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J A Peyman

Publications and source records attributed to J A Peyman.

6 recordsLinked to original sources
PubMed1992

Localization of IFN-gamma receptor in first trimester placenta to trophoblasts but lack of stimulation of HLA-DRA, -DRB, or invariant chain mRNA expression by IFN-gamma.

Trophoblasts do not express MHC class II Ag on their cell surface, but it is not known at which level the regulation of expression of these IFN-gamma-responsive genes occurs. We localized the IFN-gamma R Ag to the trophoblasts of normal human first trimester placenta. As previously shown, treatment with IFN-gamma of short term cultures of placental explants did not induce expression of HLA-DR Ag in trophoblasts. We demonstrated that in situ hybridization with probes for DRA, DRB, and MHC class II-associated invariant chain genes gave no detectable signals for the presence of the corresponding mRNA in cytotrophoblasts or syncytiotrophoblasts of first trimester placenta with or without IFN-gamma. Maternal leukocytes in these placental preparations as well as IFN-gamma-treated HeLa cell control cultures expressed these mRNA. In addition, Northern analysis of RNA isolated from the trophoblast cell line Jar after treatment with IFN-gamma showed that induction of transcription did not occur from the HLA-DRA, HLA-DRB, or invariant chain genes. Jar cells expressed the IFN-gamma R Ag. These data suggest that down-regulation of MHC class II Ag on trophoblasts in the first trimester placenta and in a cell line include a lack of productive intracellular signaling by the IFN-gamma R and maintenance, in a coordinate manner, of low steady state levels of the mRNA encoded by the DRA, DRB, and invariant chain genes.

Antigens, Differentiation, B-Lymphocyte↗
PubMed1991

Effects of maternal diabetes on fetal rat lung ion transport. Contribution of alveolar and bronchiolar epithelial cells to Na+,K(+)-ATPase expression.

Fetuses of streptozotocin-induced diabetic rats exhibited delayed lung maturation and a 40% reduction in the steady-state level of lung Na+,K(+)-ATPase alpha 1 subunit mRNA and Na+,K(+)-ATPase activity at 21 d of gestation. In in situ hybridization experiments the signal specific for Na(+)-pump alpha 1 subunit message was strongest above columnar epithelial cells of air-conducting structures. Strong labeling was also present above cuboidal cells lining the forming alveoli, but not above mesenchymal cells. Immunocytochemical localization of the protein paralleled the distribution of the mRNA. Mesenchymal cells were more abundant in fetal lungs of diabetic mothers, and thus the decreased overall levels of Na+,K(+)-ATPase may result from the observed morphological pulmonary immaturity. One day after birth there was no apparent difference in lung morphology at the light microscopic level, in the localization or the steady-state level of Na+,K(+)-ATPase alpha 1 isoform mRNA, or in enzyme activity. Na+,K(+)-ATPase has a likely role in the active phase of fluid absorption in the airways of newborns before the onset of breathing. Decreased fluid clearance and lack of thinning of the lung's connective tissue may contribute to the increased risk for respiratory distress in infants of diabetic mothers.

Animals↗
PubMed1987

Different molecular forms of a glycoprotein antigen found on azurophilic granule membranes of cultured human HL60 promyelocytes and on the plasma membrane of a myeloblastoid variant line.

In previous immunohistological studies an antigen designated D46 was identified on the surface of an agranular, myeloblastoid cell line (HL60-D). It was not detected on the surface of either parental HL60 cells or variants with aberrant primary granules (HL60-A7). In these promyelocytes it was found to be intracytoplasmic, in a granular pattern. In the work presented here, this antigen and other granule-related glycoproteins were studied by radiolabeling, subcellular fractionation and gel electrophoresis. The major findings include the following: the anti-D46 antibody precipitated one major and one minor glycosylated component, each of which migrated with a different electrophoretic mobility, depending on whether it was derived from cells with or without granules. Incorporation of radioactive amino acids, but not monosaccharides, revealed an additional component of lower mobility. The D46 antigen(s) was recovered in the detergent-rich phase of a Triton X-114 extract of granules, suggesting that it is an integral membrane protein. As assessed by the relative activities of marker enzymes, the granules of both the HL60 and HL60-A7 cell lines exhibited a heterogeneous pattern of sedimentation in density gradients. The electrophoretic patterns of the major [2-3H]mannose-labeled glycoproteins of the granule-enriched fractions were similar, except for one diffuse band of 110-170 kD which was not detected in HL60-A7. These studies provide direct evidence for heterogeneity of enzymatic and membrane constituents of primary myeloid granules, and give the first indication that there may be glycoprotein changes associated with certain ultra-structural defects that occur in abnormal promyelocytes. They suggest also, in the example of the D46 antigen; that some glycoproteins may exist in different forms when localized to either the granules or the plasma membrane.

Antigens, Surface↗
PubMed1986

Differences in the plasma membrane glycoproteins of cultured myeloblastoid and promyelocytic human leukemia (HL60) cells.

Since the mechanisms that control synthesis of surface and internal granule membranes are closely-related within the Golgi apparatus, we have compared the plasma membrane proteins and glycolipids of cells of the human promyelocytic line HL-60 with those of its agranular myeloblastoid variant (HL60-D), and of other human myeloid lines (KG-1a, KG-1 and ML-2). Proteolytic degradation by granule enzymes altered the protein profiles unless multiple inhibitors were included in the cell suspension before lysis and during subsequent handling of the extracts. Polyacrylamide gel electrophoretic profiles of the proteins accessible to lactoperoxidase-catalyzed 125I-labeling or to periodate [3H]-borohydride labeling, as well as those of the glycoproteins bound to and eluted from immobilized concanavalin A, showed distinct patterns. The apparent molecular weights of the two major sialylated glycoproteins were larger in cell lines with a greater content of azurophilic granules. Also, the blastic line incorporated less fucose into glycolipid and contained less complex gangliosides and neutral glycolipids than did the parent. These data demonstrate that, within the limits of this culture model, cells capable of cytoplasmic granule production express a different constellation of surface components.

Cell Line↗