology to the gibbon sequence,also displayed significant homology with the murine IL-3 sequence. The recombinant gibbon IL-3 protein proved to have multipotent colony stimulating activity when tested with normal human bone marrow cells,proving that this primate hematopoietin is not only structurally but also functionally related to murine IL-3. View Publication