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L M Mora

Publications and source records attributed to L M Mora.

6 recordsLinked to original sources
PubMed1990

Evidence that G-CSF is a fibroblast growth factor that induces granulocytes to increase phagocytosis and to present a mature morphology, and that macrophages secrete 45-kd molecules with these activities as well as with G-CSF-like activity.

Evidence is provided that conditioned medium from a macrophage-like cell line contains molecules of approximately 45 kd molecular weight with granulocyte colony-stimulating factor (G-CSF)-like activity as well as with the property of inducing granulocytes to phagocytose latex particles and to mature morphologically. This type of differentiation was found to be induced on either bone marrow or induced granulocytes, but not on resident or induced macrophages. On the other hand, resident but not induced macrophages are shown to induce these types of activities when challenged by bacterial lipopolysaccharides. Evidence that macrophages produce a factor that is mitogenic for fibroblasts is also provided. This activity was measured by the induction of increased proliferation by either low-density or saturated cultures of fibroblasts. Human recombinant G-CSF was employed and found also to possess these dual capabilities of inducing both the proliferation and differentiation of granulocytes as well as the proliferation of fibroblasts. Finally, a mechanism for the regulation of myeloid cell production and differentiation is described in which G-CSF produced by macrophages not only induces granulocytes to differentiate but induces fibroblasts to proliferate and secrete macrophage colony-stimulating factor (M-CSF), which in turn makes myeloid monocyte precursors proliferate and secrete more G-CSF.

Animals↗
PubMed1989

Evidences that fibroblasts and epithelial cells produce a specific type of macrophage and granulocyte inducer, also known as colony-stimulating factor, and that monocyte-macrophages can produce another factor with proliferative inducing activity on myeloid cells and differentiative activity on macrophages.

Molecules with the property to induce proliferation of bone marrow cells in liquid cultures, and with colony-stimulating activity, were found on media conditioned (MC) by lung fibroblasts and kidney epithelial cells. These factors presented an apparent mol wt of 70,000 and 22,000 d respectively. Also when MC by epithelial cells from lungs was tested for the induction of proliferation of bone marrow cells a molecule with 22,000 d was detected. These molecules are thought to be CSF because they induce colony formation, and they are also similar in mol wt to two of the already known CSF. In fact the GM-CSF obtained from endotoxic lungs with a large epithelial cell content has a mot wt of 22,000 d, and the CSF-1 produced by a fibroblast cell line had 70,000. When the MC by fibroblast was used to induce bone marrow cells to proliferate, three new molecules with colony-stimulating activity were secreted. These molecules with apparent mol wts of 45,000, 30,000 and 17,000 d were also found in the MC by bone marrow cells when induced to proliferate with MC by epithelial cells. When the 45,000-d molecules was used in induced bone marrow cells to proliferate, once again the 30,000- and the 17,000-d molecules were secreted. Evidence is also provided that the 45,000-d molecule is produced by the monocyte-macrophage cells, and that it can induce Fc receptors or resident and elicited peritoneal macrophages. The possibility that the production of CSF is cell specific is discussed together with two models to explain the way in which these molecules can participate as proliferative (MGI-1) and differentiative (MGI-2) function in normal myeloid cell differentiation. Finally, a new terminology is proposed to classify this family of molecules.

Animals↗
PubMed1989

Conjunctivochalasis: a surgical technique.

Conjunctivochalasis can be surgically corrected when it gives an appearance of a moist eye, produces tearing by mechanical obstruction of the lower punctum, or if it impedes the normal outflow of the lacrimal film. We present a surgical technique that provides a satisfactory anatomical reconstruction, does not leave a deformity, and will not lead to a retraction that could produce a cicatricial ectropion. We stress the importance of a complete ophthalmologic examination to rule out more common causes of tearing.

Conjunctival Diseases↗
PubMed1989

Evidence that the macrophage-granulocyte inducer (MGI) is produced during cell proliferation, stored in G0, released in G1, cell specific, and induces the secretion of other colony-stimulating activities (CSA).

The secretion of the macrophage and granulocyte inducer (MGI), also known as colony-stimulating factor (CSF), by epithelial cells from lungs and kidneys, and by fibroblasts from lungs, was determined as a function of time in culture; it was found to be secreted during the initial exponential proliferation period, and not when the cells approached saturation density. When the cells were again induced to proliferate, large amounts of CSF were released after 3 h, thus hinting at the existence of a reserve pool. A CSF activity of 70,000 daltons was found in cultures of fibroblasts from lungs, kidneys, and the peritoneal cavity, a 45,000-dalton CSF was obtained from mouse peritoneal macrophages, and from bone marrow cells when activated for macrophage proliferation, and a 22,000-dalton CSF was found from epithelial cells, thus suggesting that the different CSFs are cell specific. When fibroblast CSF was used to induce bone marrow cells, three new molecules with colony-stimulating activity were produced, of 45,000, 30,000, and 17,000 daltons. The fraction with the 17,000-dalton activity also contained interleukin 1 activity, hinting at an indirect induction of colony formation by this factor. Finally the possible existence of a cascade reaction in which one CSF induces the appearance of other CSFs during the normal regulation of myeloid cell differentiation is discussed.

Animals↗
PubMedDate not supplied

Induction of Fc receptors on murine macrophages and leukemic cells by interleukin-1 beta.

Recombinant human interleukin-1 beta (rhIL-1 beta) is shown to be a strong inducer of Fc receptors (FcR) on murine macrophages and not on granulocytes. Data is provided indicating that rhIL-1 beta does induce specific but not nonspecific phagocytosis. Macrophages are shown to autoinduce their FcR expression as a function of time in culture. This induction is increased by the use of exogenous rhIL-1 beta and inhibited by anti-rhIL-1 beta antibody, pointing to an autocrine regulation of FcR expression on macrophages. On the other hand the myelomonocytic cell line WEH13BD- and the macrophage like cell line WR19M.1 are also shown to be inducible for the expression of FcR by this molecule. Data is also provided showing that recombinant murine Interferon gamma (rmIFN gamma) induces FcR on both macrophages and granulocytes. Whereas polyclonal antibodies inhibit FcR induction by IL-1 on macrophages, it does not inhibit FcR induction by IFN gamma on these cells. This points to a different mechanism of induction of FcR by IFN and IL-1. Finally, the possible application of rhIL-1 beta in vivo to help the organism fight infections is discussed.

Animals↗